Minimizing diphenylethane formation in alkylation of benzene by ethylene catalyzed by zeolite beta
AssigneeUop LLC
InventorGregory J. Gajda
Life of this patent
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Abstract
Reduction of the amount of 1,1-diphenylethane and heavier polyalkylated benzenes produced in the formation of ethylbenzene by alkylation of benzene with ethylene can be effected by treating a non-templated zeolite beta at thermal oxidation conditions. The precursor zeolite beta contains at least 0.5% carbon which represents a combination of coke and high molecular organic compounds which are not removed by an extended benzene wash at about 200-250.degree. C. The improvement leads to a product containing less than 0.3 weight percent 1,1-diphenylethane relative to ethylbenzene.
Claims9
A process for making ethylbenzene comprising alkylating in the liquid phase benzene with ethylene in a molar proportion ratio from 1 up to about 8 at a temperature from about 200.degree. C. up to about 260.degree. C. and at a pressure sufficient to maintain at least a partial liquid phase, in the presence of a site-modified zeolite beta catalyst, selected from the group consisting of (a) a site-modified beta resulting from heating at a temperature from about 450.degree. C. to about 750.degree. C. in the presence of a flowing oxygen-containing stream, a non-templated first zeolite beta having at least 0.5 wt. % carbon deposited thereon and (b) a site-modified zeolite beta resulting from calcining a zeolite beta at a temperature from about 675.degree. C. up to about 850.degree. C. in an atmosphere containing from about 5 up to about 25 wt. % water, and has a silica alumina ratio no more than about 30.
A process for preparing a monoalkylated benzene comprising alkylating in the liquid phase benzene with an olefin in a molar proportion ratio from 1 up to about 15 at a temperature from about 100.degree. C. up to about 425.degree. C. and at a pressure sufficient to maintain at least a partial liquid phase, in the presence of a site-modified zeolite beta catalyst, selected from the group consisting of (a) a site-modified beta resulting from heating at a temperature from about 450.degree. C. to about 750.degree. C. in the presence of a flowing oxygen-containing stream, a non-templated first zeolite beta having at least 0.5 wt. % carbon deposited thereon and (b) a site-modified zeolite beta resulting from calcining a zeolite beta at a temperature from about 675.degree. C. up to about 850.degree. C. in an atmosphere containing from about 5 up to about 25 wt. % water, and has a silica:alumina ratio no more than about 30.
Dependencies are inferred from the claim text.