Process for preparing a hydrotreating catalyst

Claim 1

PROCESS FOR PREPARING AN IMPROVED HYDROTREATING CATALYST COMPRISING: A. PRECIPITATING THE OXIDES OR HYDRATED OXIDES OF ALUMINUM AND SILICON FROM AN AQUEOUS SOLUTION OF WATER SOLUBLE SALTS THEREOF AT A TEMPERATURE RANGING FROM ABOUT 105* TO 120*F, AT A RANGE OF PH BETWEEN ABOUT 5 AND 9.5 AND AT AN ALUMINA CONCENTRATION, EXPRESSED AS AL2O3, BETWEEN ABOUT 1.2 TO 5.0 WEIGHT PERCENT, B. WASHING THE PRECIPITATE FROM STEP (A) TO REMOVE IMPURITIES THEREFROM, C. IMPREGNATING THE WASHED PRECIPITATE WITH GROUP VIII AND GROUP VI B METALS, D. DRYING THE IMPREGNATED CATALYST FROM STEP (C), E. ADDING SUFFICIENT WATER TO SAID DRIED IMPREGNATED CATALYST TO PROVIDE AN EXTRUDABLE SLURRY, F. EXTRUDING SAID SLURRY TO FORM AN EXTRUDATE, AND, G. DRYING AND CALCINING SAID EXTRUDATE WHEREBY AN IMPROVED HYDROTREATING CATALYST IS OBTAINED COMPRISING AN OXIDE OF A GROUP VIII METAL AND AN OXIDE OF A GROUP VI B METAL DEPOSITED UPON A SUPPORT MATERIAL CONSISTING ESSENTIALLY OF 1 TO 20 WEIGHT PERCENT SILICA AND THE BALANCE ALUMINA, SAID CATALYST BEING CHARACTERIZED BY EXHIBITING A SURFACE AREA OF AT LEAST ABOUT 190 M2/GM MEASURED IN MICROPORES HAVING A DIAMETER OF 30-80A AND PORE VOLUME LESS THAN ABOUT 0.10ML/GM. AS MACROPORES HAVING DIAMETERS GREATER THAN ABOUT 100 A.