Process Biochemistry, Vol.102, 213-219, 2021
Influence of Trace Metals concentration on Methane generation using Microbial Electrochemical Systems
The biomethane generation in microbial electrosynthesis systems (MESs) was affected by the addition of trace metals (TMs) during biocatalyst's metabolic activity. The functional role of various TMs (Mg2+, Fe2+, Ni2+, Zn2+, Co2+, Mn2+, and Mo2+) in regulating the CH4 production potential of a biocatalyst was evaluated under three different ranges of TM concentrations, and their performances were compared with the control operation (no trace metals). The TM level in a relatively medium concentration range exhibited the best efficiency and could enhance the CH4 production and currents generation by 3.9 and 7.7 folds higher than the values from the control. Cyclic voltammogram profiles depicted increment in redox catalytic currents during MES operation with TMs and also supported the involvement of mediators towards CH4 generation. The optimum TM concentrations could enhance MES performance as a constituent of ferredoxin and hydrogenase linked to energy metabolism.