It has been proposed that compact ceramic heat exchangers can be used for high temperature, corrosive applications. This paper discusses the development and optimization of a micro-channel heat exchanger for the decomposition of sulfuric acid as part of the hydrogen producing Sulphur-Iodine (SI) thermo-chemical cycle. The optimization process combines thermal-hydraulic and structural modelling, materials testing, component fabrication and performance testing. Based on a shell and plate design, modular stacks of microchannel containing plates form the primary heat exchange surfaces in a compact arrangement. These modules enable scaling to commercial-scale processes; the microchannels enhance the heat transfer while maintaining low pressure drops within the system. The ceramic materials provide for long-life applications. The feasibility of this compact heat exchanger was assessed through thermal and mechanical models and by flow testing of as-fabricated components. The results of this design effort with its associated performance goals and development status will be reported.