Effects of Fe species on promoting the dibenzothiophene hydrodesulfurization over the Pt/γ-Al2O3 catalysts

The improvement of the sulfur tolerance over Pt catalyst is critical for the hydrotreatment of crude oil. Fe was co‒impregnation with Pt on γ-Al 2 O 3 at different calcination temperature. Results revealed that adding Fe significantly facilitated the reduction of Pt oxides for the catalyst calcined at 400 °C. The morphological analysis and CO chemisorption showed Fe improved the dispersion of Pt nanoparticles. The surface chemical state analysis implied the co‒existence of the electron‒deficient Pt and metallic Fe. However, the increase of calcination temperature caused a decreased reducibility of Pt oxides due to strong metal support interaction. A higher dibenzothiophene hydrodesulfurization conversion of 97.7 % with a dominant biphenyl selectivity of 96.7 % were acquired for the catalysts incorporated with Fe. The density functional theory calculations confirmed the alloyed Fe led to the formation of electron‒deficient Pt atoms, and the higher affinity to sulfur made Fe be a favorable additive for noble metal catalyst in the hydrodesulfurization.