Dealumination of aluminosilicates
AssigneeArco Chemical Technology, L.P.
InventorsRobert J. Saxton, Guy L. Crocco, John G. Zajacek
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Abstract
Crystalline aluminosilicates such as zeolite beta may be readily dealuminated using organic sulfonic acids such as methanesulfonic acid to provide useful catalysts or catalyst precursors. A high degree of aluminum removal with minimal loss of crystallinity is possible even when an organic template is not present in the starting aluminosilicate.
Claims15
A method of removing framework aluminum from a zeolite beta, said method comprising contacting the zeolite beta with a water-soluble organic sulfonic acid, wherein the water-soluble organic sulfonic acid is present at a concentration of at least 2N in an aqueous medium, at a temperature of from 20.degree. C. to 200.degree. C. to form a dealuminated zeolite beta having a framework Si/Al ratio of at least 800 and a crystallinity of at least 90% relative to the crystallinity of the zeolite beta prior to said acid treatment.
A method of removing framework aluminum from a zeolite beta, said method comprising contacting the zeolite beta with a water-soluble organic sulfonic acid having the structure RSO.sub.3 H wherein R is C.sub.1 -C.sub.20 alkyl or C.sub.6 -C.sub.20 aryl, wherein the water soluble organic sulfonic acid is present at a concentration of at least 5N in an aqueous medium, at a temperature of 40.degree. C. to 120.degree. C. to form a dealuminated zeolite beta having a framework Si/Al ratio of at least 800 and a crystallinity of at least 90% relative to the crystallinity of the zeolite beta prior to said acid treatment.
Dependencies are inferred from the claim text.