(546b) Prevention of Sulfur Formation in Hybrid Sulfur Electrolyzer

The Hybrid Sulfur Cycle for producing hydrogen uses an electrolyzer with a sulfur dioxide depolarized anode. The cell voltage is much lower than for conventional electrolysis, however during testing of a Hybrid Sulfur electrolyzer a layer of sulfur frequently formed between the cathode and the membrane of the membrane electrode assembly in the electrolyzer. This layer increased cell voltage and eventually damaged the cell. Savannah River National Laboratory has developed an operating method to prevent sulfur formation. This method has been successfully tested over periods as long as ten days. To allow extended testing 24 hours a day the test facility has been heavily automated.