skip to main content


Title: Development and testing of a PEM SO 2-depolarized electrolyzer and an operating method that prevents sulfur accumulation

The hybrid sulfur (HyS) cycle is being developed as a technology to generate hydrogen by splitting water, using heat and electrical power from a nuclear or solar power plant. A key component is the SO 2-depolarized electrolysis (SDE) cell, which reacts SO 2 and water to form hydrogen and sulfuric acid. SDE could also be used in once-through operation to consume SO 2 and generate hydrogen and sulfuric acid for sale. A proton exchange membrane (PEM) SDE cell based on a PEM fuel cell design was fabricated and tested. Measured cell potential as a function of anolyte pressure and flow rate, sulfuric acid concentration, and cell temperature are presented for this cell. Sulfur accumulation was observed inside the cell, which could have been a serious impediment to further development. A method to prevent sulfur formation was subsequently developed. As a result, this was made possible by a testing facility that allowed unattended operation for extended periods.
 [1] ;  [1] ;  [1] ;  [1]
  1. Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)
Publication Date:
Report Number(s):
Journal ID: ISSN 0360-3199; PII: S0360319915021370
Grant/Contract Number:
Accepted Manuscript
Journal Name:
International Journal of Hydrogen Energy
Additional Journal Information:
Journal Volume: 40; Journal Issue: 39; Journal ID: ISSN 0360-3199
Research Org:
Savannah River Site (SRS), Aiken, SC (United States)
Sponsoring Org:
USDOE Office of Nuclear Energy (NE)
Country of Publication:
United States
08 HYDROGEN; electrolysis; hybrid sulfur cycle; SO2-depolarized electrolysis; sulfuric acid
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1250047