process for the production of spherical siliciumdioxidteilchen with high water resistance and high strength and utilization by this procedure produced particles as support material for catalysts

摘要

1525386 Epoxidation SHELL INTERNATIONALE RESEARCH MAATSCHAPPIJ BV 4 Nov 1975 [6 Nov 1974] 47991/74 Heading C2C [Also in Division C1] Epoxidation of propylene or alkyl chloride with an organic hydroperoxide is carried out by contracting the reactants in the liquid phase, preferably at elevated temperature and pressure in the presence of a catalyst comprising at least one metal selected from the group Mo, W, Ti, Zr and V, supported on globular silica particles having high water resistance and bulk crushing strength (as defined) which are made by:- (a) mixing an aqueous alkali metal silicate with an aqueous acid; (b) converting the hydrosol into droplets; (c) gelling the droplets in a liquid immiscible with water; (d) removing at least 25% of the water from the hydrogel by evaporation ; (e) decreasing the alkali metal content of the particles in an aqueous medium to less than 1 wt. per cent and (f) drying and calcining.