Process for separating aluminum chloride from silanes

Patent metadata

Field	Value
Publication number	US-10584136-B2
Application number	US-201715576163-A
Country	US
Kind code	B2
Filing date	Apr 3, 2017
Priority date	Apr 12, 2016
Publication date	Mar 10, 2020
Grant date	Mar 10, 2020

Abstract

Aluminum chloride is separated from a silane mixture containing aluminum chloride by reacting the aluminum chloride with a compound reactive therewith which forms an ionic liquid or solid, and separating the ionic liquid or solid from the now-purified silane.

First claim

The invention claimed is:

1. A process for purifying a silane liquid containing aluminium chloride as a contaminant, comprising the following steps, in the order given:
in a first step, adding at least one compound N selected from the group consisting of urea compounds, thiourea compounds, amine compounds, amide compounds, phosphonium compounds, pyridine compounds and imidazolium salt compounds, to the silane liquid containing aluminium chloride as a contaminant, forming an ionic liquid phase from the aluminum chloride and compound(s) N, and
in a second step, separating the ionic liquid from a purified silane liquid which contains a reduced amount of aluminium chloride as compared to the aluminium chloride content of the silane liquid containing aluminium chloride as a contaminant.

2. The process of claim 1 , wherein the silane liquid contains silanes of the formula 1
R a H b SiCl 4-a-b   (1),

where
R each independently is an alkyl radical having from 1 to 6 carbon atoms or a phenyl radical,
a is 0, 1, 2, 3 or 4 and
b is 0, 1 or 2.

3. The process of claim 1 , wherein the silane liquid is a crude silane produced in the Müller-Rochow process.

4. The process of claim 2 , wherein the silane liquid is a crude silane produced in the Müller-Rochow process.

5. The process of claim 1 , wherein the at least one compound N is selected from the group consisting of urea, thiourea, methylimidazolium chloride, and 1-ethyl-2-methylimidazolium chloride.

6. The process of claim 2 , wherein the at least one compound N is selected from the group consisting of urea, thiourea, methylimidazolium chloride and 1-ethyl-2-methylimidazolium chloride.

7. The process of claim 3 , wherein the at least one compound N is selected from the group consisting of urea, thiourea, methylimidazolium chloride and 1-ethyl-2-methylimidazolium chloride.

8. The process of claim 1 , wherein from 2 to 100 parts by weight of compound N are used per 1 part by weight of aluminum chloride in the silane liquid.

9. The process of claim 3 , wherein from 2 to 100 parts by weight of compound N are used per 1 part by weight of aluminum chloride in the silane liquid.

10. The process of claim 1 , wherein the first process step is carried out at a temperature of from 0° C. to 50° C.

11. The process of claim 3 , wherein the first process step is carried out at a temperature of from 0° C. to 50° C.

12. The process of claim 5 , wherein the first process step is carried out at a temperature of from 0° C. to 50° C.

13. The process of claim 8 , wherein the first process step is carried out at a temperature of from 0° C. to 50° C.

14. The process of claim 1 , wherein the first process step is carried out at a temperature of from 0° C. to 30° C.

15. The process of claim 1 , wherein the first process step is carried out at a temperature of from 0° C. to 23° C.

16. The process of claim 1 , wherein the at least one compound N is selected from the group consisting of urea compounds, thiourea compounds, primary and secondary amines, monomeric carboxamides, pyridine, and mixtures thereof.

17. The process of claim 1 , wherein the at least one compound N is selected from the group consisting of urea and thiourea.

18. The process of claim 1 , wherein from 5 to 50 parts by weight of compound(s) N are used per 1 part of aluminum chloride in the silane liquid.

19. The process of claim 3 , wherein the silane liquid contains chlorinated hydrocarbons from the Müller-Rochow process.

Assignees

• Wacker Chemie Ag

Inventors

• Bockholt Andreas
• Mautner Konrad

Classifications

• C07F7/20 Primary

  Purification, separation · CPC title

• C01F7/62 Primary

  Purification · CPC title

• C01B33/10778 Primary

  Purification · CPC title

• C01P2006/80

  Compositional purity · CPC title