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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]

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]