FINAL REPORT ON GDE GAP CELL

Herman, D. ; Summers, W. ; Danko, E.

Savannah River Site (S.C.)

关键词: Hydrogen Production;    Diffusion;    Oxidation;    Electrochemical Cells;    Anodes;   

DOI  :  10.2172/964999
RP-ID  :  SRNL-OS-2009-00070
RP-ID  :  DE-AC09-08SR22470
RP-ID  :  964999

美国|英语

来源: UNT Digital Library

【 摘 要 】

A project has been undertaken to develop an electrochemical cell and support equipment for evaluation of a gas diffusion electrode-based, narrow-electrolyte-gap anode for SO{sub 2} oxidation in the hydrogen production cycle of the hybrid sulfur (HyS) process. The project supported the HyS development program at the Savannah River National Lab (SRNL). The benefits of using a gas diffusion electrode in conjunction with the narrow anolyte gap are being determined through electrochemical polarization testing under a variety conditions, and by comparison to results produced by SRNL and others using anode technologies that have no anolyte gap. These test results indicate that the NGA cell has low resistance suitable for use in the HyS electrolyzer, exhibits good efficiency at high current densities compared to the direct feed HyS electrolyzer, and indicates robust performance in extended testing over 65 hours. Seepage episodes were mostly caused by port clogging, which can be mitigated in future designs through minor modifications to the hardware. Significant reductions in sulfur crossover have not yet been demonstrated in the NGA configuration compared to in-house direct feed testing, but corroborative sulfur layer analysis is as yet incomplete. Further testing in a single-pass anolyte configuration is recommended for complete evaluation of steady-state electrochemical efficiency and SO{sub 2} crossover in the narrow gap configuration.