Microbial electrolysis: Novel biotechnology for hydrogen production from biomass

Abstract

Driven by the world-wide energy crisis, global interest in hydrogen production -continues to increase. Currently, over 95% of the hydrogen supply in the USA is derived from nonrenewable materials, including coal, oil, and natural gas. Remediation of environmental stress related to fossil fuel use requires hydrogen production from renewable energy sources, such as solar, wind, and biomass. A recently invented microbial electrolysis technology demonstrates a new avenue for sustainable hydrogen production from renewable biomass. It has potential to become an economically feasible approach for hydrogen production due to its high hydrogen yield compared to fermentative hydrogen production and much lower energy requirement (about 10% in theory) compared to hydrogen production via water electrolysis. In this chapter, we begin with an introduction of microbial electrolysis cells (MECs) and the stoichiometry and energetics, followed by a section on the microorganisms in MECs and their plausible electron transfer mechanisms. The state-of-art designs, operation, and evaluation of MECs are also discussed.