Mechanistic Kinetic Modeling of Oxidative Steam Reforming of Bioethanol for Hydrogen Production over Rh–Ni/CeO2–ZrO2 Catalyst

Abstract

A kinetic study was carried out over Rh–Ni/CeO2–ZrO2 catalyst for the oxidative steam reforming of ethanol (OSRE). A Langmuir–Hinshelwood approach based on proposed surface reaction mechanisms was used to develop the kinetic models for the OSRE process. Oxidative steam reforming (OSRE), ethanol decomposition (ED), and water–gas shift (WGS) reactions were considered as the main reaction pathway to represent the overall OSRE process. Kinetic data were collected in a fixed bed reactor under the kinetic-control regime at three different temperatures. The kinetic parameters were estimated using a nonlinear regression method. The kinetic model was developed by considering dehydrogenation of adsorbed ethoxy species, decomposition of formate species, and decomposition of acetaldehyde as the rate-determining step for OSRE, WGS, and ED reactions, respectively. The developed model fitted well with the experimental observations at all studied temperatures and contact time. The activation energy for OSRE, WGS, and ED ...