Spray evaporation of a liquid raw material for preparation of silicon dioxide and metal oxides

Patent metadata

Field	Value
Publication number	US-2020140282-A1
Application number	US-201816628664-A
Country	US
Kind code	A1
Filing date	Jun 27, 2018
Priority date	Jul 5, 2017
Publication date	May 7, 2020
Grant date	—

Abstract

The present invention relates to a process for preparing a metal oxide,
comprising a) spraying a liquid raw material comprising at least one metal compound by mixing it with a gas to form an aerosol;

b) forming a gaseous reaction mixture from the aerosol obtained in step a) by complete evaporation thereof;

c) converting the gaseous reaction mixture obtained in step b) to metal oxide in the presence of oxygen.

First claim

1 - 15 . (canceled)

16 . A process for preparing silicon dioxide and/or a metal oxide, comprising the following steps:
a) spraying a liquid raw material comprising at least one silicon compound and/or a metal compound by mixing it with a gas to form an aerosol; b) forming a gaseous reaction mixture from the aerosol obtained in step a) by complete evaporation thereof; c) converting the gaseous reaction mixture obtained in step b) to silicon dioxide and/or metal oxide in the presence of oxygen.

17 . The process of claim 16 , wherein the aerosol formed in step a) comprises liquid droplets having a numerical average particle size of not more than 2 mm.

18 . The process of claim 16 , wherein the ratio of gas volume in standard cubic metres used in total in steps a) and b) to the amount of the liquid raw material used in kilograms is from 0.1 to 100 m 3 (STP)/kg.

19 . The process of claim 16 , wherein the gas used in step a) and/or b) comprises oxygen.

20 . The process of claim 16 , wherein the liquid raw material is preheated to a temperature of 50 to 500° C. prior to performance of step a).

21 . The process of claim 16 , wherein the gas used in step a) and/or b) is preheated to a temperature of 50 to 400° C.

22 . The process of claim 16 , wherein the liquid raw material used in step a), prior to performance of step a), has a pressure of at least 1.5 bar and the gas mixture obtained in step b) has a pressure of not more than 1.2 bar.

23 . The process of claim 16 , wherein the gaseous reaction mixture used in step c) has a temperature at least 10° C. higher than the dew point temperature of this mixture.

24 . The process of claim 16 , wherein the liquid raw material is sprayed through at least one nozzle.

25 . The process of claim 16 , wherein steps a) and b) take place simultaneously.

26 . The process of claim 16 , wherein a gaseous fuel is used in at least one of steps a)-c).

27 . The process of claim 16 , wherein the metal oxide comprises at least one of the elements Al, Ce, Fe, Mg, In, Ti, Sn, Y, Zn and/or Zr as the metal component.

28 . The process of claim 16 , wherein a silicon compound is used for preparation of silicon dioxide.

29 . The process of claim 28 , wherein the silicon compound is a non-halogenated compound selected from the group consisting of: tetraalkoxyorthosilicates; silanes; silicone oils; polysiloxanes and cyclic polysiloxanes; silazanes; and mixtures thereof.

30 . The process of claim 28 , wherein the silicon compound is a chlorinated compound selected from the group consisting of: silicon tetrachloride; dichlorosilane; trichlorosilane; methyltrichlorosilane; dimethyldichlorosilane; methyldichlorosilane; dibutyldichlorosilane; ethyltrichlorosilane; propyltrichlorosilane; and mixtures thereof.

31 . The process of claim 17 , wherein the ratio of gas volume in standard cubic metres used in total in steps a) and b) to the amount of the liquid raw material used in kilograms is from 0.1 to 100 m 3 (STP)/kg.

32 . The process of claim 31 , wherein the gas used in step a) and/or b) comprises oxygen.

33 . The process of claim 32 , wherein the liquid raw material is preheated to a temperature of 50 to 500° C. prior to performance of step a).

34 . The process of claim 32 , wherein the liquid raw material used in step a), prior to performance of step a), has a pressure of at least 1.5 bar and the gas mixture obtained in step b) has a pressure of not more than 1.2 bar.

35 . The process of claim 34 , wherein the metal oxide comprises at least one of the elements Al, Ce, Fe, Mg, In, Ti, Sn, Y, Zn and/or Zr as the metal component.

Assignees

• Evonik Operations Gmbh

Inventors

• Erz Joachim
• Severin Claudia
• Cornelius Maximilian

Classifications

• C01B33/183 Primary

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

• C01G23/07 Primary

  Producing by vapour phase processes, e.g. halide oxidation · CPC title

• C01B13/34

  by oxidation or hydrolysis of sprayed or atomised solutions · CPC title

• C01P2004/60

  Particles characterised by their size · CPC title