Kinetic studies of the partial oxidation of isooctane for hydrogen production over a nickel-alumina catalyst

The kinetics of the catalytic partial oxidation of isooctane for hydrogen (H-2) production over a stable Ni/gamma-Al2O3 catalyst was investigated at atmospheric pressure in the temperature range of 863-913 K, ratio of weight of catalyst to the molar feed rate of isooctane (W/F-iC8(o)) in the range of 7.09-30.89 kg mol(-1), and molar feed ratio O-2/i-C8H18 of 4.0 in a 12.7 mm diameter Inconel micro-reactor housed in an electrically controlled furnace. The developed rate models were based on the Langmuir-Hinshelwood-Hougen-Watson (LHHW) and Eley-Rideal (ER) formulations. Out of the 18 models developed, 10 were eliminated due to poor predictive efficiency. A LHHW mechanism requiring the dissociative adsorption of isooctane and molecular adsorption of oxygen on a single site was the most likely pathway for the partial oxidation of isooctane. The reaction order of 1.5 indicates a strong coverage of nickel by isooctane. (c) 2006 Elsevier Ltd. All rights reserved.