Publications

Sulfuric acid decomposition for the sulfur based thermochemical cycles

Moore, Robert; Vernon, Milton E.; Parma, Edward J.; Pickard, Paul; Rochau, Gary E.

In this work, we describe a novel design for a H2SO 4decomposer. The decomposition of H2SO4 to produce SO2is a common processing operation in the sulfur-based thermochemical cycles for hydrogen production where acid decomposition takes place at 850°C in the presence of a catalyst. The combination of high temperature and sulfuric acid creates a very corrosive environment that presents significant design challenges. The new decomposer design is based on a bayonet-type heat exchanger tube with the annular space packed with a catalyst. The unit is constructed of silicon carbide and other highly corrosion resistant materials. The new design integrates acid boiling, superheating, decomposition and heat recuperation into a single process and eliminates problems of corrosion and failure of high temperature seals encountered in previous testing using metallic construction materials. The unit was tested by varying the acid feed rate and decomposition temperature and pressure.