Enrichment of activated sludge for enhanced hydrogen production from crude glycerol

Cristiano Varrone, Silvia Rosa, Floriana Fiocchetti, Barbara Giussani, Giulio Izzo, Giulia Massini, Antonella Marone, Antonella Signorini, Aijie Wang

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37 Citations (Scopus)


Enriched activated sludge that can effectively convert crude glycerol into bio-hydrogen was selected by an eco-biotechnological approach, in very strict conditions, using biodiesel-derived glycerol as the only carbon source. The thus obtained functional consortium was characterized by the genera Klebsiella, Escherichia/Shigella and Cupriavidus. During enrichment, the dominant metabolic end-product shifted from a 1,3 propanediol to ethanol, with a concomitant increase of the hydrogen yield from 0.18 ± 0.003 to 0.66 ± 0.06 mol/mol and an almost five-fold increase of the hydrogen production. Glycerol degradation efficiency showed an increase of around 50%. In optimized and upscaled conditions it was possible to obtain a hydrogen production rate of 2960 mL H2/L/day ± 185 at a near stoichiometric yield (of 0.90 mol/mol ± 0.01), with a carbon recovery of almost 90%, both in sterile and non-sterile conditions. Glycerol was almost totally degraded (degradation efficiency of 97.42% ± 0.98), independently of the glycerol type used. Copyright © 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.
Original languageEnglish
Pages (from-to)1319 - 1331
Number of pages13
JournalInternational Journal of Hydrogen Energy
Issue number3
Publication statusPublished - 6 Feb 2013


All Science Journal Classification (ASJC) codes

  • Renewable Energy, Sustainability and the Environment
  • Fuel Technology
  • Condensed Matter Physics
  • Energy Engineering and Power Technology

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