Implementation of Chitosan modified ultrafiltration hollow fiber as proton exchange membrane of ml-scale microbial fuel cells

The study investigated the modification of polyethersulfone (PES), polyvinylidene fluoride (PVDF), and polyacrylonitrile (PAN) hollow fiber membranes using a chitosan solution as the proton exchange membrane for microbial fuel cells (MFCs). Firstly, the performance of the modified PES membrane using ۱, ۲, and ۳% of chitosan in ۰.۱ M acetic acid coating were inspected. Chitosan coating decreased the internal resistance and enhanced the electricity generation of the MFCs. The maximum power and current densities of ۷۵۵.۲۰۲ mW/m۲, and ۵۵۲۵.۴۲ mA/m۲ were achieved for ۳% chitosan-coated PES (PES-۳%chi) compared to ۶۲۹.۵۳۳ mW/m۲ and ۳۲۳۷.۷۹ mA/m۲ for pristine PES membrane. Thereafter, application of a ۳% chitosan coating over the PAN and PVDF membranes exhibited excessive improvement in the bioelectricity generation and wastewater treatment efficiency of the MFCs. The PAN-۳%chi achieved the uppermost power and current densities of ۷۶۵.۱۴۷ mW/m۲ and ۸۲۹۷.۴۶ mA/m۲, which were ۱.۷ and ۲.۶ higher than the PAN membrane (۴۵۰.۶۷۵ mW/m۲ and ۳۲۱۶.۵۶ mA/m۲). The electricity generation of the PVDF membrane was enhanced by ۵.۳ times (۳۳۷.۱۳۴ mW/m۲ and ۲۷۲۰.۱۶ mA/m۲) after the addition of ۳% chitosan, likely due to the improvement in hydrophilicity and proton conductivity. The COD removal efficiencies of ۴۲.۴۱, ۴۰.۵۵, and ۳۶.۱۱% were obtained by PAN-۳%chi, PES-۳%chi, and PVDF-۳%chi membranes, respectively, which were ۳.۵۳, ۴.۰۱, and ۵.۵۳ times higher than the values obtained by their pristine unmodified samples.

Keywords:

Microbial fuel cell , Chitosan , Hollow fiber membrane , domestic wastewater , Wastewater treatment