Claims
- 1. In a process for hydrotreating a hydrocarbon, wherein a hydrocarbon charge is contacted with hydrogen in the presence of a supported heterogeneous hydrotreatment catalyst, and wherein said process is subject to catalyst deactivation by pore mouth plugging,
- the improvement wherein said catalyst comprises a carrier and at least one catalytic metal or compound of a catalytic metal, said metal or at least one of the metals being vanadium, molybdenum, tungsten, nickel, cobalt or iron, wherein said catalyst consists of a plurality of juxtaposed agglomerates each formed of a plurality of acicular platelets, the platelets of each agglomerate being oriented generally radially with respect to one another and with respect to the center of the agglomerate; wherein said catalyst contains a major proportion of wedge-shaped mesopores, and has an improved resistance to pore mouth plugging compared with bimodal or monomodal porous catalysts.
- 2. A process according to claim 1, wherein in said catalyst, the agglomerates have an average size between about 1 and 20 micrometers, the acicular platelets having an average length between about 0.05 and 5 micrometers, a ratio of their average length to their average width between about 2 and 20 and a ratio of their average length to their average thickness between about 1 and 5000.
- 3. A process according to claim 1, wherein said catalyst carrier is alumina, whose specific surface is between 50 and 250 m.sup.2 /g, whose total pore volume is between 0.7 and 2.0 cm.sup.3 /g and whose pore distribution is:
- 0-10% of the total pore volume as pores of an average diameter lower than 10 nanometers,
- 40-90% of the total pore volume as pores of an average diameter between 10 and 100 nanometers,
- 5-60% of the total pore volume as pores of an average diameter between 100 and 500 nanometers,
- 5-50% of the total pore volume as pores of an average diameter between 500 and 1000 nanometers
- 5-20% of the total pore volume as pores of an average diameter greater than 1000 nanometers.
- 4. A process according to claim 1, wherein said catalyst carrier is alumina comprising 100 to 1000 ppm of silica.
- 5. A process according to claim 1, wherein said catalyst is manufactured by a process which comprises the steps of:
- (a) treating agglomerates of activated alumina in an aqueous medium consisting essentially of a mixture of (i) at least one aqueous acid to dissolve at least a portion of the alumina of the agglomerates to form aluminum ions, and (ii) at least one compound different than said acid and providing anions; said anions being able to combine with the aluminum ions in solution;
- (b) simultaneously or subsequently subjecting the acid-treated agglomerates to a heat treatment at a temperature between about 80.degree. C. and 250.degree. C. for a period of from about 5 minutes to about 36 hours the combination of steps (a) and (b) resulting in a modification of the distribution of the pore size of the treated agglomerates in relation to the untreated agglomerates pound.
- 6. A process according to claim 5, wherein said step (d) is effected by impregnating the agglomerates with an aqueous, organic or aqueous-organic solution of at least one compound of at least one of vanadium, molybdenum, tungsten, nickel, cobalt or iron, then drying the agglomerates and heating them to about 400.degree. to about 800.degree. C.
- 7. A process according to claim 5, wherein said step (d) is effected by passing a mixture of a hydrocarbon charge with a hydrogenation gas through the agglomerates, said charge comprising, in the dissolved state, at least one compound of at least one of vanadium, molybdenum, tungsten, nickel, cobalt or iron, said compound being in a concentration, x, expressed as weight parts per million with respect to the charge, said hydrogenation gas comprising at least 70% by volume of hydrogen and at least 0.5% by volume of hydrogen sulfide, said passing step being conducted under a total pressure of between 80 and 250 bars at a temperature of between 360.degree. and 420.degree. C., at a space velocity (V.V.N.) of between 0.1 and 2, and at a normalized volume ratio of the gas feed rate to the liquid feed rate of between 500 and 2000, for a time of at least 50,000/x/V.V.H. hours.
- 8. A process according to claim 1, wherein the hydrocarbon charge comprises at least one vanadium, nickel, iron or titanium compound.
- 9. A process according to claim 1, wherein the hydrocarbon charge comprises at least one of sulfur, nitrogen and oxygen.
- 10. A process according to claim 1, wherein in said catalyst, the agglomerates have an average size between 2 and 10 micrometers, the acicular platelets having an average length between 0.1 and 2 micrometers, a ratio of their average length to their average width between 5 and 15, and a ratio of their average length to their average thickness between 10 and 200.
- 11. A process according to claim 3, wherein in said catalyst, said specific surface is 120-180 m.sup.2 /g.
- 12. A process according to claim 3, wherein in said catalyst, said total pore volume is 0.9-1.3 cm.sup.3 /g.
- 13. A process according to claim 1, wherein 40-90% of the total pore volume of said catalyst are mesopores of an average diameter between 10 and 100 nanometers, and not more than 10% of the total pore volume are micropores of an average diameter lower than 10 nanometers.
- 14. A process according to claim 1, wherein in said catalyst, the amount of said catalytic metal or metal compound is 0.5-40% by weight, calculated as the metal oxide.
- 15. A process according to claim 5, wherein the acid used in said step (a) dissolves at least 0.5% and at most 15% by weight of said alumina.
- 16. A process according to claim 5, wherein in said step (a), said acid is nitric, hydrochloric, perchloric or sulfuric acid, at a concentration of 1-15% by weight; and wherein said at least one compound providing an anion able to combine with the aluminum ions is a compound able to liberate nitrate, chloride, sulfate, perchlorate, chloroacetate, dichloroacetate, trichloroacetate, bromoacetate, dibromoacetate, formate, acetate, propionate, butyrate or isobutyrate anions in solution, said compound being an acid, anhydride, salt or ester capable of liberating said anion by dissociation or hydrolysis, said salt being a sodium, potassium, magnesium, calcium, ammonium, aluminum or rare earth metal salt.
- 17. A process according to claim 16, wherein said aqueous medium used in step (a) is a mixture of aqueous nitric and acetic acids, or of aqueous nitric and formic acids.
- 18. A process according to claim 5, wherein in said step (b), the temperature is 120.degree.-220.degree. C., and the treatment time is from 15 minutes to 18 hours.
- 19. A process according to claim 5, wherein the treatment in said step (b) is effected under a partial steam pressure of at least 70% of the saturating vapor pressure at the treatment temperature.
- 20. A process according to claim 1, wherein the hydrotreatment of the hydrocarbon is a hydrodemetallation reaction.
- 21. A process according to claim 20 wherein said contacting is effected at a temperature of about 370.degree.-470.degree. C., under a hydrogen partial pressure of about 50-300 bars, and a space velocity (VVH) of about 0.3-5, the normalized volume ratio of hydrogen gas to liquid hydrocarbon charge being about 200-5000.
- 22. A process according to claim 1, wherein said hydrocarbon charge is a crude oil having an API degree lower than 20, an extract from bituminous sands or shales, an atmospheric or vacuum residue, an asphalt, a deasphalted oil, a deasphalted vacuum residue, a deasphalted crude oil, a heavy fuel oil, an atmospheric or vacuum distillate, or a coal liquefaction product.
- 23. A process according to claim 5, further comprising, in step (c) before subjecting the agglomerates to a thermal activation, drying the agglomerates.
- 24. A process according to claim 23, wherein said drying is effected at a temperature of about 100.degree.-200.degree. C. for a sufficient amount of time to remove water not chemically bound.
- 25. A process according to claim 1, wherein the hydrotreatment of the hydrocarbon is a hydrodesulfuration reaction.
- 26. A process according to claim 1, wherein the hydrotreatment of the hydrocarbon is a hydrodenitrogenation reaction.
- 27. A process according to claim 25, wherein said contacting is effected at a temperature of about 370.degree.-470.degree. C., under a hydrogen partial pressure of about 50-300 bars, and a space velocity (VVH) of about 0.3-5, the normalized volume ratio of hydrogen gas to liquid hydrocarbon charge being about 200-5000.
- 28. A process according to claim 21, wherein said contacting is effected at a temperature of about 370.degree.-470.degree. C., under a hydrogen partial pressure of about 50-300 bars, and a space velocity (VVH) of about 0.3-5, the normalized volume ratio of hydrogen gas to liquid hydrocarbon charge being about 200-5000.
- 29. A process according to claim 1, wherein said contacting is effected at a temperature of about 370.degree. to 470.degree. C. under a hydrogen partial pressure of about 50 to 300 bar, and a space velocity (VVH) of about 0.3 to 5, the normalized volumetric ratio of hydrogen gas to liquid hydrocarbon charge being about 200 to 5000.
Priority Claims (1)
Number |
Date |
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Kind |
82 10757 |
Jun 1982 |
FRX |
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Parent Case Info
This is a division of application Ser. No. 505,557 filed June 17, 1983, now U.S. Pat. No. 4,499,203.
US Referenced Citations (8)
Non-Patent Literature Citations (4)
Entry |
McGraw-Hill, Dictionary of Scientific and Technical Terms, p. 718. |
G. D. Hobson/W. Pohl, Modern Petroleum Technology, pp. 431-433. |
Kirk-Othmer, Encyclopedia of Chemical Technology, 3rd Ed., vol. 17, 1982, pp. 201-206. |
Ullmanns Encyklopaedie der Technischen Chemie, 1975, pp. 690-699. |
Divisions (1)
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Number |
Date |
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Parent |
505557 |
Jun 1983 |
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