Method for purifying 1,3-butadiene

Patent metadata

Field	Value
Publication number	US-9676683-B2
Application number	US-201214360674-A
Country	US
Kind code	B2
Filing date	Nov 27, 2012
Priority date	Nov 28, 2011
Publication date	Jun 13, 2017
Grant date	Jun 13, 2017

Abstract

It is an object of the present invention to provide a method for purifying 1,3-butadiene which can effectively remove an organic compound detrimental to anionic polymerization from 1,3-butadiene containing a polymerization inhibitor and suppress the formation of popcorn. The method includes: a water-washing step of washing 1,3-butadiene by using low-oxygen water having an oxygen concentration of less than 2 mg/L as wash water; and a polymerization inhibitor removing step of subsequently removing the polymerization inhibitor in 1,3-butadiene.

First claim

The invention claimed is:

1. A method of purifying 1,3-butadiene, comprising:
washing a 1,3-butadiene stream comprising 1,3-butadiene and a polymerization inhibitor in a water-washing step by using low-oxygen water having an oxygen concentration of less than 2 mg/L as wash water; and
subsequently removing the polymerization inhibitor from the 1,3-butadiene stream in a polymer inhibitor removing step thereby obtaining a purified 1,3-butadiene stream.

2. The method of purifying 1,3-butadiene according to claim 1 , further comprising monitoring a concentration of an impurity in an aqueous phase in the water-washing step.

3. The method of purifying 1,3-butadiene according to claim 1 , comprising subjecting water to an oxygen removing film in a deoxidation treatment to obtain the low-oxygen water.

4. The method of purifying 1,3-butadiene according to claim 1 , further comprising heating the wash water used in the water-washing step to 60° C. or more, so as to remove 1,3-butadiene from the wash water.

5. The method of purifying 1,3-butadiene according to claim 1 , further comprising treating 1,3-butadiene with a deoxidant,
wherein the step of treating with the deoxidant and the polymerization inhibitor removing step are performed after the water-washing step.

6. The method of purifying 1,3-butadiene according to claim 1 , further comprising
diluting the 1,3-butadiene stream with an organic solvent to obtain an mixed liquid of 1,3-butadiene and organic solvent,
supplying the mixed liquid of 1,3-butadiene and organic solvent to a dehydrating column dehydrating the mixed liquid,
extracting the dehydrated mixed liquid of 1,3-butadiene from a column bottom or a column intermediate part of the dehydrating column, and
removing solvent from the mixed liquid stream thereby obtaining the purified 1,3-butadiene stream.

7. The method of purifying 1,3-butadiene according to claim 1 , wherein the low-oxygen water has an oxygen concentration of less than 1 mg/L.

8. The method of purifying 1,3-butadiene according to claim 1 , wherein the low-oxygen water has an oxygen concentration of less than 0.5 mg/L.

9. The method of purifying 1,3-butadiene according to claim 3 , wherein the wash water used in the water-washing step is heated to 80° C. or more.

10. The method of purifying 1,3-butadiene according to claim 5 , wherein the deoxidant is selected from the group consisting of sodium sulfite, sodium hydrogen sulfite, sodium hyposulfite, potassium sulfite, sodium nitrite, and a mixture thereof.

11. The method of purifying 1,3-butadiene according to claim 5 , wherein the deoxidant is in an aqueous solution.

12. A method of purifying 1,3-butadiene comprising:
washing a stream comprising 1,3-butadiene and a polymerization inhibitor in a water-washing step by using low-oxygen water having an oxygen concentration of less than 2 mg/L as wash water and monitoring a concentration of an impurity in an aqueous phase;
subsequently removing the polymerization inhibitor from the stream in a polymerization inhibitor removing step to obtain a 1,3-butadiene stream;
treating the 1,3-butadiene stream comprising 1,3-butadiene with a deoxidant to obtain a treated 1,3-butadiene stream;
diluting the treated 1,3-butadiene stream with an organic solvent to obtain an mixed liquid of 1,3-butadiene and organic solvent,
supplying the mixed liquid of 1,3-butadiene and organic solvent to a dehydrating column dehydrating the mixed liquid,
extracting the dehydrated mixed liquid of 1,3-butadiene from a column bottom or a column intermediate part of the dehydrating column, and
removing solvent from the mixed liquid stream thereby obtaining a purified 1,3-butadiene stream.

13. The method of purifying 1,3-butadiene according to claim 12 , comprising subjecting water to an oxygen removing film in a deoxidation treatment to obtain the low-oxygen water.

14. The method of purifying 1,3-butadiene according to claim 12 , further comprising heating the wash water used in the water-washing step to 60° C. or more, so as to remove 1,3-butadiene from the wash water.

15. The method of purifying 1,3-butadiene according to claim 12 , wherein the step of treating with the deoxidant and the polymerization inhibitor removing step are performed after the water-washing step.

16. The method of purifying 1,3-butadiene according to claim 12 , wherein the low-oxygen water has an oxygen concentration of less than 1 mg/L.

17. The method of purifying 1,3-butadiene according to claim 12 , wherein the low-oxygen water has an oxygen concentration of less than 0.5 mg/L.

18. The method of purifying 1,3-butadiene according to claim 13 , wherein the wash water used in the water-washing step is heated to 80° C. or more.

19. The method of purifying 1,3-butadiene according to claim 12 , wherein the deoxidant is selected from the group consisting of sodium sulfite, sodium hydrogen sulfite, sodium hyposulfite, potassium sulfite, sodium nitrite, and a mixture thereof.

20. The method of purifying 1,3-butadiene according to claim 12 , wherein the deoxidant is in an aqueous solution.

Assignees

• Asahi Kasei Chemicals Corp

Inventors

• Nakahara Tatsuto
• Nakano Hiroshi

Classifications

• C08C2/02

  Purification · CPC title

• C07C7/10

  by extraction, i.e. purification or separation of liquid hydrocarbons with the aid of liquids · CPC title

• C07C7/06

  by azeotropic distillation · CPC title

• C07C7/005 Primary

  Processes comprising at least two steps in series · CPC title

• C07C11/167

  1, 3-Butadiene · CPC title