Premixture for preparing an absorbent for removing acidic gases from fluid streams

• US 8,476,475 B2
• Filed: 05/18/2007
• Issued: 07/02/2013
• Est. Priority Date: 05/19/2006
• Status: Active Grant

• Current Assignee: BASF SE
• Original Assignee: BASF SE
• Inventors: Asprion, Norbert
• Primary Examiner(s): McCracken, Daniel C
• Assistant Examiner(s): BERNS, DANIEL J
• Application Number:
  US12/301,477
• Publication Number:
  US 20100204042A1
• Time in Patent Office: 2,237 Days
• Field of Search: 423/210, 423/220, 423/226, 423/228, 423/229, 564/503, 564/506, 544/358
• US Class Current: 564/503
• CPC Class Codes: B01D 53/1462 Removing mixtures of hydrogen sulfide and carbon dioxide
• CPC Class Codes: B01D 53/1493 Selection of liquid materials for use as absorbents
• CPC Class Codes: Y02P 20/151 Reduction of greenhouse gas [GHG] emissions, e.g. CO2

Abstract

A premix is described for producing an absorption medium for removing acid gases from fluid streams. The premix comprises at least one alkanolamine, piperazine and water, the premix having a total amine content of more than 65% by weight, the molar ratio of water to piperazine in the premix being 1.6 to 4.8. The premix is characterized by a low solidification point. It is diluted with water and/or alkanolamine to give the ready-to-use absorption medium.

Claims

1. A premix for producing an absorption medium for removing acid gases from fluid streams comprising at least one alkanolamine, piperazine and water, in which the premix has a total amine content of more than 65% by weight, the piperazine content of the premix is from 20.7 to 41.2% by weight and the molar ratio of water to piperazine in the premix is 1.6 to 4.8, wherein the premix has a solidification point below 35°

C.

2. The premix according to claim 1, in which the molar ratio of water to piperazine in the premix is 1.6 to 3.9.

3. The premix according to claim 1, in which the alkanolamine has the general formula

R¹_nR²_(3-n)N,

where R¹ is hydroxyl-C₂-C₃-alkyl, R² is C₁-C₃-alkyl and n is an integer from 1 to 3.

4. The premix according to claim 3, in which the alkanolamine is selected from methyl-diethanolamine and methyldiisopropanolamine.

5. The premix according to claim 1, in which the alkanolamine is a primary alkanolamine, where a tertiary carbon atom is bound to the amino group.

6. The premix according to claim 5, in which the alkanolamine is 2-amino-2-methyl-propanol.

7. The premix according to claim 1, in which the weight ratio of alkanolamine to piperazine in the premix is 1:

7 to 28;

1.

8. The premix according to claim 7, in which the weight ratio of alkanolamine to piperazine in the premix is 1:

3 to 28;

1.

9. The premix according to claim 1, in which the total amine content is more than 70% by weight.

10. A process for producing an absorption medium for removing acid gases from fluid streams, in which a premix according to claim 1 is mixed with water.

11. The process of claim 10, wherein the premix is additionally mixed with an alkanolamine.

12. The premix of claim 1, wherein the piperazine content of the premix is from 25 to 41.2% by weight.

13. The premix of claim 12, wherein the piperazine content of the premix is from 25 to 29.2% by weight.

14. The premix of claim 12, wherein the piperazine content of the premix is from 28.6 to 34.1% by weight.

15. The premix of claim 12, wherein the piperazine content of the premix is from 33.3 to 41.2% by weight.