초록
<P><B>Abstract</B></P> <P>Hydrogen peroxide (H<SUB>2</SUB>O<SUB>2</SUB>) as a strong oxidant, is widely used in various chemical industries and environmental remediation processes. In this study, we developed an innovative method for cost-effective production of H<SUB>2</SUB>O<SUB>2</SUB> by using a microbial reverse-electrodialysis electrolysis cell (MREC). In the MREC, electrical potential generated by the exoelectrogens and the salinity-gradient between salt and fresh water were utilized to drive the high-rate H<SUB>2</SUB>O<SUB>2</SUB> production. Operational parameters such as air flow rate, pH, cathodic potential, flow rate of salt and fresh water were investigated. The optimal H<SUB>2</SUB>O<SUB>2</SUB> production was observed at salt and fresh water flow rate of 0.5 mL min<SUP>−1</SUP>, air flow rate of 12–20 mL min<SUP>−1</SUP>, cathode potential of −0.485 ± 0.025 V (vs Ag/AgCl). The maximum H<SUB>2</SUB>O<SUB>2</SUB> accumulated concentration of 778 ± 11 mg L<SUP>−1</SUP> was obtained at corresponding production rate of 11.5 ± 0.5 mg L<SUP>−1</SUP> h<SUP>−1</SUP>. The overall energy input for the synthesis process was 0.45 ± 0.03 kWh kg<SUP>−1</SUP> H<SUB>2</SUB>O<SUB>2</SUB>. Cathode potential was the key factor for H<SUB>2</SUB>O<SUB>2</SUB> production, which was mainly affected by the air flow rate. This work for the first time proved the potential of MREC as an efficient platform technology for simultaneous electrosynthesis of valuable chemicals and utilization of salinity-gradient energy.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Microbial reverse-electrodialysis electrolysis cell for H<SUB>2</SUB>O<SUB>2</SUB> production. </LI> <LI> High yield synthesis of H<SUB>2</SUB>O<SUB>2</SUB> from oxygen reduction without external power supply. </LI> <LI> Salinity-gradient between salt and fresh water drove the high-rate H<SUB>2</SUB>O<SUB>2</SUB> production. </LI> <LI> Recycling the salt and fresh water for the production with less water consumption. </LI> <LI> Cathode potential as key for H<SUB>2</SUB>O<SUB>2</SUB> production can be adjusted by air flow rate. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>