Method for producing silicic acid with variable thickening

Patent metadata

Field	Value
Publication number	US-10280088-B2
Application number	US-201414888610-A
Country	US
Kind code	B2
Filing date	Jun 13, 2014
Priority date	Jul 11, 2013
Publication date	May 7, 2019
Grant date	May 7, 2019

Abstract

Process for production of silica having variable thickening wherein
a) a product stream I comprising at least a vaporous, hydrolysable and/or oxidizable silicon compound, b) a product stream II comprising oxygen and c) a product stream III comprising at least a combustible gas are made to react, characterized in that d) a feed port in a pipepiece A, said pipepiece A comprising one or more static mixing elements, is used to import product stream I into product stream II, or vice versa and thereby create product stream IV, then e) a feed port in a pipepiece B, said pipepiece B comprising one or more static mixing elements,
is used to import product stream III in product stream IV and thereby create product stream V,
f) product stream V leaving pipepiece B is imported into a reaction chamber, ignited therein and reacted in a flame, and g) the resultant solid material is separated off.

First claim

The invention claimed is:

1. A process for producing silica having variable thickening, the process comprising reacting:
a) a product stream I comprising at least one silicon compound selected from the group consisting of a vaporous silicon compound, a hydrolysable silicon compound, and an oxidizable silicon compound,
b) a product stream II comprising oxygen and
c) a product stream III comprising a combustible gas,
wherein the process comprises:
importing product stream I into product stream II, or importing product stream II into product stream I, through a feed port in a first pipe piece A to create product stream IV, wherein the first pipe piece A comprises at least one static mixing element;
importing product stream III in product stream IV, through a feed port in a second pipe piece B to create product stream V, wherein the second pipe piece B comprises at least one static mixing element;
importing product stream V leaving the second pipe piece B into a reaction chamber, igniting the reaction chamber, and reacting the product stream V in a flame; and
separating solids resulting from the ignition and the reaction,
wherein V B is a velocity with which the product stream III comprising a combustible gas is imported into the product stream IV, V A is a velocity of the product stream IV at a point of importing the product stream III comprising a combustible gas, and

V B /V A ≥4, and
wherein V A is at least 15 Nm/s.

2. The process according to claim 1 , wherein the first and second pipe pieces comprising static mixing elements are designed as a flange mixer.

3. The process according to claim 2 , wherein the flange mixer comprises a single punctiform feed port.

4. The process according to claim 1 , wherein L A /D A is 2-20, where L A is the length of the first pipe piece, D A is the internal diameter of the first pipe piece.

5. The process according to claim 1 , wherein L B /D B is 2-20, where L B is the length of the second pipe piece, D B is the internal diameter of the second pipe piece.

6. The process according to claim 1 , wherein an amount of oxygen is at least sufficient to convert the at least one silicon compound and the combustible gas.

7. The process according to claim 1 , wherein the at least one silicon compound is selected from the group consisting of SiCl 4 , CH 3 SiCl 3 , (CH 3 ) 2 SiCl 2 , (CH 3 ) 3 SiCl, (CH 3 ) 4 Si, HSiCl 3 , (CH 3 ) 2 HSiCl, CH 3 CH 2 CH 2 SiCl 3 , Si(OC 2 H 5 ) 4 , Si(OCH 3 ) 4 and a mixture thereof.

8. The process according to claim 1 , further comprising introducing a stream comprising oxygen and/or steam into the reaction chamber.

9. The process according to claim 1 , further comprising cooling a reaction mixture leaving the reaction chamber to form a cooled reaction mixture and treating the cooled reaction mixture with steam, before separating the solids.

Assignees

• Evonik Degussa Gmbh

Inventors

• Schulze Isfort Christian
• Golchert Rainer
• Roth Helmut
• Hille Andreas
• Schumacher Kai

Classifications

• C01B33/183 Primary

  by oxidation or hydrolysis in the vapour phase of silicon compounds such as halides, trichlorosilane, monosilane · CPC title