US3193487A - Catalytic hydrogenation of viscosity broken hydrocarbon oils - Google Patents

Description

United States Patent() 3,193,487 CATALYTIC HYDROGENATION F VISCOSITY BROKEN HYDRGCA 0N QILS Harold Beuther, Gibsonia, Richard A. Flinn, Penn Hills Township, Allegheny County, and Bruce K. Schmid, McCandiess Township, Allegheny County, Pa., assignors to Gulf Research & Development Company, Pittsburgh, 1321., a corporation of Delaware No Drawing. Filed Feb. 16, 1961, Ser. No. 89,666 4 Claims. (Cl. 208-68) This invention relates to the treatment of heavy hydrocarbons and in particular to the preparation of more valuable hydrocarbons from residual stocks.

Heavy hydrocarbons and residual stocks are of relatively low value as compared with the more volatile com ponents of petroleum. These lowvalue materials are usually employed as low grade fuels or are subjected to treatments such as visbreaking to'obtain a certain amount of more valuable components and tar-like residues which may be used for roof or road surfacing materials. Also these low grade fractions of petroleum 'have been subjected to hydrogenation under Various conditions in the presence of various catalysts. Although these procedures result in more or less improvement in yields or in the properties of certain portions of the material treated, there is still considerable room for lowering the cost of such treatments and upgrading of the products thus produced.

This invention has for its object to provide improved procedure for preparing more valuable hydrocarbons from low grade petroleum or fractions thereof having a relatively low API gravity. Another object is to provide improved procedure for preparing higher quality fuel oils in higher yield from low quality residues having an API gravity below about 20. A still further object is to provide an improved combination process for upgrading of residual stocks by visbreaking followed by hydrogenation treatment of a type which results in formation of a substantial amount of lower boiling components with concomitant hydrodesulfurization. This procedure may be referred to as either destructive hydrogenation or hydrodesulfurization. A still further object is to improve the state of the art. Other objects will appear hereinafter.

These and other objects of our invention are accomplished by subjecting crude petroleum or a residual fraction thereof having an API gravity below about 20 to a moderate visbreaking to form below about 15 percent gasoline, and subjecting the visbroken product to destructive hydrogenation or hydrodesulfurization catalyst at a pressure between about 500 and 5,000 p.s.i.g. and at a temperature between about 650 and 820 F. The hydrogen-hydrocarbon ratio during this destructive hydrogenation is maintained between about 1000 and 20,000 s.c.f./ bbl. of hydrocarbon charge.

The residual feed stock used in our process may be any crude petroleum having an API gravity below about 20 or any residual fraction thereof having an API gravity of below about 20. There are many crudes which are very viscous and high in asphaltic content and we contemplate the treatment of such crudes without removal of any of their components when they have a gravity below about 20. On the other hand, most crudes are of higher gravity and with such crudes it is desirable to remove valuable portions thereof in conventional manner and 3,l93,487 Patented July 6, 1965 to obtain a residual fraction having a gravity below about 20. This residual fraction may be prepared by atmospheric or vacuum distillation.

The visbreaking operation may be any such operation known in the prior art. These visbreaking operations are commonly carried out by passing the charge stock through a heating coil and heating the oil to thermal cracking temperature. The time of heating, the pressure and the temperature of heating control the amount of thermal cracking or conversion into lower boiling components such as gasoline. In general the temperature may be between about 850 and 975 F., the heating time between about 250 and 1,000 seconds, and the pressure between about 50 and 6,000 p.s.i.g. The conditions are selected so as to result in a moderate degree of cracking, i.e. so as to form less than 15 percent gasoline. It is advantageous to form between about 1 and 15 percent gasoline and preferably between about 5 and 12 percent gasoline. Visbreaking procedures are described in standard textbooks and reference is made thereto for further details on this procedure. See for instance Sachanen, Conversion of Petroleum, Second Edition, Reinhold Publishing Corporation, 1948, pages 252-254. After visbreaking the product is preferably subjected to distillation to remove lower boiling components. We prefer to remove all gasoline and lower boiling components formed during the visbreaking step. However such removal is not necessary and all of the visbroken material may be subjected to the subsequent destructive hydrogenation if desired. With sulfur containing stocks this is advantageous since the lower boiling components which contain sulfur will also be desulfurized during the subseqeunt destructive hydrogenation.

The visbroken residual stock is contacted with hydrogen in the presence of a catalyst such as an oxide or sultide of a Group VI left-hand column metal of the Periodic System. Similarly metals of the iron group, their oxides and sulfides may be employed as catalysts. These Group VI and iron group catalysts may be mixed with one another. For instance an advantageous mixture is a mixture of cobalt and molybdenum oxides or sulfides. Another advantageous mixture is a mixture of nickel and tungsten oxides or sulfides. These catalysts are deposited upon a porous catalyst carrier. Typical useful catalyst carriers are activated alumina, pumice, a silica-alumina cracking catalyst, etc. The pressure during the destructive hydrogenation is maintained between about 500 and 5,000 psi. and preferably is between about 1,000 and 2,000 psi. The temperature may be between about 650 and 820 F. A space velocity between about 0.2 and 10.0 volumes of charge stock per hour per volume of catalyst may be used. As will appear hereinafter, the coupling of moderate visbreaking with a rather severe type of hydrodesulfurization has definite advantages in that the amount of coke deposited during the hydrodesulfurization is greatly reduced as compared with hydrodesulfurization of the same severity applied to a straight run stock or to a more severely visbroken stock. For this reason we prefer to employ relatively severe temperature conditions of between about 750 and 790 F. with a space velocity of between about 0.5 and 4.0 for the destructive hydrogenation or hydrodesulfurization. The hydrogen is present during the reaction in a ratio of between about 1,000 and 20,000 standard cubic feet and preferably between about to obtain more thoroughgoing conversion into a product which is an excellent catalytic cracking'charge stock. These pressures are still moderate as compared with those previously used for destructive hydrogenation. Therefore this conversion to catalytic cracking stock is accomplishedwithout using the relatively high pressures of the destructive hydrogenation prior art. However it is entirely feasible to obtain high yields of fuel oils of improved quality, especially of low sulfur content, by

, carrying out the hydrogen treatment at any pressure between about 500 and 5000 p.s.i.

The following example illustrates the benefits obtained by operating in accordance with our invention.

' EXAMPLE V g A vacuum residue obtained from amixture of Kuwait and Venezuela crudes having the properties shown in Table I was contacted with hydrogen in the presence of a nickel-cobalt-molybdenum catalyst deposited on alumina under the conditions shown in columns 1 and 2 of Table II. The results are given in columns 1 and 2 of Table II.

Table 1 Gravity, API 1 6.8 Viscosity, SUV sec.:

130 F. 915,625 210 F. 8,621 Sulfur, percent 1 4.2 40 Nitrogen, percent 0.47 Carbon residue, percent 19.7 Insoluble in n-pentane, percent 14.9 Insoluble in benzene, percent 0.01 Vanadium, p.p.m. 136 Nickel, p.p.m. 40.1

Table II Column No 1 2 Conditions:

Pressure, p.s.i.g 1, 000 1, 000 Temperature, F 75 790 Hydrogen rate, s.c.f./bbl 8, 420 7,700 Space velocity, vol./l1r./vol- 0.52 0. 50 Throughput, vol./v0l 41.4 40 Run length, hours 80 80 1 e t b wt. of char 0'. Ba ance perc n y g 1.6 2.9 *2 913 Total liquid product. 93. Sulfurremoved 3.1 3.6 Carbon 0. 4 0. 6

Total 98. 8 99. 9

Carbon, percent by wt. of catalyst 20. 4 31. 5 II drogen consum tion:

y S.c.i./b u 837 900 Percent;1 by wt. of charge 1. 3 1. 4 Li uid ro uct inspec ions:

q Gragity, 16. 5 21.9

't sec.: iii ris 3,836 207 1,170 104 Sulfur, percent.- 1:28 0:6; Nitrogen, percent- 0.20 0.36 Carbon residue, percent 12. 2 8. 8 Insoluble in n'Pentane, percent. 6. 4 5. 6 Insoluble in benzene, percent.-- 0,15 0.52 Vanadium, p.p.m 3G. 5 17. 9 Nickel, p.p.m 17. 4 12.9 Pour point, F.. 20

Column No Gasoline HEP-400 F.):

Yield, percent by vol. of charge Inspections:

Gravity, API

Sulfur, percent Hydrocarbon type: percent by vol.:

Aromatics Furnace oil (400-670 F.):

7 Yield, percent by vol. of charge;

Inspections:

-Gravity, API

Sulfur, percent I Nitrogen, percent Hydrocarbon type, percent b Aromatics Oletins. Saturates Bromine N0-- Aniline Pt, F-.- Heavy gas oil (6701,000

' Yields, percent by vol. of charge Inspections:

Gravity, API Viscosity, SUV, se 1 Sulfur, percent Nitrogen, percent Carbon residue, percent Aniline Pt, I Vanadium, p.p.m Nickel, p.p.m K-factor Products produced as described above were subjected to distillation at atmospheric pressure to remove volatile products in a conventional manner. The atmospheric residue thus obtained was then subjected to distillation to obtain a 670 residue and a 1000 F. residue. The properties of the 670 and 1000 F. residues thus obtained are given in Table III.

Table 111 Residue from Residue from Column 1 of Column 2 of Table II Table II Residue cut point F 670 1,000 670 1 000 Yield, percent by vol. of char 84. 6 63. 5 62.3 .4 lnspctionss: 0 API ravi y, 14. 2 11.3 12.7 3. V1scosity, SUV, sec.: 2

492 1, 568 184 2 ,2 Pour point, F. 6O 75 "in? Sulfur 1. 32 1. 54 0.93 1. 60 Nitrogen, percent 0. 49 0. 41 0. 44 0.716 Carbon residue, percent 13.2 17.5 14. 9 31. 7 Insoluble in n-Pentane, percent 8.1 12. 7 9. 5 Insoluble in benzene, percent-. O. 15 0. 11 0. 48 0.29 Vanadium, p.p.m 40. 0 57. 2 l7. 6 44. 5 Nickel, p.p.m 19. 8 26. 0 15. 3 35.9

A vacuum residue obtained by vacuum distillation of a mixture of Kuwait and Venezuela crudes and having the properties shown in Table IV was subjected to visbreaking at three different severities to form gasoline in amounts of 3 percent, 11.8 percent and 20.5 percent re spectively. After removal of the gasoline a part of the residues from each visbreaking operation was contacted with the same nickel-cobalt-molybdenum catalyst mentionedv above in the presence of hydrogen under three different severities (temperatures of 700, 750 and 790 F.) and under the conditions given in Table V. The results of the visbreaking operations as well as the hydrogen treatments are given in Table V.

. Insoluble in benzene, percent oved). oved) breaking at 875 F. (3 gasoline removed). -free VB tar from Visbreaking at 920 F. (11.8% gasoline rem 3 Gasoline-free VB tar from vi 0 F (20.5% gasoline rem 4 SFV at 122 F sbreaking at 96 5,204 seconds. 5 Gasoline from visbreaker, not charged to HDS. saturates.

1 Gasoline-tree VB tar from vis 2 Gasoline Table VI Source of residue Column 1 Column 2 Column 3 Column 4 Column 5 a Table V Table V Table V Table V Table V Residue cut point. F 670 1, 000 670 1, 000 Yield, percent by vol. of charge to HDS 56.6 20.2 90.1 68. Inspections:

Gravity, API 11. 3 1 1.111 3.1 l 1. 083 Viscosity, SUV, sec.:

100 F 7,225 130 F 210 5, 083 146 v 4, 526 35,112 Pour point, 110 80 95 115 Sulfur, Percent. 4. 57 4. 76 2.16 1.11 1.94 4. 88 5.14 Nitrogen, percent 0.50 0.55 0.62 0.52. 0.81 0. 55 0. 65 Carbon residue, percent--. 25. 8 28. 2 r 18.1 15. 41. 2 26. 8 35. 9 Insoluble in n-pentane, percent. 21'. 0 25. 9 13. 5 15. 4 42. 5 24. 9 38. 1 Insoluble in benzene, percent 0.11 0.06 0.09 0.44 1. 68 0.26 0. 21 Vanadium, p.p.m 174 199 78. 9 21.1 73.1 163. 2 224. 3 Nickel, ppm 46.9 52.0 27.4 14.5 45.5 51.1 65.5 Sediment by extraction, percent 0.019 0.015

Source of residue Column 6 Column 9 Table V Table V Residue cut point, F 670 1, 000 670 1, 000 Yield, percent by volume of charge to HDS. 74. 4 43. 0v 67. 8 33. 9 Inspections:

Gravity, API--- 9. 5 2. 4 5. 4 1.112 Viscosity, SUV, s

0 F 339, 464 130 F 210 520 25, 040 893 Pour point, F; 70 115 70 118 75 115 Sulfur, percent 1. 37 1. 85 1.20 1. 96 5.22 5. 97 1. 69 2.41 Nitrogen, percent 0.51 0.63 0.55 0.82 0.65 0.86 0.61 0.86 Carbon residue, percent 18. 1 32. 0 19. 3 43.6 34. 4 47. 6 24. 9 46.2 Insoluble in n-pentane, percent 15.0 26. 7 20. 3 44. 8 38. 9 53. 9 r 7. 6 45.1 'Insoluble in benzene, percent. 0.13 0. 57 0.32 1. 47 6.75 7. 71 1. 74 2. 13 Vanadium, p.p.m 68.3 123 27.4 75.8 231 313 78.9 139 Nickel, p.p.m 29.3 47.9 19. 2 49. 5 59. 6 87.2 35. 4 63.4 Sediment by extraction, percent 0.55

1 Solid gravity, 77 77 F. 2 Beyond scope of method.

The above data showthat our invention gives high yields of gasoline, furnace oil and a #6 fuel oil having a low sulfur content. Also these data show that the invention gives a high yield of distillate products and a low yield of #6 fuel oil and coke as compared with the other procedures. For instance itwill be notcdfrom the above-data that in connection with moderate visbreaking followed by hydrodesulfurization or destructive hydro: genation at more severe conditions of 750 to 790 F.,

there was no increase in coke formation. This is to be compared with a marked increase in coke deposition when a severely visbroken feed is hydrodesulfurized at 750 F. (column 9 of Table V.) This is also to be compared with Table II where the coke deposition from a straight run feed increased considerably on a temperature increase from 750 to 790 F. We have also found that the cyclic content of the products produced by our.

j 15 percent gasoline and subjectingat least the gasolinefree portion of the visbroken material toztreatment with hydrogen in the presence of a catalyst selected from the group consisting of oxides and sulfides ofGroup VI lefthand column and the iron group, at a pressure between about 2000 and 3500 p.s.i., at a temperature between about 650 and 820 F., at a space velocity between about 0.2 and 10 volumes of charge per volume of catalyst per hour, and at a hydrogen recycle rate of between about l000'and 20,000 standard cubic feet per barrel of visbroken hydrocarbon. charge stock.

3. Theprocess which comprises subjecting a member of the group consisting of=crudes, reduced crudes and topped crudes having an API gravity of below about 20 to moderate visbreaking to form between about 3 and about 12 percent gasoline and subjecting at least the gasoline-free portion of the visbroken material to treatment with hydrogen in the presence of a catalyst comgroup consisting of oxides and sulfides of a metal of Group VI left-hand column and the iron group at, a

pressure between about 1000 and 2000 p.s.i., at a temperature between about 650 and 820 F., at a space velocity between about 0.2 and 10 volumes of charge per volume of catalyst per hour, and at a hydrogen recycle rate of between about 1000 and 20,000 standard cubic feet 'per barrel of visbroken hydrocarbon charge stock.

2. The process which comprises subjecting a member of the group consisting of crudcs, reduced crudes and topped crudes having an API gravity of below about 20? V to moderate visbreaking to form between about 1 and prising essentially a mixture of y a member of the group consisting of Group VI oxides and sulfides with a member of the group consisting of iron, cobalt and nickel oxides and sulfides, deposited upon a porous carrier, at a pressure between about 500 and 5000 p.s.i., at a temperature of between about 750 and 790 F., at a space velocity between about 0.5 and 4.0 volumes of charge per volume of catalyst per hour, and. at a hydrogen recycle rate of between about 2000 and 10,000 standard cubic feet per barrel of visbroken hydrocarboncharge stock.

4. The process which comprises subjecting a member of the group consisting of crudes, reduced crudes and topped crudcs having an API gravity of below about 20 to moderate visbreaking to form about 12 percent gasoline and subjecting at least the gasolincvfree portion of the visbroken material to treatment with hydrogen in the presence of a catalyst, comprising essentially a mixture of a member of the group consisting of Group VI oxides and sulfides with a member of the group consisting of iron, cobalt and. nickel oxides and sulfides, deposited upon a porous carrier, at a pressure between about 500 and 5000 9 10 p.s.i., at a temperature of between about 750 and 790 2,666,022 154 Johnson 208-68 F., at a space velocity between about 0.5 and 4.0 volumes 3,008,895 11/61 Hansford et a1 20868 of charge per volume of catalyst per hour, and at a OTHER REFERENCES hydrogen recycle rate of between about 2000 and 10,000 standard cubic feet per barrel of visbroken hydrocarbon 5 Sachanen: Com/H5101! of Petroleum 2nd edltlon charge stock. (1948), pp. 252 and 253, Reinhold Pub. Corp., New York. The Petroleum Handbook, 4th edition, Shell Int. Pet. References Cited by the Examiner Co., Ltd., London, 1959.

UNITED STATES PATENTS ALPHONSO D. SULLIVAN, Primary Examiner. 2,006,177 6/35 Peck 208-68 2345 79 1 6 3 Pier 2O8 68 MILTON STERMAN, Examiner- Disclaimer 3,193,49L-R0bert H. Oramer, Sylvander 0. Eastwood, Woodbury, and Abbott F. H ouser, Cherry Hill, N .J PREPARATION OF A H YDRO- CRACKING CATALYST AND HYDROCRACKING THERE- lVITH. Patent dated July 6, 1965. Disclaimer filed Nov. 20, 1968, by the assignee, Mobil Oil Corporation.

Hereby disclaims the terminal portion of the term of the patent subsequent to July 7,1981.

[Ofiioial Gazette April 1, 1 969.]

Claims (1)

1. THE PROCESS WHICHCOMPRISES SUBJECTING A MEMBER OF THE GROUP CONSISTING OF CRUDES, REDUCED CRUDES AND TOPPED CRUDES HAVING AN API GRAVITY TO BELOW ABOUT 20* TO MODERATE VISBREAKING TO FORM BETWEEN ABOUT 1 AND 15 PERCENT GASOLINE AND SUBJECTING AT LEAST THE GASOLINEFREE PORTION OF THE VISBROKEN MATERIAL TO TREATMENT WITH HYDROGEN IN THE PRESENCE OF A CATALYST SELECTED FROM THE GROUP CONSISTING OF OXIDES AND SULFIDES OF A METAL OF GROUP VI LEFT-HAND COLUMN AND THE IRON GROUP AT A PRESSURE BETWEEN ABOUT 1000 AND 2000 P.S.I., AT A TEMPERATURE BETWEEN ABOUT 650* AND 820*F., AT A SPACE VELOCITY BETWEEN ABOUT 0.2 AND 10 VOLUMES OF CHARGE PER VOLUME OF CATALYST PER HOUR, AND AT A HYDROGEN RECYCLE RATE OF BETWEEN ABOUT 1000 AND 20,000 STANDARD CUBIC FEET PER BARREL OF VISBROKEN HYDROCARBON CHARGE STOCK.