Enhanced Fe–Cr dispersion on mesoporous silica support using surfactant-assisted melt-infiltration for the water-gas shift reaction in waste-to-hydrogen processes

Abstract

Iron-chromium/SBA-15 (Fe–Cr/SBA-15) catalysts for high-temperature water-gas shift reactions (HTS) were prepared using the surfactant-assisted melt-infiltration (SAMI) method. The SAMI method was used to synthesize an efficient catalyst that could simultaneously achieve high dispersion and loading (Fe: 40 wt% and Cr/Fe molar ratio: 0.25) without a liquid solution. According to X-ray diffraction (XRD) and transmission electron microscopy analyses, it was observed that the Span60 surfactant enhanced Fe3O4 particle dispersion. N2 adsorption-desorption analysis indicated that the Fe3O4 and chromium oxide particles were thoroughly infiltrated inside the mesopores of the SBA-15 support. XRD and temperature-programmed-reduction analyses revealed that the well-dispersed Fe3O4 acted as active sites for the HTS reaction when Span60 was added to the Fe–Cr catalyst. In other words, the Fe–Cr catalyst synthesized via SAMI exhibited better performance and stability for the HTS reaction than that prepared without the surfactant.