Solar hydrogen production via copper oxide - Copper sulfate water splitting cycle

Abstract

In this paper computational thermodynamics modeling of the solar H2 production via twostep thermochemical copper oxide - copper sulfate (CO-CS) water splitting cycle is reported. In this cycle, the first step corresponds to the exothermic oxidation of copper oxide via SO2 and H2O producing CuSO4 and H2 and second step is related to the endothermic reduction of CuSO4 into CuO, SO2, and O2. The CuO and SO2 produced in the second step can be recycled to the step 1 and hence, reutilized for the production of H2 via water splitting reaction. The equilibrium compositions for the CuSO4 thermal reduction and water splitting steps were determined by performing thermodynamic analysis and are reported here. Furthermore, exergy analysis was performed to determine the cycle efficiency and solar to fuel energy conversion efficiency attainable without heat recuperation.