Modification of PAN electrospun nanofiber membranes with g-C3N4 nanotubes/carbon dots to enhance MBR performance.

This study is dedicated to the enhancement of electrospun polyacrylonitrile (PAN) nanofiber membranes for their application in membrane bioreactor (MBR) processes. The improvement is achieved through the incorporation of graphitic carbon nitride nanotubes/carbon dots (g-C3N4 NT/CDs) and subsequent heat post-treatments at varying temperatures. Notably, the hot-pressing methodology effectively mitigates surface roughness and significantly reduces issues related to peeling during nanofiber experimentation. Our results demonstrate that the introduction of 0.5 wt% of g-C3N4 NT/CDs leads to a substantial enhancement in water flux. In particular, nanocomposite membranes subjected to hot-pressing at 90 °C for 10 min exhibited an impressive flux recovery ratio (FRR) of 70%. Furthermore, the heat-treated nanocomposite membranes exhibited remarkable antifouling properties and significantly reduced fouling rates when compared to their heat-treated bare counterparts. This study underscores the noteworthy potential of g-C3N4 NT/CDs-modified PAN nanofiber membranes to substantially elevate MBR performance, firmly positioning them as highly promising candidates for critical applications in the domains of water and wastewater treatment. However, it is imperative to underscore that the existing written material necessitates a comprehensive overhaul to align with the provided structural framework.

A review of cellulose-based derivatives polymers in fabrication of gas separation membranes: Recent developments and challenges.

Due to low-cost, sustainability and good mechanical stability, cellulose-based materials are frequently used in fabrication of polymeric gas separation membrane as potential carbohydrate polymers to substitute traditional petrochemical-based materials. In this review, the performance of cellulose-based polymeric membranes i.e. cellulose acetate, cellulose diacetate, cellulose triacetate, ethyl cellulose and carboxymethyl cellulose in the separation of different gases were investigated. This review paper provides the main features and advantages in the fabrication of cellulose-based gas separation membranes. The influence of the functionalization of cellulose on gas separation and permeability performance of related membranes is considered. Influence of different modification procedures such as blending with polymers, nanomaterials and ionic liquids on the gas separation ability of cellulose-based membranes were reviewed. Moreover, a brief inquiry of the potential of cellulose-based gas separation membranes for industrial applications, by examining the performance of different cellulose derivatives and identifying potential strategies for membrane modification and optimization are given, along with the current restrictions and the future perspectives are discussed.

Determination of the effect of proteoliposome concentration on Aquaporin Z incorporated nanofiltration membranes.

We report on the fabrication of AqpZ immobilized flat sheet membranes. The effects of interfacial polymerization conditions as well as proteoliposome concentration were evaluated. Commercial AqpZ were used as positive control for cloned AqpZ. Specific permeate flux of membranes at higher proteoliposome concentrations increased up to 25 times higher than thin film composite membranes; however; MgSO4 rejection is lowered almost to 1.5%. FTIR and SEM confirm immobilization of proteoliposomes. Thermal analysis showed that increasing proteoliposome concentration has no positive effect on the incorporation of proteoliposomes into polyamide structures. On the contrary, at lower proteoliposome concentrations, incorporation of proteoliposomes was found better. When combined membrane performances were compared in terms of specific permeate flux; MgSO4 and humic rejection and flux recovery after humic acid filtration, the performance of cloned AqpZ incorporated membranes (having 0.1 mg/mL proteoliposome concentration and polyamide formed with 2 min piperazine reaction time) improved 1.7 times regarding TFC membranes. According to the results, increasing proteoliposome concentration did not improve nanofiltration membrane performance. On the contrary, lower proteoliposome concentrations were found to be more effective in increasing membrane performance.