US3850744A
Expired / Lapsed
US
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Method for utilizing a fixed catalyst bed in separate hydrogenation processes
Assignee: Gulf Research and Development Co
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Filing: 1973-02-27
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Granted: 1974-11-26
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Expires: 1993-02-27
Abstract
Abstract Middle distillate virgin oils, such as straight run furnace oil, jet fuel or kerosene are required to meet many commercial specifications, among which are maximum allowable total sulfur content, maximum allowable mercaptan sulfur content and maximum allowable total acid number. Middle distillates which do not meet commercial specifications in regard to total sulfur content can be hydrodesulfurized for the removal of the portion of the total sulfur required for meeting the commercial requirement. Such hydrodesulfurization requires more severe conditions than do processes for reduction of total acid number or for reduction of mercaptan sulfur content so that under the severe conditions required for hydrodesulfurization, excessive total acid number and excessive mercaptan content are automatically concomitantly reduced to commercially acceptable levels. The present invention relates to the hydrotreatment of virgin middle distillates which meet commercial specifications in regard to total sulfur content in the absence of prior hydrotreating or any other treatment, but do not meet commercial specifications in regard to total acid number or in regard to mercaptan sulfur content. According to the present invention, the latter middle distillates are not blended with high total sulfur feeds flowing to hydrodesulfurization processes requiring severe conditions to accomplish reduction in total sulfur content, but are hydrotreated separately under relatively more mild catalytic hydrotreating conditions to reduce mercaptan sulfur content or total acid number at hydrotreating severities which are so mild that there is an extremely limited consumption of hydrogen and a very limited removal of total sulfur. The catalyst employed in the mild hydrotreating processes of this invention is a deactivated hydrotreating catalyst from a more severe hydrodesulfurization or other hydrotreating operation which is no longer of viable use in the more severe operation due to numerous cycles of use and regeneration, due to excessive metals deposit thereon, or any other reason.
Inventors
- 👤 J Strom
- 👤 R Plundo
- 👤 T Readal
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 21:51
CPC Classifications
C; C10; C10G; C10G65/00; C10G65/14; C10G65/16; C10G45/00; C10G45/02
Claims Analysis
Total Claims: 29
Claim 1
Independent Claim
139 words
A RELATIVELY LOW PRESSURE HYDROTREATING PROCESS PERFORMED IN A FIRST AND RELATIVELY LOW PRESSURE RECTOR, COMPRISING PASSING A FIRST FEED OIL COMPRISING MIDDLE DISTILLATE STRAIGHT RUN FEED OIL AND HYDROGEN DOWNWARDLY OVER A HYDRODESULFURIZATION CATALYST THAT HAS BEEN DEACTIVATED IN A PRIOR RELATIVELY HIGH PRESSURE HYDRODESULFURIZATION PROCESS, SAID PRIOR PROCESS BEING OPERATED IN A SECOND AND HIGH PRESSURE OF AT LEAST FLOW OPERATION WITH A SECOND FEED OIL AT A PRESSURE OF AT LEAS 600 PSI AND AT A TEMPERATURE BETWEEN 650* AND 800*F. UNTIL SAID CATALYST PERMANENTLY POSSESSED INSUFFICIENT DESULFURIZATION ACTIVITY FOR SAID HIGH PRESSURE PROCESS, SAID CATALYST THEREUPON BEING REMOVED FROM SAID SECOND REACTOR AND CHARGED TO SAID FIRST AND LOW PRESSURE REACTOR FOR HYDROTREATMENT OF SAID FIRST FEED OIL AT A PRESSURE NO HIGHER THAN ABOUT 150 PSI AND AT A TEMPERATURE BETWEEN 400* AND 550*F.
Claim 2
Dependent Claim
139 words
A RELATIVELY LOW PRESSURE HYDROTREATING PROCESS PERFORMED IN A FIRST AND RELATIVELY LOW PRESSURE RECTOR, COMPRISING PASSING A FIRST FEED OIL COMPRISING MIDDLE DISTILLATE STRAIGHT RUN FEED OIL AND HYDROGEN DOWNWARDLY OVER A HYDRODESULFURIZATION CATALYST THAT HAS BEEN DEACTIVATED IN A PRIOR RELATIVELY HIGH PRESSURE HYDRODESULFURIZATION PROCESS, SAID PRIOR PROCESS BEING OPERATED IN A SECOND AND HIGH PRESSURE OF AT LEAST FLOW OPERATION WITH A SECOND FEED OIL AT A PRESSURE OF AT LEAS 600 PSI AND AT A TEMPERATURE BETWEEN 650* AND 800*F. UNTIL SAID CATALYST PERMANENTLY POSSESSED INSUFFICIENT DESULFURIZATION ACTIVITY FOR SAID HIGH PRESSURE PROCESS, SAID CATALYST THEREUPON BEING REMOVED FROM SAID SECOND REACTOR AND CHARGED TO SAID FIRST AND LOW PRESSURE REACTOR FOR HYDROTREATMENT OF SAID FIRST FEED OIL AT A PRESSURE NO HIGHER THAN ABOUT 150 PSI AND AT A TEMPERATURE BETWEEN 400* AND 550*F.
Claim 3
Dependent Claim
27 words
The process of claim 1 wherein not more than 30 weight percent of the total sulfur in the feed oil is removed in the low pressure reactor.
Claim 4
Dependent Claim
17 words
The process of claim 1 wherein said middle distillate feeds boil in the range 350* to 700*F.
Claim 5
Dependent Claim
25 words
The process of claim 1 wherein the catalyst comprises supported Group VI and Group VIII metals and the pressure is no higher than 100 psi.
Claim 6
Dependent Claim
18 words
The process of claim 1 wherein the temperature in said low pressure reactor is between 400* and 550*F.
Claim 7
Dependent Claim
16 words
The process of claim 1 wherein the temperature in said low pressure reactor is below 500*F.
Claim 8
Dependent Claim
16 words
The process of claim 1 wherein the temperature in said low pressure reactor is below 450*F.
Claim 9
Dependent Claim
18 words
The process of claim 1 wherein the LHSV in said low pressure reactor is between 4 and 8.
Claim 10
Dependent Claim
26 words
The process of claim 1 wherein not more than 20 weight percent of the total sulfur in the feed is removed in the low pressure reactor.
Claim 11
Dependent Claim
16 words
The process of claim 1 wherein said middle distillates are furnace oil, kerosene or jet fuel.
Claim 12
Dependent Claim
26 words
The process of claim 1 wherein chemical hydrogen consumption excluding unit losses in said low pressure reactor is less than 10 standard cubic feet per barrel.
Claim 13
Dependent Claim
25 words
The process of claim 1 wherein unit hydrogen consumption including losses in said low pressure reactor is less than 15 standard cubic feet per barrel.
Claim 14
Dependent Claim
17 words
The process of claim 1 wherein the pressure in the low pressure reactor is below 75 psi.
Claim 15
Dependent Claim
27 words
The process of claim 1 wherein the chemical hydrogen consumption in the low pressure reactor is less than 5 standard cubic feet per barrel of feed oil.
Claim 16
Dependent Claim
193 words
A combination first relatively high pressure and second relatively low pressure hydrotreating process comprising passing a first middle distillate straight run oil having a total sulfur content greater than 0.2 weight percent derived from a first crude oil downwardly over a supported Group VI and Group VIII hydrodesulfurization catalyst in a first and high pressure hydrodesulfurization reactor at a pressure above 600 psi and at a temperature between 650* and 800*F. to reduce the total sulfur content of said first oil below 0.2 weight percent until said catalyst is permanently deactivated and possesses insufficient desulfurization activity for said high pressure process, removing said catalyst from said high pressure reactor and passing it to a second and relatively low pressure reactor operated at a pressure below about 150 psi, passing a second middle distillate oil having a total sulfur content less than 0.2 weight percent derived from a second crude oil downwardly over said deactivated catalyst at a pressure no higher than about 150 psi and at a temperature between 400* and 550*F. so that the chemical hydrogen consumption in said second reactor is above 0 but below 10 standard cubic feet per barrel.
Claim 17
Dependent Claim
193 words
A combination first relatively high pressure and second relatively low pressure hydrotreating process comprising passing a first middle distillate straight run oil having a total sulfur content greater than 0.2 weight percent derived from a first crude oil downwardly over a supported Group VI and Group VIII hydrodesulfurization catalyst in a first and high pressure hydrodesulfurization reactor at a pressure above 600 psi and at a temperature between 650* and 800*F. to reduce the total sulfur content of said first oil below 0.2 weight percent until said catalyst is permanently deactivated and possesses insufficient desulfurization activity for said high pressure process, removing said catalyst from said high pressure reactor and passing it to a second and relatively low pressure reactor operated at a pressure below about 150 psi, passing a second middle distillate oil having a total sulfur content less than 0.2 weight percent derived from a second crude oil downwardly over said deactivated catalyst at a pressure no higher than about 150 psi and at a temperature between 400* and 550*F. so that the chemical hydrogen consumption in said second reactor is above 0 but below 10 standard cubic feet per barrel.
Claim 18
Dependent Claim
27 words
The process of claim 15 wherein not more than 30 weight percent of the total sulfur in the feed oil is removed in the low pressure reactor.
Claim 19
Dependent Claim
17 words
The process of claim 15 wherein said middle distillate feeds boil in the range 350* to 700*F.
Claim 20
Dependent Claim
25 words
The process of claim 15 wherein the catalyst comprises supported Group VI and Group VIII metals and the pressure is no more than 100 psi.
Claim 21
Dependent Claim
18 words
The process of claim 15 wherein the temperature in said low pressure reactor is between 400* and 550*F.
Claim 22
Dependent Claim
16 words
The process of claim 15 wherein the temperature in said low pressure reactor is below 500*F.
Claim 23
Dependent Claim
16 words
The process of claim 15 wherein the temperature in said low pressure reactor is below 450*F.
Claim 24
Dependent Claim
18 words
The process of claim 15 wherein the LHSV in said low pressure reactor is between 4 and 8.
Claim 25
Dependent Claim
26 words
The process of claim 15 wherein not more than 20 weight percent of the total sulfur in the feed is removed in the low pressure reactor.
Claim 26
Dependent Claim
16 words
The process of claim 15 wherein said middle distillates are furnace oil, kerosene or jet fuel.
Claim 27
Dependent Claim
26 words
The process of claim 15 wherein chemical hydrogen consumption excluding unit losses in said low pressure reactor is less than 5 standard cubic feet per barrel.
Claim 28
Dependent Claim
21 words
The process of claim 15 wherein there is a color improvement in the middle distillate feed to the low pressure reactor.
Claim 29
Dependent Claim
23 words
The process of claim 15 wherein there is substantially a 100 percent yield in the middle distillate feed to the low pressure reactor.
References Cited (Backward Citations)
US2401334A
Cited
US2717857A
Cited
US2793986A
Cited
US2921023A
Cited
US2963425A
Cited
US2998381A
Cited
US3413216A
Cited
US3483119A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-11-25 | 1978-05-27 | 1978-11-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-11-25 | 1982-05-27 | 1982-11-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-11-25 | 1986-05-27 | 1986-11-26 | $7700.00 | Window Closed / Lapsed |