| Ruthenium-zinc catalyst was very efficient for the selective hydrogenation of benzene to cyclohexene in a liquid phase. Owing to a large amount of this kind of catalyst and high contents of noble metals in it, it was of great significance to study the recovery of ruthenium from the spent catalyst. In this study, a recovery method was proposed, and the related process conditions optimized through experiments. were as follows: 1) Roasting at 650 ℃ for 4 h, ball milling to 80 mesh, 2) alkali melting at 650 ℃ for 5 h with sodium hydroxide and potassium permanganate (1:2:0.5 mass ratio, 3) distilling ruthenium 2 h at 95 ℃ using chlorine gas. Under these optimal conditions, the direct yield of ruthenium was 97.66%, and the quality of ruthenium trichloride conformed to the standard. |
