High flux carbon fiber cloth membrane with thin catalyst coating integrates bio-electricity generation in wastewater treatment

In this study, a catalytic cathode membrane based on carbon fiber cloth was successfully prepared, and it integrated microbial fuel cell (MFC) with membrane bioreactor (MBR). Nanoparticle Pd-RGO-CoFe2O4 catalyst was synthesized in one-step, using ethylene glycol as reduction agent, and assisted by microwave reduction. It was coated with polyvinylidene fluoride (PVDF) binder on carbon fiber cloth, with followed phase inversion. The formed composite cathode membrane with the blended and fixed Pd-RGO-CoFe2O4 catalyzed bio-electricity generation in coupled MFC/MBR system. Besides its high pure water membrane flux (59,817 LMH bar(-1)) and high conductivity (15.2 x 10(-2) S CM-1), it also performed well in membrane fouling reduction and energy production (683 mW m(-3)). By thinning the PVDF coating from 700 m to 300 ifm, the surface conductivity of the catalyst layer in cathode membrane increased approximately 1000 times (from 3.1 x 10(-6) S CM-1 to 3.3 x 10(-3) S cm(-1)), and it can improve the catalytic activity towards oxygen reduction reaction (ORR). The catalyst in PVDF binder could greatly improve the porosity of membrane. By comparing the ratio of Pd:RGO in catalyst and bio-generation, it was proved that 1:1 ratio was better than 1:2 or 2:1. (C) 2016 Elsevier B.V. All rights reserved.