The efficient treatment of landfill leachate using a novel osmotic microbial fuel cell system employing forward...

The application of osmotic microbial fuel cell (OsMFC) for landfill leachate treatment is limited by rising catholyte pH, due to slow proton migration from the anode to the cathode. Such issue is potentially solved by forward osmosis (FO) membrane through incorporating proton-conducting medium. The study focused on elucidating the efficacy of this novel OsMFC system in treating landfill leachate, which integrated the custom-made FO membranes incorporating different types of proton-conducting medium. Specifically, proton migration was significantly boosted in the OsMFC system utilizing FO-2 membrane by doping heterogeneously metal-organic frameworks (MOFs). The FO-2 membrane with superior proton-conducting performance was fabricated by incorporating equal amido-MIL-101(Cr) and sulfo-MIL-101(Cr) into the polyamide layer formed on top of polysulfone substrate by interfacial polymerization method. The facilitating proton transport results from the synergistic action of formed acid-base pairs and hydrophilic nanochannels between the two types of heterogeneous microporous MOFs. Results revealed that the OsMFC employing FO-2 membrane attained a maximum power density of 5.82 ± 0.47 W·m^-3, representing a 71.68 % increase compared to the system using a commercial membrane. Furthermore, the salinity dilution rate of simulated seawater and extracted volume of clean water from landfill leachate were approximately 2∼3 folds those achieved with the commercial membrane. Additionally, the OsMFC with the FO-2 membrane exhibited superior pollutant degradation performance and the highest pollutant retention rates. The efficient landfill leachate treatment performance was attributed to the facilitated proton migration and improved water flux enabled by the proton-conducting medium. Therefore, this research demonstrated a promising innovative application for the efficient and green treatment of landfill leachate.