Competitive Hydrogenation of Benzene in Reformate Gasoline over Ni Supported on SiO_2, SiO_2-Al_2O_3, and Al_2O_3 Catalysts: Influence of Support Nature

摘要

Nickel supported on SiO2, SiO2-Al2O3, and Al2O3 catalysts have been prepared and studied for the reduction of benzene in reformate gasoline. The sol gel method was used to prepare the catalysts. The evaluations were performed in a continuous fixed bed micro reactor fed by a flow of reformate gasoline at 398-473 K under atmospheric pressure. The physicochemical properties of the catalysts were obtained by XRD, FESEM, EDS-map, H-2-adsorption, and N-2 adsorption/desorption analysis to correlate the catalytic performances. To evaluate the performance of catalysts, different H-2/benzene molar ratios and space velocities were used. The Ni/SiO2-b, Ni/SiO2-c, and Ni/FDU12 catalysts decreased the benzene content to less than 1 vol % at 423 K. The high toluene conversion by Ni/MSA and Ni/Mil-53(Al) catalysts in comparison to other catalysts indicates that toluene hydrogenation is favored on these catalysts. The highest conversion of benzene in competitive hydrogenation was achieved at 423 K by the Ni/SiO2-c catalyst. In low H-2/benzene molar ratio and space velocity conditions, benzene molecules find a greater chance of hydrogenation. Due to selective hydrogenation by Ni/SiO2-c, the RON is slightly reduced.