Catalysts

A method of preparing a modified catalyst support is disclosed. The method comprises contacting a catalyst support material with a modifying component precursor in an impregnating liquid medium. The impregnating liquid medium comprises a mixture of water and an organic liquid solvent for the modifying component precursor, which mixture contains at least 2.5 % by volume water, but less than 12% by volume water based on the total volume of the impregnating liquid medium. The catalyst support material is selected from the group consisting of a catalyst support precursor which is convertible to a catalyst support upon calcination thereof and the catalyst support is in the form of a metal oxide which is an oxide of a metal selected from the group consisting of Al, Si, Ti, Mg, Zr and Zn; and a catalyst support selected from the group consisting of alumina in the form of one or more aluminium oxides, silica (SiO2), titania (TiO2), magnesia (MgO), zirconium oxide (ZrO2), zinc oxide (ZnO) and mixtures thereof. The modifying component precursor comprises a compound of a modifying component selected from the group consisting of Si, Zr, Ti, Cu, Zn, Mn, Ba, Ni, Al, V, W, La and mixtures of two or more thereof, thereby to obtain a modifying component containing catalyst support material. The method comprises optionally, calcining the modifying component containing catalyst support material at a temperature above 100°C to obtain a modified catalyst support. The method can further comprises preparing a modified catalyst support according to the above described method and introducing a precursor compound of an active catalyst component onto and/or into (i) the catalyst support material prior to contacting the catalyst support material with the modifying component precursor; (ii) the modifying component 30 containing catalyst support material; and/or (iii) the modified catalyst support thereby to obtain a catalyst precursor. A method of preparing a catalyst includes preparing a catalyst precursor using the above method of preparing a modified catalyst and reducing the catalyst precursor, thereby activating the catalyst precursor and obtaining the catalyst. A hydrocarbon synthesis process comprises preparing a catalyst using the above described method of preparing a catalyst and contacting hydrogen with carbon monoxide at a temperature above 100°C and a pressure of at least 10 bar with the catalyst so prepared, to produce hydrocarbons and, optionally, oxygenates of hydrocarb