Method for producing silicic acid with variable thickening

Patent metadata

Field	Value
Publication number	US-2016107895-A1
Application number	US-201414888610-A
Country	US
Kind code	A1
Filing date	Jun 13, 2014
Priority date	Jul 11, 2013
Publication date	Apr 21, 2016
Grant date	—

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

1 . A process for producing silica having variable thickening, the process comprising:
introducing a stream comprising at least one silicon compound selected from the group consisting of a vaporous silicon compound, a hydrolyzable silicon compound and an oxidizable silicon compound, into a stream comprising oxygen, or vice versa, employing a feed port in a first pipe piece comprising one or more static mixing elements to create a first product stream; introducing a stream comprising at least a combustible gas into the first product stream employing a feed port in a second pipe piece comprising one or more static mixing elements to create a second product stream; introducing the second product stream, which leaves the second pipe piece, into a reaction chamber to ignite the second product stream to react in a flame; and separating solids resulting from the ignition and the reaction.

2 . The process according to claim 1 , wherein the pipe piece comprising static mixing elements is 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 v B is a velocity with which the stream comprising at least a combustible gas is introduced into the first product stream, v A is a velocity of the first product stream at a point of introducing the stream comprising at least a combustible gas, and v B /v A ≧4.

5 . The process according to claim 1 , wherein v A is at least 15 Nm/s.

6 . The process according to claim 1 , wherein v B is ≧50 Nm/s.

7 . 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.

8 . 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.

9 . 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.

10 . 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.

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

12 . 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

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