Active ruthenium phosphide as selective sulfur removal catalyst of gasoline model compounds

Abstract

This paper presents the catalytic activity of ruthenium phosphides supported on SBA-15 material as hydrodesulfurization (HDS) catalysts of gasoline model compounds. It was studied the influence of the P/Ru molar ratio of 0.5, 1, 2, 3, and 4.5 (samples were labeled as 0.5-P/Ru, 1-P/Ru, 2-P/Ru, 3-P/Ru and 4.5-P/Ru) in the hydrodesulfurization of 3-methyl-thiophene as a model molecule and evaluated under mild reaction conditions. The ruthenium phosphide phase was synthesized from a conventional phosphate reduction method using RuCl3 and (NH4)2HPO4 as precursors. The catalysts were characterized by XRPD, N2 adsorption–desorption isotherms, TEM, EDS, XPS, NH3-TPD, H2-TPD and CO chemisorption. All catalysts maintained the mesoporous structure characteristic of the SBA-15 support, although pore blockage occurred at high P loadings. TEM images and EDS mapping showed well dispersed active phosphide phases, mainly RuP and Ru2P, as evidenced by XRPD. 3-P/Ru catalyst became to be the most active in the HDS reaction, with a high isomerization ability, which was assigned to its medium acidity and higher amount of active species on the surface that activates H2 species.