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Updated: Aug 23, 2026

Hydrogen Production and Utilization in a Membrane Reactor
Published on: March 10, 2023
Hydrogen production from propionate by Rhodopseudomonas capsulata
1Laboratory of Environmental Biotechnology, Department of Chemistry, University of Science & Technology of China, Hefei, Anhui, 230026, China.
Abstract:
Hydrogen production from propionate at various concentrations by Rhodopseudomonas capsulata, a purple nonsulfur bacterium, was studied at a temperature of 31 degrees C, a pH of 7.0, and an illumination intensity of 3000 Lux. Among the six levels of propionate, 3.84 g/L was found to be the optimum propionate concentration for H2 production in terms of substrate utilization efficiency, H2 percentage, cumulative H2 production, and H2 yield. A modified Gompertz equation was able to describe properly the production of H2 from propionate. A comparative study of H2 production with acetate, propionate, and butyrate at 40 mM showed that, as a substrate for H2 production by R. capsulata, propionate was better than butyrate, but less favorable than acetate.
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