Ni(Co)-containing catalysts based on perovskite-like ferrites for steam reforming of ethanol

Abstract

Abstract 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.