Process for producing cyclohexylbenzene
In a process for producing cyclohexylbenzene, benzene and hydrogen are contacted with a catalyst under hydroalkylation conditions to produce an effluent containing cyclohexylbenzene. The catalyst comprises a composite of a molecular sieve, an inorganic oxide different from said molecular sieve and at least one hydrogenation metal, wherein at least 50 wt % of said hydrogenation metal is supported on the inorganic oxide and the inorganic oxide has an average particle size less than 40 μm (microns).
1. A process for producing cyclohexylbenzene, the process comprising contacting benzene and hydrogen with a catalyst under hydroalkylation conditions to produce an effluent containing cyclohexylbenzene, the catalyst comprising a composite of a molecular sieve, an inorganic oxide different from the molecular sieve and at least one hydrogenation metal, wherein at least 50 wt % of the hydrogenation metal is supported on the inorganic oxide and the inorganic oxide has an average particle size less than 40 μm (microns).
2. The process of claim 1 , wherein the inorganic oxide has an average particle size of from 0.01 to 30 μm.
3. The process of claim 1 , wherein the inorganic oxide has an average particle size less than 20 μm.
4. The process of claim 1 , wherein the inorganic oxide has an average particle size less than 5 μm.
5. The process of claim 1 , wherein the inorganic oxide comprises an oxide of at least one element of Groups 2, 4, 13 and 14 of the Periodic Table of Elements.
6. The process of claim 5 wherein the inorganic oxide comprises alumina, titania or zirconia.
7. The process of claim 1 , wherein at least 75 wt % of the hydrogenation metal is supported on the inorganic oxide.
8. The process of claim 1 , wherein the at least one hydrogenation metal is applied to the inorganic oxide before the inorganic oxide is composited with the molecular sieve.
9. The process of claim 8 , wherein the catalyst is produced by depositing the at least one hydrogenation metal on the inorganic oxide and then co-pelletizing a mixture of the metal-containing inorganic oxide and the molecular sieve.
10. The process of claim 8 , wherein the catalyst is produced by depositing the at least one hydrogenation metal on the inorganic oxide and then co-extruding a mixture of the metal-containing inorganic oxide and the molecular sieve.
11. The process of claim 1 , wherein the catalyst further includes a binder.
12. The process of claim 1 , wherein the molecular sieve has an average pore size of at least 7×10 −10 m (7 Angstrom).
13. The process of claim 1 , wherein the molecular sieve is selected from zeolite beta, zeolite X, zeolite Y, mordenite and a molecular sieve of the MCM-22 family.
14. The process of claim 1 , wherein the molecular sieve has an X-ray diffraction pattern including d-spacing maxima at 12.4±0.25, 6.9±0.15, 3.57±0.07 and 3.42±0.07 Angstrom.
15. The process of claim 1 , wherein the molecular sieve is selected from MCM-22, PSH-3, SSZ-25, ERB-1, ITQ-1, ITQ-2, MCM-36, MCM-49, MCM-56, UZM-8, and combinations of any two or more thereof.
16. The process of claim 1 , wherein the molecular sieve is an aluminosilicate and the molar ratio of the aluminum in the molecular sieve to the hydrogenation metal is from 1.5 to 1500.
17. The process of claim 16 wherein the molar ratio is from 100 to 300.
18. The process of claim 1 , wherein the at least one hydrogenation metal is selected from palladium, ruthenium, nickel, zinc, tin, and cobalt.
19. The process of claim 1 , wherein the molar ratio of hydrogen to benzene in the contacting is in the range of from 0.15:1 to 15:1.
20. The process of claim 1 , wherein the hydroalkylation conditions include a temperature of 100 to 400° C. and/or a pressure of 100 to 7000 kPaa.
21. The process of claim 1 , wherein the effluent also contains dicyclohexylbenzene and at least part of the dicyclohexylbenzene is contacted with benzene under transalkylation conditions to produce further cyclohexylbenzene.
22. A method for coproducing phenol and cyclohexanone, the method comprising producing cyclohexylbenzene by the process of claim 1 , oxidizing the cyclohexylbenzene to produce cyclohexylbenzene hydroperoxide and cleaving the cyclohexylbenzene hydroperoxide to produce phenol and cyclohexanone.
23. The method of claim 22 , further comprising dehydrogenating the cyclohexanone to form further phenol.
24. A process for producing cyclohexylbenzene, the process comprising contacting benzene and hydrogen with a catalyst under hydroalkylation conditions to produce an effluent containing cyclohexylbenzene, the catalyst comprising a composite of a molecular sieve, an inorganic oxide different from the molecular sieve and at least one hydrogenation metal, wherein at least 50 wt % of the hydrogenation metal is supported on the inorganic oxide and the inorganic oxide has an average particle size less than 40 μm (microns) wherein the molecular sieve is selected from MCM-22, PSH-3, SSZ-25, ERB-1, ITQ-1, ITQ-2, MCM-36, MCM-49, MCM-56, UZM-8, and combinations of any two or more thereof.
25. A process for producing cyclohexylbenzene, the process comprising contacting benzene and hydrogen with a catalyst under hydroalkylation conditions to produce an effluent containing cyclohexylbenzene, the catalyst comprising a composite of a molecular sieve, an inorganic oxide different from the molecular sieve and at least one hydrogenation metal, wherein at least 75 wt % of the hydrogenation metal is supported on the inorganic oxide and the inorganic oxide has an average particle size average particle size of from 0.01 to 30 μm (microns).