Continuous CuCl₂ Hydrolysis in the Six-Step Cu–Cl Thermochemical Cycle for Green Hydrogen Production

Abstract

Thermochemical production of green hydrogen by using a closed loop Cu−Cl cycle has been established by us and is patented. This article outlines a noncatalytic reaction of cupric chloride with steam in a continuous reactor as part of our ongoing research on the ICT-OEC copper−chlorine (Cu−Cl) cycle for thermochemical hydrogen generation. The kinetics of the hydrolysis reaction of cupric chloride to copper oxide was examined by the effect of different operating parameters such as the mole ratio of steam to cupric chloride, the reaction temperature, the particle size of CuCl 2 , and time on stream study. The product, copper oxide, was well characterized using different techniques. The chemical and XRD analysis of the product compositions revealed the optimum Steam to CuCl 2 molar ratio. After the optimization, product conversion and selectivity are 76.7% and 99.07%, respectively. Based on the kinetics on a mini-pilot scale, possible explanations are suggested. Reactors in a series system reduce the steam requirements as a result increase the HCl concentration in the final product. The energy demand is notably reduced from 1.169 to 0.0653 kW when utilizing reactors in a series configuration with heat recovery, which was simulated using Aspen Plus software. The findings are useful in scaling up equipment in the thermochemical Cu−Cl cycle for hydrogen production.