ABSTRACT:
The work described in this report was accomplished during the period October 1, 1978-March 31, 1979, on a DOE-sponsored program aimed at developing efficient and economic thermochemical cycles for hydrogen production from a variety of high-temperature energy sources such as fusion, fission, anc;l solar energy. Most of the effort was applied to a study of the Los Alamos Scientific Laboratory (LASL) hybrid bismuth sulfate cycle. The work included a conceptual design of the cycle, made to obtain performance parameters, and experimental work done to verify the design conditions. Key findings were:
• A 50% efficiency was obtained when an improved cycle design was coupled to a fusion energy source at 1500 K. The improved design was based on a reduced endothermic requirement for Bi2Os · 2SOs decomposition and a lower voltage for SO2 electrolysis that should result at lower acid concentrations.
• Experimental results showed an endothermic heat requirement of + 172 kJ/mol for the decomposition of Bi2Os·2SOa to Bi2Os·SOs and SOa.
• Reaction times for bismuth sulfate decomposition were determined as a function of temperature. At 1240 K,