Search

Background: The use of Polysulfone (PSf) as membrane material for dialysis therapy is becoming more common. However, the PSf membrane can cause the adsorption of blood proteins followed by the adhesion of platelets, destruction of red blood cells, and thrombus formation. One of the biggest challenges in creating membranes for hemodialysis (HD) applications is ensuring biocompatibility. Therefore, to maintain the biocompatibility of PSf membranes, further modifications are necessary. Methods: In this study, the performance and biocompatibility of PSf membranes were improved by the impregnation of TiO2‐hydroxyapatite composite as an additive. The TiO2‐hydroxyapatite composite was first synthesized via sintering at 1200°C, and then a dope solution composed of pristine PSf polymer solution in N‐Methyl‐2‐pyrrolidone solvent (NMP) and different wt% ratios of the synthesized composite were prepared, and resultant membranes were fabricated using a film applicator via a phase inversion scheme using water as a non‐solvent exchange medium. The synthesized composite was characterized using SEM, EDX, and XRD techniques. Results: The FTIR analysis confirmed the weak interaction of PSf polymer with the hydroxyapatite moiety of the composite. The interaction of the synthesized composite within the membrane matrix was evaluated via leaching ratio results. The hydrophilicity, pore profile, and pure water permeation flux rates were also determined. The results of the biocompatibility study showed that membranes based on TiO2‐hydroxyapatite composite had reduced adsorption of BSA protein by 34.41% as well as less than 5% hemolysis ratio. Additionally, the study displayed thrombus formation ranging from 2.08% to 8.69%, respectively. The dialysis results indicated that compared with the original PSf membrane, the TiO2‐hydroxyapatite composite showed high clearance rates for urea (73.81%) and creatinine (72.13%) solutes, respectively. Conclusion: Therefore, blending TiO2‐hydroxyapatite composite in the PSf membrane significantly improved the biocompatibility and removal ability of uremic solutes. [ABSTRACT FROM AUTHOR]

In this study, ceria nanoparticles (NPs) and deep eutectic solvent (DES) were synthesized, and the ceria-NP's surfaces were modified by DES to form DES-ceria NP filler to develop mixed matrix membranes (MMMs). For the sake of interface engineering, MMMs of 2%, 4%, 6% and 8% filler loadings were fabricated using solution casting technique. The characterizations of SEM, FTIR and TGA of synthesized membranes were performed. SEM represented the surface and cross-sectional morphology of membranes, which indicated that the filler is uniformly dispersed in the polysulfone. FTIR was used to analyze the interaction between the filler and support, which showed there was no reaction between the polymer and DES-ceria NPs as all the peaks were consistent, and TGA provided the variation in the membrane materials with respect to temperature, which categorized all of the membranes as very stable and showed that the trend of stability increases with respect to DES-ceria NPs filler loading. For the evaluation of efficiency of the MMMs, the gas permeation was tested. The permeability of CO2 was improved in comparison with the pristine Polysulfone (PSF) membrane and enhanced selectivities of 35.43 (α CO2/CH4) and 39.3 (α CO2/N2) were found. Hence, the DES-ceria NP-based MMMs proved useful in mitigating CO2 from a gaseous mixture. [ABSTRACT FROM AUTHOR]

Membrane technology promises a highly economical and efficient solution for CO2 separation. Many polymeric membranes have been reported in the past for the separation of gases specially to remove CO2 from natural gas and low‐pressure flue‐gas streams. The performance of membranes can be tailored by dispersing nanofillers in a polymeric matrix to produce mixed‐matrix membranes (MMMs). This not only adds mechanical strength to membranes but also reduces compaction of the polymeric layer at high pressure and maintains high performance. Halloysite nanotubes (HNTs) gained attention in gas separation technology and due to their tubular structure have been used in a variety of applications in biomedical, coating, composite, and electronic industries. However, very little but conclusive literature and reviews are available to indicate that functionalized and non‐functionalized HNTs can improve the performance of MMMs for efficient CO2 capture. The current status and gaps for potential applications of HNTs‐based membranes for gas separation are identified and reviewed. [ABSTRACT FROM AUTHOR]

The carbon dioxide (CO2) separation can be enhanced by using modified materials like a deep eutectic solvent (DES) modified mesoporous silica SBA-15 in polymeric support i.e polysulfone via mixed matrix membranes (MMMs). The pure SBA-15 and DES are potential candidates for the CO2 capturing and their combination has not been reported yet. In this work, a fresh DES was synthesized by combining equal concentrations of Decanoic acid and choline chloride by mass. MMMs were fabricated by DES functionalized SBA-15 (DES-SBA) filler. The DES-SBAbased polymeric MMMs of different compositions, from 5% to 20% with the difference of five each, were developed and subjected to the gas permeation analysis to evaluate relative selectivities and permeabilities of membranes. The DES-SBA-based MMMs were characterized by SEM and FTIR to obtain distribution analysis of filler in the polymer matrix as well as the cross-sectional and surface morphology and the structural analysis of membranes, respectively. The gas permeation evaluations have been utilized to mixed and pure gas samples and the findings of selectivities for CO2/N2 and CO2/CH4 and permeabilities of synthesized MMMs are being reported. The performance of the MMMs has been enhanced via functionalization of SBA15 by DES as compared to the neat polysulfone (PSF) based simple membrane. [ABSTRACT FROM AUTHOR]

The growing demand for energy resources and the increase in greenhouse gas (GHG) emissions has given biofuels a lot of attention. Liquid biofuels can be a significant alternative for the transport sector. Generally, biofuels are categorized into four generations based on the feedstock. This review reports the availability, economic feasibility, and potential of biofuel feedstock in global scenario. Feedstock for first‐generation biofuel comprises edible resources impacting the food supply. Second generation biofuels are based on different residual materials and nonedible fuel crops. Cost and technological limitations for commercialization hinders this option. Microalgae are the feedstock for third generation biofuels providing the highest yield compared to the other two generations. A scale‐up to commercial level is not possible as this requires further development. Genetically modified microorganisms are used as a feedstock for fourth generation biofuel production with the highest possible yield. Third and fourth generation biofuels have potential to replace fossil fuels. This review recommends certain suggestions for sustainable biofuel production. [ABSTRACT FROM AUTHOR]

4 Commercial status of bioethanol dehydration to bioethylene Ethylene from ethanol dehydration was first produced on the commercial scale in 1913 at Elektrochemische Werke GmbH in Bitterfeld, Germany ([133]). The catalyst activity and product selectivity depends on the kind of alcohol, kind of catalyst and process conditions, while the trend of alcohol dehydration observed in this research work was as follows: 2-propanol > l-propanol > ethanol, in accordance with the relative stabilities of the corresponding carbenium ions. Keywords: bioethanol; bioethylene; catalyst; dehydration; techno-economic feasibility EN bioethanol bioethylene catalyst dehydration techno-economic feasibility 185 207 23 02/07/22 20220201 NES 220201 1 Introduction The rise in oil prices, environmental issues due to toxic emissions caused by the combustion of fossil fuel and depletion of fossil fuel resources have a demand for an alternative pathway to produce green energy from waste streams ([69]; [74]; [101]; [189]). Another possibility is that three processes can co-occur such as ethanol dehydration to ethylene, ethanol transformation to ether or ether dehydration to ethylene as shown in Figure 7 ([30]; [114]; [161]). 5 Pathways and mechanisms of bioethanol dehydration to bioethylene During the middle of the previous century, much work has been conducted by different researchers to study the reaction mechanism of ethanol conversion to ethylene by dehydration in the presence of various catalysts ([49]; [71]; [82]; [110]; [159]; [166]). [Extracted from the article]

In the current study, a phase inversion scheme was employed to fabricate hydroxyapatite (HA)/polysulfone (PSF)‐based asymmetric membranes using a film applicator with water as a solvent and nonsolvent exchanging medium. Fourier Transform Infrared (FTIR) and X‐ray diffraction (XRD) spectroscopic studies were conducted to confirm the bonding chemistry and purity of filler. The inherent thick nature of PSF generated sponge‐like shape while the instantaneous demixing process produced finger‐like pore networks in HA/PSF‐based asymmetric membranes as exhibited by scanning electron microscope (SEM) micrographs. The FTIR spectra confirmed noncovalent weak attractions toward the polymer surface. The leaching ratio was evaluated to observe the dispersion behavior of HA filler in membrane composition. Hydrophilicity, pore profile, pure water permeation (PWP) flux, and molecular weight cutoff (MWCO) values of all formulated membranes were also calculated. Antifouling results revealed that HA modified PSF membranes exhibited 43% less adhesion of bovine serum albumin (BSA) together with >86% recovery of flux. Membrane composition showed 74% total resistance, out of which 60% was reversible resistance. Biocompatibility evaluation revealed that the modified membranes exhibited prothrombin time (PT), and thrombin time (TT) comparable with typical blood plasma, whereas proliferation of living cells over membrane surface proved its nontoxic behavior toward biomedical application. The urea and creatinine showed effective adsorption aptitude toward HA loaded PSF membranes. [ABSTRACT FROM AUTHOR]

An active and intelligent starch-based biodegradable food packaging system is developed in this work. The growing environmental protection concerns have motivated researchers to look for biodegradable yet sustainable products for food packaging. The packaging is able to resist against undesirable bacterial attack and color-change response due to pH change in food. Polyvinyl alcohol and starch are cross-linked with Glutaraldehyde to improve their mechanical strength. Propolis Extract (PE) and anthocyanin (ATH) were added as an active and intelligent material, respectively. Different film formulations were prepared by varying concentration of PE. All film formulations were characterized by SEM, FTIR and XRD. The results proved good compatibility of the film mixture. The mechanical strength and other physical properties like water vapor transmission rate, moisture retention capability, swelling degree and biological leaching ability were investigated. Films containing 20% PE showed the best results alongside maximum mechanical strength of 15.9 MPa. Furthermore, the same formulation has shown maximum zone of inhibition of 25 mm and 20 mm against E. Coli and MRSA, respectively. Moreover, there was a clear color-change response when films were immersed in different pH solutions ranging from 1 to 14. Finally, to validate the potential application of prepared film formulations, films were tested on pasteurized milk and a color-change response is observed along with the anti-bacterial activity. Hence, this active and intelligent food packaging system is capable of inhibiting and alerting food spoilage. [ABSTRACT FROM AUTHOR]

Carbonate apatite/hydroxyapatite (CO3Ap/HAP) additive was obtained by calcination of wasted chicken bones at 900°C. Intermolecular attraction exists between CO3Ap/HAP additive and blended polysulfone (PSF) polymer. Electron dispersive X‐ray (EDX) and FTIR analysis were carried out to check the elemental composition and bonding chemistry of prepared additive. The instantaneous demixing process generated consistent finger‐like networks in CO3Ap/HAP/PSF‐based composite membranes while sponge‐like structure was shown by PSF as revealed by SEM images. The increase in weight % of additive loading is also confirmed by EDX analysis. Furthermore, the interaction mechanism of CO3Ap/HAP additive with polysulfone medium was analyzed by FTIR exploration. The water absorption experiment defined a 93% expansion in hydrophilic performance. Change in porosity occurs with additive loading and pure water permeation flux improved up to 11 times. Approximately, antifouling results revealed that 87% of water flux was recovered after treating with a protein solution, whereas a 30% improvement in antifouling capability in case of bovine serum albumin solution occurred. In vitro cytotoxicity, and clotting times study was carried out to evaluate virulent behavior and anticoagulation activity of formulated membranes. [ABSTRACT FROM AUTHOR]

A significant amount of glycerol has been generated by the epidemic increment in several biodiesel industries globally, which should be utilized for the biodiversity of biodiesel. The synthesis of Solketal‐acetone glycerol as a possible fuel additive is one of the most crucial glycerol recovery paths. State‐of‐the‐art reviews on batch and continuous processes to produce Solketal and possible reaction mechanisms are presented. The design of reactors and catalysts is taken into consideration and the factors influencing the yield of the Solketal process are discussed in detail. Finally, conclusions with future recommendations are reported. The utility of glycerol for acetals and ketals is of current importance for scientists seeking to find the best working conditions by testing the different catalysts, reactants, temperatures, and reactor designs. [ABSTRACT FROM AUTHOR]

Membrane science is a state-of-the-art environmentally green technology that ascertains superior advantages over traditional counterparts for CO2 capture and separation. In this research, mixed matrix membranes (MMMs) comprising cellulose acetate (CA) with various loadings of bentonite (Bt) clay were fabricated by adopting the phase-inversion technique for CO2/CH4 and CO2/N2 separation. The developed pristine and MMMs were characterized for morphological, thermal, structural, and mechanical analyses. Several techniques such as scanning electron microscopy, thermogravimetric analysis, Fourier transformed infrared spectroscopy, and nano-indentation investigations revealed the promising effect of Bt clay in MMMs as compared to pristine CA membrane. Nano-indentation test identified that elastic modulus and hardness of the MMM with 1 wt. loading was increased by 64% and 200%, respectively, compared to the pristine membrane. The permeability decreased with the incorporation of Bt clay due to uniform dispersion of filler attributed to enhanced tortuosity for the gas molecules. Nevertheless, an increase in gas separation performance was observed with Bt addition up to 1 wt. loading. The opposite trend prevailed with increasing Bt concentration on the separation performance owing to filler agglomeration and voids creation. The maximum value of ideal selectivity (CO2/CH4) was achieved at 2 bar pressure with 1 wt. % Bt loading, which is 79% higher than the pristine CA membrane. For CO2/N2, the ideal selectivity was 123% higher compared to the pristine membrane with 1 wt. % Bt loading at 4 bar pressure. [ABSTRACT FROM AUTHOR]

The production of energy in Pakistan as a developing country mainly depends on consumption of fossil fuels, which are the main sources of greenhouse gas (GHG) emissions. These emissions can be mitigated by implementing carbon capture and storage (CCS) in running plants. An overview of the current and future potentials of Pakistan for CCS is provided, indicating a great potential for this technology to capture CO2 emissions. The amine CO2 capture process as the most mature procedure is currently applied in many oil and gas companies in Pakistan, which can be employed to capture CO2 from other industries as well. Pakistan has a great CO2 storage potential in oil, gas, and coal fields and in saline aquifer as well as significant resources of Mg and Ca silicates suitable as feedstock in the carbon mineralization process. For further development and implementation of CCS technologies in Pakistan, economic and policy barriers as the main obstacles should be alleviated. [ABSTRACT FROM AUTHOR]

Environmental concerns due to excessive use of synthetic or petroleum-based materials have encouraged scientists to develop novel, sustainable, and multifunctional material using abundant lignocellulosic biomass. In this work, a study was conducted on the isolation of cellulose from wheat straw using two different methods: acidified sodium chlorite and alkaline hydrogen peroxide. A comparative study was carried out based on the yield and properties of extracted cellulose. The final product (after treatments) was characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA) for the identification of properties. Both the treatments isolated pure white color cellulose. However, the yield of cellulose isolated through acidified sodium chlorite treatment (81.4%) was higher than alkaline hydrogen peroxide treatment (79%). Moreover, no huge difference was observed in the crystallinity and thermal properties of extracted cellulose. [ABSTRACT FROM AUTHOR]

The synthesis of a nanofluid from multiwalled carbon nanotubes (MWCNTs) and Kapok seed oil by a one‐step method is reported. The nanofluid showed excellent stability of nanoparticle dispersion in the base fluid. Furthermore, this study deals with the prediction of the thermal conductivity of the MWCNTs‐kapok seed oil nanofluid. To improve the prediction of the thermal conductivity of the nanofluid, the artificial neural network (ANN) computing approach was used with different algorithms including the back‐propagation, Levenberg‐Marquardt, and genetic algorithm (GA). Finally, the ANN‐GA model is recommended for the prediction of thermal conductivity with higher accuracy. [ABSTRACT FROM AUTHOR]

Deca-dodecasil 3 rhombohedral (DDR3) membrane has received much attention in CO2 separation from small gas molecules because of its molecular sieving property and stable characteristics. Therefore, the present work is focusing on the utilization of previously fabricated membrane (synthesized in 3 days as reported in our previous work) to study the effect of hydrocarbons and its durability at the previously optimized conditions. Subsequently, gas permeation study was conducted on the DDR3 membrane in CO2 separation from small gas molecules and it was found that the permeance of H2, CO2, N2, and CH4 decreased in the order of H2 > CO2 > N2 > CH4, according to the increase in kinetic diameter of these gas molecules. Besides, it was observed that the ideal selectivities of the gas pairs decreased in the sequence of CO2/CH4 > CO2/N2 > H2/CO2. On the other hand, it was found that the presence of hydrocarbon impurities in the gas mixture containing CO2 and CH4 has directly affected the performance of DDR3 membrane and contributed to the losses of CO2 permeability, CH4 permeability, and CO2/CH4 selectivity of 39.1%, 14.8%, and 4.2%, respectively. Consequently, from the stability test, the performance of DDR3 membrane remained stable for 96 h, even after the separation testing using CO2 and CH4 gas mixture containing hydrocarbon impurities. [ABSTRACT FROM AUTHOR]

This study was conducted to analyze the adsorption efficiency of lignin/alginate/hydroxyapatite composite beads for the removal of copper Cu(II) and nickel Ni(II) ions from an aqueous solution. For this purpose, lignin, alginate and hydroxyapatite (HAp) composite was prepared in the form of lignin/alginate/hydroxyapatite composite beads. Adsorbents were synthesized in three different ratios by mixing lignin/alginate/hydroxyapatite and sodium alginate in distilled water (25–30 ml) which was then added dropwise to the calcium chloride (CaCl2 ) solution to form its lignin/alginate/ hydroxyapatite composite beads. Synthesized beads were characterized using X-ray powder diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and thermogravimetric analysis. The effect of various experimental parameters such as contact time, pH, the initial concentration of Cu(II) and Ni(II) and adsorbent dose on adsorption capacity was investigated. Kinetic and isotherm data confirmed that the pseudo-first-order model and Langmuir isotherm were best fitted to experimental data. An increase in the adsorption capacity of heavy metals from an aqueous solution was observed with the increase in lignin percentage in beads. The maximum adsorption capacity for Cu(II) and Ni(II) was 79.67 and 71.18 mg/g, respectively for C3 (60%) lignin. Reusability study of lignin/alginate/hydroxyapatite beads showed 79% removal efficacy after four successive adsorption-desorption cycles. The results showed that lignin/alginate/hydroxyapatite composite beads can be used as promising environmentally benign adsorbent for the removal of heavy metal ions from an aqueous solution. [ABSTRACT FROM AUTHOR]

Membrane technology has emerged as a leading tool worldwide for effective CO2 separation because of its well‐known advantages, including high surface area, compact design, ease of maintenance, environmentally friendly nature, and cost‐effectiveness. Polymeric and inorganic membranes are generally utilized for the separation of gas mixtures. The mixed‐matrix membrane (MMM) utilizes the advantages of both polymeric and inorganic membranes to surpass the trade‐off limits. The high permeability and selectivity of MMMs by incorporating different types of fillers exhibit the best performance for CO2 separation from natural gas and other flue gases. The recent progress made in the field of MMMs having different types of fillers is emphasized. Specifically, CO2/CH4 and CO2/N2 separation from various types of MMMs are comprehensively reviewed that are closely relevant to natural gas purification and compositional flue gas treatment [ABSTRACT FROM AUTHOR]

Treatment of pandrug resistant (PDR) Escherichia coli strain is the leading causative agent of bovine mastitis worldwide. Hence, becoming a potential threat to veterinary and public health. Therefore, to control the infection new nontoxic, biocompatible antimicrobial formulation with enhanced antibacterial activity is massively required. Current study was planned to synthesize chitosan coated titanium dioxide nanoparticles (CS-NPs coated TiO2). Coating was being done by chitosan nanoparticles (CS-NPs) using ionic gelation method. Aqueous solution of Moringa concanensis leaf extract was used to synthesize titanium dioxide nanoparticles (TiO2 NPs). The synthesized nanoformulations were characterized by using XRD, SEM, and FTIR. X-ray diffraction (XRD) analysis indicated the crystalline phase of TiO2 NPs and CS-NPs coated TiO2 NPs. Scanning Electron Microscopy (SEM) confirmed spherical shaped nanoparticles size of chitosan NPs ranging from 19–25 nm and TiO2 NPs 35–50 nm. Thesize of CS-NPs coated TiO2 NPs was in the range of 65–75 nm. The UV-Vis Spectra and band gap values illustrated the red shift in CS-NPs coated TiO2 NPs. Fourier transform infrared (FTIR) spectroscopy confirmed the linkages between TiO2 NPs and chitosan biopolymer, Zeta potential confirmed the stability of CS-NPs coated TiO2 NPs by showing 95 mV peak value. In-vitro antibacterial activity of CS-NPs coated TiO2 NPs and Uncoated TiO2 NPs was evaluated by disc diffusion method against PDR strain of E. coli isolated from mastitic milk samples. The antibacterial activity of all the synthesized nanoformulations were noted and highest antibacterial activity was shown by CS-NPs coated TiO2-NPs against pandrug resistant (PDR) E. coli strain with the prominent zone of inhibition of 23 mm. Morphological changes of E. coli cells after the treatment with MIC concentration (0.78 μg/ml) of CS-NPs coated TiO2 NPs were studied by transmission electron microscopy TEM showedrigorous morphological defectand has distorted the general appearance of the E. coli cells. Cytotoxicity (HepG2 cell line) and hemolytic (human blood) studies confirmed nontoxic/biocompatible nature of CS-NPs coated biologically synthesized TiO2 NPs. The results suggested that biologically synthesized and surface modified TiO2 NPs by mucoadhesive polysaccharides (e.g. chitosan) coating would be an effective and non-toxic alternative therapeutic agent to be used in livestock industry to control drug resistant veterinary pathogens. [ABSTRACT FROM AUTHOR]

Mild steel sample was selected from acid storage tanks used in industry as a substrate, and two advanced technological polymeric resin-based coatings were developed, designated as LAM-P resin based which is LAM-P/FR coating and LAM-V resin based which is LAM-V/FR coating. These coatings were applied over steel samples by using the hand lay-up process. FTIR test was conducted to confirm complete curing, and SEM analyses were used to investigate surface morphology. A series of electrochemical tests were performed in acidic environment (mixed acid solution 56% H2SO4 + 26% HNO3 + 18% H2O by weight). The results indicated successful development of LAM-P/FR and LAM-V/FR to obtain coatings with desirable characteristics such as anticorrosion, thickness, adhesion, stability, charge store and more resistance to acidic environments. EIS data for mixed acid storage media demonstrated that LAM-V/FR coating has higher strength in mixed acid solution, higher values of impedance and phase shift, higher value of Rpore, and low value of Cc; corrosion rate percentage reduction is 96% of LAM-P/FR and 99.96% of LAM-V/FR compared to bare mild steel sample. The outcomes of this study can lead to assist in design guidelines for anticorrosive coating for industrial applications. [ABSTRACT FROM AUTHOR]