CN116102018A - Method for separating hexachlorodisilane from polysilicon byproduct oligomeric chlorosilane - Google Patents

Method for separating hexachlorodisilane from polysilicon byproduct oligomeric chlorosilane Download PDF

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CN116102018A
CN116102018A CN202211413444.9A CN202211413444A CN116102018A CN 116102018 A CN116102018 A CN 116102018A CN 202211413444 A CN202211413444 A CN 202211413444A CN 116102018 A CN116102018 A CN 116102018A
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chlorosilane
oligomeric
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polysilicon
hexachlorodisilane
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CN116102018B (en
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张建树
赵文龙
张金利
郭瑞丽
彭文才
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Shihezi University
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    • C01B33/00—Silicon; Compounds thereof
    • C01B33/08—Compounds containing halogen
    • C01B33/107—Halogenated silanes
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Abstract

The invention provides a separation method of hexachlorodisilane in polysilicon byproduct oligomeric chlorosilane, which comprises the following steps: (1) Cracking reaction is carried out on the byproduct oligomeric chlorosilane of the polysilicon, wherein HCl gas is introduced to react with the byproduct oligomeric chlorosilane of the polysilicon, the reaction temperature is 90-120 ℃, the generated gas is condensed, and the residual liquid of the cracking reaction is collected; the polysilicon byproduct oligomeric chlorosilane comprises hexachlorodisilane, hexachlorodisiloxane, pentachlorodisilane, tetrachlorosilane and trichlorosilane; (2) And (3) crystallizing the residual liquid of the cracking reaction at a low temperature, and filtering to separate crystals. The method for combining the cracking reaction and the crystallization separation has low requirements on equipment, simple preparation process and low energy consumption, and separates Si from the polycrystalline silicon dimer 2 Cl 6 The effect is obviously promoted.

Description

Method for separating hexachlorodisilane from polysilicon byproduct oligomeric chlorosilane
Technical Field
The invention belongs to the technical field of polysilicon production processes, and particularly relates to a separation method of hexachlorodisilane in polysilicon byproduct oligomeric chlorosilane.
Background
The technology for producing polysilicon at home and abroad mainly uses an improved Siemens method, and in the process of producing polysilicon by the method, trichlorosilane (TCS) is synthesized and H is added into the trichlorosilane 2 Reduction section and STC hydrogenation sectionThere are different amounts of oligomeric chlorosilanes formed. Wherein the dimer is mainly Si 2 Cl 6 、Si 2 HCl 5 、Si 2 OCl 6 The method comprises the steps of carrying out a first treatment on the surface of the The high polymer contains Si 3 Cl 8 、Si 4 Cl 10 Cyclic siloxanes. Wherein Si in dimer 2 Cl 6 Is the most added value component, and is mainly used as a precursor for CVD or ALD to prepare amorphous silicon films and photochemical fiber raw materials. Has great development potential and practical value in the fields of semiconductors, photoelectric materials and the like.
The improved Siemens process is optimized to form a mature closed cycle production process, but how to effectively recycle the chlorosilane residual liquid generated in the process is always a difficult problem faced by a plurality of polysilicon enterprises. There are two main types of methods at present: one is a physical method, which mainly comprises a drying method, a filtering method, a crystallization method and an extraction method; the other type is chemical method, which mainly comprises hydrolysis method, combustion method and high-boiling-point substance catalytic cracking method. Chemical methods, represented by hydrolysis, are the most widely used processes at this stage.
At present, most of domestic polysilicon enterprises adopt a hydrolysis method to treat chlorosilane residual liquid in polysilicon production. The process mainly comprises filtering the generated chlorosilane raffinate to remove unreacted solid substances such as fine silica powder particles, and removing mixed AlCl by flocculation precipitation 3 And finally, distilling or rectifying the light component SiCl in the chlorosilane residual liquid for multiple times 4 (STC)、SiHCl 3 (TCS) and SiH 2 Cl 2 (DCS) and Si 2 Cl 6 、Si 2 OCl 6 And separating the main heavy components, rectifying and separating the light components, recycling the light components to the hydrogenation working section and the TCS hydrogenation reduction working section, and sending the heavy components to the hydrolysis working section by a recycling pump for hydrolysis treatment.
There are many reports on the hydrolysis solutions, and acidolysis solutions, alkaline hydrolysis solutions and alcoholysis solutions are mainly used according to the hydrolysis solutions. Si-Cl bonds in the various materials in the chlorosilane raffinate can easily form silanol (Si-OH) and HCl with water, silanol is generally unstable and will rapidly form siloxanes, i.e. -Si-O-Si-structured compounds. Thus, the light components undergo a condensation reaction simultaneously with hydrolysis to give complex cyclic or linear polysiloxanes. However, the direct discharge of hydrogen chloride gas and acidic wastewater produced by hydrolysis is harmful to the environment. Hydrolysis in alkaline solution can inhibit release of hydrochloric acid and neutralize acidity of wastewater, but hydrolysis-based process does not avoid waste of silicon resources.
The catalytic cracking method for treating the oligomeric chlorosilane can realize the recycling of silicon resources, and is an ideal method for treating the oligomeric chlorosilane. In the method, under the condition of a catalyst, hydrogen chloride, chlorine and halogenated hydrocarbon are used as cracking reagents to break Si-Si bonds in oligomeric chlorosilane, so that chlorosilane monomers are produced and recycled. Similar catalytic cracking processes have been used to treat high boiling residues generated during the synthesis of Methylchlorosilanes (MCSs). Further studies have found that the presence of a catalyst in a hydrogen chloride atmosphere greatly promotes the cleavage of HBR. Thus, the catalytic cracking process greatly increases the yield of MCSs. The structure of chlorosilanes was found to have a large effect on cleavage of HBR. It has also been found that halogen-substituted disilanes cleave Si-Si bonds in the presence of ammonium halides, the ethyl derivative reacting with ammonium chloride in the order Si 2 Cl 6 ≈EtSi 2 Cl 5 ＞Et 2 Si 2 Cl 4 . Although there is much research on organosilicon cleavage HBR, there is less treatment of polysilicon cleavage HBR.
Si 2 Cl 6 Is the most valuable component in the chlorosilane raffinate, and the preparation method mainly comprises the synthesis method and the high-polychlorosilane Si generated in the production of polysilicon n Cl 2n+2 (n is more than or equal to 3) preparing Si by catalytic pyrolysis 2 Cl 6 And Si generated for each section in the production of polysilicon 2 Cl 6 And (5) separating. The synthesis reaction has low target yield, multiple byproducts and great difficulty in subsequent separation and purification, so that the method is characterized in that Si 2 Cl 6 Rarely used in preparation.
The initial idea of the extraction method is to recycle the chlorosilane slag slurry generated in the production process of the organic silicon monomer. Adding extractant into a reaction kettle filled with chlorosilane, and heating the reactor to uniformly mix the extractantFinally, the mixture is sent into a dryer for drying. And rectifying the gas phase substance after the drying is finished for multiple times to obtain chlorosilane. Patent CN 108358209A selects C 12 -C 16 Is used as an extractant to recycle and treat chlorosilane raffinate. The electronic grade hexachlorodisilane is obtained by extracting and purifying the electronic grade hexachlorodisilane by adopting a low-density extractant A and a high-density extractant B, wherein the hexachlorodisilane comprises 3N grade, 4N grade and 5N grade.
The rectification method is also a common method for purifying chlorosilane from the chlorosilane residual liquid. Patent CN 103101914A proposes a process and a device for recycling residual liquid and residue of intermittent chloro-silicane kang, and particularly aims at recycling hexachloro-disilane with extremely high value. The process mainly comprises a primary rectifying tower and a batch rectifying tower. Is suitable for treating cold-hydrogenated slag slurry, rectification residual liquid, rectification liquid in synthetic procedure and the like in the production of polysilicon, and can recover hexachlorodisilane with purity of more than 98 percent. Patent CN 106966397A also proposes a method for recovering hexachlorodisilane. The method comprises the steps of firstly, filtering polysilicon residual liquid to obtain filtrate and filter residues containing solid particles and metal polymer impurities; carrying out first rectification on the filtrate to remove impurities containing amorphous silicon and metal, thereby obtaining a first tower top rectification liquid; then rectifying the first tower top rectifying liquid for the second time to remove low-boiling-point substances containing trichlorosilane and silicon tetraoxide, thereby obtaining second tower bottom rectifying liquid; and rectifying the rectifying liquid of the second tower kettle for the third time to remove silicon tetrachloride and hexachlorodisiloxane, thereby obtaining the rectifying liquid of the third tower kettle mainly containing hexachlorodisilane.
Patent CN 105271246A proposes a method for preparing chlorodisilane from polysilicon by-product. The method separates aluminum trichloride from high-boiling residue liquid, and then selectively chlorinates hydrogen-containing chlorodisilane by a safe and efficient chlorination means to obtain a desired chlorodisilane mixture, and the mixture is separated by the existing rectification technology to obtain single-component chlorodisilane. But the separation system does not contain hexachlorodisiloxane.
Patent CN 108017060B proposes a purification method of industrial grade hexachlorodisilane, which comprises the steps of introducing industrial grade hexachlorodisilane into an exchange column filled with adsorption resin, and carrying out adsorption purification under the conditions of 50-65 ℃ and the flow rate of 0.22BV/h, wherein the product is the purified hexachlorodisilane product. The technical core is mainly the preparation of chelate resin.
The dimeric chlorosilane component in the polysilicon produced by the improved Siemens method is more complex and mainly contains Si 2 Cl 6 、Si 2 HCl 5 、Si 2 OCl 6 Also contains a certain amount of SiCl 4 、SiHCl 3 Boiling point is in the range of 30-150 ℃. Wherein Si is 2 Cl 6 With Si 2 OCl 6 The boiling points of (2) are very close, the rectification separation requires more column plate number, si 2 Cl 6 The yield of (2) is relatively low. By crystallization separation, si is contained in the system 2 HCl 5 、SiHCl 3 And hydrogen-containing chlorosilane, H atoms and Cl atoms interact, so that the crystallization temperature is as low as-40 ℃, which is unfavorable for industrial separation.
Disclosure of Invention
In order to solve the problems in the prior art, the invention provides a separation method of hexachlorodisilane in the byproduct oligomeric chlorosilane of polysilicon. The invention provides a method for Si by combining partial chlorosilane cleavage reaction and crystallization separation 2 Cl 6 With Si 2 OCl 6 The separation method comprises introducing hydrogen chloride gas to make Si 2 HCl 5 Decomposition of the hydrogen-containing chlorosilanes to SiCl 4 、SiHCl 3 、SiH 2 Cl 2 Returning monosilane with equal low boiling point to polysilicon system and residual Si 2 Cl 6 With Si 2 OCl 6 The disilane has no hydrogen-containing chlorosilane, so that the crystallization temperature can be obviously increased, and the crystallization separation is facilitated.
The invention provides a separation method of hexachlorodisilane in polysilicon byproduct oligomeric chlorosilane, which comprises the following steps:
(1) Cracking reaction is carried out on the byproduct oligomeric chlorosilane of the polysilicon, wherein HCl gas is introduced to react with the byproduct oligomeric chlorosilane of the polysilicon, the reaction temperature is 90-120 ℃, the generated gas is condensed, and the residual liquid of the cracking reaction is collected;
the polysilicon byproduct oligomeric chlorosilane comprises hexachlorodisilane, hexachlorodisiloxane, pentachlorodisilane, tetrachlorosilane and trichlorosilane;
(2) And (3) crystallizing the residual liquid of the cracking reaction at a low temperature, and filtering to separate crystals.
Preferably, in step (1), the reaction temperature is from 90 to 110 ℃, preferably 100 ℃.
Preferably, in step (1), the reaction time is from 15min to 90min, preferably from 30 to 60min, most preferably 30min.
Preferably, in the step (1), the HCl gas is introduced at a rate of 30mL/min.
Preferably, in step (1), the condensation temperature at which the gaseous product is collected by condensation is-10 ℃.
Preferably, in step (1), N is introduced before the cleavage reaction is carried out 2 To replace the air in the container.
Preferably, in step (2), the low temperature crystallization is carried out at a temperature of-10 ℃ to 20 ℃, preferably at a temperature of-15 ℃.
Preferably, in the step (2), stirring is performed at the time of low-temperature crystallization.
Preferably, in the step (2), filtration is performed by using a filter membrane having a pore size of 0.45. Mu.m.
Preferably, in the step (2), pentachlorodisilane is not contained in the crystal; preferably, the content of hexachlorodisilane in the crystal is 95.68-97.34% by weight.
Compared with the prior art, the invention has the beneficial effects that:
the invention makes byproduct dimeric chlorosilane in the polysilicon production process undergo the process of cracking reaction under the atmosphere of HCl, so that the dimeric chlorosilane contains hydrogen chlorosilane (Si) 2 HCl 5 ) The cracking reaction takes place, the remainder Si 2 Cl 6 And Si (Si) 2 OCl 6 Then through low temperature crystallization, si with higher bid value is separated from the Si 2 Cl 6 . Compared with the prior cracking method for treating chlorosilane, the cracking method only aims at the cracking of dimeric chlorosilaneReadily cleavable hydrogen-containing chlorosilanes (Si) 2 HCl 5 ) While retaining Si of relatively high value 2 Cl 6 And the cracking process only requires HCl gas without using a catalyst. Separation of Si from existing crystals 2 Cl 6 Compared with the method of the invention, the method leads Si to be cracked in HCl atmosphere 2 HCl 5 Decomposition of hydrochlorosilanes to SiCl 4 、SiHCl 3 、SiH 2 Cl 2 The low boiling monosilane returns to the polysilicon system. The mother solution does not contain hydrogen-containing chlorosilane, so that the hydrogen bonding action of H atoms and Cl is eliminated, and Si is facilitated 2 Cl 6 The crystallization temperature is greatly improved, and the crystallization temperature is at-10 ℃. The crystallization conditions are milder than direct crystallization.
In summary, the method for combining the cracking reaction and the crystallization separation has low requirements on equipment, simple preparation process and low energy consumption, and separates Si from the polycrystalline silicon dimer 2 Cl 6 The effect is obviously promoted.
Detailed Description
The following examples facilitate a better understanding of the present invention, but are not intended to limit the same. The experimental methods in the following examples are conventional methods unless otherwise specified. The test materials used in the examples described below, unless otherwise specified, were purchased from conventional Biochemical reagents. The quantitative tests in the following examples were all set up in triplicate and the results averaged.
The invention discloses a method for separating hexachlorodisilane from polysilicon byproduct oligomeric chlorosilane, which comprises the following steps:
(1) Cracking reaction is carried out on the byproduct oligomeric chlorosilane of the polysilicon, wherein HCl gas is introduced to react with the byproduct oligomeric chlorosilane of the polysilicon, the reaction temperature is 90-120 ℃, the generated gas is condensed, and the residual liquid of the cracking reaction is collected;
(2) And (3) crystallizing the residual liquid of the cracking reaction at low temperature, and filtering to separate crystals, wherein the main component of the crystals is hexachlorodisilane.
The polysilicon byproduct oligomeric chlorosilane comprises hexachlorodisilane (Si 2 Cl 6 ) Hexachlorodisiloxane (Si) 2 OCl 6 ) Pentachlorodisilane (Si) 2 HCl 5 ) Tetrachlorosilane (SiCl) 4 ) And trichlorosilane (SiHCl) 3 )。
According to some embodiments of the present application, in step (1), the reaction time is 15min to 90min.
The reaction temperature is selected to be 90-120 ℃ and the reaction time is selected to be 15-90 min because pentachlorodisilane can be completely cracked into SiCl when the reaction temperature is selected to be within the range 4 、SiHCl 3 、SiH 2 Cl 2 And monosilane products, while hexachlorodisilane is cleaved only in small amounts. More hexachlorodisilane is cracked at the reaction temperature higher than 120 ℃, and pentachlorodisilane cracking reaction is basically not generated at the temperature lower than 90 ℃. The reaction time is lower than 15min, the pentachlorodisilane cracking reaction is incomplete, and the hexachlorodisilane loss is more than 90min.
In some embodiments, in step (1), the reaction temperature is from 90 to 110 ℃ and the reaction time is from 30 to 60 minutes.
In some embodiments, in step (1), the reaction temperature is 100 ℃ and the reaction time is 30min. Under this condition, complete cleavage of pentachlorodisilane can be ensured, but less hexachlorodisilane is cleaved.
According to some embodiments of the present application, in step (1), the HCl gas is introduced at a rate of 30mL/min, above which or with liquid carried out by the gas stream.
According to some embodiments of the present application, in step (1), N is introduced before the cleavage reaction is performed 2 To replace the air in the container to prevent oxidation or flash-over.
According to some embodiments of the present application, in step (1), the generated gas comprises: siCl obtained by total cleavage of pentachlorodisilane in HCl atmosphere 4 、SiHCl 3 、SiH 2 Cl 2 Iso-monosilane products, including SiCl obtained by small amounts of cleavage of hexachlorodisilane in an HCl atmosphere (cleavage rate not exceeding 5.30%) 4 、SiHCl 3 、SiH 2 Cl 2 Iso-monosilane products and methods of making the same 4 ) And trichlorosilane (SiHCl) 3 )。
According to some embodiments of the present application, in step (1), the condensing temperature at which the gaseous product is collected by condensation is-10 ℃ to-15 ℃ to ensure complete condensation of the gaseous product into a liquid.
According to some embodiments of the present application, in step (2), the temperature of the crystallization is-10 ℃ to 20 ℃, preferably the temperature of the crystallization is-15 ℃.
According to some embodiments of the present application, in step (2), stirring during low temperature crystallization may accelerate Si 2 Cl 6 The crystallization is not required to be carried out at a stirring rate, and the liquid may be stirred uniformly as much as possible. For example, the Si in the liquid can be stirred at a speed of 100-250rpm for 3 hours 2 Cl 6 More completely crystallized.
According to some embodiments of the present application, in step (2), filtration is performed using a filter membrane having a pore size of 0.45 μm. The filter membrane with the pore diameter can be used for filtering Si in liquid 2 Cl 6 The crystal is filtered more completely, and Si is filtered 2 OCl 6 Remain in the filtrate.
According to some embodiments of the present application, in step (2), the filtrate obtained by filtration contains Si as the main component 2 OCl 6 。
By adopting the separation method, the hexachlorodisilane in the crystal has the weight percentage content of 95.68-97.34 percent and does not contain pentachlorodisilane.
Example 1
Oligomeric chlorosilane raw material liquid: contains 76.53% hexachlorodisilane (Si) 2 Cl 6 ) 7.55% hexachlorodisiloxane (Si) 2 OCl 6 ) 12.05% pentachlorodisilane (Si 2 HCl 5 ) 3.34% tetrachlorosilane (SiCl) 4 ) And 0.53% trichlorosilane (SiHCl) 3 ). The mass percentages are as above.
The invention discloses a method for separating hexachlorodisilane from polysilicon byproduct oligomeric chlorosilane, which comprises the following steps:
a three-necked round bottom flask dried to constant weight was taken and 77g (50 mL) of oligomeric chlorosilane was accurately weighedThe alkane feed solution was added thereto. And (3) magnetic stirring is well installed, the outlet of the flask is connected with a condenser, the reaction product is condensed and collected, and the temperature value of the condenser is adjusted to be-10.0 ℃ so as to ensure that the gas-phase product is completely condensed into liquid. Introducing N 2 And checking whether air leakage occurs, after air tightness is confirmed, setting heating temperature to 100deg.C, stirring rotation speed to 250rpm, and closing N 2 The total valve is switched to HCl gas, the pressure is regulated to normal pressure, and then the HCl flowmeter is regulated to 30mL/min. After 30min of reaction, closing the HCl gas cylinder valve to switch the three-way ball valve to N 2 Purging, heating and stirring are closed, cooling to normal temperature, and finally, the residual liquid of the cracking reaction is weighed, the weight of the residual liquid of the cracking reaction is 61.60g, and the composition of each substance in the residual liquid after the cracking reaction is analyzed by gas chromatography, wherein the composition is shown in the table 1.
Almost all pentachlorodisilane is cracked into SiCl in HCl atmosphere during the reaction 4 、SiHCl 3 、SiH 2 Cl 2 Isomonosilane product, siCl 4 、SiHCl 3 、SiH 2 Cl 2 And distilling the monosilane product out of the reaction system. Hexachlorodisilane is also partially cleaved to monosilane with a cleavage rate of 5.3%. While hexachlorodisiloxane undergoes little cleavage reaction. The residual liquid is mainly hexachlorodisilane (Si 2 Cl 6 ) Hexachlorodisiloxane (Si) 2 OCl 6 ) A small amount of dissolved SiCl 4 、SiHCl 3 。
The remaining solution after the cleavage reaction of the previous step was transferred to a crystallization reactor, the temperature was set at-15.+ -. 1 ℃ and stirred at 250rpm for 3 hours using a stirring device, and then transferred to a low temperature (-15 ℃) filtration device and rapidly filtered with a filter membrane having a pore size of 0.45. Mu.m. Thereby obtaining crystals and a first mother solution. The weight of the crystal is 34.65g, and the main component of the crystal is Si 2 Cl 6 The first mother liquor is mainly the rest Si 2 OCl 6 The composition of each substance in the crystals (measurement method: the crystals were analyzed by gas chromatography after melting at ordinary temperature) is shown in Table 1.
TABLE 1
Figure BDA0003939636190000061
Comparative example 1
The raw material liquid of the oligomeric chlorosilane contains 76.53 percent of hexachlorodisilane (Si 2 Cl 6 ) 7.55% hexachlorodisiloxane (Si) 2 OCl 6 ) 12.05% pentachlorodisilane (Si 2 HCl 5 ) 3.34% tetrachlorosilane (SiCl) 4 ) And 0.53% trichlorosilane (SiHCl) 3 ). The mass percentages are as above.
77g (50 mL) of the oligomeric chlorosilane stock solution was accurately weighed into a crystallization reactor, different crystallization temperatures were set, and stirred at 250rpm using a stirring device. Crystallization was completed after 3 hours at the set temperature. Crystallization at different temperatures was observed. When crystallization occurs in the mother liquor, the crystals and the mother liquor are transferred to a low temperature filtration device (the low temperature filtration temperature is the same as the crystallization temperature) and rapidly filtered with a filter membrane having a pore size of 0.45 μm. Thereby obtaining crystals and a first mother solution. The crystal is Si after the first purification 2 Cl 6 The first mother liquor is mainly the rest Si 2 OCl 6 。
When the crystallization temperature is-20 ℃ and-30 ℃, no solid phase crystallization occurs in the system. When the crystallization temperature was-40 ℃, solid-phase crystallization occurred in the system, and the weight of the crystals obtained by filtering the crystals with a filter membrane having a pore size of 0.45 μm was 30.48g. Crystallization at various temperatures and compositions of crystals are shown in Table 2.
TABLE 2
Figure BDA0003939636190000071
Example 2
The oligomeric chlorosilane feed composition was the same as in example 1.
77g of the oligomeric chlorosilane raw material liquid is accurately weighed and added into a three-neck round bottom flask to carry out cracking reaction. The cleavage reaction of the oligomeric chlorosilane was carried out in the same manner as in example 1, the cleavage reaction temperature was set to 60℃and the other reaction conditions were the same as in example 1. After the completion of the reaction and cooling, the cleavage reaction residual liquid was weighed, the weight of the reaction residual liquid was 74.27g, the composition was analyzed by gas chromatography, and the composition of each substance in the residual liquid after the cleavage reaction was shown in Table 3.
TABLE 3 Table 3
Figure BDA0003939636190000072
Figure BDA0003939636190000081
The remaining solution after the cleavage reaction of the previous step was transferred to a crystallization reactor, the temperature was set at-15.+ -. 1 ℃ and stirred at 250rpm for 3 hours using a stirring device, and no crystallization occurred.
Example 3
The oligomeric chlorosilane feed composition was the same as in example 1.
77g of the oligomeric chlorosilane raw material liquid is accurately weighed and added into a three-neck round bottom flask to carry out cracking reaction. The cleavage reaction of the oligomeric chlorosilane was carried out in the same manner as in example 1, the cleavage reaction temperature was set to 110℃and the other reaction conditions were the same as in example 1. After the completion of the reaction and cooling, the cleavage reaction residual liquid was weighed, the weight of the cleavage reaction residual liquid was 53.46g, the composition was analyzed by gas chromatography, and the composition of each substance in the cleavage reaction residual liquid was shown in Table 4.
The remaining solution after the cleavage reaction of the previous step was transferred to a crystallization reactor, the temperature was set at-15.+ -. 1 ℃ and stirred at 250rpm for 3 hours using a stirring device, and then transferred to a low temperature filtration device and rapidly filtered with a filter membrane having a pore size of 0.45. Mu.m. Thereby obtaining crystals and a first mother solution. The weight of the crystal is 29.54g, and the main component of the crystal is Si 2 Cl 6 The first mother liquor is mainly the rest Si 2 OCl 6 The composition of each substance in the crystals is shown in Table 4.
TABLE 4 Table 4
Figure BDA0003939636190000082
Example 4
The oligomeric chlorosilane feed composition was the same as in example 1.
77g of the oligomeric chlorosilane raw material liquid is accurately weighed and added into a three-neck round bottom flask to carry out cracking reaction. The process of the cleavage reaction of the oligomeric chlorosilane was the same as in example 1, and the cleavage reaction conditions were the same as in example 1. After the completion of the reaction and cooling, a cleavage reaction residual solution was weighed, the weight of the cleavage reaction residual solution was 61.60g, and the composition was analyzed by gas chromatography, and the composition of each substance in the cleavage reaction residual solution was shown in Table 5.
The remaining solution after the cleavage reaction of the previous step was transferred to a crystallization reactor, the temperature was set at-20.+ -. 1 ℃ and stirred at 250rpm for 3 hours using a stirring device, and then transferred to a low temperature (-20 ℃) filtration device and rapidly filtered with a filter membrane having a pore size of 0.45. Mu.m. Thereby obtaining crystals and a first mother solution. The weight of the crystal is 33.78g, and the main component of the crystal is Si 2 Cl 6 The first mother liquor is mainly the rest Si 2 OCl 6 The composition of each substance in the crystals is shown in Table 5.
TABLE 5
Figure BDA0003939636190000091
Example 5
The raw material liquid is selected to be composed of: contains 69.67% hexachlorodisilane (Si) 2 Cl 6 ) 10.15% hexachlorodisiloxane (Si) 2 OCl 6 ) 14.23% pentachlorodisilane (Si 2 HCl 5 ) 4.72% Tetrachlorosilane (SiCl) 4 ) And 1.23% trichlorosilane (SiHCl) 3 ). The mass percentages are as above.
77g of the oligomeric chlorosilane raw material liquid is accurately weighed and added into a three-neck round bottom flask to carry out cracking reaction. The process of the cleavage reaction of the oligomeric chlorosilane was the same as in example 1, and the cleavage reaction conditions were the same as in example 1. After the completion of the reaction and cooling, a cleavage reaction residual solution was weighed, the weight of the cleavage reaction residual solution was 58.36g, and the composition was analyzed by gas chromatography, and the composition of each substance in the cleavage reaction residual solution was shown in Table 6.
The crystallization process, crystallization conditions and crystallization filtration were the same as in example 1. After the crystals are filtered, the crystals and a first mother solution are obtained. The weight of the crystal is 28.13g, and the main component of the crystal is Si 2 Cl 6 The first mother liquor is mainly the rest Si 2 OCl 6 The composition of each substance in the crystals is shown in Table 6.
TABLE 6
Figure BDA0003939636190000092
Example 6
The raw material liquid is selected to be composed of: contains 83.42% hexachlorodisilane (Si) 2 Cl 6 ) 6.49% hexachlorodisiloxane (Si) 2 OCl 6 ) Pentachlorodisilane (Si) 8.34% 2 HCl 5 ) 1.34% Tetrachlorosilane (SiCl) 4 ) And 0.41% trichlorosilane (SiHCl) 3 ). The mass percentages are as above.
77g of the oligomeric chlorosilane raw material liquid is accurately weighed and added into a three-neck round bottom flask to carry out cracking reaction. The process of the cleavage reaction of the oligomeric chlorosilane was the same as in example 1, and the cleavage reaction conditions were the same as in example 1. After the completion of the reaction and cooling, a cleavage reaction residual solution was weighed, the weight of the cleavage reaction residual solution was 62.78g, and the composition was analyzed by gas chromatography, and the composition of each substance in the cleavage reaction residual solution was shown in Table 7.
The crystallization process, crystallization conditions, crystallization filtration were the same as in example 1. After the crystals are filtered, the crystals and a first mother solution are obtained. The weight of the crystal is 35.75g, and the main component of the crystal is Si 2 Cl 6 The first mother liquor is mainly the rest Si 2 OCl 6 The composition of each substance in the crystals is shown in Table 7.
TABLE 7
Figure BDA0003939636190000101
It should be understood that although the present disclosure has been described in terms of various embodiments, not every embodiment is provided with a separate technical solution, and this description is for clarity only, and those skilled in the art should consider the disclosure as a whole, and the technical solutions in the various embodiments may be combined appropriately to form other embodiments that will be understood by those skilled in the art.
The above list of detailed descriptions is only specific to practical embodiments of the present invention, and they are not intended to limit the scope of the present invention, and all equivalent embodiments or modifications that do not depart from the spirit of the present invention should be included in the scope of the present invention.

Claims (10)

1. A separation method of hexachlorodisilane in polysilicon byproduct oligomeric chlorosilane is characterized in that: the method comprises the following steps:
(1) Cracking reaction is carried out on the byproduct oligomeric chlorosilane of the polysilicon, wherein HCl gas is introduced to react with the byproduct oligomeric chlorosilane of the polysilicon, the reaction temperature is 90-120 ℃, the generated gas is condensed, and the residual liquid of the cracking reaction is collected;
the polysilicon byproduct oligomeric chlorosilane comprises hexachlorodisilane, hexachlorodisiloxane, pentachlorodisilane, tetrachlorosilane and trichlorosilane;
(2) And (3) crystallizing the residual liquid of the cracking reaction at a low temperature, and filtering to separate crystals.
2. The separation method according to claim 1, characterized in that: in step (1), the reaction temperature is 90 to 110℃and preferably 100 ℃.
3. The separation method according to claim 1, characterized in that: in step (1), the reaction time is 15min to 90min, preferably 30min to 60min, and most preferably 30min.
4. The separation method according to claim 1, characterized in that: in the step (1), the introducing speed of the HCl gas is 30mL/min.
5. The separation method according to claim 1, characterized in that: in the step (1), the condensation temperature at the time of condensing and collecting the gas-phase product is-10 ℃.
6. The separation method according to claim 1, characterized in that: in the step (1), N is introduced before the cracking reaction is carried out 2 To replace the air in the container.
7. The separation method according to claim 1, characterized in that: in step (2), the low temperature crystallization temperature is-10 ℃ to 20 ℃, preferably the crystallization temperature is-15 ℃.
8. The separation method according to claim 1, characterized in that: in the step (2), stirring is performed during low-temperature crystallization.
9. The separation method according to claim 1, characterized in that: in the step (2), filtration was performed using a filter membrane having a pore size of 0.45. Mu.m.
10. The separation method according to any one of claims 1 to 9, characterized in that: in the step (2), pentachlorodisilane is not contained in the crystal; preferably, the content of hexachlorodisilane in the crystal is 95.68-97.34% by weight.
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Citations (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61281009A (en) * 1985-06-05 1986-12-11 Koujiyundo Silicon Kk Apparatus for producing polycrystal silicon
JPH09263405A (en) * 1996-01-23 1997-10-07 Tokuyama Corp Production of mixture reduced in hydrogen chloride
JP2007001791A (en) * 2005-06-21 2007-01-11 Mitsubishi Materials Polycrystalline Silicon Corp Method of purifying trichlorosilane
US20100150809A1 (en) * 2008-12-11 2010-06-17 Bill Jr Jon M enhancements for a chlorosilane redistribution reactor
US20110306187A1 (en) * 2008-12-23 2011-12-15 Peter Dold Method and apparatus for silicon refinement
JP2013203649A (en) * 2012-03-29 2013-10-07 Mitsubishi Materials Corp Method of decomposing chlorosilane polymer
CN104909400A (en) * 2014-03-13 2015-09-16 四川瑞能硅材料有限公司 Treatment system and treatment method of chlorosilane slurry raffinate
DE102014007685A1 (en) * 2014-05-21 2015-11-26 Psc Polysilane Chemicals Gmbh Process for the preparation of hexachlorodisilane
CN105271246A (en) * 2015-04-30 2016-01-27 宁夏胜蓝化工环保科技有限公司 Method for preparing chlorinated disilane by utilization of polysilicon byproducts
US20160060126A1 (en) * 2013-04-24 2016-03-03 Evonik Degussa Gmbh Process for the preparation of hexachlorodisilane by cleavage of higher polychlorosilanes such as octachlorotrisilane
CN105531229A (en) * 2013-10-23 2016-04-27 信越化学工业株式会社 Method for manufacturing polycrystalline silicon
CN106698441A (en) * 2015-08-03 2017-05-24 新特能源股份有限公司 Treating method for residual liquid and slag slurry produced in polysilicon production
CN106966397A (en) * 2017-04-06 2017-07-21 洛阳中硅高科技有限公司 The recovery method of disilicone hexachloride
WO2019060475A2 (en) * 2017-09-20 2019-03-28 Momentive Performance Materials Inc. Synthesis of organo chlorosilanes from organosilanes
CN216935386U (en) * 2022-02-23 2022-07-12 乐山协鑫新能源科技有限公司 Chlorosilane tail gas cooling crystallization treatment system
CN217661586U (en) * 2022-05-16 2022-10-28 四川永祥多晶硅有限公司 Polycrystalline silicon high-boiling-point substance separation system

Patent Citations (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61281009A (en) * 1985-06-05 1986-12-11 Koujiyundo Silicon Kk Apparatus for producing polycrystal silicon
JPH09263405A (en) * 1996-01-23 1997-10-07 Tokuyama Corp Production of mixture reduced in hydrogen chloride
JP2007001791A (en) * 2005-06-21 2007-01-11 Mitsubishi Materials Polycrystalline Silicon Corp Method of purifying trichlorosilane
US20100150809A1 (en) * 2008-12-11 2010-06-17 Bill Jr Jon M enhancements for a chlorosilane redistribution reactor
US20110306187A1 (en) * 2008-12-23 2011-12-15 Peter Dold Method and apparatus for silicon refinement
JP2013203649A (en) * 2012-03-29 2013-10-07 Mitsubishi Materials Corp Method of decomposing chlorosilane polymer
US20160060126A1 (en) * 2013-04-24 2016-03-03 Evonik Degussa Gmbh Process for the preparation of hexachlorodisilane by cleavage of higher polychlorosilanes such as octachlorotrisilane
CN105531229A (en) * 2013-10-23 2016-04-27 信越化学工业株式会社 Method for manufacturing polycrystalline silicon
CN104909400A (en) * 2014-03-13 2015-09-16 四川瑞能硅材料有限公司 Treatment system and treatment method of chlorosilane slurry raffinate
DE102014007685A1 (en) * 2014-05-21 2015-11-26 Psc Polysilane Chemicals Gmbh Process for the preparation of hexachlorodisilane
CN105271246A (en) * 2015-04-30 2016-01-27 宁夏胜蓝化工环保科技有限公司 Method for preparing chlorinated disilane by utilization of polysilicon byproducts
CN106698441A (en) * 2015-08-03 2017-05-24 新特能源股份有限公司 Treating method for residual liquid and slag slurry produced in polysilicon production
CN106966397A (en) * 2017-04-06 2017-07-21 洛阳中硅高科技有限公司 The recovery method of disilicone hexachloride
WO2019060475A2 (en) * 2017-09-20 2019-03-28 Momentive Performance Materials Inc. Synthesis of organo chlorosilanes from organosilanes
CN216935386U (en) * 2022-02-23 2022-07-12 乐山协鑫新能源科技有限公司 Chlorosilane tail gas cooling crystallization treatment system
CN217661586U (en) * 2022-05-16 2022-10-28 四川永祥多晶硅有限公司 Polycrystalline silicon high-boiling-point substance separation system

Non-Patent Citations (4)

* Cited by examiner, † Cited by third party
Title
HERRMANN, A ET AL: "Cleavage of the silicon-silicon and silicon-chlorine bond of tBu3Si-SiCl3", 《CHEMISTRYSELECT》, vol. 1, no. 7, 25 May 2016 (2016-05-25), pages 1484 - 1489 *
ZHANG, N ET AL: "Theoretical study on the reaction mechanism of Si2Cl6 and HCl catalyzed by amine catalysts", 《NEW JOURNAL OF CHEMISTRY》, vol. 46, no. 37, 1 September 2022 (2022-09-01), pages 17977 - 17984 *
苗军舰;陈少纯;丘克强;: "西门子法生产多晶硅的热力学", 《无机化学学报》, no. 05, 10 May 2007 (2007-05-10), pages 795 - 801 *
黄国强;杨劲;孙帅帅;: "氯硅烷残液中六氯二硅烷回收工艺的模拟与优化", 《化工进展》, no. 09, 5 September 2013 (2013-09-05), pages 2258 - 2262 *

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