US3513085A

US3513085A - Producing isoparaffins and naphthenes from hydrocarbons

Info

Publication number: US3513085A
Application number: US665753A
Authority: US
Inventors: Arnold M Leas
Original assignee: Individual
Current assignee: Individual
Priority date: 1967-09-06
Filing date: 1967-09-06
Publication date: 1970-05-19
Anticipated expiration: 1987-05-19

Description

A. M. LEAS May 19, 1970 PRODUCING ISOPARAFFINS AND NAPHTHENES FROM HYDROCARBONS Filed Sept. 1967 mm mwczowoo 2ocwmoLu 1 why ww mm INVENTOR s G e L M M O n r A why A wow 1 Ow mq P S 1 J ww wm\ EK woo m wh A 223 fi rc m ootxm 3893 22:35 N

E QEQEEIJB ATTORNEY United States Patent "ice 3,513,085 PRODUCING ISOPARAFFINS AND NAPHTHENES FROM HYDROCARBONS Arnold M. Leas, 803 Bellefonte Princess Road, Ashland, Ky. 41101 Filed Sept. 6, 1967, Ser. No. 665,753 Int. Cl. Cg 13/00 US. Cl. 20860 8 Claims ABSTRACT OF THE DISCLOSURE A method for producing isoparaffinic and naphthenic hydrocarbon liquids from hydrocarbon liquids such as coal liquids and petroleum oils, including subjecting at least a part of the feed to a hydrocracking treatment, separating a light liquid fraction from the hydrocracking product boiling below about 600 F., subjecting the light hydrocracking product to solvent extraction to separate an aromatic extract from a non-aromatic railinate, recycling at least a part of the aromatic extract to the hydrocracking treatment, passing the non-aromatic raffinate to a catalytic reforming treatment, fractionating the catalytic reforming product to separate a gas, a material boiling in the gasoline range and a material boiling above the gasoline range, passing the material boiling above the gasoline range to a second solvent extraction step to separate the same into an aromatic extract fraction and a non-aromatic fraction, recycling at least a part of the aromatic extract fraction to the hydrocracking step, passing the non-aromatic rafiinate to a hydrogenation step and recovering an isoparafiinic material from the hydrogenation step. In an alternative operation, a highly aromatic feed may be passed, at least in part, to an alkylation step, alone or together With aromatic extract from the first solvent extraction step, and at least a part of the alkylation product is passed to a hydrogenation step to produce naphthenic hydrocarbons. In still another alternative form of operation, at least a part of the alkylation product is passed to an isomerization step and the product of the isomerization step is passed to the hydrogenation step. Finally, the olefinic materials utilized in the alkylation step may be passed to an isomerization step before passage to the alkylation step.

Field of the invention The present invention rel-ates to a novel process for the production of isoparaffinic and/or naphthenic hydrocarbons. More particularly, the present invention relates to a process for the production of isoparaffinic and/or naphthenic hydrocarbons, particularly useful as jet fuels.

Description of the prior art Although a number of refining techniques have heretofore been proposed for the preparation of isoparaflinic and naphthenic hydrocarbons for use as jet fuels and the like, such techniques have been quite inflexible since they cannot be readily switched from one type of production to the other and ,therefore, are incapable of producing balanced blends of isoparafiins and naphthenes. Secondly, all such processes have been limited to the treatment of petroleum oils and no attention has been paid to the production of jet fuels from coal liquids or combinations of coal liquids with petroleum oils.

3,513,085 Patented May 19, 1970 Summary of the invention It is therefore an object of the present invention to overcome the above-mentioned deficiencies of the prior art. Another object of the present invention is to provide a novel process for producing naphthenic and isoparaffinic hydrocarbons. A still further object of the present invention is to provide an improved technique for producing isoparafiinic and naphthenic hydrocarbons, particularly useful as jet fuels. Another and further object of the present invention is to provide a technique for producing isoparaflinic and naphthenic hydrocarbons which is highly flexible and readily converted to maximization of one product over the other. Another and further object of the present invention is to provide an improved technique for the conversion of coal liquids or coal liquids in combination with petroleum oils to naphthenic and isoparaffinic hydrocarbons, particularly useful as jet fuels.

Description of the preferred embodiments The present invention will be best understood by reference to the accompanying drawing.

In accordance with the present invention, a hydrocarbon liquid feed material, such as liquids derived from normally solid materials such as coal, shale, tar sand, etc., petroleum crude materials, or mixtures of such liquid hydrocarbons, is introduced to the system through line 10. All or a part of this feed is passed through line 12, controlled by valve 14, to a hydrocracking unit 16. Hydrocracking products are separated into a light liquid fraction boiling below about 600 R, which is discharged through line 18, and a heavy liquid product boiling above about 600 F., which is discharged through line 20. All or a part of the light hydrocracking product in line 18 may be passed to a solvent extraction operation 22. In solvent extraction unit 22, the material is separated into an aromatic extract fraction, which is discharged through line 24 and a non-aromatic raflinate fraction discharged through line 26. The non-aromatic raifinate from line 26 is passed to a catalytic reforming unit 28. Reformate from the reforming unit is discharged through line 30 to fractionation column 32. In fractionation column 32, the reformate is separated to produce a gas through line 34, a gasoline range boiling fraction discharged through line 36, and a fraction boiling above gasoline, discharged through line 38. The material from line 38 is passed to a second solvent extraction unit 40. Solvent extraction unit 40 also employs an aromatic selective solvent and separates the material into an aromatic extract discharged through line 42 and a non-aromatic raffinate discharged through line 44. The aromatic extracts from

lines

24 and 42 may be recycled to the hydrocracker through line 46 and valve 48. The non-aromatic raf finate in line 44 is passed to hydrogenation unit 50 Where it is hydrogenated to produce a product containing substantial amounts of isoparaflins. The naphthenic materials may be preduced in one of several Ways. A highly aromatic feed material, passing through line 10, may be passed through line 52 and valve 54 to alkylation unit 56. A light olefinic material may be introduced to the alkylation unit through line 58, line 60 and valve 62. In alkylation unit 56, the aromatics are converted to alkyl aromatics which may be discharged through line 64 and valve 66 to hydrogenation unit 50 or they may be discharged through line 68 and valve 70 to isomerization unit 72. The isomerization product may then be discharged through line 74 to hydrogenation unit 50. The naphthenic products of hydrogenation unit 50 may be discharged through line 76. Hydrogenation unit 50 is shown as a dual unit wherein isoparaffins and naphthenes are produced from two different hydrogenation sections. However, the hydrogenation unit may be a single hydrogenation operation. It is also possible, in accordance with the present invention, to feed light normal olefins to line 78 and valve 80 to isomerization unit 72. In isomerization unit 72, these normal olefins may be converted to isoolefins which are discharged through line 82. The isoolefins may then be used to alkylate the aromatic materials in alkylation unit 56. This product will then be ultimately hydrogenated to produce naphthenes. The isomerization unit may also be a two-unit operation, particularly where olefins are to be isomerized and aromatic materials are to be isomerized at the same time.

The hydrocracking Zone may be a conventional unit operated in two stages containing conventional hydrocracking catalysts, including nickel-oxide or nickel sulfide on silica-alumina, cobalt-molybdenum on alumina, a precious metal on silica-alumina, etc. Such a two-stage unit should employ a more active catalyst in the second stage. Operation of the hydrocracking units is normally at a pressure of at least about 500 p.s.i.g., and preferably 1000 to 3500 p.s.i.g., a temperature from about 400 to 1200 F., and preferably 700 to 850 F., a hydrogen feed rate of about 100 to 20,000 s.c.f. per barrel, and preferably 2,000 to 10,000 s.c.f. per barrel, and a liquid hourly space velocity of about 0.1 to 5.0, and preferably 0.3 to 5.0.

The two aromatic selective solvent separations are also conventional and may employ solvents such as sulfur dioxide, furfural, phenol-water, sulfolane, etc.

The catalytic reforming operation is preferably carried out in the presence of a conventional reforming catalyst, such as a precious metal on alumina. However, the reforming is preferably a low severity treatment at a temperature of about 500 to 850 F. Other suitable conditions include a pressure of about to 1,000 p.s.i.g., and preferably 50 to 200 p.s.i.g., a liquid hourly space velocity between 1 and 20, and preferably 1 and 10, and a hydrogen rate of about 100 to 10,000 s.c.f. per barrel of feed, and preferably 2,000 to 10,000 s.c.f. per barrel.

The alkylation treatment may be carried out in the presence of a solid silica-alumina catalyst with a boron fluoride promoting agent deposited thereon. Suitable operating conditions include a temperature of about 30 to 800 F., and preferably 100 to 450 F., a pressure between about and 2,000 p.s.i.g., and preferably 300 to 1,000 p.s.i.g., and a liquid hourly space velocity of about 0.1 to 20, and preferably 0.5 to 2.0.

Hydrogenation may be carried out in the presence of a precious metal such as platinum on alumina at a temperature of about 100 to 900 F., and preferably 200 to 600 F. A pressure of about 0 to 10,000 p.s.i.g., and preferably 100 to 1,000 p.s.i.g., a liquid hourly space velocity of about 0.1 to 10, and preferably 0.5 to 5.0, and a hydrogen feed rate of about 100 to 3,000, and preferably 500 to 3,000 s.c.f. per barrel of feed may also be employed.

The isomerization operation may be carried out in the presence of a conventional catalyst such as platinum on silica-alumina and under conditions including a temperature of about 800 to 950 F., a pressure of about 50 to 200 p.s.i.g., a liquid hourly space velocity of about 0.5 to 10, and a hydrogen rate of about 500 to 3,000 s.c.f. per barrel of feed.

Having described the present invention with reference to a specific flow diagram and specific examples, it is to be understood that these are not to be considered limiting but that the present invention is to be restricted only by the appended claims.

I claim:

1. A method for producing isoparaffinic hydrocarbons, comprising, subjecting a liquid hydrocarbon feed to a hydrocracking treatment at a pressure of at least 500 p.s.i.g., a temperature between about 400 and 1200 F., a hydrogen feed rate between about 2000 and 10,000 s.c.f. per barrel of feed and a liquid hourly space velocity between about 0.1 and 5.0, subjecting a light liquid hydrocracking product to the action of an aromatic-selective solvent, subjecting the non-aromatic raffinate of the solvent extraction step to a reforming treatment at a pressure between about 0 and 1000 p.s.i.g., a temperature between about 500 and 850 F., a hydrogen feed rate between about and 10,000 s.c.f. per barrel of feed, and a liquid hourly space velocity between about 1 and 20, subjecting a heavy liquid fraction of the reforming step to the action of a second aromatic-selective solvent, and subjecting the non-aromatic raflinate of the second solvent extraction to a hydrogenation treatment at a pressure between about 0 and 10,000 p.s.i.g., a temperature between about 100 and 900 F., a hydrogen feed rate between about 100 and 3000 and a liquid hourly space velocity between about 0.1 and 10.

2. A method in accordance with claim 1 wherein a part of the light hydrocracking product is subjected to an alkylation treatment at a pressure between about 10 and 2,000 p.s.i.g., a temperature between about 30 and 800 F., and a liquid hourly space velocity between about 0.1 and 20.

3. A method in accordance with claim 1 wherein the aromatic extract from the first solvent extraction is recycled to the hydrocracking treatment.

4. A method in accordance with claim 1 wherein the aromatic solvent extract of the first extraction step and the aromatic solvent extract of the second extraction step are recycled to the hydrocracking treatment.

5. A method in accordance with claim 1 wherein a part of the hydrocarbon feed is subjected as an aromatic alkylation treatment at a pressure between about 10 and 2,000 p.s.i.g., a temperature between about 30 and 800 F., and a liquid hourly space velocity between about 0.1 and 20 and the alkylation product is then subjected to the hydrogenation treatment.

6. A method in accordance with claim 1 wherein a part of the aromatic extract from the first and second solvent extraction steps is subjected to an alkylation treatment at a pressure between about 10 and 2,000 p.s.i.g., a temperature between about 30 and 800 F., and a liquid hourly space velocity between about 0.1 and 20 and the alkylation product is subjected to the hydrogenation treatment.

7. A method in accordance with claim 1 wherein an aromatic feed material is subjected to an alkylation treatment at a pressure between about 10 and 2,000 p.s.i.g., a temperature between about 30 and 800 F., and a liquid hourly space velocity between about 0.1 and 20, the alkylation product is subjected to an isomerization treatment at a pressure between about 50 and 200 p.s.i.g. a temperature between about 800 and 950 F., a hydrogen feed rate between about 500 and 3000 s.c.f. per barrel of feed, and a liquid hourly space velocity between about 0.5 and 10, and the isomerization product is subjected to the hydrogenation treatment.

8. A method in accordance with claim 1 wherein an aromatic feed material is subjected to an alkylation treatment at a pressure between about 10 and 2,000 p.s.i.g., a temperature between about 30 and 800 F., and a liquid hourly space velocity between about 0.1 and 20, an olefinic feed containing normal olefins is subjected to an isomerization treatment at a pressure between about 50 and 200 p.s.i.g., a temperature between about 800 and 950 F., a hydrogen feed rate between about 500 and 3,000 s.c.f. per barrel of feed, and a liquid hourly space velocity between about 0.5 and 10, the isomerization product is utilized in the alkylation treatment and the 6 alkylation product is subjected to the hydrogenation 3,304,340 2/1967 N011 260672 treatment.

References Cited DELBERT E. GANTZ, Primary Examiner UNITED STATES PATENTS A. RIMENS, Assistant Examiner 3,132,087 5/1964 Kelly et a1. 30859 5 3,147,206 9/1964 Tulleners 20s 111 3,308,053 3/1967 Kelley et a1 260683.65 208-108; 260-68344, 683.53, 683.65, 683.9, 672