Limitations of bio-hydrogen production by anaerobic fermentation process: An overview

Turning organic wastes into hydrogen (H2) by using anaerobic fermentative technology is an ideal concept because this can accomplish both waste treatment and energy recovery objectives. However, H2 production using anaerobic fermentative approaches faces a fundamental limitation of poor H2 production yield (i.e. < 4 mol H-2 per mol of hexose). This article gives an over-view on the limitations of bio-H2 production using fermentative processes. Fundamental microbiology and thermodynamic of the processes are discussed.