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Methanol is expected to be a possible solution for reducing global greenhouse gas emissions and minimizing the dependency on fossil fuels. This paper presents a systematic approach of methanol (MeOH) production from industrial waste gases including flue gas (FG) and coke oven gas (COG) that are considered an important threat to the environment. The impact of process parameters, including dimensional parameters (length, diameter, and number of tubes) and operational parameters (reactor temperature, pressure, and thermal fluid temperature) over the MeOH synthesis, are investigated by Aspen Plus. Firstly, the synthesis process is designed and optimized using syngas (SG) as a feed material. Secondly, by replacing the feed material with FG and COG, methanol production variability is investigated and demonstrated for the same optimized process. Afterward, an efficient heat exchange network system is developed for all three different processes using Aspen Energy Analyzer. The optimized dimensional parameters of the MeOH synthesis reactor are determined to be a length of 12 m, a diameter of 0.06 m, and 5000 tubes for achieving a conversion rate of 75%. Meanwhile, the optimized operational parameters are identified as a reactor temperature of 209   ° C , reactor pressure of 70 bar, and thermal fluid temperature of 196   ° C . Furthermore, the influence of the stoichiometric number (SN) on the process was observed with higher SN values resulting in increased hydrogen (H2) concentration and an improved forward reaction of MeOH synthesis, leading to higher conversion rates. The findings and insights gained from this study can serve further improvements and advancements in MeOH synthesis processes. [ABSTRACT FROM AUTHOR]

Protonic ceramic electrochemical cells (PCECs) are promising energy storage technologies due to their high performance and ability to convert CO2 into value-added chemicals. However, there are many fundamental aspects of this technology that require investigation to better understand its interactions and opportunities. Thus, this paper focuses on the development of a steady-state PCEC model, encompassing intricate details of reactive porous-media transport, elementary catalytic chemistry, and electrochemistry within unit cells. The model is calibrated and validated using experimental data. The model presents the rate of methane production at different temperatures and revealed that efficient PCEC for co-electrolysis of CO 2 and H 2 O is operated in the temperature range of 420–470 °C and the optimum being 450 °C at the rate of 0.0391 moldm−3 min−1. It provides insights into the effects of overpotentials on cell performance. At a current density of 3000 A/m2 the ohmic, concentration, and activation overpotentials amount to 0.65, 0.004, and 0.19 V, respectively. The results obtained from the model highlight the potential of PCECs as efficient CO 2 sinks for decarbonization purposes and as a means of methane production. Furthermore, the model's findings offer valuable guidance for the design, selection of stacks, and choice of building materials in PCEC systems. The potential applications of PCECs as real-life fuel utilization technologies are justified with improved material development to reduce cell overpotentials, opening doors for scale-up and eventual commercialization. These findings contribute to the development of sustainable energy systems and advance the pursuit of decarbonization goals. • A protonic ceramic electrolysis cell (PCEC) model for co-electrolysis of CO 2 and H 2 O is developed. • Model calibration and validation are performed for the PCEC • The PCEC is best operated in the temperature range of 400–500 °C for Sabatier reaction. • The optimum temperature for methane production is 450 °C at the rate of 0.0391 moldm−3 min−1. • The effects gas composition and temperature on cell performance are investigated. [ABSTRACT FROM AUTHOR]

Magnetic chitosan nanoparticles, synthesized by in situ precipitation, have been used as adsorbents to remove sulfamethoxazole (SMX), a sulfonamide antibiotic dangerous due to its capacity to enter ecosystems. The adsorption of SMX has been carried out in the presence of tertiary wastewaters from a depuration plant to obtain more realistic results. The effect of pH on the adsorption capacity significantly changed when carrying out the experiments in the presence of wastewater. This change has been explained while taking into account the charge properties of both the antibiotic and the magnetic chitosan. The composition of wastewaters has been characterized and discussed as regards its effect on the adsorption capacity of the magnetic chitosan. The models of Elovich and Freundlich have been selected to describe the adsorption kinetics and the adsorption isotherms, respectively. The analysis of these models has suggested that the adsorption mechanism is based on strong chemical interactions between the SMX and the magnetic chitosan, leading to the formation of an SMX multilayer. [ABSTRACT FROM AUTHOR]

This study was conducted to evaluate the effectiveness of a simplified, low cost, pasteurization device in inactivating the diarrheal pathogens present in pond/lake/river water in order to provide safe potable water to people living in the rural areas of low resource countries. In this process, water in polyethylene bags was exposed to sunshine, where UV radiation emissions and heat absorption from the sunshine occurs simultaneously, and maintaining the heating at <60 C, and minimum UV radiation emissions of 996.2 W/m2 for approximately 30 minutes was found enough to inactivate diarrheal pathogens in water. The synergistic effect of heat, UV radiation emission and holding time causes the destruction of diarrheal pathogens. However, the performance of the device depends on the thickness of the insulation and the air gap between polyethylene bags. Regardless of sample sources, the highest population reduction of Escherichia coli observed in the bacterial challenge study was 6.8±0.4 log CFU/ml. The physicochemical properties were found acceptable compared with USEPA potable water quality except turbidity, which is acceptable according to the BDS standard, and the shelf-life study results demonstrated that 6 months' storage of pasteurization device-treated water at room temperature is possible without compromising water quality. Therefore, this simplified pasteurization device could be useful in potable water-scarce areas of the world. [ABSTRACT FROM AUTHOR]

The discharge of palm oil mill effluent (POME) on arable land causes large amounts of environmental distress due to its high concentration of phenolic compounds and chemical oxygen demand (COD). The approach of simultaneous microbial oil production and wastewater treatment is an attractive option to combine renewable energy production and environmental resilience. This study aims to produce cost effective microbial lipids using the oleaginous yeast Lipomyces starkeyi through the bioremediation of POME. A moderately dilute solution (50%) of POME showed higher microbial growth and lipid accumulation and offered a significantly higher degree of bioremediation. A lipid content of 21.32% was achieved with 50% POME, whereas the value was 15.14% for 25% POME. Three different techniques including ultrasonic treatment, Fenton's reagent and Fenton's + ultrasonic were employed to extract lipids from microbial biomass, and the maximum lipid concentration was obtained using the Fenton's + ultrasonic treatment. The degree of bioremediation was evaluated by the calculating seed germination index (GI) values. Higher GI values were observed for the 25% and 50% dilutions compared to undiluted (100%) POME. This combined approach can be a potential alternative technology that integrates bioremediation of POME with microbial lipid production. [ABSTRACT FROM AUTHOR]

Biogas is a type of renewable energy which provides clean energy, reduces environmental pollution and greenhouse gas caused by the biological wastes, creates job opportunity for skilled and unskilled persons, and offers new income sources for investors. However, mostly practiced small-scale or family-size biogas plant becomes unsuccessful due to the lack of financial attractiveness. Therefore, it is essential to design a proper financial mode of operation to sustain this technology. The policy makers, investors, and researchers should develop a viable financial mechanism to attract the investors by offering loan with flexible conditions, restructure the subsidies skim, and liberalize the gas grid management and involvement of the end users in biogas project. The engagement of social business concept can stimulate the sustainability of the biogas technology and make it financially gorgeous. This study proposed a number of social business plans and described microeconomic evaluation systems to calculate their commercial viability to improve the survival of biogas technology. [ABSTRACT FROM PUBLISHER]

Biogas technology, which converts biological waste into energy, is considered as an excellent tool to improve the lives, livelihoods, health, and ecosystem. The demand and prospect of biogas technology as a renewable energy source in terms of market value have not been adequately addressed, although it offers a large revenue opportunity that supports the socioeconomic development in rural areas. For more sustainable development of this technology, policy-makers should reform the existing institutional framework by reorganizing subsidies, motivating and attracting investors with flexible financial conditions, liberalizing the management of gas grids, and involving farmers in local projects. Therefore, it is a great challenge to find a proper mode of marketing policy, business models, and multi-profit options and a sustainable financing mechanism. This paper covers the state-of-the-art enlargements and future consequences of the hastily emerging biogas market, starting with a universal viewpoint and going through special market characteristics of Europe, USA, Africa, and Asia Pacific. [ABSTRACT FROM AUTHOR]

Abstract: Biodiesel can be a potential alternative to petroleum diesel, but its high production cost has impeded its commercialization in most parts of the world. One of the main drivers for the generation and use of biodiesel is energy security, because this fuel can be produced from locally available resources, thereby reducing the dependence on imported oil. Many countries are now trying to produce biodiesel from plant or vegetable oils. However, the consumption of large amounts of vegetable oils for biodiesel production could result in a shortage in edible oils and cause food prices to soar. Alternatively, the use of animal fat, used frying oils, and waste oils from restaurants as feedstock could be a good strategy to reduce the cost. However, these limited resources might not meet the increasing demand for clean, renewable fuels. Therefore, recent research has been focused the use of residual materials as renewable feedstock in order to lower the cost of producing biodiesel. Microbial oils or single cell oils (SCOs), produced by oleaginous microorganisms have been studied as promising alternatives to vegetable or seed oils. Various types of agro-industrial residues have been suggested as prospective nutritional sources for microbial cultures. Since the most abundant residue from agricultural crops is lignocellulosic biomass (LCB), this byproduct has been given top-priority consideration as a source of biomass for producing biodiesel. But the biological transformation of lignocellulosic materials is complicated due to their crystalline structure. So, pretreatment is required before they can be converted into fermentable sugar. This article compares and scrutinizes the extent to which various microbes can accumulate high levels of lipids as functions of the starting materials and the fermentation conditions. Also, the obstacles associated with the use of LCB are described, along with a potentially viable approach for overcoming the obstacles that currently preclude the commercial production of biodiesel from agricultural biomass. [Copyright &y& Elsevier]

Solid oxide electrolysis cells (SOECs) proffer a flexible and environmentally friendly solution to reduce CO 2 emissions and/or produce H 2 fuel for various applications. The integration of this technology with renewable energy systems makes them even more promising in realizing a near-perpetual green energy infrastructure in the near future. SOEC technology has achieved stupendous improvement in recent years, and some of the limiting factors to the commercialization of this technology have been explored. It is, therefore, necessary to have a succinct outlook of the different factors that contribute to the recent developments in SOEC technology. The current work presents a comprehensive review of the state-of-the-art SOEC component materials and their degradation mechanisms, SOEC modeling essentials and efficiencies, and the scalability of SOECs. Although SOEC is considered a highly promising technology and sufficient multifaceted research has been done, yet not been widely commercialized. Despite the improvement to mitigate degradation of the SOEC materials, a large share of the degradation concerns sprang from charge transfer reaction at the triple-phase boundaries of the H 2 -electrode. Part of which can be improved by microkinetic modeling of these materials supported by their characterization to give insight into their development. Some other directions for the future in advancing this technology toward the commercialization stage are thoroughly addressed. • It reviews the state-of-the-art SOEC component materials and their degradation mechanisms. • The distribution of gas flow affects the electrochemistry of an SOEC stack. • Stack and system-level models should be comprehensive, flexible, and less complex. • Accurate evaluation for stake and system level will greatly boost its commercialization. [ABSTRACT FROM AUTHOR]

Bioethanol is an eco-friendly biofuel due to its merit that makes it a top-tier fuel. The present study emphasized on bioethanol production from hydrogen-rich syngas through fermentation using Sacharomyces cerevisiea. Syngas fermentation was performed in a tar free fermenter using a syngas mixture of 13.05% H 2 , 22.92% CO, 7.9% CO 2 , and 1.13% CH 4 , by volume. In the fermentation process, effects of various parameters including syngas impurity, temperature, pH, colony forming unit, total organic carbon and syngas composition were investigated. The yield of bioethanol was identified by Gas chromatography-Mass spectrometry analysis and further, it was confirmed by Nuclear magnetic resonance (1H) analysis. From GC-MS results, it is revealed that the concentration of bioethanol using Saccharomyces cerevisiae was 30.56 mmol from 1 L of syngas. Thus, hydrogen-rich syngas is suited for bioethanol production through syngas fermentation using Saccharomyces cerevisiae. This research may contribute to affordable and environment-friendly bioethanol-based energy to decrease the dependency on fossil fuels. Image 1 • Hydrogen-rich syngas was converted into bioethanol using a tar free fermenter (TFF) • Saccharomyces cerevisiae was suited microorganism for syngas fermentation • Produced bioethanol was detected using (1H) NMR and GC-MS analysis [ABSTRACT FROM AUTHOR]

Highlights • Economically feasible production routes simulation for ethanol and furfural. • Non heat integrated biochemical routes annual profitability is $3.28 million. • Non heat integrated thermochemical routes annual profitability is $1.10 million. • Heat integration increases profitability and lowers ethanol production cost. • Heat integrated biochemical route produces per gallon ethanol at $2.0. Abstract In a quest of alternative energy source of fossil fuels, lignocellulosic biomass is intensively studying to produce different liquid fuels and chemicals. Both fuel (bioethanol) and chemical (furfural) were produced simultaneously in this study through two different production routes, biochemical and thermochemical route. Actually, this study firstly defined production pathway in details for each production route from extensive literature survey. Later details production pathway simulation was carried out in Aspen Plus simulation software for each production route individually. As well as heat integration was carried out within each production route to make overall production process as energy efficient and more profitable. Finally, an economic analysis of each production route ensured economic feasibility as well as annual profitability for bioethanol and furfural coproduction in individual route. Moreover, a comparative study between production routes in terms of annual profitability showed that heat integrated biochemical route is more profitable for bioethanol and furfural coproduction. Based on processing of 658201.14 ton dry lignocellulosic biomass (corn stover) per year, heat integrated biochemical production route can produce per gallon bioethanol by $2.0 and can make $49.95 million annual profit, whereas, the values were $3.07 and $20.07 respectively for heat integrated thermochemical route. [ABSTRACT FROM AUTHOR]

A long-term (1948 to 2012) trend of precipitation (annual, pre-monsoon, monsoon, and post-monsoon seasons) in Bangladesh was analyzed in different regions using both parametric and nonparametric approaches. Moreover, the possible teleconnections of precipitation (annual and monsoon) variability with El Niño/Southern Oscillation (ENSO) episode and Indian Ocean Dipole (IOD) were investigated using both average and individual (both positive and negative) values of ENSO index and IOD. Our findings suggested that for annual precipitation, a significant increasing monotonic trend was found in whole Bangladesh (4.87 mm/year), its western region (5.82 mm/year) including Rangpur (9.41 mm/year) and Khulna (4.95 mm/year), and Sylhet (10.12 mm/year) and Barisal (6.94 mm/year) from eastern region. In pre-monsoon, only Rangpur (2.88 mm/year) showed significant increasing trend, while in monsoon, whole Bangladesh (3.04 mm/year), Sylhet (7.17 mm/year), and Barisal (6.94 mm/year) showed similar trend. In post-monsoon, there was no significant trend. Our results also revealed that the precipitation (annual or monsoon) of whole Bangladesh and almost all of the spatial regions did not show any significant correlation with ENSO events, whereas the average IOD values showed significant correlation only in monsoon precipitation of western region. The individual positive IODs showed significant correlation in whole Bangladesh, western region, and its two divisions (Rajshahi and Khulna). So, in the context of Bangladesh climate, IOD has the more teleconnection to precipitation than that of ENSO. Our findings indicate that the co-occurrence of ENSO and IOD events may suppress their influence on each other. [ABSTRACT FROM AUTHOR]

The purpose of this research is to evaluate the intent of empty fruit bunches of palm oil (EFBpalm oil) to catalytic gasification of wood produced charcoal (Woodcharcoal) in order to notify the large-scale application of Woodcharcoal as a possible gasification feedstock. In this study, co-catalyst of bismuth oxide (Bi2O3) was also used to obtain syngas. The raw samples were characterized by proximate and ultimate analyses, X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) analyses. The produced syngas was analyzed by online portable gas analyzer and gas chromatography-thermal conductivity detector (GC-TCD). The syngas composition of H2 increased from 3.91 to 4.70% (increased 20.20%), CO increased from 5.73 to 6.30% (increased 10.53%), whereas CO2 decreased from 20.60 to 12.67% (decreased 38.50%) and CH4 concentration increased insignificantly from 0.35 to 0.37% (increased 5.7%) which was happened due to the use of WoodCharcoal and Bi2O3 with EFBpalm oil during gasification. According to the findings, carbon is abundant in WoodCharcoal, which may considerably boost the gasification reactivity with Bi2O3. The yield of syngas (H2 and CO) increased when WoodCharcoal and Bi2O3 were used instead of single EFBppo gasification, indicating that catalyst (WoodCharcoal) and co-catalyst (Bi2O3) have a high potential for thermal decomposition and dehydrogenation of volatile matter. Therefore, catalytic gasification of empty palm fruit bunches will be the prospective energy sources for the production of syngas with the utilization of WoodCharcoal and Bi2O3. [ABSTRACT FROM AUTHOR]

This study is aimed to apply dry anaerobic digestion (DAD) for methane (CH4) enriched biogas production from unsorted organic municipal solid waste (MSW). Cumulative biogas production was monitored for 35 days of operation in batch digesters at fixed feedstock to inoculum (F/I) ratio 2. Anaerobic sludge (AS) and cow manure (CM) were used as inoculum in single and mixed modes. Several process parameters such as inoculum flow pattern (single layer, multilayer, and spiral), digestion temperature (25 to 40 °C), inoculation modes (single and mixed mode), and inoculation proportion (AS:CM = 1:1, 1:2, 1:3, and 2:1) were investigated to determine the optimum DAD conditions to maximize the CH4 laden biogas yield. The study of inoculum flow pattern showed that digester with multilayer inoculum configuration generated the maximum 555 mL cumulative biogas with the production rate of 195 mL/day (at 25 °C). Biogas production rate and cumulative biogas production were found to increase with a rise in temperature and the maximum values of 380 mL/day and 1515 mL respectively were observed at 37 °C. The mixed mode of inoculation containing AS and CM augmented the biogas yield at previously optimized conditions. Final results showed that digester with multilayer inoculum flow pattern at 37 °C produced 1850 mL cumulative biogas with 1256.58 mL CH4/kg volatile solid (VS) when the mixed inoculum was used at the AS:CM—1:2 ratio. Biogas production with this significant amount of CH4 justifies the use of the DAD process for energy (biogas) generation from widely available biomass feedstock (MSW), offering various advantages to the environment. [ABSTRACT FROM AUTHOR]

Enhancing the anode performance is a critical step for improving the power output of MFCs. This study deals with the dual chamber MFCs to increase the power generation using the controlled inoculum in Palm oil mill effluent (POME). Controlled inoculum (CI) was made using the predominant microorganisms such as Pseudomonas aeruginosa , Azospira oryzae , Acetobacter peroxydans and Solimonas variicoloris isolated from palm oil anaerobic sludge (AS) as well as from biofilm of MFC anode operated with AS and identified using BIOLOG gene III analysis, PCR, DGGE and sequencing. Biofilm formation on electrode was investigated by Fourier Transform Infrared spectroscopy (FTIR) and Thermogravimetric analayis (TGA). The MFC operated with Polyacrylonitrile carbon felt (PACF) anode and CI reached the maximum power density of 107.35 mW/m 2 , which was two times higher as compared to MFC operated with usual anaerobic sludge as inoculum. The maximum coulombic efficiency (CE) of 74% was achieved from the MFC with CI, which was 50% higher than the CE with anaerobic sludge. But, it showed lower COD removal efficiency of about 32%, which might be due to the absence of required fermentative microorganisms in CI to utilize POME. The electrochemical activities have been investigated by electrochemical impedance spectroscopy (EIS). EIS and the simulated results showed the significant reduction of charge transfer resistance ( R ct ) by ∼40% during the operation of the cell with CI. EIS results provided evidence that there was a substantial improvement in electron transfer between the microorganisms and the anode with CI. These results demonstrate that the power output of MFCs can be increased significantly using CI. [ABSTRACT FROM AUTHOR]

The study investigated the suitability of waste rubber powder (WRP) use as filler in adhesive formulation for plywood application. Melamine Urea Formaldehyde (MUF) was employed as resin for formulating the wood adhesive. To improve chemical properties and bonding quality of adhesive, WRP was treated by different chemicals like 20% nitric acid, 30% hydrogen peroxide and acetone solution. The treated WRP were analysed by XRD and it showed that inorganic compounds were removed and carbon was remained as major component under the treatment of 20% HNO3. The treatment improved the mechanical properties like shear strength and formaldehyde emission of plywood (high shear strength and low formaldehyde emission). The physico-chemical interaction between the wood, resin and filler was investigated using fourier transform infrared spectroscopic (FTIR) technique and the interactions among N-H of MUF and C=O of wood and WRP were identified. The morphology of wood-adhesive interface was studied by field emission scanning electron microscope (FESEM) and light microscope (LM). It showed that the penetration of adhesives and fillers through the wood pores was responsible for mechanical interlocking. Therefore, chemically treated WRP proved its potential use as filler in MUF based adhesive for making plywood. [ABSTRACT FROM AUTHOR]

Co-cultures of different microorganisms are considered promising inocula for treating palm oil mill effluents (POME) and producing value-added bio-products (e.g., biofuels and fatty acid-derived materials). However, the efficiency of yeast-bacteria co-culture for microbial lipid production through bioremediation of wastewater remains a bottleneck. In this study, the performance of a co-culture for lipid accumulation through POME bioremediation was investigated using a yeast (Lipomyces starkeyi) and a bacterium (Bacillus cereus). A maximum biomass of 8.89 ± 0.33 g/L and lipid production of 2.27 ± 0.10 g/L were achieved by the co-culture inoculum, which were substantially higher than those of the monocultures. Besides, the co-culture inoculum attained a maximum chemical oxygen demand (COD) removal of 83.66 ± 1.9%, while the individual cultures of B. cereus and L. starkeyi obtained 74.35 ± 1.7% and 69.01 ± 2.3%, respectively. The bioremediation efficiency was confirmed by the seed germination index (GI) of Vigna radiata (Mung bean). It was observed that the co-culture inoculum had a higher GI compared to the untreated POME and even the monoculture-treated POME. We argue that the symbiotic association of a yeast-bacteria co-culture in POME could be an attractive approach for achieving maximum biomass as well as lipid production and simultaneous bioremediation of POME. [Display omitted] [ABSTRACT FROM AUTHOR]

Biomass-generated syngas conversion through fermentation is a promising technique for bioethanol production due to increasing demand for clean and sustainable energy. However, lignocellulosic biomass is difficult to degrade wholly, and traditional pretreatment process has several drawbacks. The present study emphasizes on bioethanol production from lignocellulosic biomass-based syngas including the main composition of N 2 (45.58%), CO (22.92%), CO 2 (7.9%), H 2 (13.05%), and CH 4 (1.13%). Field emission electronic microscopic analysis was used to characterize freshly cultured Clostridium butyricum for syngas fermentation and experiment was run in a bioreactor (TFB). The obtained yield of bioethanol was analyzed by nuclear magnetic resonance and gas chromatography-mass spectrometry analyses. For this syngas fermentation, treated syngas was preferred, as most of the Clostridium butyricum grown on best fermentation conditions. The results show that except 0.03% of CO 2 , other gases were dissolved entirely. It is also found that extracted bioethanol was identified by corresponding NMR (1H) spectra of methyle group (CH 3 -), methylene group (–CH 2 –) and hydroxyl group (OH). The yield of bioethanol was 29.94 mmol from 1 L of syngas. Hence, this biomass-generated syngas is the appropriate renewable energy source for the meetup of future energy needs. Image 1 • Syngas fermentation was performed in a tar free bioreactor (TFB). • Syngas and charcoal were used as a substrate of Clostridium butyricum. • Clostridium butyricum is one of the suited microorganisms for bioethanol production. • 500 times higher CFU was found when treated syngas was used instead of untreated syngas. • Yield of bioethanol was 29.94 mmol from 1 L of syngas. [ABSTRACT FROM AUTHOR]

Abstract Lignocellulosic biomass gasification shows a pronounced prospective to replace fossil fuels. In this study, the gasification of coconut shell with charcoal using a 50 kW downdraft reactor was investigated. The controlling parameter of temperature and pressure were used to verify the production of gas during the gasification process with air. The higher contents of cellulose and hemicellulose than lignin in the sample were found to gasify better, as evident from structural analysis. The gasifier produces a combustible gas with a H 2 , CO, CO 2 and CH 4 concentrations of 8.44, 15.38, 5.38 and 1.62 mol.% respectively, at a total flow of air of 30 m3 h−1. The results revealed that 30 wt% charcoal in the feedstock was effectively gasified to generate syngas comprising over 30 mol.% of syngas with a lower heating value of 3.27 MJ/Nm3. Thus, the co-gasification of lignocellulosic biomass with charcoal may contribute to affordable and environmentally friendly syngas energy. Graphical abstract Image 1 Highlights • The gasification of coconut shell using a 50 kW downdraft reactor was investigated. • The variations of pressure and temperature during gasification were controlled. • The high ratio of syngas was observed at the coconut shell and charcoal ratio of 2.3:1. [ABSTRACT FROM AUTHOR]

In this work, palm kernel meal (PKM) and palm shell (PS) were studied as a filler for wood adhesive formulations and their efficiency was compared with existing industrial flour (IF). Melamine urea formaldehyde (MUF) was used as resin for formulating the wood adhesives. The effects of the natural fillers (PKM and PS) on shear strength and formaldehyde emission of plywood were analyzed. The optimum hot press temperature and time were found to be 125 °C and 150 s, respectively. Both PKM and IF influenced the shear strength and formaldehyde emission characteristics, with the optimum concentration of filler being within the range of 13% to 18%. The physico-chemical interaction between the wood, resin and filler was investigated using Fourier transform infrared spectroscopy (FTIR) and the interactions among C˭O groups on PKM and N‒H, O‒H groups on wood and MUF were identified. Apart from the bonding strength, the mechanical interlocking between adhesive and wood was found to be very important for adhesive performance which was dependent on the viscosity of the adhesive which in turn was controlled by the filler concentration. The wood –adhesive interface was examined using light microscopy (LM). [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the synergistic or antagonistic interaction between oral dabigitran etexilate (Pradaxa) and some foods. Methods: Aqueous extracts of sweet orange, cabbage, ginger, green tea, garlic and pineapple were prepared and lyophilized, and total phenolic acids and flavonoid contents evaluated. The residues of the aqueous extracts were given daily to the rats (500 mg/kg dose, oral) 1 h after administration of dabigatran (1.83 mg/kg dose) for 14 days. Bleeding time, International Normalized Ratio (INR), prothrombin time (PT) as well as alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) in blood were measured. Results: Oral administration of Pradaxa with all the test food (except cabbage) significantly increased bleeding time, INR and PT. Pradaxa interaction with cabbage significantly decreased bleeding tendencies but the drug did not produce any major elevation of liver enzyme levels (ALT, AST and ALP). Conversely, significant elevation in ALP level was observed only after aqueous extract of ginger was administered with Pradaxa. Green tea and garlic significantly increased ALT and AST levels. Conclusion: Synergistic interaction occurrs between dabigatran etexilate with the selected foods, but interaction with cabbage antagonistic. [ABSTRACT FROM AUTHOR]

Abstract Artificial photosynthesis has the potential to produce solar fuels from CO 2 and H 2 O using an efficient photocatalyst. Semiconductor with low band gap and high stability is always the right candidate to be used as photocatalyst. Photocatalytic (PC) reduction of CO 2 suffers from slow reaction kinetics and poor yield of product. Photocatalytic reaction in assistance with judicious bias potential is a solution to increase the catalytic activity and reduce the electron/hole (e−/h+) recombination rate. In the present work, a p -type CuFe 2 O 4 was synthesized and used for photoelectrochemical (PEC) CO 2 reduction. The catalyst was characterized by UV-visible spectroscopy (UV-vis), Mott-Schottky (MS), chronoamperometry, X-Ray powder diffraction (XRD), X-Ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). Methanol was found as only product in liquid phase produced by photoelectrochemical reduction of CO 2 at a bias potential of −0.5 V (vs NHE) under light irradiation (at 470 nm). The quantum efficiency and incident photon to current efficiency (IPCE) were found as 14.4% and 5.1% respectively revealed that, CuFe 2 O 4 is a potential photocathode for PEC of CO 2 reduction. Highlights • CuFe 2 O 4 was studied as efficient catalyst for photoelectrochemical reduction of CO 2. • Methanol was formed during the PEC reduction of CO 2 at a bias potential of −0.5 V. • The Faradaic efficiency for methanol production was found 68% in PEC. • PEC showed higher methanol yield compared to photo/electro-catalytic CO 2 reduction. [ABSTRACT FROM AUTHOR]

In this work, p-type CuFe2O4 was synthesized by sol gel method. The prepared CuFe2O4 was used as photocathode catalyst for photoelectrochemical (PEC) CO2 reduction. The XRD, UV-Visible Spectroscopy (UV-Vis), and Mott-Schottky (MS) experiments were done to characterize the catalyst. Linear sweep voltammetry (LSV) was employed to evaluate the visible light (λ>400 nm) effect of this catalyst for CO2 reduction. The band gap energy of the catalyst was calculated from the UV-Vis and was found 1.30 eV. Flat band potential of the prepared CuFe2O4 was also calculated and found 0.27 V versus Ag/AgCl. Under light irradiation in the CO2-saturated NaHCO3 solution, a remarkable current development associated with CO2 reduction was found during LSV for the prepared electrode from onset potential -0.89 V with a peak current emerged at -1.01 V (vs Ag/AgCl) representing the occurrence of CO2 reduction reaction. In addition, the mechanism of PEC was proposed for the photocathode where the necessity of a bias potential in the range of 0.27 to ~ -1.0 V vs Ag/AgCl was identified which could effectively inhibit the electron-hole (e-/h+) recombination process leading to an enhancement of CO2 reduction reactions. [ABSTRACT FROM AUTHOR]

Although exogenous mediators can distinctly enhance the performance of yeast driven microbial fuel cell (MFC), the possibility of mediator's toxicity, environmental risk, and cost are the main challenges facing toward its application in MFCs. Therefore, the use of naturally produced electron shuttles for unmediated yeast would be of great interest since it can solve most of the above-mentioned problems. The present study is to investigate the possibility of the use of electron shuttle producing bacteria Klebsiella pneumonia (K. pneumonia) to boost up the performance of yeast Lipomyces starkeyi (L. starkeyi) driven MFC. The MFCs inoculated with L. starkeyi and K. pneumoniae coculture achieved a maximum power density of 12.87 W/m3 which is about 3 and 6 times higher than that of MFC solely inoculated with pure yeast and bacteria, respectively, demonstrating that the yeast cells have successfully utilized the reduced electron shuttles excreted by the bacteria. The occurrence of the mutualistic interactions was further supported by the CV and EIS results. The findings of this work suggest that the use of mutualistic interaction of yeast and bacteria could be a new way to increase the performance of the MFCs. [ABSTRACT FROM AUTHOR]

In the present work, the wild type Klebsiella variicola was investigated in double chamber microbial fuel cell (MFC) using palm oil mill effluent as substrate which achieved high power density (4.5 W/m 3 ) and coulombic efficiency (63%) while maintaining the moderate chemical oxygen demand (COD) removal efficiency (58%). The effect of biofilm formation on power generation over time was also evaluated and found that an effective biofilm with the discrete distribution of single layer microorganisms can produce high power corresponding to low charge transfer resistance. The growth of biofilm in multilayers consisting of outnumbered dead cells in the vicinity of the electrode surface caused the polarization resistance and diffusion resistance resulting in a sharp drop in the current generation. The removal of multilayer biofilm from the anode surface positively influenced the cell performance which led to a rapid increase in current generation and thus revealed that effective biofilm predominated by live cells can be an emergent factor for achieving maximum performance in MFC. [ABSTRACT FROM AUTHOR]

Hydrolysates of Giant reed ( Arundo donax ) biomass from three different agronomical conditions were used to grow the oleaginous yeast L. Starkey . The agronomical conditions affected the cellulose fraction of biomass, the amount of inhibitors generated during the acid hydrolysis, and the triglyceride yield after the yeast fermentation. Yet, the composition of triglycerides was not affected. Different approaches were developed to reduce the effect of inhibitors. The preliminary dilution of hydrolysates was studied, obtaining the highest values of biomass and lipid yields with a 50% dilution. Alternatively, the hydrolysates were pre-treated by adsorption and overliming. The latter pre-treatment gave the best results. A third approach was offered by the use of pre-adapted yeasts, that were able to grow in the presence of raw hydrolysates. The composition of the microbial triglycerides was compatible with the production of a biodiesel suitable for use as automotive fuel. [ABSTRACT FROM AUTHOR]

Highlights: [•] Catalyst CuO/C was prepared by a novel technique where activated carbon was introduced with nano-sol. [•] The free fatty acid conversion was achieved up to 95% using 8wt% catalysts. [•] High catalytic activity was observed and activity was lost about 20% after four cycles uses. [Copyright &y& Elsevier]

Biohydrogen production from different types of waste biomass using mixed culture inoculum has been an active research area in recent years. Several emerging techniques has been studied targeting to achieve higher efficiency and competitive hydrogen production through the dark fermentation. However, the production of biohydrogen from complex waste biomass meets the setback of lower final product yield due to the low substrate degradation rate. Besides, hydrogen consuming microbes in the mixed culture impede the rate of biohydrogen production. Thus, the waste biomass substrate and microbial inoculum are highly required to pretreat for enhancing system performance. With the aim to gain deeper insight into waste biomass and inoculum pretreatment techniques, this review compiles recently practiced pretreatment techniques with their limitations. The major challenges of these methods and few strategies to overcome these limitations with future directions are discussed in this review. Moreover, the efficiency of a potential nonconventional pretreatment technique such as electroporation (EP) over traditional techniques to degrade the complex waste biomass and reduce the load of hydrogen consuming microbes in the mixed culture consortium was reviewed. This review argued to provide a deeper insight to develop an efficient pretreatment technique by combining traditional techniques and EP for enhancing mixed culture driven biomass-based hydrogen production. [Display omitted] • Substrate degradation is crucial in the fermentative hydrogen (H 2) production. • The H 2 consumers present in the mixed culture inoculum reduce the H 2 yield. • Electroporation (EP) is an efficient pretreatment for complex biomass substrates. • The possible mechanism of the EP to inactivate H 2 consumers is illustrated. [ABSTRACT FROM AUTHOR]

A single-stage sol—gel route was set to entrap yeast cells of Lipomyces starkeyi in a zirconia(ZrO2)matrix, and the remediation ability of the resulting catalyst toward a phenoxy acid herbicide, 4-chloro-2-methylphenoxyacetic acid (MCPA), was studied. It was found that the experimental procedure allowed a high dispersion of the microorganisms into the zirconia gel matrix; the ZrO2 matrix exhibited a significant sorption capacity of the herbicide, and the entrapped cells showed a degradative activity toward MCPA. The combination of these effects leads to a nearly total removal efficiency ( > 97%) of the herbicide at 30 °C within 1 h incubation time from a solution containing a very high concentration of MCPA (200 mg L-1). On the basis of the experimental evidence, a removal mechanism was proposed involving in the first step the sorption of the herbicide molecules on the ZrO2 matrix, followed by the microbial degradation operated by the entrapped yeasts, the metabolic activity of which appear enhanced under the microenvironmental conditions established within the zirconia matrix. Repeated batch tests of sorption/degradation of entrapped Lipomyces showed that the removal efficiency retained almost the same value of 97.3% after 3 batch tests, with only a subsequent slight decrease, probably due to the progressive saturation of the zirconia matrix. [ABSTRACT FROM AUTHOR]

An understanding of the inter-species relationships, especially their metabolic network in a mixed-culture system, is crucial to design an effective inoculum for enhancing the power generation of wastewater fed microbial fuel cell (MFC). In the present study, the influence of microbial mutualistic interactions on the power generation of palm oil mill effluent fed MFCs has been widely investigated by designing several co-culture and mixed culture inoculums. Among the different inoculum compositions, the highest power density of 14.8 W/m3 was achieved by Pseudomonas aeruginosa and Klebsiella variicola co-culture inoculum due to their synergistic relationships which were inter-linked via fermentation-based metabolites. Besides, the interaction of K. variicola and Bacillus cereus positively influenced the power generation resulting in a maximum power density of 11.8 W/m3 whereas the antagonistic relationship between B. cereus and P. aeruginosa resulted in a lower power generation of 1.9 W/m3. The microbial mutualistic interactions were investigated with polarization, cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), as well as by using metabolite and biofilm analysis. It was observed that the synergism between bacteria enhanced power generation through the production of higher electron shuttling mediators and efficient biofilm formation as evidenced by polarization, CV and EIS analysis. In contrast, the antagonistic relationship resulted in production of cell inhibiting metabolites leading to the formation of ineffective biofilm. These findings demonstrate that the synergistic interaction between or within microorganisms is emergent in designing co-culture or mixed-culture inoculum for achieving maximum power generation in MFCs. Unlabelled Image • Microbial synergistic interactions achieved 3 times higher power generation of MFC. • The microbial synergism enhanced production of electron shuttling mediators. • The antagonistic relationship resulted in the production of cell inhibiting metabolites. [ABSTRACT FROM AUTHOR]