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US3997618A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for isomerizing alkyl benzenes

Assignee: Engelhard Minerals and Chemicals Corp
•
Filing: 1975-05-23
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Granted: 1976-12-14
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Expires: 1995-05-23
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Abstract

Abstract There is disclosed a process for isomerizing alkylated benzenes having from 3-10 carbon atoms and methyl or ethyl alkyl substituents. The reaction is conducted in the presence of molecular hydrogen and a catalyst having a platinum group metal, especially platinum, and rhenium promoters on a porous, solid oxide, acidic support. The support can be a mixture of a low acidic material such as alumina, and a higher acidic material such as silica-alumina or crystalline aluminosilicate. The catalyst promoters are preferably supported on the low acidity base component.

Inventors

  • 👤 Kurt W. Cornely
  • 👤 Saul G. Hindin
  • 👤 Carl D. Keith

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 03:39
CPC Classifications
C; C07; C07C; C07C5/00; C07C5/22; C07C5/27; C07C5/2729; C07C5/2732; C07C5/2754

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 188 words
A process for isomerizing alkylated benzene hydrocarbons of 8 to 10 carbon atoms wherein the alkyl substituents are selected from the group consisting of methyl and ethyl groups, which comprises isomerizing such alkylated benzene hydrocarbons in the presence of molecular hydrogen under isomerization conditions including a temperature of about 650° to 950° F and in contact with a catalyst, said catalyst consisting essentially of a physical admixture of a. minor amounts each of platinum group metal and rhenium supported on a major amount of a porous, solid metal oxide base, said base having a surface area of at leastabout 100 square meters per gram and having a tertiary butylbenzene dealkylation activity at 455° C (without water addition) of up to about 15 cubic centimeters (STP) per gram per minute; and b. 0.5 to 95% of a high acidity oxide component consisting essentially of a porous, solid metal oxide having a surface area of at least about 100 square meters per gram and having a tertiary butylbenzene dealkylation activity of at least about 500, wherein the physical admixture has a tertiary butylbenzene dealkylation activity of about 400 to 1200.
Claim 2
Dependent Claim 188 words
A process for isomerizing alkylated benzene hydrocarbons of 8 to 10 carbon atoms wherein the alkyl substituents are selected from the group consisting of methyl and ethyl groups, which comprises isomerizing such alkylated benzene hydrocarbons in the presence of molecular hydrogen under isomerization conditions including a temperature of about 650° to 950° F and in contact with a catalyst, said catalyst consisting essentially of a physical admixture of a. minor amounts each of platinum group metal and rhenium supported on a major amount of a porous, solid metal oxide base, said base having a surface area of at leastabout 100 square meters per gram and having a tertiary butylbenzene dealkylation activity at 455° C (without water addition) of up to about 15 cubic centimeters (STP) per gram per minute; and b. 0.5 to 95% of a high acidity oxide component consisting essentially of a porous, solid metal oxide having a surface area of at least about 100 square meters per gram and having a tertiary butylbenzene dealkylation activity of at least about 500, wherein the physical admixture has a tertiary butylbenzene dealkylation activity of about 400 to 1200.
Claim 3
Dependent Claim 14 words
The process of claim 1 in which the platinum group is metal is platinum.
Claim 4
Dependent Claim 26 words
The process of claim 1 in which the base of relatively low activity is alumina and the metal oxide of relatively high activity is amorphous silica-alumina.
Claim 5
Dependent Claim 28 words
The process of claim 1 in which the platinum group metal is platinum and each of the platinum and rhenium is about 0.2 to 1% of the catalyst.
Claim 6
Dependent Claim 50 words
The process of claim 1 in which the relatively low activity base is alumina, and the metal oxide of relatively high activity is crystalline aluminosilicate having a silica-to-alumina mole ratio of about 2 to 6:1, pore openings of 10 to 15 A diameter and a sodium content below about 1%.
Claim 7
Dependent Claim 13 words
The process of claim 5 in which the platinum group metal is platinum.
Claim 8
Dependent Claim 25 words
The process of claim 2 in which the alkylated benzene feed is a xylene mixture containing meta-xylene and less than an equilibrium amount of para-xylene.
Claim 9
Dependent Claim 25 words
The process of claim 4 in which the alkylated benzene feed is a xylene mixture containing meta-xylene and less than an equilibrium amount of para-xylene.
Claim 10
Dependent Claim 22 words
The process of claim 7 in which the isomerization conditions include about 700° to 900° F. and about 100 to 350 psig.
Claim 11
Dependent Claim 22 words
The process of claim 8 in which the isomerization conditions include about 700° to 900° F. and about 50 to 500 psig.
Claim 12
Dependent Claim 23 words
The process of claim 9 in which the alumina of the catalyst is made by calcination of a hydrous alumina predominating in trihydrate.
Claim 13
Dependent Claim 23 words
The process of claim 10 in which the alumina of the catalyst is made by calcination of a hydrous alumina predominating in trihydrate.

References Cited (Backward Citations)

US3632835A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-12-14 1980-06-14 1980-12-14 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-12-14 1984-06-14 1984-12-14 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-12-14 1988-06-14 1988-12-14 $7700.00 Window Closed / Lapsed

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