Method for preparing cracking catalyst involving a mild acid and steam treatment

Claim 1

IN A PROCESS FOR MANUFACTURING A SILICEOUS CRACKING CATALYST BY THE FORMATION OF A SILICEOUS HYDROSOL AND GELATION OF SAID HYDROSOL TO A HYDROGEL, THE IMPROVEMENT WHICH COMPRISES SUBJECTING THE SILICEOUS HYDROGEL, SUBSTANTIALLY FREE OR ALKALI METAL, TO TREATMENT WITH A DILUTE ACID SOLUTION OF LESS THAN ABOUT 5 PERCENT BY WEIGHT CONCENTRATION FOR A PERIOD OF AT LEAST ABOUT 10 HOURS BUT NOT EXCEEDING ABOUT 200 HOURS AT A TEMPERATURE BETWEEN ABOUT 60* F. AND THE NORMAL BOILING POINT OF SAID ACID SOLUTION, UNDER CONDITIONS SUCH THAT SUBSTANTIALLY NO DISSOLUTION OF THE HYDROGEL IS ENCOUNTERED, WASHING WATER-SOLUBLE MATERIAL FROM THE ACID-TREATED HYDROGEL AND THEREAFTER SUBJECTING THE WASHED HYDROGEL TO TREATMENT WITH STEAM AT A TEMPERATURE IN THE RANGE OF ABOUT 800* F. TO ABOUT 1500* F. FOR AT LEAST ABOUT 2 HOURS.