WO2010028878A1 - Wirbelschichtreaktor, dessen verwendung und ein verfahren zur energieautarken hydrierung von chlorsilanen - Google Patents
Wirbelschichtreaktor, dessen verwendung und ein verfahren zur energieautarken hydrierung von chlorsilanen Download PDFInfo
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- WO2010028878A1 WO2010028878A1 PCT/EP2009/058790 EP2009058790W WO2010028878A1 WO 2010028878 A1 WO2010028878 A1 WO 2010028878A1 EP 2009058790 W EP2009058790 W EP 2009058790W WO 2010028878 A1 WO2010028878 A1 WO 2010028878A1
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B33/00—Silicon; Compounds thereof
- C01B33/08—Compounds containing halogen
- C01B33/107—Halogenated silanes
- C01B33/1071—Tetrachloride, trichlorosilane or silicochloroform, dichlorosilane, monochlorosilane or mixtures thereof
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
- B01J8/18—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with fluidised particles
- B01J8/24—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with fluidised particles according to "fluidised-bed" technique
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J19/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
- B01J19/02—Apparatus characterised by being constructed of material selected for its chemically-resistant properties
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
- B01J8/005—Separating solid material from the gas/liquid stream
- B01J8/006—Separating solid material from the gas/liquid stream by filtration
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
- B01J8/18—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with fluidised particles
- B01J8/1809—Controlling processes
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J8/00—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes
- B01J8/18—Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes with fluidised particles
- B01J8/1836—Heating and cooling the reactor
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B33/00—Silicon; Compounds thereof
- C01B33/02—Silicon
- C01B33/021—Preparation
- C01B33/027—Preparation by decomposition or reduction of gaseous or vaporised silicon compounds other than silica or silica-containing material
- C01B33/029—Preparation by decomposition or reduction of gaseous or vaporised silicon compounds other than silica or silica-containing material by decomposition of monosilane
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B33/00—Silicon; Compounds thereof
- C01B33/08—Compounds containing halogen
- C01B33/107—Halogenated silanes
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J2208/00—Processes carried out in the presence of solid particles; Reactors therefor
- B01J2208/00008—Controlling the process
- B01J2208/00017—Controlling the temperature
- B01J2208/00026—Controlling or regulating the heat exchange system
- B01J2208/00035—Controlling or regulating the heat exchange system involving measured parameters
- B01J2208/00044—Temperature measurement
- B01J2208/00061—Temperature measurement of the reactants
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J2208/00—Processes carried out in the presence of solid particles; Reactors therefor
- B01J2208/00008—Controlling the process
- B01J2208/00017—Controlling the temperature
- B01J2208/00026—Controlling or regulating the heat exchange system
- B01J2208/00035—Controlling or regulating the heat exchange system involving measured parameters
- B01J2208/00079—Fluid level measurement
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J2208/00—Processes carried out in the presence of solid particles; Reactors therefor
- B01J2208/00008—Controlling the process
- B01J2208/00017—Controlling the temperature
- B01J2208/00106—Controlling the temperature by indirect heat exchange
- B01J2208/00115—Controlling the temperature by indirect heat exchange with heat exchange elements inside the bed of solid particles
- B01J2208/00132—Tubes
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J2208/00—Processes carried out in the presence of solid particles; Reactors therefor
- B01J2208/00008—Controlling the process
- B01J2208/00017—Controlling the temperature
- B01J2208/00106—Controlling the temperature by indirect heat exchange
- B01J2208/00168—Controlling the temperature by indirect heat exchange with heat exchange elements outside the bed of solid particles
- B01J2208/00212—Plates; Jackets; Cylinders
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J2208/00—Processes carried out in the presence of solid particles; Reactors therefor
- B01J2208/00008—Controlling the process
- B01J2208/00017—Controlling the temperature
- B01J2208/00106—Controlling the temperature by indirect heat exchange
- B01J2208/00265—Part of all of the reactants being heated or cooled outside the reactor while recycling
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/10—Process efficiency
- Y02P20/129—Energy recovery, e.g. by cogeneration, H2recovery or pressure recovery turbines
Definitions
- the present invention relates to a device, its use and a method for the substantially energy self-sufficient continuous production of chlorosilanes, in particular for the production of trichlorosilane as an intermediate for the production of high-purity silicon.
- Trichlorosilane especially in pure form, is today an important starting material u. a. for the production of high-purity silicon, for example for the production of chips or solar cells (WO 02/48034, EP 0 921 098).
- catalysts are already present in metallurgical silicon, for example in oxidic or metallic form, as silicides or in other metallurgical phases. Also catalysts can be added in said reactions in metallic or alloyed or salt-like form be or be present.
- the wall or surface material of the reactor used can also exert a catalytic influence on the reaction (inter alia B. Kanner and KM Lewis “Commercial Production of Silanes by Direct Synthesis", pages 1-66, Studies in Organic Chemistry 49, Catalyzed Lewis and DG Rethwisch, 1993, Elsevier Science Publishers, H. Samori et al., "Effects of trace elements in metallurgical silicones on trichlorosilane synthesis reaction", Silicon for the chemical industry III, Sandefjord, Norway, June 18-20, 1996, pages 157-167; J.
- silicon, silicon tetrachloride and hydrogen or silicon, silicon tetrachloride, hydrogen and hydrogen chloride as Eduktkomponenten under reaction conditions of 20 to 42 bar and 400 to 800 0 C to meter into the reactor to start the reaction and keep it running. It is also necessary, in the event of an interruption in operation in a stand-by mode, to maintain the educts or educt feed at the required operating pressure and temperature in order to start up again without long heating times or to continue operation.
- the object was to provide a further, most economical possibility for large-scale, continuous conversion of silicon (Si), silicon tetrachloride (STC, SiCl 4 ), hydrogen (H 2 ) and optionally hydrogen chloride (HCl) and optionally further components to the abovementioned Mitigate problems.
- a particular concern of the present invention was to provide trichlorosilane (TCS, HSiCb) as energy and cost saving as possible for a composite system for producing high-purity silicon, chlorine or organosilanes and organosiloxanes and fumed silica.
- reaction of particulate Si, chlorosilanes, in particular SiCl 4 , and H 2 and optionally in the presence of at least one catalyst at a pressure of 25 to 55 bar and a temperature of 450 to 650 0 C in a can carry out particularly energy and thus cost-saving manner, if in the implementation of the present method gas-fired burner, in particular natural gas burner, used for heating the STC stream and for the startup process of the reactor and for regulation or control.
- gas-fired burner in particular natural gas burner
- the necessary reaction energy can be advantageously supplied via the reactor heating in a simple and particularly economical manner.
- excess heat can be dissipated via the reactor temperature control and used to advantage by means of a heat exchanger, for example for preheating educt gases.
- HCl and / or CI 2 can be deliberately introduced or metered into the fluidized bed reactor in order to regulate an energy input for starting up or for maintaining the present reaction or reactions in an advantageous energy-saving manner.
- At least one catalyst when carrying out the present process.
- the present process as well as the system developed therefor, in particular the new fluidized bed plant, and such a plant can advantageously be integrated in so-called composite systems for the production of chlorosilanes, silanes, organosilanes, organosiloxanes, pyrogenic and precipitated silicic acid and solar silicon particularly advantageously on a large industrial scale carry out or operate economical, continuous driving.
- FIG. 1 shows a preferred embodiment of the fluidized-bed reactor according to the invention.
- a reactor jacket (1.1) having an internal diameter of 100 mm to 2000 mm and a height of 5 m to 25 m, particularly preferably of 200 mm to 1500 mm internal diameter and a height of 10 m to 20 m.
- Figure 2 wherein the substantially STC-containing chlorosilane stream (B) of about 20 0 C, ie ambient temperature, to a temperature of 650 0 C at a pressure of 25 to 55 bar can be heated and the unit (2) on a chlorosilane Feed (B), in particular from STC, by means of pump (2.1), a gas-fired heat exchanger boiler (2.2), together with gas burner (2.3), at least one expansion vessel with condensate return / buffer tank (2.4) including condensate control (2.5) and at least one metering unit (2.6 ), wherein unit (2.1) is connected via line (2.1.1) to unit (2.2), further line (2.2.1) connects the heat exchanger (2.2) on the output side to unit (2.4), any condensate occurring here and / or or vaporous STC (recycle mode) via a line (2.4.1) or (2.4.2) the line (2.1.1) can be fed back and heated vaporous chlorosilane or STC (B *) from the unit (
- FIG. 2 shows a preferred embodiment of a gas-fired heater for chlorosilanes for starting up and specifically applying a reactor uniformly to a temperature of 650 ° C. at a pressure of up to 55 bar, in particular for heating a substantially STC-containing chlorosilane feed to pressurize a reactor present fluidized bed reactor.
- the chlorosilane heater for starting up and pressurizing the fluidized bed unit (1) or (1.4) with chlorosilane (B *), in particular with a STC-containing chlorosilane stream, but can also be used as in the not yet published parallel application PCT / EP2008 / 053079 entitled "Method for the sliding temperature control of chemical substances with defined inlet and outlet temperatures in a heater and device for carrying out the method" described or carried out.
- the fluidized-bed reactor (1) or (1.1) is advantageously acted upon via a fluidiseboden for the supply of (B or B *) (1.4), wherein the fluidized bed and the filling level of component (A) in the reactor (1.1) set in motion and the average residence time of the gaseous product mixture in the reactor is substantially controlled.
- the fluid dynamics in the reactor (1.1) can be advantageously further improved by the use of at least one sieve tray in the region above the feed (1.4) in the reactor or a sieve tray system, which may include beds and / or flow installations.
- a fluidized bed reactor (1) is equipped with at least one gas metering unit for H 2 (C) (1.5.4) and HCl and / or chlorine gas (D) (1.5.2) for supplying the feeds (1.5).
- C H 2
- D chlorine gas
- a heater such as (2.2) or (1.11) is suitably used a combustible gas (E), preferably natural gas.
- E combustible gas
- the waste heat from the combustion chamber unit (2.2), discharged via (2.2.2), can advantageously be used for preheating gas streams (F) and / or by means of heat exchangers (1.5.5) for preheating (C) and / or (D) Gas flows are used to advantage.
- a fluidized-bed reactor (1) according to the invention may advantageously comprise a dust separation (1.7), the accumulation of waste being essentially based on filtration for the chlorosilane-containing product mixture obtained in the fluidized-bed reactor and discharged at the top of the reactor.
- a separation unit (1.8) is suitably provided in the fluidized bed reactor (1) according to the invention, the stream (H) being obtained as condensate and the stream (G) being removed in gaseous form. Uncondensed chlorosilanes can advantageously be recycled together with the hydrogen into the (hydher) reactor (1.1).
- FIG. 1 The plant parts of the fluidized bed reactor according to the invention, cf. ia FIG. 1, including chlorosilane or STC heaters, cf.
- Figure 2 which are in contact with educt, reaction or product streams, can be advantageous, for example - but not exclusively - be carried out by means of high heat resistant black steels such as 1.7380, or 1.5415, but preferably in the higher temperature range of stainless steel alloys of the series 1.4306, 1.4404, 1.4571 or 1.4876H.
- the present invention likewise provides a process for the continuous large-scale production of a product stream comprising trichlorosilane (TCS) by reacting essentially silicon (Si) (A), chlorosilanes, in particular silicon tetrachloride (STC), (B) and hydrogen (H 2 ) ( C) and optionally hydrogen chloride gas (HCl) and / or chlorine gas (Cl 2 ) or a mixture of hydrogen chloride and chlorine gas (D) at a pressure of 25 to 55 bar and a temperature of 450 to 650 0 C, preferably 35 to 45 bar and 550 to 620 ° C., in particular 38 to 42 bar and 580 to 610 ° C., and optionally in the presence of at least one catalyst, preferably based on at least one transition metal element, particularly preferably at least one of the series Fe, Co, Ni, Cu, Ta, W, such as FeCl 2 , CuCl, CuCl 2 and / or the corresponding metal silicides, in particular a
- a fluidized bed reactor according to any one of claims 1 to 9 to 1/8 to 3/4 of its reaction space with particulate silicon (A) is applied, wherein the component (A) may optionally be admixed with catalyst,
- H 2 (C) preferably 1 to 5 mol of H 2 (C), particularly preferably 1.1 to 2 mol of H 2 , are employed per mol of SiCl 4 (B).
- HCl (D) per mole of H 2 , preferably 0.001 to 0.7 mol of HCl, particularly preferably 0.01 to 0.5 mol of HCl more preferably 0.1 to 0.4 moles of HCl, especially 0.2 to 0.3 moles of HCl.
- a gas mixture of HCl and Cl 2 in a molar ratio HCl to Cl 2 of 0 to 1 to 1 to 0, preferably 0.01 to 0.99 to 0.99 to 0.01 deploy.
- the process according to the invention advantageously provides for a mean residence time of the gas or vapor mixture in the reactor of 0.1 to 120 seconds, preferably 0.5 to 100 seconds, more preferably 1 to 60 seconds, most preferably 3 to 30 seconds, especially 5 to 20 seconds.
- a mean residence time of the gas or vapor mixture in the reactor of 0.1 to 120 seconds, preferably 0.5 to 100 seconds, more preferably 1 to 60 seconds, most preferably 3 to 30 seconds, especially 5 to 20 seconds.
- the reaction temperature for the reaction in the reactor interior is monitored and controlled at a constant hydrogen / STC ratio by metering HCl and / or CI 2 (D) and / or the reaction temperature for the reaction in the reactor (1.1) via the units (1.2) and (1.3) using the medium (F) and the units (1.9) or (1.11) controlled or additionally regulated.
- the medium (F) for example-but not exclusively-air or an inert gas such as nitrogen or a noble gas such as argon may be used.
- silicon (A) is advantageously a metallurgical silicon having a mean particle size of from 10 to 3000 .mu.m, preferably from 50 to 2000 .mu.m, more preferably from 80 to 1500 .mu.m, very particularly preferably from 100 to 1000 ⁇ m, in particular 120 to 500 ⁇ m.
- the silicon (A) used here preferably has a purity greater than or equal to 80%, particularly preferably greater than or equal to 90%, in particular greater than or equal to 98%.
- At least one catalyst may advantageously be mixed with the silicon (A) by intensively mixing the silicon and the catalyst system, in particular by previously grinding the silicon and the catalyst together.
- the process according to the invention is carried out as follows:
- the reactor and the educt or product leading lines of the system are usually dried and rendered inert prior to startup, for example, by flushing the system with a preheated inert gas, such as argon or nitrogen until at the outlet of the proportion of oxygen tends to zero.
- a preheated inert gas such as argon or nitrogen
- the fluidized-bed reactor (1) is preceded by a unit (2), ie a gas-fired chlorosilane heater with circulation, for the start-up and subsequent uniform and continuous application of a heated reactant stream (B *), in which the starting material stream comprising B) of about 20 0 C to a temperature of 650 0 C and a pressure of 25 to 55 bar can be heated and the unit (2) in addition to control units and pressure-resistant lines substantially on a sg feed pump (2.1), on a gas-fired Heat exchanger boiler (2.2) with gas burner (2.3) and expansion vessel with condensate return (2.4) is based, with the hot flue gases in the combustion boiler flow around at least one pressure-resistant line, which serves to guide the chlorosilane or STC stream (B).
- a unit (2) ie a gas-fired chlorosilane heater with circulation, for the start-up and subsequent uniform and continuous application of a heated reactant stream (B *), in which the starting material stream comprising B) of about 20 0
- this unit consists of a suitable arrangement for a recycle mode for a uniform heating of the chlorosilane or STC stream, cf.
- the SiCI 4 which is suitably taken from a tank, by means of a piston diaphragm pump (2.1) are compressed about 40 bar. Via line (2.1.1), the SiCI 4 can thus enter the first heating coil sections of the natural gas-fired heater (2.2). Above this is suitably a level-controlled expansion vessel, which recirculates a resulting chlorosilane or STC liquid phase back into the chlorosilane or STC stream of the line (2.1.1) via the control unit (2.5) adapted to the prevailing pressure. leads.
- the reactor (1.1 ) From the gas space of the expansion vessel can be deliberately well-heated, vaporized chlorosilane or STC (B *) removed and as feed via the regulator unit (2.6) and the line (2.6.1) and the chlorosilane feed (1.4) the reactor (1.1 ) are advantageously supplied in a well-metered, preferably continuous volume flow.
- the buffer container (2.4) is also advantageous to compensate for pressure fluctuations and to provide the superheated chlorosilane or SiCI 4 temperature and pressure controlled for the continuous operation of the fluidized bed reactor (1).
- a chlorosilane stream in particular a STC stream obtained in a parallel or subsequent process, at least partially as feed stream (B) for the present chlorosilane heater advantageous.
- the boiler and buffer boiler of the chlorosilane heater and the associated lines for guiding chlorosilanes, especially of tetrachlorosilane, are usually made of heat-resistant black steels such as 1.7380, or 1.5415, but preferably in the higher temperature range of stainless steel alloys of the series 1.4306, 1.4404, 1.4571 or 1.4876H ,
- Such a heating device for chlorosilanes can be used in a particularly advantageous manner in a plant for the production of trichlorosilane or of particularly pure polycrystalline silicon.
- the use of such a gas-fired chlorosilane heater unit makes it possible in a particularly economical manner to save costly electrical heating of the chlorosilane or STC phase; This concerns both the acquisition and in particular the high operating costs of an electrically operated heater.
- the heating system directly fired with natural gas or hot gases can react more quickly to load changes, as long-lasting heating and afterheating effects are eliminated.
- the hot exhaust gases can also be performed several times over the heater to achieve further savings in operating costs.
- interruption of operation or termination of the reaction can be switched to a circulation operation, which makes it possible to keep the boiler or the heater on standby without loss of time for long heating times.
- a chlorosilane or STC stream (B *) heated in this way predominantly to supercritical conditions is advantageously metered into the fluidized-bed reactor (1), the reactor (1.1) being filled with ground silicon powder (A), preferably to 1/8 to 3 A of the reactor volume, particularly preferably 1/4 to 2/3, in particular 1/3 to 14, and that in the targeted application to the heated chlorosilane fluid swirled (also called fluidized bed or fluidized bed).
- the reaction generally takes place in the temperature range between 400 ° and 650 ° and a pressure of 25 to 55 bar.
- the inventive Reactor advantageously has a double jacket with internally welded ribs. These increase the heat transfer surface and at the same time ensure a guided flow of the medium.
- Reactors with a larger diameter may additionally contain suitable internals, which are also provided with ribs and through which the gas flows.
- This gas can be advantageously by a gas burner, see. (1.11), to any desired temperature. This makes it possible to heat the reactor (1.1) during start-up very evenly and gently to the required operating temperature. This can be accomplished according to the invention in a much more economical way than with an electric heater.
- the hydrogenation reaction is started by targeted addition or metering of hydrogen and optionally HCl and / or CI2 gas in the silicon bed with further energy supply medium heat transfer medium (F), which is heated by gas firing.
- the exothermic Hydrochloherre force of the silicon can be started.
- the addition of HCl can be purposefully increased until a temperature rise in the reactor is observed.
- the burner output can usually be withdrawn after the reaction has started and the reactor temperature can be switched from heating to cooling mode. Cooling can ensure that local overheating does not damage the reactor material.
- the cooling in particular in the space above the fluidized bed in the interior of the reactor, a back-reaction to STC can be advantageously reduced.
- the reaction resulting product mixture can be removed overhead of the reactor and suitably be freed by means of dust filter substantially of Si and possibly catalyst dust.
- the collected dust (J) can be recycled as a supplement via component (A). Subsequently, the product stream is suitably cooled to yield gas phase and TCS / STC liquid phase (H).
- the gas phase (G) can advantageously be recycled again via a separate feed, preferably in the lower part of the reactor.
- the separation of the product stream (H) in TCS and recyclable STC can, for example, by a Distillation take place.
- the proportion of silicon or silicon consumed in the product stream above the top of the reactor is suitably metered into the reactor via the solids feed (1.6.).
- a device according to the invention also referred to below as fluidized bed stage for short
- a composite system for producing chlorine or organosilanes, fumed silica and / or high-purity silicon for solar and electronic applications is particularly advantageous to use.
- the present invention also relates to the use of a device according to the invention (hereinafter also referred to as fluidized bed step) in a composite system for the known production of silanes and organosiloxanes, in particular chlorosilanes or organosilanes, such as monosilane, monochlorosilane, dichlorosilane, trichlorosilane, Silicon tetrachloride, vinyltrichlorosilane, substituted or unsubstituted C 3-18 -alkylchlorosilanes, such as 3-chloropropyltrichlorosilane, propyltrichlorosilane, trimethoxysilane, thethoxysilane, tetramethoxysilane, tetraethoxysilane, vinyltrialkoxysilane, substituted or unsubstituted C 3-18 -alkylalkoxysilanes, such as propyltrialkoxysi
- methoxy and ethoxy is, to name just a few, and derived products thereof, wherein chlorosilane streams, in particular STC-containing streams, at least partially recycled into the process stages for the production of fumed silica and for the production of chlorosilanes in the fluidized bed.
- chlorosilane streams in particular STC-containing streams
- monosilane can be used advantageously for the production of polycrystalline silicon (solar grade) by thermal decomposition of monosilane. Furthermore, it is possible to advantageously recycle the hydrogen produced in the thermal decomposition of the monosilane in the context of the composite system into the fluidized bed stage according to the invention.
- a device and a substantially energy self-sufficient process for the production of trichlorosilane starting from metallurgical silicon, silicon tetrachloride and hydrogen and optionally HCl and / or CI2 and optionally in the presence of a catalyst in a particularly economical manner with high yield and gentle driving for the Material of the reactor provided and particularly advantageous - as indicated above - are used.
- FIGS. 1 and 2 are identical Legend to FIGS. 1 and 2:
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Abstract
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Priority Applications (6)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CA2735874A CA2735874A1 (en) | 2008-09-10 | 2009-07-10 | Fluidized bed reactor, the use thereof, and a method for the energy-independent hydrogenation of chlorosilanes |
CN2009801355997A CN102149457A (zh) | 2008-09-10 | 2009-07-10 | 能量自给自足的氯硅烷加氢用的硫化床反应器、其应用及方法 |
UAA201104318A UA101400C2 (ru) | 2008-09-10 | 2009-07-10 | Реактор с псевдоожиженным слоем, его применение и способ энергонезависимого гидрирования хлорсиланов |
EP09780408.2A EP2321041B1 (de) | 2008-09-10 | 2009-07-10 | Wirbelschichtreaktor, dessen verwendung und ein verfahren zur energieautarken hydrierung von chlorsilanen |
US13/062,431 US20110229398A1 (en) | 2008-09-10 | 2009-07-10 | Fluidized bed reactor, the use thereof, and a method for the energy-independent hydrogenation of chlorosilanes |
JP2011526433A JP2012501949A (ja) | 2008-09-10 | 2009-07-10 | 流動層反応器、その使用及びクロロシランのエネルギー自立型の水素化方法 |
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DE102008041974.5 | 2008-09-10 | ||
DE102008041974A DE102008041974A1 (de) | 2008-09-10 | 2008-09-10 | Vorrichtung, deren Verwendung und ein Verfahren zur energieautarken Hydrierung von Chlorsilanen |
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US (1) | US20110229398A1 (de) |
EP (1) | EP2321041B1 (de) |
JP (1) | JP2012501949A (de) |
KR (1) | KR20110067093A (de) |
CN (1) | CN102149457A (de) |
CA (1) | CA2735874A1 (de) |
DE (1) | DE102008041974A1 (de) |
RU (1) | RU2011113636A (de) |
UA (1) | UA101400C2 (de) |
WO (1) | WO2010028878A1 (de) |
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WO2019068335A1 (de) | 2017-10-05 | 2019-04-11 | Wacker Chemie Ag | Verfahren zur herstellung von chlorsilanen |
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WO2019201439A1 (de) | 2018-04-18 | 2019-10-24 | Wacker Chemie Ag | Verfahren zur herstellung von chlorsilanen |
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WO2020125982A1 (de) | 2018-12-19 | 2020-06-25 | Wacker Chemie Ag | Verfahren zur herstellung von chlorsilanen |
WO2020125944A1 (de) | 2018-12-18 | 2020-06-25 | Wacker Chemie Ag | Verfahren zur herstellung von chlorsilanen |
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WO2019068336A1 (de) * | 2017-10-05 | 2019-04-11 | Wacker Chemie Ag | Verfahren zur herstellung von chlorsilanen unter verwendung eines katalysators ausgewählt aus der gruppe co, mo, w |
TWI786226B (zh) * | 2017-11-20 | 2022-12-11 | 日商德山股份有限公司 | 流體化床式反應裝置及三氯矽烷的製造方法 |
WO2019098348A1 (ja) * | 2017-11-20 | 2019-05-23 | 株式会社トクヤマ | 流動床方式反応装置 |
US20220212938A1 (en) * | 2019-04-29 | 2022-07-07 | Wacker Chemie Ag | Process for producing trichlorosilane with structure-optimised silicon particles |
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US20130142722A1 (en) * | 2010-08-13 | 2013-06-06 | Elkem As | Method for production of trichlorosilane and silicon for use in the production of trichlorosilane |
US9388051B2 (en) * | 2010-08-13 | 2016-07-12 | Elkem As | Method for production of trichlorosilane and silicon for use in the production of trichlorosilane |
WO2012123159A1 (de) * | 2011-03-16 | 2012-09-20 | Evonik Degussa Gmbh | Verbundverfahren zur herstellung von wasserstoffhaltigen chlorsilanen |
EP3858788A1 (de) | 2017-10-05 | 2021-08-04 | Wacker Chemie AG | Verfahren zur herstellung von chlorsilanen |
WO2019068335A1 (de) | 2017-10-05 | 2019-04-11 | Wacker Chemie Ag | Verfahren zur herstellung von chlorsilanen |
US11643330B2 (en) | 2017-10-05 | 2023-05-09 | Wacker Chemie Ag | Method for producing chlorosilanes |
WO2019154502A1 (de) | 2018-02-08 | 2019-08-15 | Wacker Chemie Ag | Verfahren zur klassifizierung von metallurgischem silicium |
US11691884B2 (en) | 2018-02-08 | 2023-07-04 | Wacker Chemie Ag | Method of classifying metallurgical silicon |
WO2019201439A1 (de) | 2018-04-18 | 2019-10-24 | Wacker Chemie Ag | Verfahren zur herstellung von chlorsilanen |
US11845667B2 (en) | 2018-04-18 | 2023-12-19 | Wacker Chemie Ag | Method for producing chlorosilanes |
WO2020125955A1 (de) | 2018-12-18 | 2020-06-25 | Wacker Chemie Ag | Verfahren zur herstellung von chlorsilanen |
WO2020125944A1 (de) | 2018-12-18 | 2020-06-25 | Wacker Chemie Ag | Verfahren zur herstellung von chlorsilanen |
WO2020125982A1 (de) | 2018-12-19 | 2020-06-25 | Wacker Chemie Ag | Verfahren zur herstellung von chlorsilanen |
Also Published As
Publication number | Publication date |
---|---|
UA101400C2 (ru) | 2013-03-25 |
EP2321041A1 (de) | 2011-05-18 |
KR20110067093A (ko) | 2011-06-21 |
CA2735874A1 (en) | 2010-03-18 |
CN102149457A (zh) | 2011-08-10 |
US20110229398A1 (en) | 2011-09-22 |
JP2012501949A (ja) | 2012-01-26 |
EP2321041B1 (de) | 2013-06-05 |
DE102008041974A1 (de) | 2010-03-11 |
RU2011113636A (ru) | 2012-10-20 |
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