For two series of catalysts based on praseodymium ferrite, their structural and redox properties as well as performance in ethanol steam reforming have been studied. The first series was PrFe1-xNi(Co)xO3 (x=0.3-0.4) perovskites prepared by modified Pechini route, and the second one was 5%wt.Ni(Co)/PrFeO3 of different dispersion prepared by impregnation of PrFeO3, including samples modified by 5%wt. Mo. At temperatures above 700°C, for all catalysts, the main products were hydrogen and CO. At temperatures below 700°C, initial ethanol conversion and hydrogen yield were higher for supported catalysts as compared with ones derived from Ni(Co)-containing perovskites. While Ni-based catalysts derived from perovskite were more active as compared with Co-based samples, Co-supported PrFeO3 perovskite has shown a higher initial activity as compared with Ni-supported one. The long-term tests in the realistic feed and TEM studies of spent catalysts revealed that perovskite-derived catalysts have a higher coking stability than perovskite-supported ones due to formation of highly dispersed Ni-Fe alloy particles strongly interacting with disordered perovskite–like matrix. The method of Mo supporting only slightly affects the initial activity of Ni/PrFeO3–based catalysts but noticeably modifies their coking stability: 5%Mo/5%Ni/PrFeO3 catalyst prepared by successive impregnation possesses the highest stability among perovskite-supported catalysts.
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