Preparation of nano-Ru/[Bmim][BF4] catalyst and its application in the benzene selective hydrogenation

The nano-Ru/[Bmim][BF4] catalyst was prepared for benzene selective hydrogenation in 1-n-butyl-3- methylimidazolium tetrafluoroborate [Bmim][BF4] by chemical reduction method. TEM analysis of these nanoparticles sho wed the monodisperse Ru-0 particles which were prepared by positive dropping method dispersed in the ionic liquids with diameters less than 5nm. The Ru-0 particles which were prepared by reverse dropping method agglomerated with diameters more than 10nm. KBH4 was the suitable reductant. The optimum loading of Ru was 1.5%. The hydrogenation activity of Ru/ [Bmim] [BF4] was high and the selectivity of cyclohexene was very low. Selectivity of cyclohexene was only 14.5% at 27.3 % benzene conversion.