A method for preparing a silica-modified catalyst support is described comprising: (i) applying an alkyl silicate solution to a porous support material in an amount to produce a silica content of the silica-modified catalyst support, expressed as Si, in the range 0.25 to 15% by weight, (ii) drying the resulting silicate-modified support and recovering a first alcoholic solution, (iii) optionally treating the dried silicate-modified support with water, drying the resulting water-treated support and recovering a second alcoholic solution, and (iv) calcining the dried material to form the silica-modified catalyst support, wherein the first alcoholic solution contains ≤10 vol % water and at least a portion of the first alcoholic solution is mixed with alkyl silicate to form the alkyl silicate solution.