Method for preparing a mixture of alcohols

Patent metadata

Field	Value
Publication number	US-8933279-B2
Application number	US-201214348709-A
Country	US
Kind code	B2
Filing date	Oct 2, 2012
Priority date	Oct 3, 2011
Publication date	Jan 13, 2015
Grant date	Jan 13, 2015

Abstract

A method for preparing a mixture (M) comprising at least an alcohol (Aj), said method comprising the following steps: i) a step in which at least an alcohol (Ai) in gaseous state is oligomerized, thereby producing a mixture (A); ii) a step in which the mixture (A) is condensed to a gaseous stream and to a liquid stream corresponding to a condensed mixture (A); and iii) a step in which the condensed mixture (A) is hydrogenated in the liquid state.

First claim

The invention claimed is:

1. A process for the preparation of a mixture (M) comprising at least one alcohol (Aj), said process comprising the following stages:
i) a stage of oligomerization of at least one alcohol (Ai) in gas phase, resulting in a mixture (A);
ii) a stage of condensation of said mixture (A), resulting in a gas stream and in a liquid stream corresponding to a condensed mixture (A); and
iii) a stage of liquid-phase hydrogenation of said condensed mixture (A) to obtain said mixture (M) comprising at least one alcohol (Aj).

2. The process as claimed in claim 1 , wherein said stage i) is a dimerization of ethanol.

3. The process as claimed in claim 1 , wherein said mixture (M) comprises butanol.

4. The process as claimed in claim 1 , wherein said mixture (M) comprises several alcohols (Aj) having a linear or branched alkyl chain comprising m carbon atoms, with m being equal to 2 or being from 2 to 20.

5. The process as claimed in claim 1 , wherein said stage i) is carried out in the presence of a catalyst of alkaline earth metal phosphate type.

6. The process as claimed in claim 5 , wherein said catalyst is selected from the group consisting of calcium hydroxyapatites.

7. The process as claimed in claim 6 , wherein the (Ca+M)/P molar ratio of said calcium hydroxyapatite is from 1.5 to 2, M being a metal.

8. The process as claimed in claim 1 , wherein said stage i) is carried out at a temperature of from 100° C. to 500° C.

9. The process as claimed in claim 1 , wherein said stage i) is carried out at a pressure of from 0.3 bar to 6 bars absolute.

10. The process as claimed in claim 5 , wherein said at least one alcohol (Ai) of stage i) has a flow rate from 1 to 10 g of said at least one alcohol (Ai) per hour and per gram of said catalyst.

11. The process as claimed in claim 1 , wherein said liquid-phase hydrogenation stage iii) is carried out in the presence of a metal catalyst selected from the group consisting of Fe, Ni, Co, Cu, Cr, W, Mo, Pd, Pt, Rh and Ru, said metal catalyst being optionally supported.

12. The process as claimed in claim 11 , wherein said metal catalyst is immobilized, in the form of grains or extrudates or in the form of a metal foam.

13. The process as claimed in claim 11 , wherein said metal catalyst is in the form of fine particles.

14. The process as claimed in claim 1 , wherein said liquid-phase hydrogenation stage iii) is carried out at a temperature from 50° C. to 165° C.

15. The process as claimed in claim 1 , wherein said liquid-phase hydrogenation stage iii) is carried out at a pressure from 10 bars to 50 bars.

16. The process as claimed in claim 1 , wherein said liquid-phase hydrogenation stage iii) is carried out in an isothermal or adiabatic and tubular or multitubular fixed bed reactor; or in a catalyst-coated reactor/exchanger; or in a reactor stirred by a self-suction stirrer; or in an ejector of venturi or tubular type.

17. The process as claimed in claim 1 , wherein said condensed mixture (A) is subjected, on conclusion of said stage ii) and before said stage iii), to a stage of separation of said liquid and gas streams, in order to obtain said liquid stream and to remove said gas stream.

18. The process as claimed in claim 1 , further comprising on conclusion of said stage iii), successive distillation stages, in order to separate the different alcohols of said mixture (M), and further comprising stages of recycling said at least one alcohol (Ai).

19. The process as claimed in claim 1 , wherein said at least one alcohol (Ai), employed in said stage i), present in said condensed mixture (A) and which has not reacted, is separated from said at least one alcohol (Ai) present in said condensed mixture (A) by liquid/liquid separation, prior to carrying out said stage iii).

20. The process as claimed in claim 1 , wherein said mixture (M) obtained in said step iii) is devoid of aldehyde entities.

Assignees

• Rhodia Operations

Inventors

• Morvan Didier
• Baussaron Loic
• Bocquenet Gerald
• Jacquot Roland
• Marion Philippe
• Belliere-Baca Virginie

Classifications

• C07C29/17 Primary

  by hydrogenation of carbon-to-carbon double or triple bonds · CPC title

• C07C29/175

  with simultaneous reduction of an oxo group · CPC title

• C07C29/34

  by condensation involving hydroxy groups or the mineral ester groups derived therefrom, e.g. Guerbet reaction · CPC title

• C07C31/12

  containing four carbon atoms · CPC title

• C07C29/80

  by distillation · CPC title