A novel method for the synthesis of highly stable nickel-modified sulfated zirconia catalysts for n-pentane isomerization

摘要

AbstractA highly stable Ni modified sulfated zirconia catalyst was prepared by two different methods and used forn-pentane isomerization. The results showed that compared with the catalyst prepared by the sol-gel method, the catalyst prepared by the hydrothermal method showed higher surface area, larger pore size, smaller crystallite size of tetragonal ZrO2, more stable S-containing adsorbed species and a high isopentane yield. In particular, the Ni?/S2O82?-ZrO2–Al2O3, which was prepared by the hydrothermal method (Ni/SZA-R), provided a sustainable high isopentane yield (ca. 68%) with a slight deactivation (15%) only within 50h of continuous reaction. This result was ascribed to the catalyst's larger mean pore size and the increased concentration of more stable S-containing species formed compared to the catalyst prepared by the sol-gel method. The stability behavior of this Ni/SZA-R catalyst in terms of isopentane yield vs time appears by far larger (increase by a factor of ~ 2–15) compared to other non noble metal modified sulfated zirconia-based catalysts reported in the open literature.Graphical abstractDisplay OmittedHighlights?The hydrothermal method is beneficial to obtain large pore size.?The hydrothermal method is beneficial to obtain much smaller tetragonal ZrO2particles.?The carbon deposition largely suppressed by the large pore size.?The smaller tetragonal ZrO2particles are beneficial to stabilize more S species.?A highly stable non-noble-nickel modified catalyst can be obtained by hydrothermal method.]]>