Enhanced biohydrogen production in a membraneless single-chamber microbial electrolysis cell during high-strength wastewater treatment: Effect of electrode materials and configurations

The selection of better electrode material and studies of the electrocatalytic activities of the electrodes are crucial to increasing biohydrogen production in a microbial electrolysis cells (MEC). In the present work, we studied biohydrogen production and electrocatalytic activities using a membraneless single-chamber MEC fed with high-strength wastewater, using different electrode materials (metal and carbon electrode), configurations and electrode distance. The electro-fermentation (EF) process showed a significantly higher biohydrogen production and COD removal, compared to conventional dark fermentation reactor (DF). The maximum hydrogen production rate (HPR) obtained was 314 m3 H2/m3R.d with an overall biohydrogen recovery (rH2) of 340% using the electrode configuration stainless steel 304 pleated mesh 60 as anode and stainless steel 304 flat mesh 60 as cathode at 4 cm of electrode distance. The onset potential for the hydrogen evolution reaction (HER) with metal electrode was significantly lower than carbon electrode.(c) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Automated summary

The selection of better electrode material and studies of the electrocatalytic activities of the electrodes are crucial to increasing biohydrogen production in a microbial electrolysis cells (MEC). In this study, biohydrogen production and electrocatalytic activities were investigated using a membraneless single-chamber MEC fed with high-strength wastewater, employing different electrode materials, configurations, and distances. The electro-fermentation (EF) process exhibited significantly higher biohydrogen production and COD removal compared to the conventional dark fermentation reactor (DF). The onset potential for the hydrogen evolution reaction (HER) was significantly lower with metal electrodes than with carbon electrodes.