Renewable hydrogen production from oxidative steam reforming of bio-butanol over CoIr/CeZrO2 catalysts: Relationship between catalytic behaviour and catalyst structure

摘要

Several bimetallic CoIr/Ce_(0.82)Zr_(0.18)O2 catalysts with supports of different characteristics were studied in the oxidative steam reforming of a bio-butanol raw mixture (n-butanol/acetone/ethanol = 6/3/1, mass ratio). Ce_(0.82)Zr_(0.18)O2 supports were prepared by precipitation and then calcination at different temperatures (500°C, 700°C and 900°C). The calcination temperature of the support determined certain characteristics of the final catalyst, namely: BET surface area, crystallite size, basicity, reduction properties and oxygen storage capacity (OSC). All of these factors were found to affect the performance of the catalysts in terms of: raw mixture conversion, hydrogen selectivity and resistance to deactivation upon long-term testing. Several techniques such as XRD, TPR, CO2 TPD, CO2 adsorption calorimetry, Raman, DRIFT, TEM, XPS and OSC were used to characterize the catalysts. Characterization of samples before and after catalytic tests allowed us to determine the influence of the catalyst characteristics on the deactivation process.