Compositional Analysis Of A Gas Or Gas Stream In A Chemical Reactor and Method For Preparing Chlorosilanes In A Fluidized Bed Reactor

Patent metadata

Field	Value
Publication number	US-2016131584-A1
Application number	US-201414899147-A
Country	US
Kind code	A1
Filing date	Jun 17, 2014
Priority date	Jul 2, 2013
Publication date	May 12, 2016
Grant date	—

Abstract

The composition of a gas or gas stream containing AlCl 3 in a chemical reactor is measured by removing AlCl 3 from the gas and analyzing the gas by gas chromatography or spectroscopy. Chlorosilanes may be prepared in a fluidized bed reactor having a reactor height H0, in which supplied HCl reacts with silicon, wherein a temperature profile in the fluidized bed reactor is greater than S1(H/H0)=(a1−b1)*(1/(1+exp(−c1((H/H0)−d1))))+b1 and less than S2(H/H0)=(a2−b2)*(1/(1+exp(−c2((H/H0)−d2))))+b2, where a1=100° C., a2=300° C., b1=300° C., b2=400° C., c1=50, c2=20, d1=0.2, and d2=0.8.

First claim

1 .- 15 . (canceled)

16 . A method for analyzing the composition of a gas or gas stream comprising AlCl 3 in a chemical reactor, comprising removing AlCl 3 from the gas and subsequent analysis of the gas by means of gas chromatography or spectroscopy.

17 . The method of claim 16 , wherein the gas or gas stream is one arising in the synthesis of chlorosilanes or organochlorosilanes.

18 . The method of claim 16 , wherein the gas or gas stream is one produced in a chemical operation using metallurgical silicon.

19 . The method of claim 16 , wherein removing AlCl 3 is accomplished by absorption with sodium chloride.

20 . The method of claim 16 , further comprising removing particulate solids as well as AlCl 3 .

21 . The method of claim 16 , wherein the gas is analyzed by Raman spectroscopy, gas chromatography or IR spectroscopy.

22 . The method of claim 16 , wherein the analysis of the gas or gas stream determines the concentrations of HCl, N 2 , H 2 , chlorosilanes and organochlorosilanes in the gas.

23 . (New The method of claim 16 , wherein the data obtained from analysis of the gas is used to control the chemical reactor.

24 . The method of claim 23 , wherein the reactor is a fluidized bed reactor in which TCS is prepared by reaction of metallurgical silicon with HCl.

25 . The method of claim 24 , wherein the analysis of the gas is used to change one or more reactor parameters or operating parameters so as to optimize one or more variables selected from the group consisting of yield, TCS selectivity, HCl conversion rate, and space-time yield.

26 . The method of claim 16 , wherein the analysis of the gas is used to modify temperatures in the reactor and temperature profile as a function of a reactor height.

27 . The method of claim 26 , wherein the temperature profile in the fluidized bed reactor having a reactor height H0, in which HCl reacts with silicon to form chlorosilanes is greater than S1(H/H0)=(a1−b1)*(1/(1+exp(−c1((H/H0)−d1))))+b1 and less than S2(H/H0)=(a2−b2)*(1/(1+exp(−c2((H/H0)−d2))))+b2, where a1=100° C., a2=300° C., b1=300° C., b2=400° C., c1=50, c2=20, d1=0.2, and d2=0.8.

28 . The method of 24, wherein the analysis of the gas determines a time for discharge of catalyst material.

29 . A method for preparing chlorosilanes in a fluidized bed reactor having a reactor height H0, in which HCl reacts with silicon, comprising establishing a temperature profile in the fluidized bed reactor which is greater than S1(H/H0)=(a1−b1)*(1/(1+exp(−c1((H/H0)−d1))))+b1 and less than S2(H/H0)=(a2−b2)*(1/(1+exp(−c2((H/H0)−d2))))+b2, where a1=100° C., a2=300° C., b1=300° C., b2=400° C., c1=50, c2=20, d1=0.2, and d2=0.8.

30 . The method of claim 29 , further comprising removing AlCl 3 from a product gas stream and analyzing the product gas stream by gas chromatography or spectroscopy to obtain data on the composition of the product gas stream, and adjusting the temperature profile of the reactor from the data to optimize production of a desired chlorosilane product.

Assignees

• Wacker Chemie Ag

Inventors

• Goebel Thorsten
• Haeckl Walter
• Muenzer Wolfgang
• Paetzold Uwe
• Sofina Natalia

Classifications

• G01N21/65 Primary

  Raman scattering · CPC title

• G01N2201/08

  Optical fibres; light guides · CPC title

• G01N30/86

  Signal analysis · CPC title

• B01D2251/60

  Inorganic bases or salts · CPC title

• C01B33/10742

  prepared by hydrochlorination of silicon or of a silicon-containing material · CPC title