Catalytic combustion of the retentate gas from a CO2/H-2 separation membrane reactor for further CO2 enrichment and energy recovery

摘要

The CCR (catalytic combustion reaction) of the retentate gas, consisting of 90% CO2 and 10% H-2 obtained from a CO2/H-2 separation membrane reactor, was investigated using a porous Ni metal catalyst in order to recover energy and further enrich CO2. A disc-shaped porous Ni metal catalyst, namely Al[0.1]/Ni, was prepared by a simple method and a compact MCR (micro-channel reactor) equipped with a catalyst plate was designed for the CCR. CO2 and H-2 concentrations of 98.68% and 0.46%, respectively, were achieved at an operating temperature of 400 degrees C, GHSV (gas-hourly space velocity) of 50,000 h(-1) and a H-2/O-2 ratio (R/O) of 2 in the unit module. In the case of the MCR, a sheet of the Ni metal catalyst was easily installed along with the other metal plates and the concentration of CO2 in the retentate gas increased up to 96.7%. The differences in temperatures measured before and after the CCR were 31 degrees C at the product outlet and 19 degrees C at the N-2 outlet in the MCR. The disc-shaped porous metal catalyst and MCR configuration used in this study exhibit potential advantages, such as high thermal transfer resulting in improved energy recovery rate, simple catalyst preparation, and easy installation of the catalyst in the MCR. (C) 2015 Elsevier Ltd. All rights reserved.