Palladium–alumina composite membrane for hydrogen separator fabricated by combined sol–gel, and electroless plating technique

In this work, the performance of a novel coating of palladium over an alumina ceramic membrane was studied to enhance the hydrogen selectivity produced by an ethanol steam reforming reaction. Preparation of the palladium coated ceramic alumina membrane tube was performed using a combined sol–gel process and an electroless plating technique. Characterisation of the membrane was conducted using SEM and AFM. The palladium–alumina membrane was housed in the module membrane, and then packed with CuO–ZnO commercial catalyst to carry out the ethanol steam reforming reaction in a solid–gas phase. The reaction temperature and H2O/ C2H5OH feed molar ratio of the feed reactants were maintained at 573 K and 13:1, respectively. The reactions were then conducted at various reaction pressures in the range of 1.08–1.38 bar and WHSV of either 37 or 74 h−1. Their effects upon ethanol conversion, hydrogen recovery, hydrogen yield and hydrogen selectivity were investigated. At 1.38 bar with WHSV 37 h−1, the maximum of ethanol conversion (61.5%), hydrogen recovery (42.82%), hydrogen yield (26.75%) and hydrogen selectivity (92.6%) have been measured.