Organometallic compound purification

Patent metadata

Field	Value
Publication number	US-9085594-B2
Application number	US-201213549407-A
Country	US
Kind code	B2
Filing date	Jul 13, 2012
Priority date	Jul 13, 2011
Publication date	Jul 21, 2015
Grant date	Jul 21, 2015

Abstract

A method of purifying crude organometallic compounds using a plurality of distillation columns is provided. This method effectively removes both relatively more volatile impurities and relatively less volatile impurities as compared to the organometallic compound.

First claim

What is claimed is:

1. A method of continuously purifying an organometallic compound comprising:
(a) providing a distillation apparatus comprising a first column and a second column, each column having an upper portion and a lower portion;
(b) providing a crude organometallic compound to be purified to the first distillation column;
(c) subjecting the organometallic compound in the first distillation column to conditions sufficient to remove relatively more volatile impurities from the upper portion of the first distillation column;
(d) conveying the organometallic compound from the lower portion of the first distillation column to the second distillation column; and
(e) subjecting the organometallic compound in the second distillation column to conditions sufficient to obtain purified organometallic compound from the upper portion of the second distillation column;

wherein the first distillation column has a number of theoretical stripping stages sufficient to remove of the relatively more volatile impurities from the organometallic compound;
wherein the second distillation column has a number of theoretical rectification stages sufficient to obtain purified organometallic compound; and
wherein the obtained purified organic compound has a purity of ≧95%.

2. The method of claim 1 wherein the purified organometallic compound is obtained in an overall yield of ≧90%.

3. The method of claim 2 wherein the purified organometallic compound is obtained in an overall yield of ≧95%.

4. The method of claim 1 wherein the first distillation column has ≧30 theoretical stages.

5. The method of claim 1 wherein the second distillation column has ≧30 theoretical stages.

6. The method of claim 1 wherein the organometallic compound comprises a Group 13 metal.

7. The method of claim 6 wherein the organometallic compound is trimethyl gallium or triethyl gallium.

8. The method of claim 1 wherein the first distillation column further comprises an outlet and a stripping gas that is conveyed upward through the column and exits the first column through the outlet.

9. The method of claim 1 wherein ≧97% of relatively more volatile impurities are removed from the organometallic compound in the first distillation column.

10. The method of claim 1 wherein the first distillation column has a reflux ratio of ≧45:1.

11. The method of claim 1 wherein the second distillation column has a reflux ratio of ≧10:1.

12. A method of continuously purifying an organometallic compound comprising:
(a) providing a distillation apparatus comprising a first column and a second column, each column having an inlet, an upper portion, a lower portion, and an outlet;
(b) providing a crude organometallic compound to be purified to the first distillation column;
(c) subjecting the organometallic compound in the first distillation column to conditions sufficient to remove ≧97% of relatively more volatile impurities from the upper portion of the first distillation column;
(d) conveying the organometallic compound from the lower portion of the first distillation column to the second distillation column; and
(e) subjecting the organometallic compound in the second distillation column to conditions sufficient to obtain purified organometallic compound from the upper portion of the second distillation column;
wherein the first distillation column has a number of theoretical stripping stages sufficient to remove of the relatively more volatile impurities from the organometallic compound;
wherein the second distillation column has a number of theoretical rectification stages sufficient to obtain purified organometallic compound; and
wherein the obtained purified organic compound has a purity of ≧95%.

13. The method of claim 12 wherein the organometallic compound comprises a Group 13 metal.

14. The method of claim 13 wherein the organometallic compound is trimethyl gallium or triethyl gallium.

15. The method of claim 12 wherein the first distillation column further comprises a stripping gas that is conveyed upward through the column and exits the first column through the outlet.

16. The method of claim 12 wherein the first distillation column has a reflux ratio of ≧45:1.

17. The method of claim 12 wherein the second distillation column has a reflux ratio of ≧10:1.

18. The method of claim 12 wherein the first distillation column has a ratio of theoretical stripping stages to theoretical rectification stages of from >1:1 to 20:1.

19. The method of claim 12 wherein the second distillation column has a ratio of theoretical rectification stages to theoretical stripping stages of from >1:1 to 20:1.

Assignees

• Modtland Curtis D
• Davidson Chet D
• Dow Global Technologies Llc

Inventors

• Modtland Curtis D
• Davidson Chet D

Classifications

• C07F9/90

  Antimony compounds · CPC title

• B01D3/143 Primary

  by two or more of a fractionation, separation or rectification step · CPC title

• B01D3/14 Primary

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

• B01D3/00

  Distillation or related exchange processes in which liquids are contacted with gaseous media, e.g. stripping ({evaporation in general, e.g. of liquids for gas phase reactions B01B1/005;} gas chromatography B01D15/08; destructive distillation C10B; preparation of alcoholic beverages by distillation C12H6/02) · CPC title

• C07F5/00

  Compounds containing elements of Groups 3 or 13 of the Periodic Table · CPC title