CASE 4395 ABSTRACT OF THE INVENTION "AMORPHOUS SILICA-BASED CATALYST AND PROCESS FOR ITS PRODUCTION" This invention relates to a catalyst for the conversion ofsynthesis gas or methanol to hydrocarbons and to a process for itsproduction. The catalyst comprises a highly porous amorphous silica havinga monolayer of an amphoteric metal chemically bonded onto up to 90%of the surface area of the silica matrix. The catalyst has a maximumpore diameter of 1.5 nm and the metal is preferably aluminium. Thecatalyst is produced by treating the silica with a solution of ahydrolysable aluminium compound, removing the solvent and causing thesilica surface to hydrolyse the compound, thus chemically bonding thealuminium onto the surface of the silica matrix. Optionally, thecatalyst is mixed intimately with a Fischer-Tropsch catalyst to enablethe direct conversion of synthesis gas to hydrocarbons. The catalyst will be of use in the conversion of synthesis gasor methanol to higher hydrocarbons.