WGS and CO - PrOx reactions using gold promoted copper - ceria catalysts : “ bulk CuO - CeO 2 vs . CuO - CeO 2 / Al 2 O 3 with low mixed oxide content ”
نویسندگان
چکیده
A copper-ceria bulk catalyst has been compared to a series of catalysts designed according to the as called “supported approach”, corresponding to the dispersion of low content mixed copper-ceria oxide on alumina matrix. The principal characteristics of both types of catalysts are contemplated and the differences in their electronic and redox properties discussed in details. As a plus, the gold metal promotion of the catalysts is also envisaged. The advantages of the systems in the CO clean up reactions, WGS and CO-PrOx are commented. While the WGS activity appears to be ruled especially by the Cu/Ce surface to volume ratio, the CO-PrOx reaction is governed by the CuO loading. Gold addition provides benefits only at the low temperature WGS regime. Very importantly, the supported systems are always superior to the bulk configuration in terms of specific activity, a key factor from the catalyst’s design perspective. 1 Corresponding author present address: Department of Chemical and Process Engineering, University of Surrey Guildford, GU2 7XH, United Kingdom.
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تاریخ انتشار 2016