关键词: Raney镍, 固定床, 浸取过程, 加氢

Abstract: A novel activated fixed-bed Raney nickel catalyst was prepared by extruding Ni-Al alloy powder with 20% pseudo-boehmite as binding material. Appropriate leaching conditions of calcined alloy extrudates were studied by using of benzene hydrogenation activity as the main evaluation factor.Leaching procedures of such calcined alloy extrudates were also tested by contrast with alloy powder,in which released hydrogen and dissolved aluminum in caustic solution were determined.The experimental results showed that the fixed-bed Raney nickel catalyst could achieve higher benzene hydrogenation activity by leaching the alloy extrudates calcined at 860℃ for 2 h with 10%—20% NaOH solution at 80—90℃ for 3—4 h, and that the leaching procedures had significant effect on catalyst compressive strength. The metallic aluminum in calcined alloy extrudates could almost dissolve completely in caustic solution within 1—4 h, and microporous structures appeared on the surface of leached catalysts appear. The results of benzene hydrogenation suggested that the novel fixed-bed Raney nickel catalysts showed higher hydrogenation activity and stability, and that benzene could be hydrogenated to cyclohexane completely at mild conditions of reaction temperature 120 ℃, hydrogen pressure 0.5 MPa and space velocity 2 h^-1.

Key words: Raney镍, 固定床, 浸取过程, 加氢