GB1276428A - A process for epoxidizing olefins with hydroperoxides - Google Patents

Abstract

1276428 Boron containing catalysts SHELL INTERNATIONALE RESEARCH MAATSCHAPPIJ NV 20 Oct 1970 [22 Oct 1969] 49766/70 Heading B1E [Also in Division C2] Title compositions, used in the epoxidation of olefines, comprise boron, preferably trivalent B, in chemical combination with silica or silicates. Compositions contain at least 0.1%, preferably 0.2-25% B or B 2 O 3 , and the silica or silicates contain at least 50%, preferably at least 75%, Si as SiO 2 and have a specific surface area of at least 1 m<SP>2</SP>/g, preferably 25-800 m<SP>2</SP>/g. Suitable siliceous solids are synthetic, porous silica in a relatively dense, close packed form, consisting of particles of amorphous silica flocculated or linked together, including silica gel and precipitated silica, synthetic silica powders consisting of particles of amorphous silica flocculated in openpacked, readily disintegrated, loosely knit aggregates, especially fumed pyrogenic silica, crystalline alumino-silicates (molecular sieves); crystalline mineral silicates; clay minerals and micaceous materials. The composition may also contain promoters especially oxides of Mg.Ca, Sr and Ba or compounds easily converted into the oxides. Amounts up to 5% promoter are required. The catalyst is prepared by conventional means and may be subjected to pretreatment, e.g. heating in a non reducing gas at 350-800‹C for 1-18 hrs. The compositions may be employed as powders, flakes, spheres or pellets. In the use of the composition to catalyse the epoxidation reaction up to 10% oxides or hydroxides of Sn, Nb, Ta, Cr, Mo, W, Re, U, Bi and rare earth elements of atomic Nos. 57-71 inclusive, may be included.