Hydrogen production through polyoxometalate catalysed electrolysis from biomass components and food waste

Abstract

Electrolysis from biomass is a promising process for hydrogen generation from biomass and biowaste that is still unexplored. The paper used lignocellulosic biomass components and food waste (banana and cucumber peels) as feedstocks to explore hydrogen generation through an H-type proton exchange membrane electrolytic cell. Polyoxometalates (PMo12) were employed as a catalyst and charge carrier during the pre-treatment stage in the biomass degradation process. Electrochemical characterisations were conducted in a potential range of 0–1.20 V to analyse the electrochemical reaction behaviour at the anode. To assess the impact of temperature on the hydrogen yield rates, the electrolysis was conducted at both room temperature (19 °C) and a higher temperature (80 °C). Results show that the maximum hydrogen produced in the first hour was 7.8 mL per gram of biomass. With an electrical potential of 1.20 V and a temperature of 80 °C, the hydrogen yield rate of glucose was three times higher than that of the individual biomass components, i.e., cellulose, lignin, hemicellulose, and starch. The volume of hydrogen yielded from banana peel and cucumber was 49.2 mL and 39.6 mL, respectively. The overall conversion efficiency was calculated as the weight percentage ratio of the hydrogen contained in cucumber and banana peels and the hydrogen collected was 10 % and 17 %, respectively, suggesting the need to identify solutions to extract the hydrogen content from biomass material further.

Keywords

• Electrolysis
• Biomass
• Food waste
• Hydrogen production
• Polyoxometalate catalyst