An investigation into polymer blending, plasticization and cross-linking effect on the performance of chitosan-based composite proton exchange membranes for microbial fuel cell applications

Abstract

Chitosan (Cs) is one of the biopolymers increasingly employed to prepare proton exchange membranes (PEMs) in microbial fuel cells (MFCs). In this work, Cs is blended with three other natural or synthetic biopolymers including alginate (Alg), carboxymethylcellulose (CMC) and polyvinyl alcohol (PVA) followed by cross-linking/ plasticization with phosphoric acid, sulfuric acid, 3-(Trimethoxysilyl)propyl methacrylate (TMSPM), and glycerol (Gly), techniques have been examined as enhancement to neat Cs PEM in MFC system. The obtained membranes were characterized by FTIR, XRD, FESEM, mechanical properties, sorption study, and cation exchange capacity studies. The performance of the cross-linked and plasticized blended Cs membranes was evaluated in bio-power production and COD removal with municipal wastewater as an anolyte in the typical 2-chambered MFCs. The performance of MFC attached Cs PEM with the power density of 237 mW/m3 was increased up to 365 mW/m3 when it installed Cs/Alg. Therefore, after plasticization, power densities were decreased; however, COD removal of 23% for Cs/Alg membrane was increased up to 88% for phosphoric acid cross-linked Cs/Alg. The results confirm that this material could be a promising enhanced alternative to neat Cs, as a PEM in MFCs.