Measured steam conversion and chemical kinetics in a hydrolysis packed bed reactor for hydrogen production

Abstract

Active research on the thermochemical Cu-Cl cycle is providing a promising potential for sustainable hydrogen production. The thermal efficiency of the hydrolysis reaction can drastically influence the viability and cost of the cycle. In the Cu-Cl cycle, the extent of the hydrolysis reaction has a major effect on cycle efficiency. Un-reacted superheated steam is difficult to efficiently separate from the gaseous reactor product, potentially dissipating a significant amount of thermal energy. In this paper, the upper limit of steam conversion in a copper (II) chloride reactor is investigated and new experimental results are presented. The experimental apparatus is designed to provide superheated steam, at 375°C, to excess CuCl2 and provide sufficient reaction time to approach the steam conversion limit. This is achieved by introducing a low steam flowrate to a packed bed reactor with six meters of packing solids. Variable reaction temperature, residence time, and flow rate are investigated for their effect on reaction extent and chemical kinetics. This research provides useful new data to effectively design and integrate a Cu-Cl hydrogen production cycle. © 2012 Published by Elsevier Ltd.