Fabrication and characterization of hybrid poly (vinyl alcohol) based proton exchange membrane for energy generation from wastewater in microbial fuel cell system

Producing energy and utilizing it efficiently in industry and agriculture are key components of healthy growth of the economy of a country. Microbial fuel cells (MFCs) are a form of technology that can be utilized on a big scale to treat wastewater and generate electricity simultaneously. The cost of proton exchange membranes (PEM) in MFCs can be prohibitively high, and operational concerns such as biofouling and fuel crossover significantly limit the device's practical application in wastewater energy harvesting. As a remedy, the construction of an alternate membrane composed of polyvinyl alcohol (PVA) crosslinked with sulfosuccinic acid (SSA) was dedicated to enhancing the proton conductivity and mechanical property of PVA membrane as PEM in MFC. In this study, there are several types of membranes that have been used with varying compositions of SSA (1-5 wt.%). As indicated by the controlled water uptake and swelling ratio, as well as better thermo-mechanical stability, crosslinking the PVA membrane resulted in a decrease in hydroxyl groups due to the carboxyl group of SSA and the formation of the ester bond. The addition of zirconium phosphate (ZrP) in various compositions ranging from 1 to 5 wt.% has boosted the crosslinked membrane further, whereas the hybrid membrane with PVA/5 wt.% SSA/5 wt.% ZrP that was selected resulted in a greater power density of 1.49 mW/m2, comparable to that of commercial Nafion membrane (1.85 mW/m2). The PVA/SSA/ZrP membrane exhibits its promise as a separator in future MFCs due to its compatible power performance with those commercial membranes.