Efficient production of hydrogen peroxide in microbial reverse-electrodialysis cells coupled with thermolytic solutions

H 2 O 2 was produced at an appreciable rate in microbial reverse-electrodialysis cells (MRCs) coupled with thermolytic solutions, which can simultaneously capture waste heat as electrical energy. To determine the optimal cathode and membrane stack configurations for H 2 O 2 production, different catalysts, catalyst loadings and numbers of membrane cell pairs were tested. Carbon black (CB) outperformed activated carbon (AC) for H 2 O 2 production, although AC showed higher catalytic activity for oxygen reduction. The optimum CB loading was 10 mg/cm 2 in terms of both the H 2 O 2 production rate and power production. The optimum number of cell pairs was determined to be three based on a tradeoff between H 2 O 2 production and capital costs. A H 2 O 2 production rate as high as 0.99 ± 0.10 mmol/(L·h) was achieved with 10 mg/cm 2 CB loading and 3 cell pairs, where the H 2 O 2 recovery efficiency was 52 ± 2% and the maximum power density was 780 ± 37 mW/m 2 . Increasing the number of cell pairs to five resulted in an increase in maximum power density (980 ± 21 mW/m 2 ) but showed limited effects on H 2 O 2 production. These results indicated that MRCs can be an efficient method for sustainable H 2 O 2 production.