Experimental and simulation studies of the production of renewable hydrogen through ethanol steam reforming in a large-scale catalytic membrane reactor

The diversification of hydrogen production sources has tremendous energy and environmental implications, making ethanol steam reforming (ESR) an essential process that requires further investigation. Hence, the purpose of this work is to investigate the performance of a large-scale catalytic membrane reactor (CMR) used to enhance the efficiency of ESR by the in-situ removal of H2 from the reactor module. The reactor consisted of a tubular membrane located at the center and surrounded by a commercial nickel-based catalyst. A thin, defect-free composite asymmetric membrane was prepared as a Pd/Au/Pd/Au structure, then characterized and tested under reacting conditions. Ethanol steam reforming was conducted under different conditions such as steam-to-carbon ratios, liquid hourly space velocities (LHSV), operating pressures and temperatures. A 1-D model and a 2-D computational fluid dynamics (CFD) model were developed, validated experimentally and used to explore further the features of this reaction. The CMR module was operated for 300 h showing 100% conversion of ethanol in all conditions and producing H2 with a purity of 99.9%.