2007 Annual Meeting

(519f) Theoretical Yield Hydrogen Production from Starch and Water by An in Vitro Synthetic Enzymatic Pathway

Authors

Evans, B. R. - Presenter, Oak Ridge National Laboratory
Mielenz, J. R. - Presenter, Oak Ridge National Lab
Hopkins, R. C. - Presenter, University of Georgia


The future hydrogen economy offers a compelling energy vision but there are four main obstacles: hydrogen production, storage, and distribution, and high costs of fuel cells, as well as a safety concern. Hydrogen production from less costly renewable abundant biomass can both decrease reliance on fossil fuels and achieve net greenhouse gas emissions, but current chemical and biological means suffer from low hydrogen yields or/and severe reaction conditions. Here we demonstrated a multiple enzymatic reaction consisting of 13 enzymes and NADPH for producing hydrogen from starch and water as C6H10O5 (l) + 7 H2O (l) -> 12 H2 (g) + 6 CO2 (g) [PLOS ONE, 2007,2, e456]. The overall process is spontaneous and unidirectional because of a negative Gibbs free energy. The unique features, such as mild reaction conditions (30C and atmospheric pressure), high hydrogen yields, likely low production costs ($~2/kg H2), and a high energy-density carrier starch (14.8 H2-based mass%), provides perfect opportunities of mobile applications. With technology improvements and integration with fuel cells, this technology also solves the challenges associated with hydrogen storage, distribution, infrastructure and safety in the hydrogen economy.