GB762728A - Platinum-alumina catalyst containing added aluminum chloride - Google Patents

Abstract

Alumina-supported platinum catalysts are prepared by contacting alumina with an aqueous solution containing both aluminium chloride and an inorganic platinum-containing compound, and drying and reducing the product. The final catalyst preferably contains by weight 0.01-2 per cent of platinum and 0.1-15 per cent of aluminium chloride. Alumina derived from precipitated alumina trihydrate or monohydrate, or from aluminium chloride or acetate, may be used; it may be given a preliminary drying at 250 DEG -650 DEG F. for 2-24 hours. Minor amounts of silica. boria, or P2O5 may be present. Suitable platinum-containing compounds are chloroplatinic acid, platinum disulphide, ammonium chloroplatinate, and dinitrito-diammino-platinum. In examples, dried alumina is mixed to a paste with an aqueous solution of chloroplatinic acid and aluminium chloride. An alternative method of preparation is to add ammonia to mixed solutions of aluminium chloride and chloroplatinic acid in an amount insufficient to convert all the aluminium chloride to alumina. Reduction is effected by hydrogenation, calcination, or treatment with hydrazine or its salts. The catalyst is especially suitable for the hydroforming of naphthas, but is also useful for hydrogenation, hydrocracking, cracking and oxidation reactions.