Hydrogen generation from bamboo biomass using enzymatic hydrolysis and subsequent microbial electrolysis in a single chamber microbial electrolysis cell

Abstract

Sustainable, economical. and clean energy production technologies acutely needed abundant supply of raw materials (biomass) and superior process engineering techniques to deliver the desired throughput. In this endeavour, here we demonstrated the utilization of lignocellulose (Bambusa bambos) by successive enzymatic treatment and microbial electrolysis in a single chamber MEC for generating clean fuel-hydrogen. In addition, we studied MEC (V=400 mL) by modifying an anode (graphene with 100 cm2 area) with monodisperse iron oxide nanoparticles (IONPs). Enzymatically (10% w/w laccase) pretreated Bambusa bambos with 40.31% reduced lignin was subjected to batch hydrolysis (20% w/w enzyme-to-substrate ratio) using cellulase. The glucose produced (99.54 ± 4 mg/dL) after 96 h of incubation was further operated in single chamber MEC equipped with highly efficient IONPs coated electrodes for hydrogen production. Engineering parameters namely-applied voltage (0.6-1.0 V) and mixing characteristics (0–400 rpm) were also investigated to improve the system performance. The MEC with IONPs coated anode offered hydrogen production efficiency 1.14 times higher as compared to MEC with the uncoated anode. The maximum hydrogen production of 0.02 g (224 mL) per gram of biomass was obtained in MEC with the coated anode at an applied voltage of 0.8 V under the influence of moderate mixing (200 rpm).