Preparation and modification of thin film composite membrane using a bulky dianhydride monomer

Abstract

One of the most effective methods to modify thin film composite (TFC) membranes is changing the chemistry of top selective layer by different monomers and different monomer concentrations. Herein, we report the preparation of modified TFC membranes using a pyromellitic dianhydride (PMDA) mixed with organic phase (trimesoyl chloride) and meta phenylene diamine (MPD).By manipulating the PMDA amount in organic phase, the structures and chemical compositions of polyamide selective layer could be modified. It was realized that the presence of PMDA could result in a modified membrane with higher surface roughness, less dense selective layer, more surface charge density, and better hydrophilic properties and consequently less fouling. The optimum PMDA concentration was found 0.05 wt%, such that the obtained membrane had 35.6 L m À2 h À1 pure water flux, about 1.6-fold higher than the reference membrane with similar salt rejection. Fouling intensity for the reference membrane was 38.1%, while for the modified membranes it decreased to 16.7%.

Diving boldly into COVID‐19 contaminated wastewater: Eyes at nanotechnology‐assisted solutions

“…The biological processes have depended on the cultivation of microorganisms such as bacteria, fungi, or algae to convert organic matter to nitrogen gas and other environment-friendly (benign) biodegradation products under aerobic and anaerobic conditions in wastewater treatment. 121,122 According to Feng et al, granular sequencing batch reactors, MBRs, moving bed biofilm reactors, biological aerobic and anaerobic digesters are the most popular technology systems. It is worth mentioning that most studies have concentrated on sequencing batch reactors and MBRs.…”

Development of braid reinforced hollow fiber membranes as both ultrafiltration and nanofiltration membranes: Effect of pore forming additive on structure and performance

“…14 Ultrafiltration (UF) membranes made of polyethersulfone (PES) or polysulfone (PSf) polymer are commonly used as a support layer for composite membranes because of their high thermal and mechanical durability, chemical resistance, and financial viability. 15,16 Most commercially used NF membranes are made of thin-film composite (TFC) flat sheet membranes placed in a spiral wound module. 17 Despite the many benefits of hollow fiber membranes over flat sheet membranes, controlling reaction solutions flow and properly removing them during interfacial polymerization is more difficult in hollow fibers.…”

“…The NF membranes are consisting of a porous support layer that generates mechanical support and polyamide (PA) active layer formed by the interfacial polymerization method that used trimesoyl chloride (1,3,5‐benzenetricarbonyl trichloride) (TMC) and piperazine anhydrous (PIP) to provide ultra‐thin negative surface charges at which separation occurs 14 . Ultrafiltration (UF) membranes made of polyethersulfone (PES) or polysulfone (PSf) polymer are commonly used as a support layer for composite membranes because of their high thermal and mechanical durability, chemical resistance, and financial viability 15,16 . Most commercially used NF membranes are made of thin‐film composite (TFC) flat sheet membranes placed in a spiral wound module 17 .…”