High-Temperature Energy Storage: Kinetic Investigations of the CuO/Cu2O Reaction Cycle

Thermochemical energy storage (TCES) is considered a possibility to enhance the energy utilization efficiency of various processes. One promising field is the application of thermochemical redox systems in combination with concentrated solar power (CSP). There, reactions of metal oxides are in the focus of research, because they allow for an increase in the process temperature. The reaction system CuO/Cu2O has been reported as a suitable candidate for TCES. For proper development and modeling of combined CSP–TCES processes, reliable kinetic data are necessary. This work studies the reduction of CuO and the oxidation of Cu2O under isothermal and isokinetic conditions. The reactions are analyzed using a simultaneous thermal analysis (STA) and a lab-scale fixed-bed reactor. The reaction behavior shows significant differences between both analyses. To develop kinetic models, the non-parametric kinetic (NPK) approach is used. This model-free approach is expanded by the Arrhenius correlation to increase the app...