Kinetic studies of the partial oxidation of gasoline (POXG) over a Ni-CeO2 catalyst in a fixed-bed flow reactor

摘要

The kinetics of the partial oxidation (POX) reforming of gasoline was studied over a Ni-CeO2 catalyst as a function of gasoline and oxygen molar flow rates as well as reaction temperature in a tubular fixed-bed reactor. The kinetic experimental runs were conducted at atmospheric pressure, a temperature range of 673-1023 K, gas hourly space velocity (GHSV) in the range of 160,000 and 940,000 h(-1), and oxygen/carbon ratio in the range of 0.25-1.0. The reaction mechanisms were developed and modeled using the Langmuir-Hinshelwood-Hougen-Watson (LHHW) and Eley-Rideal (ER) formulations. Out of the 18 models developed and tested one model based on the LHHW formulation was adopted after evaluating the average absolute deviation and activation energy values and compared to values obtained with the empirical power law model. The best model to describe the reforming process under the given conditions was a dual-site LHHW model involving the dissociative adsorption of gasoline (C8.27H15.10) and oxygen (O-2) followed by bimolecular surface reaction as the rate-determining step. (C) 2007 Elsevier Ltd. All rights reserved.