Anti-Foulant Ultrafiltration Polymer Composite Membranes Incorporated with Composite Activated Carbon/Chitosan and Activated Carbon/Thiolated Chitosan with Enhanced Hydrophilicity

Abstract

A rapid increase in population worldwide is giving rise to the severe problem of safe drinking water availability, necessitating the search for solutions that are effective and economical. For this purpose, membrane technology has shown a lot of promise but faces the challenge of fouling, leading to a reduction in its lifetime. In this study, ultrafiltration polyethersulfone membranes were synthesized in two different concentrations, 16% wt. and 20% wt., using the phase inversion method. Chitosan and activated carbon were incorporated as individual fillers and then as composites in both the concentrations. A novel thiolated chitosan/activated carbon composite was introduced into a polyethersulfone membrane matrix. The membranes were then analyzed using Attenuated Total Reflection–Fourier-Transform Infrared spectroscopy(ATR-FTIR), Scanning Electron Microscopy (SEM), optical profilometry, gravimetric analysis, water retention, mechanical testing and contact angle. For membranes with the novel thiolated chitosan/activated carbon composite, Scanning Electron Microscopy micrographs showed better channels, indicating a better permeability possibility, reiterated by the flux rate results. The flux rate and bovine serum albumin flux were also assessed, and the results showed an increase from 105 L/m2h to 114 L/m2h for water flux and the antifouling determined by bovine serum albumin flux increased from 23 L/m2h to 51 L/m2h. The increase in values of water uptake from 22.84% to 76.5% and decrease in contact angle from 64.5 to 55.7 showed a significant increase in the hydrophilic character of the membrane.

Water Treatment Using High Performance Antifouling Ultrafiltration Polyether Sulfone Membranes Incorporated with Activated Carbon

“…The highest flux for PES UF membranes has been shown by mAC filler added membranes which is in agreement with reported results [ 27 ]. The highly porous structure, large surface area and hydrophilic character of mAC makes the membranes more suitable candidate for UF process.…”

“…The adsorption of BSA on the nanocomposite membrane surface was decreased because of electrostatic repulsion. In another study, AC, Chitosan and thiolated chitosan/AC has been seperately incorporated as filler in PES UF membranes to increase its hydrophilicity and reduce fouling [ 27 ]. The pure water flux and BSA flux both were high for AC added polymer composite membrane.…”

Response Surface Methodology Modeling Correlation of Polymer Composite Carbon Nanotubes/Chitosan Nanofiltration Membranes for Water Desalination

“…These results confirmed that the incorporation of chitosan in the PES matrix even in the presence of hydrophobic MWNTs could appreciably tune the hydrophilic character of the membrane samples. 39 As discussed in Section 3.8, the contact angle measurement results were related to the surface roughness values as measured from the AFM analysis.…”

Effects of Benzalkonium Chloride Contents on Structures, Properties, and Ultrafiltration Performances of Chitosan-Based Nanocomposite Membranes

“…However, chitosan membranes have low stability and mechanical strength. Therefore, it is necessary to modify their manufacturing process [ 28 , 29 ]. The addition of polyethylene glycol (PEG) and carbon nanotubes (CNT) has been shown to significantly increase the permeability and mechanical strength of chitosan membranes [ 30 , 31 ].…”