Process and system for making cyclohexanone

Patent metadata

Field	Value
Publication number	US-9938218-B2
Application number	US-201515324653-A
Country	US
Kind code	B2
Filing date	Aug 3, 2015
Priority date	Aug 15, 2014
Publication date	Apr 10, 2018
Grant date	Apr 10, 2018

Abstract

Disclosed are processes and systems for making cyclohexanone from a mixture comprising phenol, cyclohexanone, and cyclohexylbenzene, comprising a step of or a device for subjecting at least a portion of the mixture to hydrogenation and a step of or a device for distilling a phenol/cyclohexanone/cyclohexylbenzene mixture to obtain an effluent rich in cyclohexanone.

First claim

The invention claimed is:

1. A process for making cyclohexanone, the process comprising:
(A) feeding hydrogen and a hydrogenation feed into a hydrogenation reaction zone, the hydrogenation feed comprising, based on the total weight of the hydrogenation feed:
phenol at a concentration in a range from 10 wt % to 99 wt %;
cyclohexanone at a concentration in a range from 0.1 wt % to 50 wt %;
cyclohexylbenzene at a concentration in a range from 0.001 wt % to 30 wt %; and
bicyclohexane at a concentration in a range from 0.001 wt % to 30 wt %; and
(B) contacting at least a portion of the phenol with at least a portion of the hydrogen in the hydrogenation reaction zone in the presence of a hydrogenation catalyst under hydrogenation reaction conditions such that at least a portion of the phenol is converted to cyclohexanone; wherein at least one of the following conditions (i), (ii), (iii), and (iv) is met:
(i) the conversion of phenol is in a range from 30% to 95%;
(ii) the conversion of cyclohexylbenzene is in a range from 0.1% to 20%;
(iii) the selectivity of phenol to cyclohexanone is in a range from 80% to 99.9%; and
(iv) the selectivity of phenol to cyclohexanol is in a range from 0.1% to 20%,
wherein in step (B) a hydrogenation reaction product is obtained, and the process further comprises:
(F) feeding at least a portion of the hydrogenation reaction product into a first distillation column; and
(G) obtaining from the first distillation column:
a first upper effluent comprising cyclohexanone at a concentration higher than in the hydrogenation reaction product; and
a first middle effluent comprising cyclohexanone at a concentration lower than in the hydrogenation reaction product, and phenol at a concentration higher than in the hydrogenation reaction product.

2. The process of claim 1 , wherein:
the hydrogenation feed further comprises cyclohexenone at a concentration in a range from 0.01 wt % to 5 wt %; and
in step (B), the conversion of cyclohexenone is in a range from 85% to 100%.

3. The process of claim 1 , wherein in step (B), the hydrogenation catalyst has an adsorption affinity of phenol higher than an adsorption affinity of cyclohexanone.

4. The process of claim 1 , wherein in step (B), the hydrogenation catalyst has an adsorption affinity of phenol higher than an adsorption affinity of cyclohexylbenzene.

5. The process of claim 1 , wherein in step (B), the hydrogenation catalyst comprises a hydrogenation metal and an inorganic support material.

6. The process of claim 5 , wherein in step (B), the hydrogenation catalyst comprises a hydrogenation metal selected from Fe, Co, Ni, Ru, Rh, Pd, Ag, Re, Os, Ir, and Pt at a concentration in a range from 0.001 wt % to 5.0 wt %, based on the total weight of the catalyst.

7. The process of claim 5 , wherein in step (B), the inorganic support material is selected from activated carbon, Al 2 O 3 , Ga 2 O 3 , SiO 2 , GeOo, SnO, SnO 2 , TiO 2 , ZrO 2 , Sc 2 O 3 , Y 2 O 3 , alkali metal oxides, alkaline earth metal oxides, and mixtures, combinations, complexes, and compounds thereof.

8. The process of claim 5 , wherein the hydrogenation metal is preferentially distributed on the outer rim of the catalyst.

9. The process of claim 1 , wherein in step (B), the hydrogenation reaction conditions comprise a temperature in a range from 140° C. to 300° C.

10. The process of claim 1 , wherein in step (B), the hydrogenation reaction conditions comprise an absolute pressure in a range from 100 kPa to 400 kPa, such that in the hydrogenation reaction zone at least one of the following conditions is met:
(i) at least 90% of the cyclohexylbenzene is present in vapor phase; and
(ii) at least 90% of the phenol is present in vapor phase.

11. The process of claim 1 , wherein in step (B), the hydrogenation reaction conditions comprise an absolute pressure in a range from 375 kPa to 1200 kPa, such that in the hydrogenation reaction zone at least one of the following conditions is met:
(i) at least 50% of the cyclohexylbenzene is present in liquid phase; and
(ii) at least 50% of the phenol is present in liquid phase.

12. The process of claim 1 , wherein hydrogen and phenol are fed into the hydrogenation reaction zone at a hydrogen to phenol molar ratio in a range from 1.0 to 10.

13. The process of claim 1 , wherein in step (B), at least 95% of the hydrogen fed into the hydrogenation reaction zone is consumed.

14. The process of claim 1 , wherein the hydrogenation reaction product comprises hydrogen vapor, and the process further comprises:
(D) separating the hydrogenation reaction product into a vapor stream comprising hydrogen and a liquid stream; and
(E) recycling at least a portion of the vapor stream into the hydrogenation reaction zone.

15. The process of claim 1 , wherein in step (G), the following is further obtained:
a first lower effluent comprising cyclohexylbenzene at a concentration higher than in the hydrogenation reaction product.

16. The process of claim 1 , wherein the hydrogenation reaction zone comprises a plurality of hydrogenation reactors connected in series and/or in parallel.

17. A system configured to implement a process of claim 1 for making cyclohexanone, the system comprising:
(I) a hydrogenation reaction zone configured to receive hydrogen and a hydrogenation feed comprising cyclohexanone, phenol, cyclohexylbenzene, and bicyclohexane, where phenol reacts with hydrogen in the presence of a hydrogenation catalyst under hydrogenation conditions to produce a hydrogenation reaction product comprising cyclohexanone at a concentration higher than the hydrogenation feed, phenol at a concentration lower than the hydrogenation feed, cyclohexylbenzene, and bicyclohexane; and
(II) a first distillation column configured to
(i) receive at least a portion of the hydrogenation reaction product; and
(ii) produce:
a first upper effluent comprising cyclohexanone, phenol, and cyclohexylbenzene;
a first middle effluent comprising cyclohexanone, phenol, and cyclohexylbenzene, and bicyclohexane; and
a first lower effluent comprising cyclohexylbenzene; and

(III) a fluid communication configured to deliver at least a portion of the first middle effluent to the hydrogenation zone.

Assignees

• Exxonmobil Chemical Patents Inc

Inventors

• Becker Christopher L
• Davis Jason D
• Dakka Jihad M
• Nadler Kirk C

Classifications

• B01D3/36

  Azeotropic distillation · CPC title

• B01D3/14

  Fractional distillation {or use of a fractionation or rectification column} · CPC title

• C07C45/82

  by distillation · CPC title

• C07C45/006 Primary

  by hydrogenation of aromatic hydroxy compounds · CPC title

• C07C49/403

  of a six-membered ring · CPC title