The thermochemical IS process for hydrogen production involves the use of highly corrosive sulfuric and hydriodic acids at high temperature and pressure, and the development of corrosion-resistant materials for main components is therefore crucial to process development. This paper concerns the development of a sulfuric acid transfer pump, an important component in transferring high-temperature concentrated sulfuric acid in the sulfuric acid decomposition step of the IS process. A reciprocating plunger pump made of SiC ceramics and common metal alloys was designed to meet the required corrosion resistance, thermal resistance and compressive strength for the transfer of high-temperature concentrated sulfuric acid. The pump was test-fabricated, and its performance in an IS test plant with a hydrogen production capacity of 30 m(3)/h was verified in terms of the pressure resistance and the transfer performance.