Claims
- 1. A hydroconversion process for converting a heavy hydrocarbonaceous oil to lower boiling products, which process comprises the steps of:
- (a) forming a mixture of a hydrocarbonaceous oil blend comprised of about 22 to about 85 wt.% of a heavy hydrocarbonaceous oil boiling above about 1050.degree. F. with the remainder a lighter hydrocarbonaceous oil, and an oil dispersible, or decomposable, metal compound in an amount ranging from about 0.1 to about 2 weight percent, calculated as elemental metal, based on the weight of said hydrocarbonaceous oil blend, said metal being selected from the group consisting of Groups II, III, IV, V, VIB, and VIII and mixtures thereof, of the Periodic Table of the Elements;
- (b) heating said mixture in the presence of a sulfiding agent at a temperature of at least about 500.degree. F. for an effective amount of time to convert the oil-dispersible, or decomposable, metal compound to the corresponding metal-containing catalyst thereby forming a catalyst concentrate;
- (c) introducing at least a portion of said catalyst concentrate into a hydroconversion zone containing a heavy hydrocarbonaceous chargestock and a supported catalyst comprised of (i) a metal selected from Groups VIB and VII of the Periodic Table of the Elements; and (ii) a refractory inorganic support material;
- (d) subjecting the mixture in the hydroconversion zone to a temperature of about 700.degree. to 900.degree. F., in the presence of an effective amount of a hydrogen-containing gas, at a hydrogen partial pressure from about 100 to 5000 psig, thereby producing lower boiling hydrocarbonaceous products.
- 2. The process of claim 1 wherein the blend contains from about 30 to 85 wt. % heavier oil.
- 3. The process of claim 2 wherein the blend contains from about 45 to 75 wt. % heavier oil.
- 4. The process of claim 1 wherein said heavy hydrocarbonaceous oil of step (a) comprises a blend of a gas oil and a vacuum residuum.
- 5. The process of claim 1 wherein said heavy hydrocarbonaceous oil of step (a) is an atmospheric distillation residuum.
- 6. The process of claim 1 wherein said oil dispersible metal compound is mixed with said heavy hydrocarbonaceous oil in step (a) in an amount ranging from about 0.2 to about wt. %, calculated as elemental metal, based on said heavy oil.
- 7. The process of claim 1 wherein said oil dispersible metal compound is selected from the group consisting of inorganic metal compounds, salts of organic acids, organometallic compounds, salts of organic amines, and mixtures thereof.
- 8. The process of claim 1 wherein said metal of said oil dispersible metal compound is selected from the group consisting of molybdenum, chromium, vanadium, and mixtures thereof.
- 9. The process of claim 1 wherein said oil dispersible metal compound is a phosphomolybdic acid.
- 10. The process of claim 1 wherein the refractory inorganic support of step (b) is selected from the group consisting of alumina, silica, and alumina-silica.
- 11. The process of claim 1 wherein the sulfiding agent is selected from the group consisting of a hydrogen sulfide containing gaseous stream, elemental sulfur, carbon disulfide, compounds that decompose to yield sulfur moieties, and a hydrocarbon stream containing more than 0.1 wt. % sulfur.
- 12. The process of claim 11 wherein the sulfiding agent is a hydrogen sulfide containing gaseous stream containing at least 1 mole % hydrogen sulfide.
- 13. The process of claim 12 wherein the H.sub.2 S/metal ratio is from about 1 to 5.
- 14. The process of claim 1 wherein in step (a): (i) the heavy hydrocarbonaceous oil is a blend of a lighter oil boiling below about 1050.degree. F. and a heavier oil boiling above about 1050.degree. F. which blend contains about 22 to 85 wt. % of heavier oil, (ii) the concentration of oil dispersible metal compound is such that about 0.2 to 1 wt. % calculated is elemental metal is present, based on said oil blend.
- 15. The process of claim 14 wherein the oil dispersible, or decomposable, metal compound is selected from the group consisting of inorganic metal compounds, salts of organic acids, organometallic compounds, and salts of organic amines
- 16. The process of claim 15 wherein the metal is selected from the group consisting of molybdenum, chromium, vanadium, and mixtures thereof.
- 17. The process of claim 16 wherein the oil dispersible metal compound is phosphomolybic acid.
- 18. The process of claim 1 wherein the hydroconversion zone is comprised of one or more reactors which contain an expanded bed of the supported hydrotreating catalyst, which reactors are operated: (i) with a hydrogen flow rate of about 1,000 to 20,000 SCFB; (ii) at a liquid hourly space velocity of about 0.08 to about 1.5 volumes of chargestock per hour per volume of reactor; (iii) at a temperature from about 730.degree. F. to about 850.degree. F.; and (iv) at a hydrogen partial pressure of about 1,000 to about 3,000 psia.
- 19. The process of claim 18 wherein the sulfiding agent is selected from the group consisting of a hydrogen sulfide containing gaseous stream, elemental sulfur, carbon disulfide, and compounds that decompose to yield sulfide moieties.
- 20. The process of claim 19 wherein a hydrogen sulfide containing gaseous stream is used as the sulfiding agent wherein the H.sub.2 S/metal mole ratio is from about 1 to 5.
- 21. The process of claim 20 wherein the oil dispersible, or decomposable, metal compound is selected from the group consisting of inorganic metal compounds, salts of organic acids, organometallic compounds, salts of organic amines.
- 22. The process of claim 21 wherein the metal of the oil dispersible, or decomposable, metal compound is selected from the group consisting of molybdenum, chromium, vanadium, and mixtures thereof.
- 23. The process of claim 22 wherein the oil dispersible metal compound is phosphomolybdic acid.
- 24. The process of claim 23 wherein the refractory inorganic support material of step (c) is selected from the group consisting of alumin, silica, and alumina-silica.
CROSS REFERENCE TO RELATED APPLICATIONS
This is a continuation of application Ser. No. 243,376, filed Sept. 12, 1988, now abandoned, which is a continuation-in-part of U.S. Serial No. 033,682, filed Apr. 3, 1987, now U.S. Pat. No. 4,793,916, which is a continuation-in-part of Serial No. 773,595, Filed Sept. 9, 1985, now abandoned, which is a continuation-in-part of Serial No. 682,379, filed Dec. 17, 1984 now abandoned.
1. Field of the Invention
This invention relates to an improvement in a catalytic hydroconversion process utilizing both an unsupported metal-containing catalyst prepared from a catalyst precursor dispersed in a hydrocarbonaceous oil and a supported catalyst composition.
2. Description of Information Disclosures
There is substantial interest in the petroleum industry for converting heavy hydrocarbonaceous feedstocks to lower boiling liquids and gases. One type of process is a slurry process utilizing a catalyst prepared in a hydrocarbon oil from a thermally decomposable or oil soluble metal compound catalyst precursor. See, for example, U.S. Pat. Nos. 4,226,742 and 4,244,839.
It is also known to use such catalysts in hydroconversion processes (i.e., coal liquefaction) in which coal particles are slurried in a hydrocarbonaceous material. See, for example, U.S. Pat. Nos. 4,077,867 and 4,111,787.
Another type of process used for converting heavy feedstocks is a process wherein the feedstock is subjected to hydroconversion conditions in an expanded, or ebullating, bed of hydrotreating catalyst, such as Ni/Mo or Co/Mo on alumina. See, for example, U.S. Pat. Nos. 4,549,957 and 4,657,665.
The term "hydroconversion" as used herein refers to a catalytic process conducted in the presence of hydrogen in which at least a portion of the heavy constituents of a hydrocarbonaceous oil is converted to lower boiling products. It may also simultaneously reduce the concentration of nitrogenous compounds, and metallic constituents.
All boiling points referred to herein are atmospheric pressure equivalent boiling points unless otherwise specified.
It has been found that introducing a catalyst precursor mixed in relatively large amounts in a hydrocarbonaceous oil (i.e., catalyst precursor concentrate) into a hydroconversion zone containing a heavy hydrocarbonaceous chargestock has certain advantages when compared with a process wherein the catalyst precursor is introduced into the hydroconversion zone without first forming a concentrate; that is, by introducing the catalyst precursor directly into the feed in the reactor. The advantages include: (i) ease of mixing the precursor with a small stream instead of the whole feed; (ii) the ability to store the precursor concentrate for future use and/or activity certification; and (iii) the ability to use a hydrocarbonaceous oil, other than the feedstock, as dispersing medium for the catalyst precursor, which hydrocarbonaceous oil other than the feedstock can be more optimum for developing catalyst activity.
Further, it has now been found that pre-treating a catalyst precursor mixed in relatively large amounts with a hydrocarbonaceous oil (i.e., catalyst precursor concentrate) to convert the catalyst precursor to a solid catalyst in the oil, and subsequently introducing at least a portion of the resulting catalyst concentrate into the hydrocarbonaceous chargestock to be hydroconverted will provide certain advantages. Such advantages include greater flexibility of conditions, for example, use of higher concentrations of sulfiding agent than the concentrations that would be used to treat the total charge-stock, flexibility of heat balance, and economy of energy. Treatment of only the catalyst precursor concentrate also permits reduction of size of equipment needed compared to treatment of the catalyst precursor in the total chargestock. Furthermore, preparing a catalyst concentrate permits storing the catalyst concentrate to use as needed on-site or to send to another site.
In accordance with the present invention there is provided a process for converting heavy hydrocarbonaceous feedstocks to lower boiling products. The process comprises:
(a) forming a mixture of a heavy hydrocarbonaceous oil and a dispersible, or decomposable, metal compound, said metal being selected from the group consisting of Groups II, III, IV, V, VIB, VIIB, and VIII and mixtures thereof of the Periodic Table of the Elements;
(b) introducing at least a portion of said mixture into a hydroconversion zone containing a heavy hydrocarbonaceous chargestock and a supported catalyst comprised of: (i) a metal selected from Groups VIB and VIII of the Periodic Table of the Elements; and (ii) a refractory inorganic support material;
(c) subjecting the chargestock and catalysts to a temperature of about 700.degree. to 900.degree. F., in the presence of a hydrogen-containing gas, and a hydrogen partial pressure from about 100 to 5000 psig, thereby producing lower boiling products.
In a preferred embodiment of the present invention, prior to introducing the mixture of step (a) into the hydroconversion zone, it is first heated in the presence of a sulfiding agent at a temperature of at least about 500.degree. F. for an effective amount of time to convert the oil-dispersible or decomposable, metal compound to the corresponding metal-containing catalyst in said hydrocarbonaceous oil.
In preferred embodiments of the present invention, the sulfiding agent is selected from the group consisting of hydrogen sulfide, a blend of hydrogen and hydrogen sulfide, elemental sulfur, carbon disulfide and compounds that decompose to yield sulfur moieties which will react with the catalyst precursor. Also suitable are plant streams containing hydrogen sulfide in mixture with other gases, and sulfur-rich hydrocarbon media containing more than 0.1 wt. % sulfur.
In still other preferred embodiments of the present invention, the sulfiding agent is hydrogen sulfide which is present in a ratio of H.sub.2 S to elemental metal of from about 1 to 5.
In other preferred embodiments of the present invention, the concentration of oil dispersible metal compound is such that the concentration of metal is from about 0.1 to 2 wt. %, calculated as elemental metal.
In yet other preferred embodiments of the present invention the oil-dispersible metal compound is selected from the group consisting of inorganic metal compounds, salts of organic acids, organo-metallic compounds, salts of organic amines, and mixtures thereof.
In still other preferred embodiments of the present invention the oil-dispersible metal compound is a phosphosmolybdic acid, and the hydroconversion is conducted in an expanded bed of supported catalyst comprised of Ni/Mo on alumina or Co/Mo on alumina.
US Referenced Citations (7)
| Number |
Name |
Date |
Kind |
| 4111787 |
Aldridge et al. |
Sep 1978 |
|
| 4134825 |
Bearden, Jr. et al. |
Jan 1979 |
|
| 4226742 |
Bearden, Jr. et al. |
Oct 1980 |
|
| 4548700 |
Bearden, Jr. et al. |
Oct 1985 |
|
| 4549957 |
Hensley, Jr. et al. |
Oct 1985 |
|
| 4569752 |
Aldridge et al. |
Feb 1986 |
|
| 4578182 |
Bearden, Jr. et al. |
Mar 1986 |
|
Continuations (1)
|
Number |
Date |
Country |
| Parent |
243376 |
Sep 1988 |
|
Continuation in Parts (3)
|
Number |
Date |
Country |
| Parent |
33682 |
Apr 1987 |
|
| Parent |
773595 |
Sep 1985 |
|
| Parent |
682379 |
Dec 1984 |
|
Patent Grant
5108581
