358 results on '"Distillation methods"'
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2. Helichrysum italicum : From Extraction, Distillation, and Encapsulation Techniques to Beneficial Health Effects.
- Author
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Furlan, Veronika and Bren, Urban
- Subjects
FUMIGANTS ,DISTILLATION ,ESSENTIAL oils ,BIOACTIVE compounds ,EXTRACTION techniques ,TRADITIONAL medicine ,HEALTH literacy - Abstract
Helichrysum italicum (family Asteraceae), due to its various beneficial health effects, represents an important plant in the traditional medicine of Mediterranean countries. Currently, there is a renewed interest in this medicinal plant, especially in investigations involving the isolation and identification of its bioactive compounds from extracts and essential oils, as well as in experimental validation of their pharmacological activities. In this paper, we review the current knowledge on the beneficial health effects of Helichrysum italicum extracts, essential oils, and their major bioactive polyphenolic compounds, ranging from antioxidative, anti-inflammatory, and anticarcinogenic activities to their antiviral, antimicrobial, insecticidal, and antiparasitic effects. This review also provides an overview of the most promising extraction and distillation techniques for obtaining high-quality extracts and essential oils from Helichrysum italicum, as well as methods for determining their antioxidative, antimicrobial, anti-inflammatory, and anticarcinogenic activities. Finally, new ideas for in silico studies of molecular mechanisms of bioactive polyphenols from Helichrysum italicum, together with novel suggestions for their improved bioavailability through diverse encapsulation techniques, are introduced. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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3. Integrated supercritical fluid extraction of essential oils.
- Author
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Dashtian K, Kamalabadi M, Ghoorchian A, Ganjali MR, and Rahimi-Nasrabadi M
- Subjects
- Distillation methods, Plant Oils chemistry, Plant Oils isolation & purification, Microwaves, Chromatography, Supercritical Fluid methods, Oils, Volatile chemistry, Oils, Volatile isolation & purification
- Abstract
Supercritical fluid extraction (SFE) stands out as an incredibly efficient, environmentally conscious, and fast method for obtaining essential oils (EOs) from plants. These EOs are abundant in aromatic compounds that play a crucial role in various industries such as food, fragrances, cosmetics, perfumery, pharmaceuticals, and healthcare. While there is a wealth of existing literature on using supercritical fluids for extracting plant essential oils, there's still much to explore in terms of combining different techniques to enhance the SFE process. This comprehensive review presents a sophisticated framework that merges SFE with EO extraction methods. This inclusive categorization encompasses a range of methods, including the integration of pressurized liquid processes, ultrasound assistance, steam distillation integration, microfluidic techniques, enzyme integration, adsorbent facilitation, supercritical antisolvent treatments, molecular distillation, microwave assistance, milling process and mechanical pressing integration. Throughout this in-depth exploration, we not only elucidate these combined techniques but also engage in a thoughtful discussion about the challenges they entail and the array of opportunities they offer within the realm of SFE for EOs. By dissecting these complexities, our objective is to tackle the current challenges associated with enhancing SFE for commercial purposes. This endeavor will not only streamline the production of premium-grade essential oils with improved safety measures but also pave the way for novel applications in various fields., Competing Interests: Declaration of competing interest The authors declare that they have no any type of conflict of interest., (Copyright © 2024. Published by Elsevier B.V.)
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- 2024
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4. Improving membrane distillation performance by Fe(II) activated sodium percarbonate oxidation during the treatment of shale gas produced water.
- Author
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Gu S, Qu F, Qu D, Yan Z, Meng Y, Liang Y, Chang H, and Liang H
- Subjects
- Water Purification methods, Iron chemistry, Hydrophobic and Hydrophilic Interactions, Distillation methods, Membranes, Artificial, Carbonates chemistry, Oxidation-Reduction
- Abstract
Membrane distillation (MD) offers promise for recycling shale gas produced water (SGPW), while membrane fouling is still a major obstacle in standalone MD. Herein, sodium percarbonate (SPC) oxidation was proposed as MD pretreatment, and the performance of the single MD, SPC-MD hybrid process and Fe(II)/SPC-MD hybrid process for SGPW treatment were systematically evaluated. Results showed that compared to raw SGPW, the application of SPC and Fe(II)/SPC led to the decrease of the fluorescent organics by 28.54 % and 54.52 %, respectively. The hydrophobic fraction decreased from 52.75 % in raw SGPW to 37.70 % and 27.20 % for SPC and Fe(II)/SPC, respectively, and the MD normalized flux increased from 0.19 in treating raw SGPW to 0.65 and 0.81, respectively. The superiority of SPC oxidation in reducing the deposited membrane foulants and restoring membrane properties was further confirmed through scanning electron microscopy observation, attenuated total reflection fourier transform infrared, water contact angle and surface tension analyses of fouled membranes. Correlation analysis revealed that hydrophobic/hydrophilic matters and fluorescent organics in SGPW took a crucial role in MD fouling. The mechanism of MD fouling mitigation by Fe(II)/SPC oxidation was attributed to the decrease in concentrations and hydrophobicity of organic by synergistic oxidation, coagulation and adsorption., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)
- Published
- 2024
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5. Evaluation of lavender essential oils and by-products using microwave hydrodistillation and conventional hydrodistillation.
- Author
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Kırkıncı S, Gercek YC, Baştürk FN, Yıldırım N, Gıdık B, and Bayram NE
- Subjects
- Wastewater chemistry, Phenols analysis, Phenols chemistry, Tandem Mass Spectrometry methods, Oils, Volatile chemistry, Lavandula chemistry, Microwaves, Distillation methods, Plant Oils chemistry, Gas Chromatography-Mass Spectrometry methods
- Abstract
This study investigated the impact of two extraction methods, traditional hydrodistillation (TDH) and microwave-assisted hydrodistillation (MAH), on the essential oil yield and chemical profile of Lavandula angustifolia L., as well as the bioactive potential of the resulting wastewater. Essential oil composition was analyzed via GC-MS, revealing similar qualitative and quantitative profiles for both methods, with α-terpinolene and (-)borneol as major constituents. Wastewater analysis via LC-MS/MS and spectrophotometric assays demonstrated the presence of significant total phenolic content (3.29-1.78 mg GAE/g) and 32 individual phenolics (463.1 µg/kg for TDH; 479.33 µg/kg for MAH). These findings suggest that both essential oil and wastewater obtained by either method possess considerable bioactive potential, with the MAH method potentially offering advantages over TDH for essential oil extraction. Further exploration of wastewater applications in various industrial sectors is warranted., (© 2024. The Author(s).)
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- 2024
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6. Modeling and validation of purification of pharmaceutical compounds via hybrid processing of vacuum membrane distillation.
- Author
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Obaidullah AJ and Almehizia AA
- Subjects
- Vacuum, Pharmaceutical Preparations analysis, Pharmaceutical Preparations chemistry, Pharmaceutical Preparations isolation & purification, Machine Learning, Models, Theoretical, Membranes, Artificial, Distillation methods, Algorithms
- Abstract
This study provides an in-depth examination of forecasting the concentration of pharmaceutical compounds utilizing the input features (coordinates) r and z through a range of machine learning models. Purification of pharmaceuticals via vacuum membrane distillation process was carried out and the model was developed for prediction of separation efficiency based on hybrid approach. Dataset was collected from mass transfer analysis of process to obtain concentration distribution in the feed side of membrane distillation and used it for machine learning models. The dataset has undergone preprocessing, which includes outlier detection using the Isolation Forest algorithm. Three regression models were used including polynomial regression (PR), k-nearest neighbors (KNN), and Tweedie regression (TWR). These models were further enhanced using the Bagging ensemble technique to improve prediction accuracy and reduce variance. Hyper-parameter optimization was conducted using the Multi-Verse Optimizer algorithm, which draws inspiration from cosmological concepts. The Bagging-KNN model had the highest predictive accuracy (R2 = 0.99923) on the test set, indicating exceptional precision. The Bagging-PR model displayed satisfactory performance, with a slightly reduced level of accuracy. In contrast, the Bagging-TWR model showcased the least accuracy among the three models. This research illustrates the effectiveness of incorporating bagging and advanced optimization methods for precise and dependable predictive modeling in complex datasets., (© 2024. The Author(s).)
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- 2024
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7. Membrane fouling analysis of air-gap membrane distillation (AGMD) for recovery of water and removal of antibiotics from a model wastewater containing antibiotics and humic acid.
- Author
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Kywe PP and Ratanatamskul C
- Subjects
- Waste Disposal, Fluid methods, Water Purification methods, Models, Theoretical, Temperature, Hydrodynamics, Humic Substances analysis, Anti-Bacterial Agents chemistry, Anti-Bacterial Agents analysis, Distillation methods, Membranes, Artificial, Wastewater chemistry, Water Pollutants, Chemical analysis
- Abstract
The study investigates the efficiency of air-gap membrane distillation (AGMD) in water recovery and antibiotics removal from wastewater, focusing on high-concentration scenarios. Experimental findings reveal enhanced membrane performance with increasing the feed temperature, resulting in vapor permeate fluxes of up to 5 kg/m
2 .h at higher temperatures. Despite experiencing flux reduction caused by fouling from humic acid (HA) in the feed antibiotics solution, the antibiotics consistently maintain near-complete rejection rates (>99%) over 48 h. The foulant on the membrane surface was illustrated by SEM imaging. To know the temperature polarization and the fouling resistance, mathematical modeling was used, and it validates experimental results, elucidating temperature polarization effects and mass transfer coefficients. An increase in feed flow rates reduced thermal boundary layers, enhancing heat flux. Higher temperatures reduced HA fouling resistance. Therefore, AGMD proves effective in water recovery and antibiotics removal, with mathematical models aiding fouling understanding for future research and detailed computational fluid dynamics (CFD) models., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)- Published
- 2024
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8. Bioenzyme mediated hydrodistillation (BMHD) for extraction of mint oil from mentha leaves: improvement in yield and menthol content.
- Author
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Thakiyal S, Bhatia S, Kaur C, Phutela UG, Alam MS, and Sharma R
- Subjects
- Plant Oils chemistry, Mentha chemistry, Menthol chemistry, Plant Leaves chemistry, Distillation methods
- Abstract
The present study optimized pre-treatment conditions for bioenzyme-mediated hydro-distillation (BMHD) for extraction of mint oil from mentha leaves and the results were compared with those of traditional hydro-distillation (HD) method using response surface methodology. The bio-enzymes produced from moringa leaves had maximum pectinase activity (287.04 µg of sugar/min/ml) followed by xylanase (87.78 µg of sugar/min/ml) while endoglucanase, exoglucanase and amylase activities were comparatively low. The optimized conditions for HD were 69.08 temperature for 173.70 min with water:sample of 10.0. The optimized conditions for enzyme pre-treatment of mentha leaves by BMHD were enzyme concentration of 8%, for a period of 120 min at an incubation period of 40 ℃. The yield (%) and menthol content (%) of the oil at optimized conditions by HD were 1.55 ml/100 g of sample and 56.40% menthol content, respectively, and for BMHD the yield and menthol content (%) of the oil at optimized conditions were 3.69% and 72.80%, respectively. It was found that BMHD leads to a 130% increase in the yield of mint oil and a 10% increase in menthol content as compared to the HD method. No significant difference in physical parameters was observed in mint oil extracted via both methods. Therefore, BMHD is a cost-effective and sustainable approach having an edge over the HD method without compromising the quality and could be a viable approach for commercial purposes., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)
- Published
- 2024
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9. Prototype-based sample-weighted distillation unified framework adapted to missing modality sentiment analysis.
- Author
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Zhang Y, Liu F, Zhuang X, Hou Y, and Zhang Y
- Subjects
- Humans, Algorithms, Distillation methods, Neural Networks, Computer
- Abstract
Missing modality sentiment analysis is a prevalent and challenging issue in real life. Furthermore, the heterogeneity of multimodality often leads to an imbalance in optimization when attempting to optimize the same objective across all modalities in multimodal networks. Previous works have consistently overlooked the optimization imbalance of the network in cases when modalities are absent. This paper presents a Prototype-Based Sample-Weighted Distillation Unified Framework Adapted to Missing Modality Sentiment Analysis (PSWD). Specifically, it fuses features with a more efficient transformer-based cross-modal hierarchical cyclic fusion module. Subsequently, we propose two strategies, namely sample-weighted distillation and prototype regularization network, to address the issues of missing modality and optimization imbalance. The sample-weighted distillation strategy assigns higher weights to samples that are located closer to class boundaries. This facilitates the obtaining of complete knowledge by the student network from the teacher's network. The prototype regularization network calculates a balanced metric for each modality, which adaptively adjusts the gradient based on the prototype cross-entropy loss. Unlike conventional approaches, PSWD not only connects the sentiment analysis study in the missing modality to the full modality, but the proposed prototype regularization network is not reliant on the network structure and can be expanded to more multimodal studies. Massive experiments conducted on IEMOCAP and MSP-IMPROV show that our method achieves the best results compared to the latest baseline methods, which demonstrates its value for application in sentiment analysis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)
- Published
- 2024
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10. Innovative hyper-thermophilic aerobic submerged membrane distillation bioreactor for wastewater reclamation.
- Author
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Le HQ, Duong CC, Chang HM, Nguyen NC, Chien IC, Ngo HH, and Chen SS
- Subjects
- Phosphorus, Salinity, Membranes, Artificial, Water Purification methods, Aerobiosis, Ammonia analysis, Biomass, Temperature, Bioreactors, Wastewater chemistry, Distillation methods, Waste Disposal, Fluid methods
- Abstract
For the first time, a hyper-thermophilic aerobic (>60 °C) bioreactor has been integrated with direct submerged membrane distillation (MD), highlighting its potential as an advanced wastewater treatment solution. The hyper-thermophilic aerobic bioreactor, operating up to 65 °C, is tailored for high organic removal, while MD efficiently produces clean water. Throughout the study, high removal rates of 99.5% for organic matter, 96.4% for ammonia, and 100% for phosphorus underscored the impressive adaptability of microorganisms to challenging hyper-thermophilic conditions and a successful combination with the MD process. Despite the extreme temperatures and substantial salinity accumulation reaching up to 12,532 μS/cm, the biomass of microorganisms increased by 1.6 times over a 92-day period, representing their remarkable resilience. The distillation flux ranged from 6.15 LMH to 8.25 LMH, benefiting from the temperature gradient in the hyper-thermophilic setting and the design of the tubular submerged MD membrane module. The system also excels in pH control, utilizing fewer alkali and nutritional resources than conventional systems. Meiothermus, Firmicutes, and Bacteroidetes, the three dominant species, played a crucial role, showcasing their significance in adapting to high salinity and decomposing organic matter., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Crown Copyright © 2024. Published by Elsevier Ltd. All rights reserved.)
- Published
- 2024
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11. Ammonia recovery via direct contact membrane distillation: Modeling and performance optimization.
- Author
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Hu Y, Loh CY, Xie M, Chen G, Huang M, and Qiao J
- Subjects
- Waste Disposal, Fluid methods, Models, Theoretical, Hydrogen-Ion Concentration, Membranes, Artificial, Ammonia chemistry, Distillation methods, Wastewater chemistry
- Abstract
Ammonia recovery from wastewater has positive environmental benefits, avoiding eutrophication and reducing production energy consumption, which is one of the most effective ways to manage nutrients in wastewater. Specifically, ammonia recovery by membrane distillation has been gradually adopted due to its excellent separation properties for volatile substances. However, the global optimization of direct contact membrane distillation (DCMD) operating parameters to maximize ammonia recovery efficiency (ARE) has not been attempted. In this work, three key operating factors affecting ammonia recovery, i.e., feed ammonia concentration, feed pH, and DCMD running time, were identified from eight factors, by a two-level Plackett-Burman Design (PBD). Subsequently, Box-Behnken design (BBD) under the response surface methodology (RSM) was used to model and optimize the significant operating parameters affecting the recovery of ammonia though DCMD identified by PBD and statistically verified by analysis of variance (ANOVA). Results showed that the model had a high coefficient of determination value (R
2 = 0.99), and the interaction between NH4 Cl concentration and feed pH had a significant effect on ARE. The optimal operating parameters of DCMD as follows: NH4 Cl concentration of 0.46 g/L, feed pH of 10.6, DCMD running time of 11.3 h, and the maximum value of ARE was 98.46%. Under the optimized conditions, ARE reached up to 98.72%, which matched the predicted value and verified the validity and reliability of the model for the optimization of ammonia recovery by DCMD process., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)- Published
- 2024
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12. Influence of photothermal nanomaterials localization within the electrospun membrane structure on purification of saline oily wastewater based on photothermal vacuum membrane distillation.
- Author
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Ghodsi A and Fashandi H
- Subjects
- Vacuum, Graphite chemistry, Nanostructures chemistry, Distillation methods, Wastewater chemistry, Membranes, Artificial, Water Purification methods
- Abstract
Today, synergistic combination of special nanomaterials (NMs) and electrospinning technique has emerged as a promising strategy to address both water scarcity and energy concerns through the development of photothermal membranes for wastewater purification and desalination. This work was organized to provide a new perspective on membrane design for photothermal vacuum membrane distillation (PVMD) through optimizing membrane performance by varying the localization of photothermal NMs. Poly(vinylidene fluoride) omniphobic photothermal membranes were prepared by localizing graphene oxide nanosheets (GO NSh) (1) on the surface (0.2 wt%), (2) within the nanofibers structure (10 wt%) or (3) in both positions. Considering the case 1, after 7 min exposure to the 1 sun intensity light, the highest temperature (∼93.5 °C) was recorded, which is assigned to the accessibility of GO NSh upon light exposure. The case 3 yielded to a small reduction in surface temperature (∼90.4 °C) compared to the case 1, indicating no need to localize NMs within the nanofibers structure when they are localized on the surface. The other extreme belonged to the case 2 with the lowest temperature of ∼71.3 °C, which is consistent with the less accessibility of GO NSh during irradiation. It was demonstrated that the accessibility of photothermal NMs plays more pronounced role in the membrane surface temperature compared to the light trapping. However, benefiting from higher surface temperature during PVMD due to enhanced accessibility of photothermal NMs is balanced out by decrease in the permeate flux (case 1: 1.51 kg/m
2 h and case 2: 1.83 kg/m2 h) due to blocking some membrane surface pores by the binder. A trend similar to that for flux was also followed by the efficiency. Additionally, no change in rejection was observed for different GO NSh localizations., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)- Published
- 2024
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13. Comparative Analysis of Hydrosol Volatile Components of Citrus × Aurantium 'Daidai' and Citrus × Aurantium L. Dried Buds with Different Extraction Processes Using Headspace-Solid-Phase Microextraction with Gas Chromatography-Mass Spectrometry.
- Author
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Xie X, Xue H, Ma B, Guo X, Xia Y, Yang Y, Xu K, Li T, and Luo X
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- Terpenes analysis, Terpenes chemistry, Monoterpenes analysis, Monoterpenes isolation & purification, Odorants analysis, Distillation methods, Acetates, Gas Chromatography-Mass Spectrometry methods, Citrus chemistry, Solid Phase Microextraction methods, Volatile Organic Compounds analysis, Volatile Organic Compounds chemistry, Volatile Organic Compounds isolation & purification, Acyclic Monoterpenes analysis, Cyclohexane Monoterpenes analysis
- Abstract
This work used headspace solid-phase microextraction with gas chromatography-mass spectrometry (HS-SPME-GC-MS) to analyze the volatile components of hydrosols of Citrus × aurantium 'Daidai' and Citrus × aurantium L. dried buds (CAVAs and CADBs) by immersion and ultrasound-microwave synergistic-assisted steam distillation. The results show that a total of 106 volatiles were detected in hydrosols, mainly alcohols, alkenes, and esters, and the high content components of hydrosols were linalool, α-terpineol, and trans-geraniol. In terms of variety, the total and unique components of CAVA hydrosols were much higher than those of CADB hydrosols; the relative contents of 13 components of CAVA hydrosols were greater than those of CADB hydrosols, with geranyl acetate up to 15-fold; all hydrosols had a citrus, floral, and woody aroma. From the pretreatment, more volatile components were retained in the immersion; the relative contents of linalool and α-terpineol were increased by the ultrasound-microwave procedure; and the ultrasound-microwave procedure was favorable for the stimulation of the aroma of CAVA hydrosols, but it diminished the aroma of the CADB hydrosols. This study provides theoretical support for in-depth exploration based on the medicine food homology properties of CAVA and for improving the utilization rate of waste resources.
- Published
- 2024
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14. Profiling of seized Cannabis sativa L. flowering tops by means of microwave-assisted hydro distillation and gas chromatography analyses.
- Author
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Micalizzi G, Cucinotta L, Chiaia V, Alibrando F, Cannizzaro F, Branca G, Maida P, Oliveri P, Mondello L, and Sciarrone D
- Subjects
- Terpenes analysis, Dronabinol analysis, Chromatography, Gas methods, Microwaves, Cannabis chemistry, Distillation methods, Flowers chemistry, Gas Chromatography-Mass Spectrometry methods, Oils, Volatile analysis, Oils, Volatile chemistry
- Abstract
This research aimed to support police forces in their battle against illicit drug trafficking by means of a multi-technique approach, based on gas chromatography. In detail, this study was focused on the profiling of volatile substances in narcotic Cannabis sativa L. flowering tops. For this purpose, the Scientific Investigation Department, RIS Carabinieri of Messina, provided 25 seized samples of Cannabis sativa L. The content of Δ
9 -tetrahydrocannabinol (THC), useful to classify cannabis plant as hemp (≤ 0.2 %) or as marijuana (> 0.2 %), was investigated. Essential oils of illicit drug samples were extracted using a microwave-assisted hydro-distillation (MAHD) system; GC-MS and GC-FID analytical techniques were used for the characterization of the terpenes and terpenoids fingerprint. Furthermore, the enantiomeric and carbon isotopic ratios of selected chiral compounds were investigated using a heart-cutting multidimensional GC (MDGC) approach. The latter exploited a combination of an apolar column in the first dimension, and a chiral cyclodextrin-based column in the second one, prior to parallel isotope-ratio mass spectrometry (C-IRMS) and MS detection. Finally, all the data were gathered into a statistical model, to demonstrate the existence of useful parameters to be used for the classification of seized samples., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)- Published
- 2024
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15. Comparison of quantity, quality and antibacterial activity of essential oil Mentha longifolia (L.) L. under different traditional and modern extraction methods.
- Author
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Karimnejad M and Ghavam M
- Subjects
- Gas Chromatography-Mass Spectrometry, Distillation methods, Bacteria drug effects, Plant Extracts pharmacology, Plant Extracts chemistry, Chromatography, Supercritical Fluid methods, Plant Oils pharmacology, Plant Oils chemistry, Oils, Volatile pharmacology, Oils, Volatile chemistry, Mentha chemistry, Anti-Bacterial Agents pharmacology, Microbial Sensitivity Tests
- Abstract
Extraction is the first and most important step in obtaining the effective ingredients of medicinal plants. Mentha longifolia (L.) L. is of considerable economic importance as a natural raw material for the food and pharmaceutical industries. Since the effect of different extraction methods (traditional and modern methods) on the quantity, quality and antimicrobial activity of the essential oil of this plant has not been done simultaneously; the present study was designed for the first time with the aim of identifying the best extraction method in terms of these features. For this purpose, extracting the essential oil of M. longifolia with the methods of hydrodistillation with Clevenger device (HDC), steam distillation with Kaiser device (SDK), simultaneous distillation with a solvent (SDE), hydrodistillation with microwave device (HDM), pretreatment of ultrasonic waves and Clevenger (U+HDC) and supercritical fluid (SF) were performed. Chemical compounds were identified by gas chromatography coupled with mass spectrometer (GC-MS). Antimicrobial activity of essential oils against various clinical microbial strains was evaluated by agar diffusion method and determination of the minimum inhibitory concentration and minimum bactericidal concentration (MIC and MBC). The results showed that the highest and lowest yields of M. longifolia leaf essential oil belonged to HDC (1.6083%) and HDM (0.3416%). The highest number of compounds belonged to SDK essential oil and was equal to 72 compounds (with a relative percentage of 87.13%) and the lowest number of compounds was related to the SF essential oil sample (7 compounds with a relative percentage of 100%). Piperitenone (25.2-41.38%), piperitenone oxide (22.02-0%), pulegone (10.81-0%) and 1,8-cineole (5-35.0%) are the dominant and main components of M. longifolia essential oil were subjected to different extraction methods. Antimicrobial activity results showed that the lowest MIC value belonged to essential oils extracted by HDM, SDK, SDE and U+HDC methods with a value of 1000 μg/mL was observed against Gram-negative bacteria Shigella dysenteriae, which was 5 times weaker than rifampin and 7 times weaker than gentamicin. Therefore, it can be concluded that in terms of efficiency of the HDC method, in terms of the percentage of compounds of the HDM method, and in terms of microbial activity, the SDK, HDM and U+HDC methods performed better., Competing Interests: NO authors have competing interests., (Copyright: © 2024 Karimnejad, Ghavam. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
- Published
- 2024
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16. Progress in membrane distillation processes for dye wastewater treatment: A review.
- Author
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Nthunya LN, Chong KC, Lai SO, Lau WJ, López-Maldonado EA, Camacho LM, Shirazi MMA, Ali A, Mamba BB, Osial M, Pietrzyk-Thel P, Pregowska A, and Mahlangu OT
- Subjects
- Water Purification methods, Industrial Waste, Wastewater chemistry, Distillation methods, Coloring Agents chemistry, Coloring Agents isolation & purification, Waste Disposal, Fluid methods, Membranes, Artificial, Water Pollutants, Chemical chemistry, Water Pollutants, Chemical analysis, Textile Industry
- Abstract
Textile and cosmetic industries generate large amounts of dye effluents requiring treatment before discharge. This wastewater contains high levels of reactive dyes, low to none-biodegradable materials and chemical residues. Technically, dye wastewater is characterised by high chemical and biological oxygen demand. Biological, physical and pressure-driven membrane processes have been extensively used in textile wastewater treatment plants. However, these technologies are characterised by process complexity and are often costly. Also, process efficiency is not achieved in cost-effective biochemical and physical treatment processes. Membrane distillation (MD) emerged as a promising technology harnessing challenges faced by pressure-driven membrane processes. To ensure high cost-effectiveness, the MD can be operated by solar energy or low-grade waste heat. Herein, the MD purification of dye wastewater is comprehensively and yet concisely discussed. This involved research advancement in MD processes towards removal of dyes from industrial effluents. Also, challenges faced by this process with a specific focus on fouling are reviewed. Current literature mainly tested MD setups in the laboratory scale suggesting a deep need of further optimization of membrane and module designs in near future, especially for textile wastewater treatment. There is a need to deliver customized high-porosity hydrophobic membrane design with the appropriate thickness and module configuration to reduce concentration and temperature polarization (CP and TP). Also, energy loss should be minimized while increasing dye rejection and permeate flux. Although laboratory experiments remain pivotal in optimizing the MD process for treating dye wastewater, the nature of their time intensity poses a challenge. Given the multitude of parameters involved in MD process optimization, artificial intelligence (AI) methodologies present a promising avenue for assistance. Thus, AI-driven algorithms have the potential to enhance overall process efficiency, cutting down on time, fine-tuning parameters, and driving cost reductions. However, achieving an optimal balance between efficiency enhancements and financial outlays is a complex process. Finally, this paper suggests a research direction for the development of effective synthetic and natural dye removal from industrially discharged wastewater., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)
- Published
- 2024
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17. Contrasting mixed scaling patterns and mechanisms of nanofiltration and membrane distillation.
- Author
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Zheng L, Wu Q, Ulbricht M, Zhong H, Duan N, Van der Bruggen B, and Wei Y
- Subjects
- Water Purification methods, Salinity, Wastewater chemistry, Distillation methods, Membranes, Artificial, Filtration
- Abstract
Oriented towards the pressing needs for hypersaline wastewater desalination and zero liquid discharge (ZLD), the contrasting mixed scaling of thermal-driven vacuum membrane distillation (VMD) and pressure-driven nanofiltration (NF) were investigated in this work. Bulk crystallization was the main mechanism in VMD due to the high salinity and temperature, but the time-independent resistance by the adsorption of silicate and organic matter dominated the initial scaling process. Surface crystallization and the consequent pore-blocking were the main scaling mechanisms in NF, with the high permeate drag force, hydraulic pressure, and cross-flow rate resulting in the dense scaling layer mainly composed of magnesium-silica hydrate (MSH). Silicate enhanced NF scaling with a 75% higher initial flux decline rate attributed to the MSH formation and compression, but delayed bulk crystallization in VMD. Organic matter presented an anti-scaling effect by delaying bulk crystallization in both VMD and NF, but specifically promoted CaCO
3 scaling in NF. Furthermore, the incipient scaling was intensified as silicate and organic matter coexisted. The scaling mechanism shifted from surface to bulk crystallization due to the membrane concentration in both VMD and NF. This work fills the research gaps on mixed scaling mechanisms in different membrane processes, which offers insights for scaling mitigation and thereby supports the application of ZLD., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)- Published
- 2024
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18. THE INFLUENCE OF DISTILLATION METHODS ON THE FLAVOR PROFILE AND QUALITY INDICES OF WINE BRANDIES
- Author
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BALANUȚA, Anatol, COVACI, Ecaterina, and SCLIFOS, Aliona
- Subjects
aroma compounds ,distillation methods ,grape varieties ,physico-chemical indices wine distillates ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Electronic computers. Computer science ,QA75.5-76.95 - Abstract
The article examines the geographical area delimited for the production of the Divine and the specific characteristics and physical-geographical conditions of the Călărași vineyard through the prism of different methods of distillation and production of wine distillates. Technological regimes for distilling wine raw materials and organoleptic and physico-chemical indices such as: alcohol content, optical density, pH, aldehyde content, higher alcohol content and volatile acid content are scientifically argued. The quality indicators were determined for both wines and distillates obtained at the 'Charente' batch plant and the 'VAND-M-0' plant. The impact of the distillation method on the quality and production process of the wine distillate is evaluated.
- Published
- 2021
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19. Helichrysum italicum: From Extraction, Distillation, and Encapsulation Techniques to Beneficial Health Effects
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Veronika Furlan and Urban Bren
- Subjects
Helichrysum italicum ,polyphenolic compounds ,biological effects ,extraction methods ,distillation methods ,encapsulation methods ,Chemical technology ,TP1-1185 - Abstract
Helichrysum italicum (family Asteraceae), due to its various beneficial health effects, represents an important plant in the traditional medicine of Mediterranean countries. Currently, there is a renewed interest in this medicinal plant, especially in investigations involving the isolation and identification of its bioactive compounds from extracts and essential oils, as well as in experimental validation of their pharmacological activities. In this paper, we review the current knowledge on the beneficial health effects of Helichrysum italicum extracts, essential oils, and their major bioactive polyphenolic compounds, ranging from antioxidative, anti-inflammatory, and anticarcinogenic activities to their antiviral, antimicrobial, insecticidal, and antiparasitic effects. This review also provides an overview of the most promising extraction and distillation techniques for obtaining high-quality extracts and essential oils from Helichrysum italicum, as well as methods for determining their antioxidative, antimicrobial, anti-inflammatory, and anticarcinogenic activities. Finally, new ideas for in silico studies of molecular mechanisms of bioactive polyphenols from Helichrysum italicum, together with novel suggestions for their improved bioavailability through diverse encapsulation techniques, are introduced.
- Published
- 2023
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20. Essential Oil Variability of Azorean Cryptomeria japonica Leaves under Different Distillation Methods, Part 1: Color, Yield and Chemical Composition Analysis.
- Author
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Arruda, Filipe, Rosa, José S., Rodrigues, Ana, Oliveira, Luísa, Lima, Ana, Barroso, José G., and Lima, Elisabete
- Subjects
ESSENTIAL oils ,CRYPTOMERIA japonica ,ANALYTICAL chemistry ,CHEMICAL yield ,DISTILLATION ,MONOTERPENES - Abstract
This study mainly deals with the effect of hydrodistillation (HD) and water-steam distillation (WSD) methods on the color, yield, and chemical profile of the essential oil (EO) from Cryptomeria japonica fresh leaves from São Miguel Island (Azores Archipelago, Portugal). The yields of EO–HD (pale-yellowish) and EO–WSD (colorless) samples were 1.21% and 0.45% (v/w), respectively. The GC–FID, GC–MS, and
13 C-NMR analyses of EO–HD vs. EO–WSD revealed (i) a high-content of monoterpenes (72.8% vs. 86.7%), mainly α-pinene (34.5% vs. 46.4%) and sabinene (20.2% vs. 11.6%), and oxygenated mono- and sesquiterpenes (20.2% vs. 9.6%); (ii) similar sesquiterpene (1.6% vs. 1.6%), β-myrcene (5.9% vs. 5.8%), and camphene (3.5% vs. 3.8%) contents; and (iii) significant differences in other classes/components: EO–HD is richer in oxygenated sesquiterpenes (17.1%, mainly elemol (10.4%) and α-eudesmol (3.4%)) and diterpenes (3%; mostly phyllocladene), while EO–WSD is richer in oxygenated monoterpenes (7.2%, mainly terpinen-4-ol (5.4%)), p-cymene (4.4%), and limonene (3.2%). Overall, the color, yield, and quantitative composition of the EO samples studied are strongly influenced by the distillation method. Nonetheless, this C. japonica leaf EO displayed a consistent α-pinene- and sabinene-rich composition. The same chemotype was found in a commercial Azorean C. japonica leaf EO sample, obtained by industrial steam distillation (SD), as well as in Corsica C. japonica leaf EO–HD. Furthermore, the bioactive composition of our EO samples revealed the potential to be used in green plant protection and in the medical, food, cosmetic, and household industries. [ABSTRACT FROM AUTHOR]- Published
- 2022
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21. Cross-modal knowledge distillation for continuous sign language recognition.
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Gao L, Shi P, Hu L, Feng J, Zhu L, Wan L, and Feng W
- Subjects
- Humans, Neural Networks, Computer, Distillation methods, Sign Language, Deep Learning
- Abstract
Continuous Sign Language Recognition (CSLR) is a task which converts a sign language video into a gloss sequence. The existing deep learning based sign language recognition methods usually rely on large-scale training data and rich supervised information. However, current sign language datasets are limited, and they are only annotated at sentence-level rather than frame-level. Inadequate supervision of sign language data poses a serious challenge for sign language recognition, which may result in insufficient training of sign language recognition models. To address above problems, we propose a cross-modal knowledge distillation method for continuous sign language recognition, which contains two teacher models and one student model. One of the teacher models is the Sign2Text dialogue teacher model, which takes a sign language video and a dialogue sentence as input and outputs the sign language recognition result. The other teacher model is the Text2Gloss translation teacher model, which targets to translate a text sentence into a gloss sequence. Both teacher models can provide information-rich soft labels to assist the training of the student model, which is a general sign language recognition model. We conduct extensive experiments on multiple commonly used sign language datasets, i.e., PHOENIX 2014T, CSL-Daily and QSL, the results show that the proposed cross-modal knowledge distillation method can effectively improve the sign language recognition accuracy by transferring multi-modal information from teacher models to the student model. Code is available at https://github.com/glq-1992/cross-modal-knowledge-distillation_new., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)
- Published
- 2024
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22. Membrane electrolysis distillation for volatile fatty acids extraction from pH-neutral fermented wastewater.
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Lu S, McGaughey A, Im S, Liu Y, Wang X, Leininger A, Jassby D, Hoek E, and Ren ZJ
- Subjects
- Hydrogen-Ion Concentration, Membranes, Artificial, Waste Disposal, Fluid methods, Fatty Acids, Volatile, Wastewater chemistry, Distillation methods, Electrolysis, Fermentation
- Abstract
Volatile fatty acids (VFAs) serve as building blocks for a wide range of chemicals, but it is difficult to extract VFAs from pH-neutral wastewater using evaporation methods because of the ionized form. This study presents a new membrane electrolysis distillation (MED) process that extracts VFAs from such fermentation solutions. MED uniquely integrates pH regulation and joule heating to facilitate the efficient evaporation of VFAs. This integration occurs alongside a hydrophobic membrane that ensures effective gas-liquid phase separation. Operating solely on electricity, MED achieved an acid flux rate of 12.03 g/m
2 /h at 6V. In contrast, the control results without the joule heating or pH swing only obtained a 0.23 g/m2 /h and 0.32 g/m2 /h flux, respectively. In addition, a physicochemical model was developed to assess the impacts of temperature on membrane surface pH. This system enhances resource recovery from waste streams and helps achieve a circular carbon economy., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2024. Published by Elsevier Ltd.)- Published
- 2024
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23. Lightweight CNN combined with knowledge distillation for the accurate determination of black tea fermentation degree.
- Author
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Ding Z, Yang C, Hu B, Guo M, Li J, Wang M, Tian Z, Chen Z, and Dong C
- Subjects
- Distillation methods, Camellia sinensis chemistry, China, Fermentation, Tea chemistry, Neural Networks, Computer
- Abstract
Black tea is the second most common type of tea in China. Fermentation is one of the most critical processes in its production, and it affects the quality of the finished product, whether it is insufficient or excessive. At present, the determination of black tea fermentation degree completely relies on artificial experience. It leads to inconsistent quality of black tea. To solve this problem, we use machine vision technology to distinguish the degree of fermentation of black tea based on images, this paper proposes a lightweight convolutional neural network (CNN) combined with knowledge distillation to discriminate the degree of fermentation of black tea. After comparing 12 kinds of CNN models, taking into account the size of the model and the performance of discrimination, as well as the selection principle of teacher models, Shufflenet_v2_x1.0 is selected as the student model, and Efficientnet_v2 is selected as the teacher model. Then, CrossEntropy Loss is replaced by Focal Loss. Finally, for Distillation Loss ratios of 0.6, 0.7, 0.8, 0.9, Soft Target Knowledge Distillation (ST), Masked Generative Distillation (MGD), Similarity-Preserving Knowledge Distillation (SPKD), and Attention Transfer (AT) four knowledge distillation methods are tested for their performance in distilling knowledge from the Shufflenet_v2_x1.0 model. The results show that the model discrimination performance after distillation is the best when the Distillation Loss ratio is 0.8 and the MGD method is used. This setup effectively improves the discrimination performance without increasing the number of parameters and computation volume. The model's P, R and F1 values reach 0.9208, 0.9190 and 0.9192, respectively. It achieves precise discrimination of the fermentation degree of black tea. This meets the requirements of objective black tea fermentation judgment and provides technical support for the intelligent processing of black tea., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)
- Published
- 2024
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24. Surface energy-induced anti-wetting and anti-fouling enhancement of Janus membrane for membrane distillation.
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Meng L, Chen X, Cai T, Tong X, and Wang Z
- Subjects
- Water Purification methods, Wettability, Polyvinyls chemistry, Hydrophobic and Hydrophilic Interactions, Biofouling prevention & control, Indoles chemistry, Polymers chemistry, Fluorocarbon Polymers, Membranes, Artificial, Distillation methods
- Abstract
Membrane distillation (MD) presents a promising alternative to conventional desalination systems, particularly for the treatment of hypersaline wastewater. However, the large-scale application of MD is hindered by challenges such as membrane wetting, membrane fouling, and low permeate flux. Herein, we proposed an air/liquid interface deposition method to fabricate a Janus membrane, termed the PVDF-PDA/PEI-Si membrane. The membrane featured a nanosieving, superhydrophilic polydopamine/polyethylenimine (PDA/PEI) layer decorated with silica nanoparticles, coupled with a microporous, hydrophobic polyvinylidene fluoride (PVDF) layer. The introduction of a dense PDA/PEI-Si layer featuring high surface energy significantly enhanced the wetting and fouling resistance of the membrane, with a minor effect on the permeate flux. The performance enhancement was particularly evident when hypersaline water containing sodium dodecyl sulfate (SDS) and oily contaminants was used as the feed. The interactions between the membrane and contaminants were calculated using the XDLVO theory and molecular dynamics simulations to elucidate the mechanisms underlying the enhanced anti-wetting and anti-fouling properties, respectively. According to the XDLVO theory, a large energy barrier must be overcome for the SDS to attach onto the PDA/PEI-Si surface. Meanwhile, molecular dynamics simulations confirmed the weak interaction energy between the oily foulants and the PVDF-PDA/PEI-Si membrane due to its high surface energy. This study presents a promising approach for the fabrication of high-performance MD membranes and provides new insights into the mechanisms underlying the enhanced anti-wetting and anti-fouling properties., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)
- Published
- 2024
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25. Crosslinking and fluorination reinforced PTFE nanofibrous membrane with excellent amphiphobic performance for low-scaling membrane distillations.
- Author
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Liu Y, Meng Z, Zou R, Zhu L, Wang X, and Zhu M
- Subjects
- Halogenation, Water Purification methods, Polytetrafluoroethylene chemistry, Nanofibers chemistry, Membranes, Artificial, Distillation methods
- Abstract
Membrane distillation (MD) has emerged as a promising technology for desalination and concentration of hypersaline brine. However, the efficient preparation of a structurally stable and salinity-resistant membrane remains a significant challenge. In this study, an amphiphobic polytetrafluoroethylene nanofibrous membrane (PTFE NFM) with exceptional resistance to scaling has been developed, using an energy-efficient method. This innovative approach avoids the high-temperature sintering treatment, only involving electrospinning with PTFE/PVA emulsion and subsequent low-temperature crosslinking and fluorination. The impact of the PVA and PTFE contents, as well as the crosslinking and subsequent fluorination on the morphology and MD performance of the NFM, were systematically investigated. The optimized PTFE NFM displayed robust amphiphobicity, boasting a water contact angle of 155.2º and an oil contact angle of 132.7º. Moreover, the PTFE NFM exhibited stable steam flux of 52.1 L·m
-2 ·h-1 and 26.7 L·m-2 ·h-1 when fed with 3.5 wt % and 25.0 wt % NaCl solutions, respectively, and an excellent salt rejection performance (99.99 %, ΔT = 60 °C) in a continuous operation for 24 h, showing exceptional anti-scaling performance. It also exhibited stable anti-wetting and anti-fouling properties against surfactants (sodium dodecyl sulfate) and hydrophobic contaminants (diesel oil). These results underscore the significant potential of the PTFE nanofibrous membrane for practical applications in desalination, especially in hypersaline or polluted aqueous environments., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)- Published
- 2024
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26. Investigation of direct contact membrane distillation (DCMD) performance using CFD and machine learning approaches.
- Author
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Abrofarakh M, Moghadam H, and Abdulrahim HK
- Subjects
- Hydrodynamics, Models, Theoretical, Porosity, Temperature, Distillation methods, Machine Learning, Membranes, Artificial, Neural Networks, Computer, Water Purification methods
- Abstract
Direct Contact Membrane Distillation (DCMD) is emerging as an effective method for water desalination, known for its efficiency and adaptability. This study delves into the performance of DCMD by integrating two powerful analytical tools: Computational Fluid Dynamics (CFD) and Artificial Neural Networks (ANN). The research thoroughly examines the impact of various factors, such as inlet temperatures, velocities, channel heights, salt concentration, and membrane characteristics, on the process's efficiency, specifically calculating the water vapor flux. A rigorous validation of the CFD model aligns well with established studies, ensuring reliability. Subsequently, over 1000 data points reflecting variations in input factors are utilized to train and validate the ANN. The training phase demonstrated high accuracy, with near-zero mean squared errors and R
2 values close to one, indicating a strong predictive capability. Further analysis post-ANN training shed light on key relationships: higher membrane porosity boosts water vapor flux, whereas thicker membranes reduce it. Additionally, it was detailed how salt concentration, channel dimensions, inlet temperatures, and velocities significantly influence the distillation process. Finally, a mathematical model was proposed for water vapor flux as a function of key input factors. The results highlighted that salt mole fraction and hot water inlet temperature have the most effect on the water vapor flux. This comprehensive investigation contributes to the understanding of DCMD and emphasizes the potential of combining CFD and ANN for optimizing and innovating water desalination technology., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)- Published
- 2024
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27. Membrane distillation assisting food production processes of thermally sensitive food liquid items: a review.
- Author
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Gontarek-Castro E and Castro-Muñoz R
- Subjects
- Membranes, Artificial, Dairy Products analysis, Hot Temperature, Ethanol chemistry, Fruit and Vegetable Juices analysis, Distillation methods, Food Handling methods
- Abstract
Physical separation technologies have become important tool for processing in the current food manufacturing industries, especially for the products containing bioactive compounds thanks to their health benefits in costumers. As for the processing of bioactive food ingredients implies the implementation of integrated systems oriented to their separation, fractionation, and recovery. In this field, membrane distillation (MD), which is a thermally driven membrane process, has been proposed as an alternative for the separation and concentration of liquid food items. In principle, MD can separate water and volatile compounds from aqueous feed solutions through a permeate that passes across microporous hydrophobic membranes. The separation via MD is thanks to the vapor pressure difference on both membrane sides. In this review, we analyzed the ongoing experimental efforts aimed to recover and purify food bioactive compounds from the concentration of fruit juices and extracts using MD. Also, the processing of dairy products, concentration of food by-products, and ethanol production and its removal from beverages using MD have been reviewed. Additionally, a feedback on the distinct membrane module configurations and membrane requirements for successful operation is addressed.
- Published
- 2024
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28. Steam distillation process for flavor enhancement of milk coffee: Effects of condensation temperature on volatile compounds and flavor characteristics.
- Author
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Shinichiro H, Masayuki A, Takuya Y, Daisho Y, Atsushige F, Kana T, Miki M, Mito K, and Yutaka K
- Subjects
- Humans, Animals, Milk chemistry, Temperature, Coffea chemistry, Female, Consumer Behavior, Flavoring Agents analysis, Hot Temperature, Principal Component Analysis, Adult, Odorants analysis, Male, Volatile Organic Compounds analysis, Coffee chemistry, Taste, Distillation methods, Steam, Gas Chromatography-Mass Spectrometry methods, Food Handling methods
- Abstract
To enhance the flavor characteristics of milk coffee, steam distillation was applied to roasted ground coffee to obtain extracts that were then added to the hot water extract of the residue. The effects of different condensation temperatures for steam distillation on the volatile compounds of condensates and the flavor characteristics of the milk coffees prepared with each condensate were investigated. The volatile compounds were analyzed by gas chromatography/mass spectrometry, and principal component analysis (PCA) was performed on the mean peak areas of the volatiles that showed significant differences between the samples. The five types of milk coffees prepared with/without condensates were evaluated by consumer panelists using the check-all-that-apply question combined with the milk coffee flavor lexicon. The results showed that the concentration of volatile compounds tended to be higher in response to decreasing condensation temperature in steam distillation. The volatile compounds were grouped into four patterns based on their concentration in the condensates, which was affected by the volatility of the compounds and the duration of the condensation process in steam distillation. PCA clarified the characteristic volatile compounds that contribute to differences between the three condensates. The check-all-that-apply results indicated that the samples prepared with the condensates enhanced some specific coffee flavors, although acceptances for them were not enhanced. Implementing a steam distillation step in the milk coffee production process could lead to enhancing the coffee flavor strength of milk coffee products, and changing the condensation temperature for steam distillation was effective for providing different flavor characteristics of milk coffee. PRACTICAL APPLICATION: Changing the condensation temperature for steam distillation is effective in differentiating the flavor characteristics of milk coffee. Increasing the condensation temperature resulted in decreased concentrations of volatile compounds, which enhanced the milk and rich flavor. Decreasing the condensation temperature resulted in increased concentrations of volatile compounds, which provided a stronger coffee flavor to the milk coffee, possibly leading to a reduction in the use of coffee for milk coffee production. The check-all-that-apply question combined with the milk coffee flavor lexicon could effectively evaluate consumers' perceptions of the milk coffee flavor characteristics and their acceptances in a single survey., (© 2024 Institute of Food Technologists.)
- Published
- 2024
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29. Treatment of tequila distillation volatile residues by electrochemical oxidation using titanium electrodes.
- Author
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Martínez-Orozco E, Nápoles-Armenta J, Gortáres-Moroyoqui P, Santiago-Olivares N, Ulloa-Mercado RG, De la Mora-Orozco C, Leyva-Soto LA, Alvarez-Valencia LH, Meza-Escalante ER, and Rentería-Mexia AM
- Subjects
- Electrochemical Techniques methods, Alcoholic Beverages analysis, Industrial Waste analysis, Waste Disposal, Fluid methods, Mexico, Oxidation-Reduction, Titanium chemistry, Distillation methods, Electrodes, Volatile Organic Compounds chemistry
- Abstract
ABSTRACT Tequila production occurs in Mexico's designated area of origin, principally in the Jalisco State. Its residues are a challenge in treatment and tracking due to a lack of technology, non-economic treatments available, low environmental consciousness and incipient control from authorities. In 2021, average production was close to 1.5 million tequila litres per day with an estimated residue yield of 10-12 litres of stillage (tequila vinasses) per tequila litre produced, including volatile fractions. This research aims to reduce organic matter by electrooxidation (EO) from 5 distillation volatile residual effluents (two-stage still distillation) from three tequila distilleries, first and second-stage heads and heads and tails and second-stage non-evaporated fraction. Round 3 mm titanium (grade-1) electrodes (one anode and one cathode) were used, with fixed voltage to a value of 30 VDC at 0, 3, 6, 9 and 12 h with 75 experiments. Gas chromatography was used to analyse methanol, ethanol, acetaldehyde, ethyl acetate, n-propanol, sec-butanol, iso-butanol, n-butanol, iso-amyl, n-amyl, and ethyl lactate content. Treatment shows positive results, reducing organic matter content in all effluents in a Chemical Oxygen Demand COD range of 580-1880 mg/L.h, particularly useful in the second-stage non-evaporated fraction for water recovery.HIGHLIGHTSResidual effluent treatment is beneficial to environmental and resource sustainability.Process without adding materials achieving cleaner treated effluents.Process aimed as the final step to recover water.This process could help the Tequila industry to reach a higher sustainability level by reducing water usage and untreated residues.
- Published
- 2024
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30. Exploiting the potential of a novel "in-situ latent heat recovery" in hollow-fiber vacuum membrane distillation process for simultaneously improved water production and energy efficiency.
- Author
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Liu Z, Lu X, Wu C, Gu J, and Wu Q
- Subjects
- Vacuum, Water Purification methods, Wastewater chemistry, Water chemistry, Distillation methods, Hot Temperature, Membranes, Artificial
- Abstract
Thermal driven membrane distillation (MD) technology is a promising method for purifying & recovering various salty (especially high salty) or contaminated wastewaters with low-grade heat sources. However, the drawbacks of "high energy consumption" and "high cooling water consumption" pose special challenges for the future development of this technology. In this article, we report an innovative strategy called "in-situ heat transfer", which is based on the jacketed structure composed of hollow fiber membranes and capillary heat exchange tubes, to simplify the migration steps of condensation latent heat in MD heat recovery process. The results indicate that the novel heat recovery strategy exhibits higher growth rates both in the flux and gained output ratio (47.4 % and 173.1 %, respectively), and further reduces the system's dependence on cooling water. In sum, under the control of the "in-situ heat transfer" mechanism, the functional coupling of "vapor condensation (exothermic)" and "feed evaporation (endothermic)" in limited-domain space is an attractive alternative solution, because it eliminates the disadvantages of the imbalance between heat supply and demand in traditional heat recovery methods. Our research may facilitate the development of MD heat recovery modules for industrial applications, which will help to further achieve the goal of energy saving and emission reduction., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)
- Published
- 2024
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31. A novel electro-Fenton hybrid system for enhancing the interception of volatile organic compounds in membrane distillation desalination.
- Author
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Liu H, Li K, Wang K, Wang Z, Liu Z, Zhu S, Qu D, Zhang Y, and Wang J
- Subjects
- Distillation methods, Membranes, Artificial, Phenols, Volatile Organic Compounds, Water Purification methods
- Abstract
Membrane distillation (MD) is a promising alternative desalination technology, but the hydrophobic membrane cannot intercept volatile organic compounds (VOCs), resulting in aggravation in the quality of permeate. In term of this, electro-Fenton (EF) was coupled with sweeping gas membrane distillation (SGMD) in a more efficient way to construct an advanced oxidation barrier at the gas-liquid interface, so that the VOCs could be trapped in this layer to guarantee the water quality of the distillate. During the so-called EF-MD process, an interfacial interception barrier containing hydroxyl radical formed on the hydrophobic membrane surface. It contributed to the high phenol rejection of 90.2% with the permeate phenol concentration lower than 1.50 mg/L. Effective interceptions can be achieved in a wide temperature range, even though the permeate flux of phenol was also intensified. The EF-MD system was robust to high salinity and could electrochemically regenerate ferrous ions, which endowed the long-term stability of the system. This novel EF-MD configuration proposed a valuable strategy to intercept VOCs in MD and will broaden the application of MD in hypersaline wastewater treatment., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this article., (Copyright © 2023. Published by Elsevier B.V.)
- Published
- 2024
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32. Effects of mutant yeast strain and distillation method on sensory characteristics and volatile compounds in Korean distilled spirit, soju.
- Author
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Chin, Young-Wook, Yu, Hwan Hee, Kang, Sunhee, and Kim, Tae-Wan
- Subjects
- *
DISTILLATION , *ATMOSPHERIC pressure , *WEATHER , *SACCHAROMYCES cerevisiae , *MASS spectrometry , *SOLID phase extraction - Abstract
The effects of mutant yeast and distillation method on volatile compounds and sensory characteristics of the Korean distilled soju were investigated. Saccharomyces cerevisiae 88–4 and its 5,5,5-trifluoro- dl -leucine (TFL)-resistant mutant GNIA2 were used for brewing and distilling under atmospheric and vacuum conditions for manufacturing soju. The volatiles in the soju were comparatively analyzed by semi-quantification using solid-phase microextraction-gas chromatography/mass spectrometry. The mutant strain led to an increase in 9 volatiles and a decrease in 4 volatiles in distilled soju. Considering the threshold, ethyl caproate, ethyl caprylate, ethyl caprate, isoamyl caprylate, ethyl laurate, isoamyl acetate, and isoamyl alcohol might contribute to the enhanced fruity, floral, and sweet flavors in distilled soju. Meanwhile, higher alcohols and esters were 15% and 250% higher in atmospheric distillation than in vacuum distillation. The difference in flavor component, especially, esters content may contribute to the flavor of soju distilled at atmospheric pressure. Comparing the effects of yeast and distillation method on volatile contents, yeast had a greater effect on higher alcohol content, while distillation method had a greater effect on ester content. These results showed that the quality of soju can be diversified by combining mutant yeast with appropriate distillation methods. • The mutant yeast led to an increase in 11 volatiles and a decrease in 4 volatiles. • Seven volatiles might contribute to the flavor of distilled soju. • Most volatiles were higher in atmospheric distillation than in vacuum distillation. • Esters content may contribute to the flavor of atmospheric distilled soju. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
33. Essential Oil Variability of Azorean Cryptomeriajaponica Leaves under Different Distillation Methods, Part 1: Color, Yield and Chemical Composition Analysis
- Author
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Filipe Arruda, José S. Rosa, Ana Rodrigues, Luísa Oliveira, Ana Lima, José G. Barroso, and Elisabete Lima
- Subjects
circular bioeconomy ,woody waste biovalorization ,Japanese cedar ,distillation methods ,essential oil ,terpenes/terpenoids ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
This study mainly deals with the effect of hydrodistillation (HD) and water-steam distillation (WSD) methods on the color, yield, and chemical profile of the essential oil (EO) from Cryptomeria japonica fresh leaves from São Miguel Island (Azores Archipelago, Portugal). The yields of EO–HD (pale-yellowish) and EO–WSD (colorless) samples were 1.21% and 0.45% (v/w), respectively. The GC–FID, GC–MS, and 13C-NMR analyses of EO–HD vs. EO–WSD revealed (i) a high-content of monoterpenes (72.8% vs. 86.7%), mainly α-pinene (34.5% vs. 46.4%) and sabinene (20.2% vs. 11.6%), and oxygenated mono- and sesquiterpenes (20.2% vs. 9.6%); (ii) similar sesquiterpene (1.6% vs. 1.6%), β-myrcene (5.9% vs. 5.8%), and camphene (3.5% vs. 3.8%) contents; and (iii) significant differences in other classes/components: EO–HD is richer in oxygenated sesquiterpenes (17.1%, mainly elemol (10.4%) and α-eudesmol (3.4%)) and diterpenes (3%; mostly phyllocladene), while EO–WSD is richer in oxygenated monoterpenes (7.2%, mainly terpinen-4-ol (5.4%)), p-cymene (4.4%), and limonene (3.2%). Overall, the color, yield, and quantitative composition of the EO samples studied are strongly influenced by the distillation method. Nonetheless, this C. japonica leaf EO displayed a consistent α-pinene- and sabinene-rich composition. The same chemotype was found in a commercial Azorean C. japonica leaf EO sample, obtained by industrial steam distillation (SD), as well as in Corsica C. japonica leaf EO–HD. Furthermore, the bioactive composition of our EO samples revealed the potential to be used in green plant protection and in the medical, food, cosmetic, and household industries.
- Published
- 2022
- Full Text
- View/download PDF
34. Engineered eco-friendly composite membranes with superhydrophobic/hydrophilic dual-layer for DCMD system.
- Author
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Sayed MM, Noby H, Zkria A, Mousa HM, Yoshitake T, and ElKady M
- Subjects
- Silicon Dioxide chemistry, Hydrophobic and Hydrophilic Interactions, Distillation methods, Water chemistry, Membranes, Artificial, Water Purification methods
- Abstract
Considerable advancements have been made in the development of hydrophobic membranes for membrane distillation (MD). Nonetheless, the environmentally responsible disposal of these membranes poses a critical concern due to their synthetic composition. Herein, an eco-friendly dual-layered biopolymer-based membrane was fabricated for water desalination. The membrane was electrospun from two bio-polymeric layers. The top hydrophobic layer comprises polycaprolactone (PCL) and the bottom hydrophilic layer from cellulose acetate (CA). Additionally, silica nanoparticles (SiO
2 NPs) were electrosprayed onto the top layer of the dual-layered PCL/CA membrane to enhance the hydrophobicity. The desalination performance of the modified PCL-SiO2 /CA membrane was compared with the unmodified PCL/CA membrane using a direct contact membrane distillation (DCMD) unit. Results revealed that silica remarkably improves membrane hydrophobicity. The modified PCL-SiO2 /CA membrane demonstrated a significant increase in water contact angle of 152.4° compared to 119° for the unmodified membrane. In addition, PCL-SiO2 /CA membrane has a smaller average pore size of 0.23 ± 0.16 μm and an exceptional liquid entry pressure of water (LEPw), which is 3.8 times higher than that of PCL/CA membrane. Moreover, PCL-SiO2 /CA membrane achieved a durable permeate flux of 15.6 kg/m2 .h, while PCL/CA membrane showed unstable permeate flux decreasing approximately from 25 to 12 kg/m2 .h over the DCMD test time. Furthermore, the modified PCL-SiO2 /CA membrane achieved a high salt rejection value of 99.97% compared to a low value of 86.2% for the PCL/CA membrane after 24 h continuous DCMD operation. In conclusion, the proposed modified PCL-SiO2 /CA dual-layer biopolymeric-based membrane has considerable potential to be used as an environmentally friendly membrane for the MD process., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)- Published
- 2024
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35. Novel coiled hollow fiber module for high-performance membrane distillation.
- Author
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Almahfoodh S, Qamar A, Kerdi S, and Ghaffour N
- Subjects
- Temperature, Membranes, Artificial, Polyvinyls, Hot Temperature, Distillation methods, Water Purification methods
- Abstract
Membrane distillation (MD) scale-up is challenged by ineffective heat recovery and the temperature polarization effect. Direct contact membrane distillation (DCMD) modules suffer high thermal conduction losses due to feed flow direction along the length of the membrane, resulting in low thermal efficiency. We propose a novel module design named coiled hollow fiber (CHF) to decouple the flow direction from the membrane surface in hollow fiber (HF) DCMD. Experimental and computational analyses were employed to compare the performance of CHF and the conventional design. The CHF module design successfully mitigates the TP effect in HF DCMD, increasing the flux by 148 % and 163 % in cross-flow and localized heating (LH) modes, respectively. Moreover, CHF operated in LH mode exhibits the lowest energy consumption of all configurations (81 % decrease) compared to the conventional design. This novel module design represents a new pathway for efficient and highly performing DCMD module., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
36. Clean-In-Place (CIP) wastewater management using nanofiltration (NF)-forward osmosis (FO)-direct contact membrane distillation (DCMD): Effects of draw salt.
- Author
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Kim WJ, Park HW, and Heldman DR
- Subjects
- Sodium Chloride, Salts, Distillation methods, Calcium Chloride, Ecosystem, Membranes, Artificial, Sodium Chloride, Dietary, Water, Osmosis, Wastewater, Water Purification methods
- Abstract
A substantial amount of water is being used during Clean-in-Place (CIP) operation, and is transformed into wastewater that can cause eutrophication to the nearby ecosystem. The present study proposed the Nanofiltration (NF) - Forward Osmosis (FO) - Direct Contact Membrane Distillation (DCMD) to recover the cleaning agents and reclaim freshwater from the model CIP wastewater. NF steps were suggested as prefiltration steps to remove organic compounds from the CIP wastewater. NF steps reduced the lactose and protein contents by 100 % and 95.6 %, respectively. The permeates from NF steps were further managed by the integrated FO-DCMD system. Several draw salts such as NaCl, KCl, MgCl
2 , and CaCl2 were compared to investigate the influence on FO and DCMD performance. It was found that monovalent salts (NaCl and KCl) outperformed the divalent salts (MgCl2 and CaCl2 ) in terms of water flux for both FO and DCMD. This can be attributed to the lower viscosity and higher mass transfer coefficient. In addition, the replenishment costs of each salt were evaluated since salts loss occurred during FO and DCMD operation. The cost evaluation revealed that NaCl is most the cheapest salts per reclaimed water. All of this observation indicates that NaCl is preferred in terms of water flux and replenishment cost. The NF permeate kept concentrated using the integrated FO-DCMD or single FO with 2 M of NaCl. Compared to a single FO that showed a consistent decline in draw solution concentration, FO-DCMD could maintain the concentration of the draw solution. Despite the constant concentration, flux decline of FO was observed due to fouling formation caused by the high-temperature operation. However, the FO-DCMD could accomplish the recovery of pure water. Finally, the cleaning agents recovered by the NF-FO-DCMD showed the cleaning efficacy comparable to the fresh NaOH. These results suggest the potential of the proposed system to manage the CIP wastewater., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)- Published
- 2024
- Full Text
- View/download PDF
37. Experimental investigation on the hybrid system of mechanical vapor recompression and hollow fiber vacuum membrane distillation applied for wastewater treatment.
- Author
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Si Z, Li Z, Zhuang X, and Zhou D
- Subjects
- Vacuum, Temperature, Hot Temperature, Distillation methods, Water Purification methods
- Abstract
In order to achieve zero discharge and resource utilization of industrial high salt wastewater, a hybrid system of mechanical vapor recompression (MVR) and hollow fiber vacuum membrane distillation (HFVMD) was constructed, and several experiments of air tightness, single working condition and multiple working conditions were carried out with ammonium chloride solution as feed, then thermal economic performance were evaluated via a single factor analysis method. The obtained results showed that the system had excellent airtightness to ensure normal evaporation experiment, and high separation efficiency of 99.9% and lower evaporation energy consumption to achieve high efficient separation by combining the advantages of the hydrophobic membrane evaporation and latent heat recovery in view of MVR and HFVMD technologies. Furthermore, increasing feed temperature and feed flow rate increased evaporation rate and decreased evaporation energy consumption, while increasing feed concentration decreased evaporation rate and increased evaporation energy consumption. Finally, the single factor analysis indicated that total investment cost, annual operation cost and annual evaporation capacity were the main factors while environmental cost and equipment service life were the secondary factors which affected the specific evaporation cost. The above research provides theoretical and experimental bases for the development of the proposed system in the future., Competing Interests: Declaration of competing interest No conflict of interest exits in the submission of this paper, and paper is approved by all authors listed for publication. The authors claim that none of the material in the paper has been published or is under consideration for publication elsewhere., (Copyright © 2023 Elsevier Ltd. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
38. Preparation of High-Purity Docosahexaenoic Acid Ethyl Ester from Algal Oil through Enzymatic Ethanolysis.
- Author
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Li J, Lin S, Liu X, Chen W, Lan D, and Wang Y
- Subjects
- Microalgae chemistry, Fish Oils chemistry, Distillation methods, Esterification, Biocatalysis, Docosahexaenoic Acids isolation & purification, Docosahexaenoic Acids chemistry, Lipase metabolism, Lipase chemistry, Esters chemistry, Ethanol chemistry
- Abstract
Docosahexaenoic acid plays a crucial role in infant brain function, and the market demand of high-purity docosahexaenoic acid is continuously increasing. The availability of docosahexaenoic acid in natural fish oil is limited, prompting the exploration of alternative sources like microalgae. For algal oil, enzymatic ethanolysis is preferred to chemical methods because the former is milder and can avoid docosahexaenoic acid oxidation. However, enzymatic methods have generally low yield due to the poor substrate-specificity of lipase to long-chain polyunsaturated fatty acids, affecting the yield and purity of docosahexaenoic acid. Therefore, we developed an efficient process to produce high-purity docosahexaenoic acid ethyl ester from algal oil, by screening lipases, optimizing enzymatic ethanolysis and applying molecular distillation. Lipase UM1 was the best lipase to produce ethyl ester from algal oil with the highest ethyl ester yield (95.41%). Meanwhile, it was a catalyst for the reaction of long-chain polyunsaturated fatty acids with ethanol. The fatty acid docosahexaenoic acid conversion rates exceeded 90%. After molecular distillation, a final product containing 96.52% ethyl ester was obtained with a docosahexaenoic acid content up to 80.11%. Our findings provide an highly effective enzymatic method for the production of high-purity docosahexaenoic acid ethyl esters, with potential commercial applications.
- Published
- 2024
- Full Text
- View/download PDF
39. Review of the valorization initiatives of brewing and distilling by-products.
- Author
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Umego EC and Barry-Ryan C
- Subjects
- Fermentation, Distillation methods, Alcoholic Beverages, Food Handling methods, Functional Food, Edible Grain chemistry, Humans, Beer
- Abstract
Beer and spirits are two of the most consumed alcoholic beverages in the world, and their production generates enormous amounts of by-product materials. This ranges from spent grain, spent yeast, spent kieselguhr, trub, carbon dioxide, pot ale, and distilled gin spent botanicals. The present circular economy dynamics and increased awareness on resource use for enhanced sustainable production practices have driven changes and innovations in the management practices and utilization of these by-products. These include food product development, functional food applications, biotechnological applications, and bioactive compounds extraction. As a result, the brewing and distilling sector of the food and drinks industry is beginning to see a shift from conventional uses of by-products such as animal feed to more innovative applications. This review paper therefore explored some of these valorization initiatives and the current state of the art.
- Published
- 2024
- Full Text
- View/download PDF
40. Separation techniques for manufacturing fruit spirits: From traditional distillation to advanced pervaporation process.
- Author
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Wang X, Cui W, Guo W, Sun B, Huang M, Li J, Li H, and Meng N
- Subjects
- Fruit chemistry, Distillation methods
- Abstract
Separation process is one of the key processes in the production of fruit spirits, including the traditional distillation method and the new pervaporation membrane method. The separation process significantly determines the constituents and proportions of compounds in the fruit spirit, which has a significant impact on the spirit quality and consumer acceptance. Therefore, it is important and complex to reveal the changing rules of chemical substances and the principles behind them during the separation process of fruit spirits. This review summarized the traditional separation methods commonly used in fruit spirits, covering the types, principles, and corresponding equipment of distillation methods, focused on the enrichment or removal of aroma compounds and harmful factors in fruit spirits by distillation methods, and tried to explain the mechanism behind it. It also proposed a new separation technology for the production of fruit spirits, pervaporation membrane technology, summarized its working principle, operation, working parameters, and application in the production of fruit spirits, and outlined the impact of the separation method on the production of fruit spirits based on existing research, focusing on the separation of flavor compounds, sensory qualities, and hazard factors in fruit spirits, along with a preliminary comparison with distillation. Finally, according to the current researches of the separation methods and the development requirement of the separation process of fruit spirits, the prospect of corresponding research is put forward, in order to propose new ideas and development directions for the research in this field., (© 2023 Institute of Food Technologists®.)
- Published
- 2024
- Full Text
- View/download PDF
41. Theoretical and experimental investigation of cylindrical air gap membrane distillation system and effect of the membrane support net on its performance.
- Author
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Shahu VT and Thombre SB
- Subjects
- Membranes, Artificial, Temperature, Hot Temperature, Distillation methods, Water Purification methods
- Abstract
In present study a cylindrical module is studied based on air gap membrane distillation configuration and studied for desalination purpose. A complete theoretical model was developed with consideration of design and operating parameters that enabled a Cylindrical Air Gap Membrane Distillation (CAGMD) module specific performance analysis. Theoretical model was verified with the literature as well as with the experimental results carried out on a lab scale CAGMD module. The effect of support nets which supports the membrane on the air gap side is also discussed on the performance. Support nets made up of four different thermal conductivities material- copper, aluminum, brass and polypropylene (PP) are considered for this study. The effect of feed temperature and flow rate, air gap width, cold flow rate, effect of thermal conductivities of support nets and height of the module was studied on the performance of CAGMD module. Permeate flux, Specific Thermal Energy Consumption (STEC) and the Gained output ratio (GOR) was selected as the performance indicators and the results for all the resulted parameters obtained from experimental and theoretical model falls in good agreement with only 6% deviation, that suggests that the proposed model is best suitable for predicting the behavior of any cylindrical AGMD module with great effectiveness. It is suggested that for better performance of the system feed flow rate, temperature and cold flow rate should be maintained at higher level. Maximum permeate flux achieved from the CAGMD module is 9.22 kg/m
2 h., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)- Published
- 2024
- Full Text
- View/download PDF
42. Cross-modal interactions caused by nonvolatile compounds derived from fermentation, distillation and aging to harmonize flavor.
- Author
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Jia W and Ma R
- Subjects
- Humans, Volatile Organic Compounds analysis, Odorants analysis, China, Food Handling methods, Chromatography, High Pressure Liquid methods, Fermentation, Taste, Distillation methods, Flavoring Agents chemistry, Flavoring Agents analysis, Gas Chromatography-Mass Spectrometry methods, Alcoholic Beverages analysis
- Abstract
Chinese liquor (Baijiu), unique liquor produced in China and among the six world-renowned distilled liquors, is never a follower of others. Flavor is the essential characteristics of Baijiu which largely affect consumers' acceptance and selection. Though the flavor of Baijiu has been widely explored, the majority of research and review mainly focused on the volatile compounds in Baijiu. The research status on detection, source and flavor contribution of nonvolatile compounds in Baijiu is clarified in the article based on available literatures and knowledge. The nonvolatile composition of Baijiu is the result of contributions of different degrees from each step involved in the production process. Gas chromatography-mass spectrometry combined with derivatization and ultra-high performance liquid chromatography coupled to mass spectrometry is the generally adopted methods for the characterization of nonvolatile compounds in Baijiu. Certain nonvolatile compounds are taste-active compounds. Cross-modal interactions caused by nonvolatile composition could affect the aroma intensity of flavor compounds in Baijiu. The work provides numerous incompletely explored but useful points for the flavor chemistry of Baijiu and lays a theoretical foundation for the better understanding of Baijiu flavor and rapid development of Baijiu industry.
- Published
- 2024
- Full Text
- View/download PDF
43. Assessment of Japanese Awamori Spirits Using UV–VIS Spectroscopy.
- Author
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Li, Xinyue, Tsuta, Mizuki, Tanaka, Fukuyo, Tsukahara, Masatoshi, and Tsukahara, Keiko
- Abstract
Awamori is a traditional distilled alcohol beverage unique to Okinawa, Japan. This study evaluated the potential of ultraviolet–visible (UV–VIS) spectroscopy in the assessment and differentiation of different Awamori samples. Thirty-one Awamori samples that could be classified differently based on attributes such as their distillation methods (atmospheric distillation and vacuum distillation), aging periods (0–18 years), batches (years 2017 and 2014), and distilleries of origin were investigated by UV–VIS spectroscopy and chromatographic analysis. Principal component analysis (PCA) of UV–VIS spectra showed that Awamori of atmospheric distillation and vacuum distillation could be clearly distinguished based on low and high PC1 scores, respectively; both young Awamori (aged less than 3 years) and Awamori from the 2017 batch exhibited low PC1 scores and high PC2 scores. Wavelength ranges with high loading values that correspond to the volatile compounds which have high correlations with PC scores, such as furfural, phenethyl alcohol, vanillin, and benzaldehyde, were observed in the UV–VIS spectral profiles. These volatile compounds with unique aroma characteristics can characterize Awamori attributes. Therefore, UV–VIS spectroscopy with the aid of chemometric analysis was demonstrated as a high potential technique for the rapid and low-cost evaluation and characterization of Awamori samples. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
44. Modification of the distribution of humic acid complexations by introducing microbubbles to membrane distillation process for effective membrane fouling alleviation.
- Author
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Wang X, Li P, Ye Y, Xu C, Liu Y, Li E, Xia Q, Hou L, and Yu S
- Subjects
- Distillation methods, Microbubbles, Membranes, Artificial, Cations, Humic Substances analysis, Water Purification methods
- Abstract
Membrane fouling caused by inorganic ions and natural organic matters (NOMs) has been a severe issue in membrane distillation. Microbubble aeration (MB) is a promising technology to control membrane fouling. In this study, MB aeration was introduced to alleviate humic acid (HA) composited fouling during the treatment of simulative reverse osmosis concentrate (ROC) by vacuum membrane distillation (VMD). The objective of this work was to explore the HA fouling inhibiting effect by MB aeration and discuss its mechanism from the interfacial point of view. The results showed that VMD was effective for treating ROC, followed by a severe membrane fouling aggravated with the addition of 100 mg/L HA in feed solution, resulting in 45.7% decline of membrane flux. Analysis using the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory and zeta potential distribution of charged particles proved the coexistence of HA and inorganic cations (especially Ca
2+ ), resulting in more serious membrane fouling. The introduction of MB aeration exhibited excellent alleviating effect on HA-inorganic salt fouling, with the normalized flux increased from 19.7% to 37.0%. The interfacial properties of MBs played an important role, which altered the zeta potential distributions of charged particles in HA solution, indicating that MBs adhere the HA complexations. Furthermore, this mitigating effect was limited at high inorganic cations concentration. Overall, MBs could change the potential characteristics of HA complexes, which also be used for other similar membrane fouling alleviation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)- Published
- 2023
- Full Text
- View/download PDF
45. Water and salt recovery from shale gas produced water by vacuum membrane distillation followed by crystallization.
- Author
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Qiu B, Liu J, Liu Y, Wang Y, Xiao Z, and Fan S
- Subjects
- Vacuum, Salts chemistry, Natural Gas, Distillation methods, Crystallization, Membranes, Artificial, Sodium Chloride, Water chemistry, Water Purification methods
- Abstract
A vacuum membrane distillation (VMD) followed by crystallization (VMD-C) was developed for the recovery of water and salts from shale gas produced water (SGPW). Before VMD, the pretreatment of SGPW with Fenton oxidation-flocculation is applied, with the chemical oxygen demand (COD) concentration reduction of 75% and the total removal of the total suspended solids (TSS), Ca
2+ , and Mg2+ in SGPW. The pretreatment of SGPW mitigated the membrane fouling in the VMD and effectively prevented the reduction of membrane flux over time. The average flux of the PTFE membrane reached 12.1 kg m-2 h-1 during the separation of the pretreated SGPW at a feed flux of 40 L h-1 and a feed temperature of 40 °C. The rejection rate of the membrane to TDS in SGPW was over 99%. Fresh water with a conductivity of below 20 μs cm-1 was produced by VMD-C. The salts concentrated upstream of the membrane were recovered by a stirring crystallization process. The VMD-C system resulted in a 61% cost savings compared to conventional SGPW treatment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)- Published
- 2023
- Full Text
- View/download PDF
46. Mineral scaling induced membrane wetting in membrane distillation for water treatment: Fundamental mechanism and mitigation strategies.
- Author
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Chang H, Zhu Y, Huang L, Yan Z, Qu F, and Liang H
- Subjects
- Distillation methods, Membranes, Artificial, Wettability, Minerals, Water Purification methods
- Abstract
The scaling-induced wetting phenomenon seriously affects the application of membrane distillation (MD) technology in hypersaline wastewater treatment. Unlike the large amount of researches on membrane scaling and membrane wetting, scaling-induced wetting is not sufficiently studied. In this work, the current research evolvement of scaling-induced wetting in MD was systematically summarized. Firstly, the theories involving scaling-induced wetting were discussed, including evaluation of scaling potential of specific solutions, classical and non-classical crystal nucleation and growth theories, observation and evolution of scaling-induced processes. Secondly, the primary pretreatment methods for alleviating scaling-induced wetting were discussed in detail, focusing on adding agents composed of coagulation, precipitation, oxidation, adsorption and scale inhibitors, filtration including granular filtration, membrane filtration and mesh filtration and application of external fields including sound, light, heat, electromagnetism, magnetism and aeration. Then, the roles of operation conditions and cleaning conditions in alleviating scaling-induced wetting were evaluated. The main operation parameters included temperature, flow rate, pressure, ultrasound, vibration and aeration, while different types of cleaning reagents, cleaning frequency and a series of assisted cleaning measures were summarized. Finally, the challenges and future needs in the application of nucleation theory to scaling-induced wetting, the speculation, monitoring and mitigation of scaling-induced wetting were proposed., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)
- Published
- 2023
- Full Text
- View/download PDF
47. Nanocomposite Hydrogel Engineered Janus Membrane for Membrane Distillation with Robust Fouling, Wetting, and Scaling Resistance.
- Author
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Yang X, Zhang N, Zhang J, Liu W, Zhao M, Lin S, and Wang Z
- Subjects
- Nanogels, Distillation methods, Membranes, Artificial, Hydrogels, Polytetrafluoroethylene, Surface-Active Agents, Wastewater, Water Purification methods
- Abstract
Membrane distillation (MD) is considered to be rather promising for high-salinity wastewater reclamation. However, its practical viability is seriously challenged by membrane wetting, fouling, and scaling issues arising from the complex components of hypersaline wastewater. It remains extremely difficult to overcome all three challenges at the same time. Herein, a nanocomposite hydrogel engineered Janus membrane has been facilely constructed for desired wetting/fouling/scaling-free properties, where a cellulose nanocrystal (CNC) composite hydrogel layer is formed in situ atop a microporous hydrophobic polytetrafluoroethylene (PTFE) substrate intermediated by an adhesive layer. By the synergies of the elevated membrane liquid entry pressure, inhibited surfactant diffusion, and highly hydratable surface imparted by the hydrogel/CNC (HC) layer, the resultant HC-PTFE membrane exhibits robust resistance to surfactant-induced wetting and oil fouling during 120 h of MD operation. Meanwhile, owing to the dense and hydroxyl-abundant surface, it is capable of mitigating gypsum scaling and scaling-induced wetting, resulting in a high normalized flux and low distillate conductivity at a concentration factor of 5.2. Importantly, the HC-PTFE membrane enables direct desalination of real hypersaline wastewater containing broad-spectrum foulants with stable vapor flux and robust salt rejection (99.90%) during long-term operation, demonstrating its great potential for wastewater management in industrial scenarios.
- Published
- 2023
- Full Text
- View/download PDF
48. Qualitative and Quantitative Comparison of Aromatic Oil Components and Antifungal Effects of Cymbopogon flexuosus Obtained with Supercritical CO 2 , Microwave-Ultrasonic, Steam Distillation, and Hydrodistillation Extraction Techniques.
- Author
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Jaradat N
- Subjects
- Distillation methods, Antifungal Agents pharmacology, Antifungal Agents analysis, Steam, Carbon Dioxide, Microwaves, Fluconazole, Ultrasonics, Gas Chromatography-Mass Spectrometry, Oils, Volatile chemistry, Cymbopogon
- Abstract
Cymbopogon flexuosus is a highly valued botanical species with significant applications in the food and food supplement industries, medicine, and cosmetics. The effects of four extraction techniques, supercritical CO
2 , microwave-ultrasonic, steam distillation, and hydrodistillation techniques, on the yield, phytochemical constituents, and antifungal activity against nine fungal species of Cymbopogon flexuosus aromatic oil (AO) were explored in this investigation. Gas chromatography connected with a mass spectrometry apparatus was employed for the qualitative and quantitative analyses of the investigated plant AOs. In addition, using the broth microdilution method, minimum inhibitory concentrations (MICs) were calculated for several fungi species. The supercritical CO2 method gave the highest yield of AO (11.62 ± 0.03 ( w / w )) followed by the microwave-ultrasonic method (1.55 ± 0.05% ( w / w )) and the steam distillation method (1.24 ± 0.04% ( w / w )), while the hydrodistillation methods gave the lowest yield (1.17 ± 0.01 ( w / w )). In addition, eighteen molecules were specified in the AOs obtained with the supercritical CO2 , microwave-ultrasonic, steam distillation, and hydrodistillation techniques, which constituted 99.36, 98.6, 98.21, and 98.31% ( v / v ) of the total oils, respectively. Additionally, linalyl acetate was the trending molecule in the microwave-ultrasonic and steam distillation methods, representing 24.61 and 24.34% ( v / v ), respectively, while geranial was the dominant molecule in the AOs extracted with the hydrodistillation and supercritical CO2 extraction techniques (27.01 and 25.6% ( v / v ), respectively). The antifungal screening results revealed that the tested C. flexuosus AOs have potential antifungal effects against all the screened fungi species. The antifungal effect of the AOs extracted with the steam distillation and microwave-ultrasonic methods was remarkable compared with that of the commercial antifungal drug Fluconazole. However, the AOs extracted with these two methods have a more potent antifungal effect against Candida parapsilosis than that of Fluconazole with MICs of 3.13 ± 0.01, 3.13 ± 0.01, and 6.25 ± 0.91 µg/mL, respectively. The same effects were also observed against Trichophyton rubrum with MICs of 6.25 ± 0.91 µg/mL, respectively. The results of this investigation demonstrated that the steam distillation and microwave-ultrasonic methods are promising processes for the extraction of C. flexuosus AO with a potent antifungal effect. This may be an advantage for the utilization of C. flexuosus AO over some antifungal synthetic agents commonly utilized as medicines, preservatives, food additives, cosmetics, and nutrient supplements.- Published
- 2023
- Full Text
- View/download PDF
49. Treatment of high-salinity brine containing dissolved organic matters by vacuum membrane distillation: A fouling mitigation approach via microbubble aeration.
- Author
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Zhang W, Yu S, Ning R, Li P, Ji X, and Xu Y
- Subjects
- Dissolved Organic Matter, Distillation methods, Vacuum, Salinity, Membranes, Artificial, Microbubbles, Water Purification methods
- Abstract
In this study, a laboratory-scale vacuum membrane distillation (VMD) system coupled with microbubble aeration (MBA) was developed for the treatment of high-salinity brine containing organic matters. Herein, at the beginning, feedwater only containing model organics such as humic acid (HA), bovine serum albumin (BSA) and sodium alginate (SA) was utilized to investigate the organic-fouling behavior, results indicated that the permeate flux was not affected by a thin and loose contaminated layer deposited on the membrane surface. Furthermore, dissolved organics in the feed brine inhibited the occurrence of membrane wetting due to the existence of a compact and protective crystals/organic-fouling layer, which can prevent the intrusion of scaling ions into membrane substrates. Besides, organics in the feedwater have a high tendency to adsorb on the membrane surface based on molecular dynamics simulations, thus, forming an organic-fouling layer prior to inorganic scaling. Finally, the effect of MBA on fouling alleviation was evaluated in VMD system, nearly 50% of salt precipitation from fouled membrane was effectively removed with the introduction of MBA, which can be ascribed to a combination of mechanisms, including surface shear forces and electrostatic attractions induced by microbubbles, meanwhile, about 2.2% of the total energy was only consumed, when using MBA. Together, these results demonstrated that MBA was a promising approach to alleviate membrane fouling in VMD., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)
- Published
- 2023
- Full Text
- View/download PDF
50. Virus rejection and removal in pilot-scale air-gap membrane distillation.
- Author
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Hardikar M, Felix V, Rabe AB, Ikner LA, Hickenbottom KL, and Achilli A
- Subjects
- Distillation methods, Osmosis, Membranes, Artificial, Water, Wastewater, Water Purification methods
- Abstract
Membrane distillation (MD) is a thermally-driven process that can treat high concentration streams and provide a dual barrier for rejection and reduction of pathogens. Thus, MD has potential applications in treating concentrated wastewater brines for enhancing water recovery and potable water reuse. In bench-scale studies, it was demonstrated that MD can provide high rejection of MS2 and PhiX174 bacteriophage viruses, and when operating at temperatures greater than 55 °C, can reduce virus levels in the concentrate. However, bench-scale MD results cannot directly be used to predict pilot-scale contaminant rejection and removal of viruses because of the lower water flux and higher transmembrane hydraulic pressure difference in pilot-scale systems. Thus far, virus rejection and removal have not been quantified in pilot-scale MD systems. In this work, the rejection of MS2 and PhiX174 at low (40 °C) and high (70 °C) inlet temperatures is quantified in a pilot-scale air-gap MD system using tertiary treated wastewater. Both viruses were detected in the distillate which suggests the presence of pore flow; the virus rejection at a hot inlet temperature of 40 °C for MS2 and PhiX174 were 1.6-log
10 and 3.1-log10 , respectively. At 70 °C, virus concentrations in the brine decreased and were below the detection limit (1 PFU per 100 mL) after 4.5 h, however, viruses were also detected in the distillate in that duration. Results demonstrate that virus rejection is lower in pilot-scale experiments because of increased pore flow that is not captured in bench-scale experiments., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)- Published
- 2023
- Full Text
- View/download PDF
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