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Indexed by:Journal Papers

Date of Publication:2015-12-31

Journal:JOURNAL OF PHYSICAL CHEMISTRY C

Included Journals:SCIE、EI、Scopus

Volume:119

Issue:52

Page Number:29052-29061

ISSN No.:1932-7447

Abstract:Development of highly active and sulfur-tolerant catalysts for deep hydrodesulfurization (HDS) is of great importance in petroleum refining. Here, the discovery of Fe-substituted Ni Si intermetallic catalysts (Ni1-x,FexSi2) that efficiently removes dibenzothiophene (DBT) by HDS is reported. The structure of the catalyst was identified through X-ray diffraction, Mossbauer spectroscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. The results showed that Fe atoms substituted Ni atoms in Nii_xFe Si, catalysts, which preferentially bond with Ni to form alloy and combine with Si to form silicide. The DBT activity for the Ni1-xFexSi2 has the following order: Ni0.75Fe0.25Si2 > NiSi2 > N10.50Fe0.50Si2 Ni0.25Fe0.75Si2 i Fe Si. The positive synergistic effect on HDS activity can be correlated to that the formation of Ni Fe and Fe Si bonds makes the metal site to have high d-electron density, which promotes the hydrogenation activity. Comparison with the fresh and spent catalysts revealed the stability and sulfur resistance of these catalysts. The present findings suggest that Fe-substituted Ni Si intermetallics catalysts provide a good starting point for a new catalyst development in the HDS field.