On-site production of high-purity hydrogen from raw biogas with fixed-bed chemical looping

Bernd Stoppacher*, Thomas Sterniczky, Sebastian Bock, Viktor Hacker

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review


Chemical Looping Hydrogen processes among others, show an outstanding potential for the decentralized conversion of biogas into high-purity hydrogen. For the first time, a 10 kWth fixed-bed chemical looping system has been coupled directly to a 3 MWth biogas digester in the southern region of Austria in the scope of the Austrian research project Biogas2H2. This experimental lab system resembles a blueprint for a potential future industrial system design. A comprehensive parameter study pointed out the influence of relevant process parameters (temperature, O/R ratio, reduction time, steam quantity in oxidation) on hydrogen purity and process efficiency. At the optimal operating point (850 ◦C, O/R 1.2), the process efficiency was comparable to the utilization of synthetic biogas in previous investigations within a deviation of 2.9%. Sulfuric compounds were isolated before entering the chemical looping system in order to avoid harmful contamination of the product hydrogen and performance loss, as investigated in preliminary experiments. The generated hydrogen was characterized online by ppm-range gas analysis and exhibited a product gas quality of up to 99.998%, with residual CO and CO2 as only contaminants. The fulfillment of the carbon mass balance within a mean deviation of 9% proved the correct quantification. The results indicate that coupling fixed-bed chemical looping systems to biogas plants enables the production of a fuel cell grade hydrogen and a sufficient process efficiency in upgrading local available biogenic and agricultural residuals to high-purity hydrogen.
Original languageEnglish
Article number115971
JournalEnergy Conversion and Management
Publication statusE-pub ahead of print - 13 Jul 2022


  • Chemical looping, Decentralized hydrogen production, Biogas conversion, Reformer steam iron cycle
  • Biogas conversion
  • Chemical looping
  • Reformer steam iron cycle
  • Decentralized hydrogen production

ASJC Scopus subject areas

  • Energy Engineering and Power Technology
  • Fuel Technology
  • Nuclear Energy and Engineering
  • Renewable Energy, Sustainability and the Environment

Fields of Expertise

  • Mobility & Production

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