Absorbent tertiary monoalkanolamine solution belonging to the 3-alcoxypropylamine family, and method for removing acidic compounds contained in a gas effluent

Patent metadata

Field	Value
Publication number	US-9486737-B2
Application number	US-201214353502-A
Country	US
Kind code	B2
Filing date	Sep 28, 2012
Priority date	Oct 28, 2011
Publication date	Nov 8, 2016
Grant date	Nov 8, 2016

Abstract

The absorbent solution for removing acidic compounds contained in a gas effluent comprises water and at least one amine that is selected from among tertiary monoalkanolamines that contain an etheric function and belong to the 3-alcoxypropylamine family having general formula (A). The method for removing the acidic compounds contained in a gas effluent involves placing a gas effluent 1 into the column C 1 together with the absorbent solution 4.

First claim

The invention claimed is:

1. A process for the removal of the acid compounds present in a gaseous effluent, in which a stage of absorption of the acidic compounds is carried out by bringing the gaseous effluent into contact with an absorbent solution comprising:
water;
at least one amine corresponding to the following general formula (A):

in which:
R 1 is an alkyl radical including from 1 to 6 carbon atoms,
R 2 , R 3 and R 4 are independently chosen from a hydrogen atom and an alkyl radical including from 1 to 6 carbon atoms,
R 5 is an alkyl radical including from 1 to 6 carbon atoms,
R 6 is an alkyl radical including from 1 to 6 carbon atoms.

2. The process as claimed in claim 1 , in which the gaseous effluent is chosen from natural gas, synthesis gases, combustion flue gases, refinery gases, acid gases resulting from an amine unit, gases resulting from a tail gas reduction unit of the Claus process, biomass fermentation gases, gases from cement works or incinerator flue gases.

3. The process as claimed in claim 1 , in which the gaseous effluent is a natural gas comprising H 2 S and CO 2 used for the selective removal of H 2 S with respect to CO 2 .

4. The process as claimed in claim 1 , wherein the amine of the absorbent solution is selected from the group consisting of:
N-methyl-N-(3-methoxypropyl)-1-amino-2-propanol, N-methyl-N-(3-methoxypropyl)-1-amino-2-butanol, N-ethyl-N-(3-methoxypropyl)-1-amino-2-propanol, N-ethyl-N-(3-methoxypropyl)-1-amino-2-butanol, N-isopropyl-N-(3-methoxypropyl)-1-amino-2-propanol and N-isopropyl-N-(3-methoxypropyl)-1-amino-2-butanol.

5. The process as claimed in claim 1 , wherein the absorbent solution comprises between 10% and 90% by weight of said amine and between 10% and 90% by weight of water.

6. The process as claimed in claim 1 , wherein the absorbent solution further comprises a nonzero amount which is less than 20% by weight of either a primary or secondary amine compound.

7. The process as claimed in claim 6 , wherein said primary or secondary amine compound is chosen from the group consisting of:
MonoEthanolAmine,
N-butylethanolamine,
Aminoethylethanolamine,
Diglycolamine,
Piperazine,
N-(2-hydroxyethyl)Piperazine,
N-(2-aminoethyl)Piperazine,
Morpholine,
1,6-hexanediamine, and
N,N′-dimethyl-1,6-hexanediamine.

8. The process as claimed in claim 1 , wherein the absorbent solution further comprises a physical solvent selected from the group consisting of methanol and sulfolane.

9. The process as claimed in claim 1 , in which the stage of absorption of the acid compounds is carried out at a pressure of between 1 bar and 120 bar and at a temperature of between 20° C. and 100° C.

10. The process as claimed in claim 9 , in which the stage of absorption of the acid compounds is carried out at a pressure of between 20 bar and 100 bar.

11. The process as claimed in claim 1 , in which, after the absorption stage, a gaseous effluent depleted in acid compounds and an absorbent solution laden with acid compounds are obtained and at least one stage of regeneration of the absorbent solution laden with acid compounds is carried out.

12. The process as claimed in claim 11 , in which the regeneration stage is carried out at a pressure of between 1 bar and 10 bar and at a temperature between 100° C. and 180° C.

13. The process as claimed in claim 12 , in which the regeneration stage is carried out at a temperature between 155° C. and 180° C.

Assignees

• Ifp Energies Now

Inventors

• Delfort Bruno
• Le Pennec Dominique
• Grandjean Julien

Classifications

• B01D53/1493

  Selection of liquid materials for use as absorbents · CPC title

• B01D2258/0283

  Flue gases · CPC title

• B01D53/526 Primary

  Mixtures of hydrogen sulfide and carbon dioxide · CPC title

• B01D2258/0233

  from cement factories · CPC title

• B01D2251/80

  Organic bases or salts · CPC title