Hydrogen production by partial oxidation of ethanol over Pt/CNT catalysts

Abstract

The platinum-supported catalysts have been prepared by ethylene glycol reduction method, and the catalysts were applied to the partial oxidation of ethanol (POE) for hydrogen production. Four types of support, including CNTs, Al2O3, ZrO2, and CeO2, were used on POE catalytic performance test. Prior to catalyst preparation, the influence of acidic pretreatment on CNTs purity, surface morphology, and pore structure were investigated. The acid-treated CNTs and prepared catalysts were characterized with N2 physisorption, Raman, thermogravimetric, and transmission electron microscopy analysis. The experimental results show that the particle size and metal dispersion of platinum on CNTs, as well as POE activity, depend on pH value of reducing agent and reduction temperature in the stage of catalyst preparation. In the condition pH value of 10 and temperature at 120 °C for catalyst 5 wt% Pt/CNTs preparation, 2 nm platinum clusters were obtained. Using the as-prepared catalyst to study the effects of POE reaction conditions on the ethanol conversion, hydrogen selectivity, and hydrogen production rate under constant gas hourly space velocity, the corresponding values at the optimum reaction temperature 400 °C and O2/C2H5OH molar ratio of 0.5 were 98.2%, 97.5%, and 202.3 mmol s−1 kg−1, respectively. Copyright © 2013 John Wiley & Sons, Ltd.