Scaling-up of microbial electrosynthesis with multiple electrodes for in situ production of hydrogen peroxide

Summary Microbial electrosynthesis system (MES) has recently been shown to be a promising alternative way for realizing in situ and energy-saving synthesis of hydrogen peroxide (H2O2). Although promising, the scaling-up feasibility of such a process is rarely reported. In this study, a 20-L up-scaled two-chamber MES reactor was developed and investigated for in situ and efficient H2O2 electrosynthesis. Maximum H2O2 production rate of 10.82 mg L−1 h−1 and cumulative H2O2 concentration of 454.44 mg L−1 within 42 h were obtained with an input voltage of 0.6 V, cathodic aeration velocity of 0.045 mL min−1 mL−1, 50 mM Na2SO4, and initial pH 3. The electrical energy consumption regarding direct input voltage was only 0.239 kWh kg−1 H2O2, which was further much lower compared with laboratory-scale systems. The obtained results suggested that the future industrialization of MES technology for in situ synthesis of H2O2 and further application in environmental remediation have broad prospects.
Graphical Abstract
Highlights • Up-scaled microbial electrosynthesis with multiple electrodes to synthesize H2O2 • The H2O2 yield was higher than that of laboratory-scale systems using graphite cathode • Energy consumption was lower than that of laboratory-scale (bio)electrochemical systems • Systematic evaluation of the influence of operating parameters on H2O2 production
Electrochemistry; biotechnology; engineering; materials science