Patent ID: 6872685

Claim:
Method for preparing a highly homogeneous amorphous silica-alumina cogel catalyst comprising: vigorously mixing an aqueous silicate solution with an aqueous solution of an acid aluminum salt while maintaining the pH of the mixed solution less than 3.0 and ensuring vigorous and complete mixing of the aluminum salt and silicate solutions to form an acidified silica sol in the aluminum salt solution; gradually adding a basic precipitant to said acidified silica sol in the aluminum salt solution while vigorously mixing the solution to raise the pH of the solution to greater than 3.0, producing a cogel slurry; continuing the addition of basic precipitant to a final PH in the range of 5-9 while vigorously mixing the cogel slurry to maintain a uniform pH throughout the cogel slurry washing the precipitated cogel; and processing the precipitated cogel into a finished catalyst.