Simultaneous Coproduction of Hydrogen and Ethanol in Anaerobic Packed-Bed Reactors

Abstract EN

This study evaluated the use of an anaerobic packed-bed reactor for hydrogen production at different hydraulic retention times (HRT) (1–8 h).

Two reactors filled with expanded clay and fed with glucose (3136–3875 mg L−1) were operated at different total upflow velocities: 0.30 cm s−1 (R030) and 0.60 cm s−1 (R060).

The effluent pH of the reactors was maintained between 4 and 5 by adding NaHCO3 and HCl solutions.

It was observed a maximum hydrogen production rate of 0.92 L H2 h−1 L−1 in R030 at HRT of 1 h.

Furthermore, the highest hydrogen yield of 2.39 mol H2 mol−1 glucose was obtained in R060.

No clear trend was observed by doubling the upflow velocities at this experiment.

High ethanol production was also observed, indicating that the ethanol-pathway prevailed throughout the experiment.