Thermochemical processes for hydrogen production. Progress report, January 1--July 31, 1977. [Sulfuric acid-hydrogen bromide cycle]

The Thermochemical Hydrogen Program at the Los Alamos Scientific Laboratory is continuing its investigation of practical schemes to decompose water thermochemically for production of hydrogen. Current efforts were directed to experimental studies of reactions relevant to the sulfuric acid-hydrogen bromide thermochemical cycle. The use of insoluble bismuth sulfate as a means of concentrating aqueous sulfuric solutions is also under investigation. Preliminary calculations show a significant cycle efficiency increase if solid sulfate and subsequent sulfur trioxide decomposition steps replace the sulfuric acid concentration and decomposition steps proposed in other cycles.