Patent US3974061A successfully refreshed from Google Patents.
US3974061A
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Isomerization of C5 and C6 isomerizable hydrocarbons
Assignee: Texaco Inc
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Filing: 1974-12-16
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Granted: 1976-08-10
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Expires: 1994-12-16
Abstract
Abstract An improved vapor phase catalytic isomerization of a hydrocarbon fraction containing C 5 and C 6 isomerizable hydrocarbons is obtained by subjecting the hydrocarbon fraction in the presence of gaseous hydrogen to a plural stage, such as a dual stage, catalytic isomerization operation preferably employing a chlorinated platinum-containing alumina catalyst wherein the hydrocarbon fraction undergoing isomerization is supplied sequentially and serially from the first stage through to the last stage of the plural stage isomerization operation and wherein the first stage of the plural stage isomerization operation is supplied with the hydrocarbon fraction at a temperature in the range about 300°-305°F. and recovered from the first stage at a temperature in the range about 310°-335°F. The last stage of the plural stage isomerization operation is supplied with the hydrocarbon fraction at a temperature in the range about 315°-350°F. and recovered from the last stage at a temperature in the range about 340°-370°F. In the plural stage isomerization operation the catalyst employed in the first stage is active and fresh whereas the catalyst employed in the last stage is relatively inactive or depleted.
Inventors
- 👤 Robert E. Quisenberry
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 17:11
CPC Classifications
C; C10; C10G; C10G45/00; C10G45/02; C10G45/04; C10G2400/00; C10G2400/02
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
269 words
A process for isomerizing a hydrocarbon fraction having a boiling point range in the range from about 90° to about 210°F. and containing C 5 and C 6 isomerizable hydrocarbons which comprises subjecting said hydrocarbon fraction to a plural stage vapor phase catalytic isomerization operation, wherein the catalyst employed in each stage of said plural stage catalytic isomerization operation is chlorinated platinum-containing alumina catalyst, wherein the activity of the catalyst employed in the first stage of said plural stage isomerization operation is greater than the activity of the catalyst employed in the final stage of said plural stage isomerization operation, wherein said catalyst employed in said first stage is fresh or regenerated catalyst to obtain maximum 2,2-dimethylbutane and isopentane yields, wherein said catalyst in said final stage, after service as a first stage catalyst, is employed to obtain in said final stage maximum methylcyclopentane yield, the first stage of said isomerization operation being carried out under conditions such that the hydrocarbon fraction is supplied to said first stage at a temperature in the range about 300°-305°F. and recovered from said first stage at a temperature in the range 310°-335°F. and wherein the hydrocarbon fraction undergoing plural stage isomerization is supplied to the last stage of said plural stage isomerization operation at a temperature in the range about 315°-350°F. and recovered from said last stage at a temperature in the range about 340°-370°F., in the aforesaid vapor phase catalytic isomerization operation the hydrocarbon fraction undergoing isomerization being supplied sequentially and serially from the first stage of the plural stage isomerization operation through to the last stage of said isomerization operation.
Claim 2
Dependent Claim
269 words
A process for isomerizing a hydrocarbon fraction having a boiling point range in the range from about 90° to about 210°F. and containing C 5 and C 6 isomerizable hydrocarbons which comprises subjecting said hydrocarbon fraction to a plural stage vapor phase catalytic isomerization operation, wherein the catalyst employed in each stage of said plural stage catalytic isomerization operation is chlorinated platinum-containing alumina catalyst, wherein the activity of the catalyst employed in the first stage of said plural stage isomerization operation is greater than the activity of the catalyst employed in the final stage of said plural stage isomerization operation, wherein said catalyst employed in said first stage is fresh or regenerated catalyst to obtain maximum 2,2-dimethylbutane and isopentane yields, wherein said catalyst in said final stage, after service as a first stage catalyst, is employed to obtain in said final stage maximum methylcyclopentane yield, the first stage of said isomerization operation being carried out under conditions such that the hydrocarbon fraction is supplied to said first stage at a temperature in the range about 300°-305°F. and recovered from said first stage at a temperature in the range 310°-335°F. and wherein the hydrocarbon fraction undergoing plural stage isomerization is supplied to the last stage of said plural stage isomerization operation at a temperature in the range about 315°-350°F. and recovered from said last stage at a temperature in the range about 340°-370°F., in the aforesaid vapor phase catalytic isomerization operation the hydrocarbon fraction undergoing isomerization being supplied sequentially and serially from the first stage of the plural stage isomerization operation through to the last stage of said isomerization operation.
Claim 3
Dependent Claim
21 words
A process in accordance with claim 1 wherein said hydrocarbon fraction contains a minor amount by weight of n-pentane and n-hexane.
Claim 4
Dependent Claim
32 words
A process in accordance with claim 1 wherein each of the stages of said plural stage vapor phase catalytic isomerization operation is carried out at a pressure in the range 450-550 psig.
Claim 5
Dependent Claim
30 words
A process in accordance with claim 1 wherein each of the stages of said plural stage vapor phase catalytic isomerization operation is carried out in the presence of gaseous hydrogen.
Claim 6
Dependent Claim
17 words
A process in accordance with claim 4 wherein the hydrogen to hydrocarbon mol ratio is about 1.25.
Claim 7
Dependent Claim
45 words
A process in accordance with claim 1 wherein the temperature differential between the temperature of the hydrocarbon fraction supplied to said first stage and the temperature of the hydrocarbon fraction supplied to said last stage is in the range from about 10° to about 50°F.
Claim 8
Dependent Claim
45 words
A process in accordance with claim 1 wherein the temperature differential between the temperature of the hydrocarbon fraction recovered from said first stage and the temperature of the hydrocarbon fraction recovered from the last stage is in the range from about 5° to about 60°F.
Claim 9
Dependent Claim
19 words
A process in accordance with claim 1 wherein said plural stage isomerization operation is a two stage isomerization operation.
Claim 10
Dependent Claim
55 words
A process in accordance with claim 1 wherein upon depletion of the activity of the catalyst employed in said last stage said last stage is removed from said isomerization operation, the immediately preceding stage of the isomerization operation becomes the last stage and a new stage containing fresh catalyst is employed as said first stage.
Claim 11
Dependent Claim
19 words
A process in accordance with claim 1 wherein each of the stages of said isomerization operation is operated adiabatically.
Claim 12
Dependent Claim
19 words
A process in accordance with claim 1 wherein said plural stage isomerization operation is a substantially isobaric isomerization operation.
Claim 13
Dependent Claim
22 words
A process in accordance with claim 1 wherein the stages making up said plural stage isomerization operation number in the range 2-4.
Claim 14
Dependent Claim
38 words
A process in accordance with claim 1 wherein each of the stages of said plural stage isomerization operation is supplied with the hydrocarbon fraction undergoing isomerization at a liquid hourly space velocity in the range of about 1-2.
Claim 15
Dependent Claim
25 words
A process in accordance with claim 1 wherein said hydrocarbon fraction contains n-pentane and n-hexane in an amount in the range about 15-25% by weight.
Claim 16
Dependent Claim
20 words
A process in accordance with claim 1 wherein said hydrocarbon fraction contains about 8-15% by weight benzene, cyclohexane and methylcyclopentane.
Claim 17
Dependent Claim
28 words
A process in accordance with claim 1 wherein the catalyst employed in each of the stages of said plural stage isomerization operation is an in-situ chlorinated platinum-eta-alumina catalyst.
Claim 18
Dependent Claim
19 words
A process in accordance with claim 1 wherein said catalyst has a platinum content of about 0.6% by weight.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-08-10 | 1980-02-09 | 1980-08-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-08-10 | 1984-02-09 | 1984-08-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-08-10 | 1988-02-09 | 1988-08-10 | $7700.00 | Window Closed / Lapsed |