Process and catalysts for eliminating sulphur compounds from the gasoline fraction

• US 20030183555A1
• Filed: 04/11/2003
• Published: 10/02/2003
• Est. Priority Date: 10/11/2000
• Status: Active Grant

• Current Assignee: Consejo Superior de Investigaciones Científicas,, Universidad Politecnica De Cataluna
• Original Assignee: Consejo Superior de Investigaciones Científicas,, Universidad Politecnica De Cataluna
• Inventors: Martinez Sanchez, Cristina, Corma Canos, Avelino, Domine, Marcelo Eduardo
• Granted Patent: US 6,846,406 B2
• Time in Patent Office: Days
• US Class Current: 208/208R
• CPC Class Codes: B01J 2229/32 Reaction with silicon compounds, e.g. TEOS, siliconfluoride
• CPC Class Codes: B01J 2229/37 Acid treatment
• CPC Class Codes: B01J 29/0308 Mesoporous materials not having base exchange properties, e.g. Si-MCM-41
• CPC Class Codes: B01J 29/89 Silicates, aluminosilicates or borosilicates of titanium, zirconium or hafnium B01J29/005 takes precedence
• CPC Class Codes: C10G 2400/04 Diesel oil
• CPC Class Codes: C10G 27/12 with oxygen-generating compounds, e.g. per-compounds, chromic acid, chromates plumbites or plumbates C10G19/06

Abstract

The object of the present invention is a process for the elimination of sulphur compounds from the gasoline fraction, characterized in that it comprises carrying out an oxidation reaction of said sulphur compounds using at least one organic-inorganic composite as a catalyst which comprises at least:

Si,

Ti and

silicon linked to carbon

and using organic or inorganic hydro-peroxides as oxidating agents.

According to the process for the present invention, said organic or inorganic composite is obtained by means of a process that comprises a sililation stage during synthesis or by means of a process that comprises a post-synthesis sililation stage.

Claims

1. Process for eliminating sulphur compounds from the gasoline fraction characterized in that it comprises an oxidation reaction of said sulphur compounds using at least one organic-inorganic composite as the catalyst which comprises at least the following:

Si,

Ti and

silicon linked to carbon

and using organic or inorganic hydro-peroxides as oxidation agents.

2. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 1, characterized in that said organic-inorganic composite that comprises at least:

Si,

Ti and

silicon linked to carbon

is obtained by means of a process which is characterized in that the reactant containing the Si—

C groups is added during the synthesis stage.

3. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 1, characterized in that said organic-inorganic composite that includes at least:

Si,

Ti and

silicon linked to carbon

is obtained by means of a process that comprises a post-synthesis sililation stage.

4. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 1, characterized in that said organic-inorganic composite is a microporous molecular sieve that comprises at least:

Si,

Ti and

silicon linked to carbon.

5. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 4, characterized in that said microporous molecular sieve is a sieve with pores formed by rings with 12 or more members selected from zeolite, ALPO and SAPO.

6. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 5, characterized in that said microporous molecular sieve is a sieve selected from among Ti Beta, Ti-ITQ-7, Ti-UTD-1, Ti-Mordenite, Ti-ALPO-5 and Ti-SAPO-5.

7. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 5, characterized in that said microporous molecular sieve is selected from among Beta zeolite, any one of its polymorphs and a mixture thereof.

8. Process for the elimination of sulphur compounds from the gasoline fraction according to one of claim 4, characterized in that said microporous molecular sieve has the following chemical formula in its calcinated and anhydrous state:

y(A_1/nⁿ⁺XO₂);

tTO₂;

SiO₂;

xTiO₂

wherein;

X represents at least one trivalent element,

Y is comprised between 0 and 0.2,

A represents mono-, di- or trivalent cations

n=1, 2 or 3,

T represents at least one tetravalent element other than Si and Ti,

t is comprised between 0 and 1, and

x is comprised between 0.005 and 1000,

and in that said microporous molecular sieve is synthesised in the presence of compounds that contain Si—

C groups or are subject to a post-synthesis sililation stage creating Si—

C bonds.

9. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 6, characterized in that said microporous molecular sieve is synthesised in a medium selected from between a medium that includes F⁻

or a medium that includes OH⁻

anions.

10. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 8, characterized in that said trivalent X element is selected from among Fe, Al, B, Ga, Cr and mixtures thereof.

11. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 8, characterized in that said tetravalent T element is selected from between V and Sn.

12. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 8, characterized in that t is comprised between 0 and 0.2.

13. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 8, characterized in that x is comprised between 0.01 and 100.

14. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 1, characterized in that said organic-inorganic composite is a mesoporous molecular sieve which comprises at least:

Si,

Ti and

silicon linked to carbon.

15. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 14, characterized in that the precursor of the mesoporous molecular sieve used as a catalyst has the following chemical formula:

y(Aⁿ⁺_1/nXO₂);

tTO₂;

(1−

m)S,O₂;

XTiO_2;

mR<sub>(4−

p)</sub>SiO_p/2;

sS

wherein x, A, X, y, n, T, t, S, s have values like those in claim 16 and m is comprised between 10<sup>−

6</sup> and 0.66, p is comprised between 3 and 1, wherein R is an alkyl group, an aromatic group, or combination thereof, which comes from the sililating agent that contains the Si—

C bonds.

16. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 15, characterized in that the organic compound corresponding to group S is extracted by chemical means.

17. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 16, characterized in that the mesoporous molecular sieve is subjected to a post-synthesis treatment with a sililating agent that leads to the formation of new Si—

C bonds.

18. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 14, characterized in that said mesoporous molecular sieve is selected from among Ti-MCM-41, Ti-MCM-48, Ti-HMS, Ti-SBA-15, and Ti-TUD-1.

19. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 14, characterized in that the precursor of the mesoporous molecular sieve used as a catalyst has the following chemical formula:

y(A_1/nⁿ⁺XO₂);

tTO₂;

SiO₂;

xTiO_2;

sS

wherein;

x is comprised between 0.005 and 0.1;

X represents at least one trivalent element,

Y is comprised between 0 and 0.2,

A represents one or more mono-, di- or trivalent compensation cations or mixtures thereof,

n=1, 2 or 3,

T represents tetravalent elements other than Si and Ti,

t is comprised between 0 and 1, and preferably between 0 and 0.2,

S represents an organic compound and

s can vary between 0 and 0.5.

20. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 16, characterized in that said trivalent element is selected from between Fe, Al, B, Ga, Cr and mixtures thereof.

21. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 19, characterized in that said tetravalent T element is selected from between V and Sn.

22. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 19, characterized in that t is comprised between 0 and 0.2.

23. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 19, characterized in that S is selected from among a cationic, anionic and neutral surface active agent.

24. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 19, characterized in that S is a cationic surface active agent selected from among:

a compound of the formula R₁R₂R₃Q⁺ wherein Q is nitrogen or phosphorus and where at least one of the R₁, R₂, R₃ or R₄ substituent is an aryl or alkyl group containing more than 6 atoms of carbon and less than 36, and each one of the remaining R₁, R₂, R₃ or R₄ groups is a hydrogen or aryl or alkyl group with less than five carbons,

a geminal surface active agent with the formula R₁R₂R₃ QR₄QR₁R₂R₃ or R₁R₂R₃Q(R₄R₅QR₆QR₄R₅)Q_nR₁R₂R₃, where Q is a nitrogen or phosphorus and at least one of the R₁- R₆ substituent is an alkyl or aryl group with more than six atoms of carbon and less than 36, and each one of the remaining R₁-R₆ groups are hydrogens or alkyl or aryl groups with less than five atoms of carbon or mixtures thereof, or two of the R₁, R₂, R₃ or R₄ groups can be interconnected leading to cycled compounds.

25. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 19, characterized in that S is a cationic surface active agent selected from cetyl tri-methyl ammonium, dodecyl tri-methyl ammonium, cetyl piridinium, ant cetyl methylphosphonium.

26. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 19, characterized in that S is a cationic surface active agent and is introduced in the composition of the synthesis gel in the form of an hydroxide, halide, nitrate, sulphate, carbonate or silicate or a mixture thereof.

27. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 19, characterized in that S is a neutral surface active agent selected from among:

a compound of the formula R₁R₂R₃Q wherein Q is nitrogen or phosphorus and where at least one of the R₁, R₂, or R₃ substituents is an alkyl or aryl group containing more than 6 atoms of carbon and less than 36, and each one of the remaining R₁, R₂, or R₃ groups is a hydrogen or aryl or alkyl group with less than five carbons,

a compound from formula nR-EO that consists of of alkylpolyethelene oxides, oxides of alkyl-aryl-polyethelene and co-polymers of alkylpolyproylene and alkylethylene, non-limiting examples being the commercial surface active agents denominated Tergitol 15-S-9, Triton X-114, Igepal RC-760, Pluronic 64 L, Tetronic and Sorbitan,

esters derived from fatty acids obtained by a reaction with short chain alcohols, sugars, amino acids and amines, and

polymers or co-polymers derived from polypropylene, polyethylene, polyacrylamide or polyvinyl alcohol.

28. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 19, characterized in that S is a neutral surface active agent selected between lisolecitin, lecitin, dodecyl penta-oxyethelene ether, phosphatidyl di-lauryl di-ethanol amine, di-galactose diglyceride and monogalactose diglyceride.

29. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 19, characterized in that S is a neutral surface active agent selected between dodecylamine, cetylamine and cetylpyridine.

30. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 19, characterized in that S is an anionic surface active agent that responds to the formula RQ⁻

wherein R is an aryl or alkyl group containing more than 6 atoms of carbon and less than 36, and Q is a sulphate, carboxylic or phosphate group.

31. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 19, characterized in that S is an anionic surface active agent selected from among dodecyl sulphate, stearic acid, OT Aerosol and phospholipids.

32. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 19, characterized in that S is an anionic surface active agent selected from among phosphatidyl choline and phosphatyl di-ethanolamine.

33. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 19, characterized in that the organic compound corresponding to the S group is extracted by calcination in air, N₂ or another inert gas at temperatures between 300°

and 700°

C., and is then subjected to a sililation treatment by means of which Si—

C bonds are formed.

34. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 19, characterized in that the organic compound corresponding to the S group is extracted by chemical means and is then subjected to a sililation treatment by means of which Si—

C bonds are formed.

35. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 34, characterized in that said organic compound is extracted by means of treatment with a mineral acid or organic solution in a solvent selected from among water, alcohols, hydrocarbons and a mixture thereof and is then subjected to a sililation treatment by means of which SI—

C bonds are formed.

36. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 19, characterized in that said mesoporous molecular sieve includes Ge, V, Sn or mixtures thereof, as well as Si and Ti.

37. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 34, characterized in that said mesoporous molecular sieve also comprises Al, B, Ga, Fe, Cr or mixtures thereof.

38. Process for the elimination of sulphur compounds from the gasoline fraction according to claims 1, characterized in that said organic-inorganic composite is a mesoporous molecular sieve that comprises at least:

Si,

Ti and

silicon linked to carbon

consists of amorphous inorganic siliceous solids, chemically combined with Ti in a ratio of between 0.2 and 8% by weight of Ti, in the form of an oxide on the total catalyst, and which contain silicon linked to carbon.

39. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 38, characterized in that said amorphous inorganic siliceous solids include at least 90% silica.

40. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 38, characterized in that said amorphous inorganic siliceous solids are pyrogenic silicas selected between cab-o-sil and Aerosil with specific surfaces of between 40 and 450 m²·

g<sup>−

1</sup> and a particle size of between approximately 0.007 and 0.05 microns.

41. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 39, characterized in that said amorphous inorganic siliceous solids are synthetic inorganic oxides of silicon.

42. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 41, characterized in that said synthetic inorganic oxide of silicon is silica gel.

43. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 38, characterized in that said siliceous solid, further to Si and Ti, also comprises elements selected from among V, B, Zr, Mo and mixtures thereof in a percentage of the total weight, and in the form of oxides, of less than 8%.

44. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 38, characterized in that said siliceous solid includes quantities of between 0.01 and 4% by weight of promoters of the alkaline metal or alkali-earth groups or mixtures thereof, in the form of oxides.

45. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 1, characterized in that said oxidation reaction is carried out in a discontinuous reactor, a CSTR reactor, in a fixed bed continuous reactor, in a fluidised bed reactor, or a boiling bed reactor.

46. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 45, characterized in that said oxidation is carried out in a discontinuous reactor, with a weight ratio of the gasoline fraction to the catalyst of between 5 and 200 and a weight ratio between the gasoline fraction and the oxidising agent of between 200 to 10.

47. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 46, characterized in that said weight ratio of the gasoline fraction to the catalyst is comprised between 10 and 100.

48. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 46, characterized in that said weight ratio of the gasoline fraction and the oxidating agent is between 100 and 30.

49. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 1, characterized in that said oxidation reaction is carried out at a temperature of between 10 and 120°

C.

50. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 49, characterized in that said oxidation reaction is carried out at a temperature of between 20 and 80°

C.

51. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 1, characterized in that said oxidation reaction is produced in a reaction time of between 2 minutes and 24 hours.

52. Process for the elimination of sulphur compounds from the gasoline fraction according to claim 1, characterized in that said oxidation reaction includes separation of the products by means of a stage selected between distillation, extraction and both, with a solvent and total or partial re-cycling of the non-reacted products to the reactor.