A hydrogenation reaction residue recovery and treatment system and method

Abstract

The present invention discloses a hydrogenation reaction residue recovery and treatment system and method, belonging to the technical field of waste liquid recovery and treatment. The system includes: an evaporation kettle, an aluminum removal reactor, a first distillation column, a titanium removal reactor, a second distillation column, a high-boiling substance catalytic cracking reactor, a third distillation column, a condenser, a chlorosilane storage tank, a slurry tank, a screw conveyor and a hydrolysis tank. The present invention fills the blank of the recovery and treatment of chlorosilane residues, and realizes the stable operation of silane production by the disproportionation method through the recovery and treatment process of chlorosilane residues, ensuring the product quality. The recovery and treatment of chlorosilane residues in the present invention is of great significance for energy conservation, consumption reduction and emission reduction in silane production.

Description

Technical Field

[0001] The present invention belongs to the technical field of waste liquid recovery and treatment, and more specifically relates to a system and method for recovering and treating the residual liquid of a hydrogenation reaction. Background Art

[0002] The application of electronic-grade silane gas covers fields such as integrated circuits, photovoltaic cells, flat panel displays, etc., and continuously extends to emerging markets such as granular silicon and silicon-carbon anode materials. Its production process has been continuously iteratively optimized, and the production capacity and purity have been continuously improved. However, improper treatment of unreacted fine silicon powder and by-product high-boiling substances in the disproportionation production system is likely to cause blockage in subsequent processes, and even lead to shutdown, seriously affecting the stable operation of production. Therefore, the treatment requirements for the residual liquid of chlorosilane during the cold hydrogenation process are particularly important.

[0003] Traditional treatment methods for chlorosilane residual liquid mainly include hydrolysis method, drying method, and filtration method. The hydrolysis method is to discharge the chlorosilane residual liquid into an alkaline hydrolysis tank to directly carry out a hydrolysis reaction, and the reaction produces hydrogen, silicate, and silicon dioxide. However, the reaction between chlorosilane and the alkaline solution is violent, prone to boiling over, difficult to control, and causes waste of chlorosilane. The drying method is to pass the chlorosilane residual liquid through a drying device to recover trichlorosilane and silicon tetrachloride, and the remaining residue is sent to the three wastes station for treatment. The filtration method is to pass the chlorosilane residual liquid through a filtration device to filter out solid impurities such as silicon powder, metal chlorides, and catalysts, and the filtrate is further recycled. After treatment of the chlorosilane residue by the drying method and the filtration method, the chlorosilane cannot be completely removed. These substances are highly toxic and dangerous, and are extremely prone to reaction when contacting with water or air, generating flammable, explosive, and toxic gases, and are also prone to causing environmental pollution. Silicon powder and high-boiling substances (such as FeCl3, AlCl3, TiCl4, HCDS, Polymer, etc.) are extremely prone to fire and explosion accidents during the treatment process.

[0004] Currently, the treatment of chlorosilane residual liquid in silane production is prone to serious waste of raw materials, and there are huge potential safety hazards and environmental pollution. There is no efficient comprehensive treatment process technology for chlorosilane residual liquid. Therefore, how to develop a process for efficiently recovering and treating chlorosilane residual liquid and ensuring the safety and environmental protection of subsequent residue treatment is an urgent problem for those skilled in the art. Summary of the Invention

[0005] In view of this, the present invention provides a system and method for recovering and treating the residual liquid of a hydrogenation reaction.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A system for recovering and treating the residual liquid of a hydrogenation reaction includes: an evaporation kettle, an aluminum removal reactor, a first distillation column, a titanium removal reactor, a second distillation column, a high-boiling substance catalytic cracking reactor, a third distillation column, a condenser, a chlorosilane storage tank, a slurry tank, a screw conveyor, and a hydrolysis tank;

[0008] The bottom outlet of the above-mentioned evaporation kettle is connected to the inlet of the aluminum removal reactor, the top outlet of the above-mentioned aluminum removal reactor is connected to the inlet of the first rectification column, the top outlet of the above-mentioned first rectification column is connected to the inlet of the titanium removal reactor, the top outlet of the above-mentioned titanium removal reactor is connected to the inlet of the second rectification column, the top outlet of the above-mentioned second rectification column is connected to the inlet of the high-boiling catalytic cracking reactor, the top outlet of the above-mentioned high-boiling catalytic cracking reactor is connected to the inlet of the third rectification column, and the bottom outlet of the above-mentioned third rectification column is connected to another inlet of the high-boiling catalytic cracking reactor;

[0009] The top outlet of the above-mentioned evaporation kettle, the condenser and the chlorosilane storage tank are connected in sequence, and the top outlet of the above-mentioned third rectification column, the condenser and the chlorosilane storage tank are connected in sequence;

[0010] The bottom outlet of the above-mentioned aluminum removal reactor, the screw conveyor and the hydrolysis tank are connected in sequence, the bottom outlet of the above-mentioned titanium removal reactor is connected to the slurry tank, and the bottom outlet of the above-mentioned high-boiling catalytic cracking reactor is connected to the slurry tank;

[0011] The above-mentioned connection methods are all connected through pipelines.

[0012] Furthermore, the bottom outlet of the above-mentioned first rectification column is connected to another inlet of the aluminum removal reactor, and the bottom outlet of the above-mentioned second rectification column is connected to another inlet of the titanium removal reactor.

[0013] Furthermore, temperature controllers are provided at the top outlets of the above-mentioned first rectification column, the above-mentioned second rectification column and the above-mentioned third rectification column.

[0014] Furthermore, the above-mentioned evaporation kettle is heated by a steam jacket, a spiral stirring paddle is provided inside the evaporation kettle, the blades of the spiral stirring paddle extend to the outlet of the evaporation kettle to realize forward and reverse rotation, and the evaporation kettle is provided with a weighing module.

[0015] Beneficial effects of adopting the above further technical solutions: The steam jacket heating design is adopted to realize the heating of chlorosilane in the kettle. The evaporation kettle is provided with a weighing module. After the chlorosilane residual liquid is discharged, the content of chlorosilane in the kettle is determined according to the weight change, and the recovery rate is calculated.

[0016] The present invention also provides a method for recycling and treating the residual liquid of the hydrogenation reaction by using the above system, including the following steps:

[0017] (1) Feed the chlorosilane residual liquid into the evaporation kettle, control the temperature of the evaporation kettle at 60 - 120 °C, and trichlorosilane and silicon tetrachloride in the chlorosilane residual liquid are evaporated in gaseous form, and after being condensed and liquefied by the condenser, they enter the chlorosilane storage tank;

[0018] (2) The remaining silicon powder, metal chloride and high-boiling substances in the evaporation kettle are discharged into the aluminum removal reactor;

[0019] (3) Add a complexing agent to the aluminum removal reactor, and under stirring, fully carry out the complexing reaction of aluminum trichloride, controlling the temperature of the complexing reaction to be 45 - 180 °C;

[0020] (4) After the complexing reaction, control the temperatures of the aluminum removal reactor and the first distillation column to be 110 - 200 °C, and hexachloroethylsilane, titanium tetrachloride, and polysilicon atoms near the boiling point enter the first distillation column;

[0021] (5) The complexing products, silicon powder, silicon dioxide, and high-boiling metal chlorides in the chlorosilane residue enter the screw conveyor in a solid state from the bottom of the aluminum removal reactor under stirring, and are transported to the hydrolysis tank for hydrolysis treatment;

[0022] (6) The light components of the first distillation column enter the titanium removal reactor. Add an extractant to the titanium removal reactor, and under stirring, fully carry out the complexing reaction of titanium tetrachloride, controlling the temperature of the complexing reaction to be 45 - 80 °C;

[0023] (7) After the complexing reaction, control the temperatures of the titanium removal reactor and the second distillation column to be 90 - 160 °C, and hexachloroethylsilane and polysilicon atoms near the boiling point enter the second distillation column;

[0024] (8) The complexing products in the chlorosilane residue enter the slurry tank from the bottom of the titanium removal reactor under stirring;

[0025] (9) The light components of the second distillation column enter the high-boiling catalytic cracking reactor. There is a catalyst in the high-boiling catalytic cracking reactor. After the light components of the second distillation column, that is, the residue after removing heavy metal impurities, enter the high-boiling catalytic cracking reactor, introduce cracking gas hydrogen chloride, and control the temperature of the high-boiling catalytic cracking reactor to be 60 - 130 °C;

[0026] (10) Control the temperature of the third distillation column to be 50 - 90 °C. The heavy components are refluxed into the high-boiling catalytic cracking reactor to continue to participate in the cracking reaction, and the light component monosilane product enters the chlorosilane storage tank after being condensed and liquefied by the condenser;

[0027] (11) The catalyst and the unreacted high-boiling substances enter the slurry tank from the bottom of the high-boiling catalytic cracking reactor under stirring.

[0028] Furthermore, in step (3), the above complexing agent is one or more of amino carboxylic acid, sodium salt of amino carboxylic acid, organic phosphoric acid, sodium salt of organic phosphoric acid, hydroxycarboxylate, polyacrylic acid, or hexenyl bis stearamide (EBS).

[0029] Furthermore, the above-mentioned amino carboxylic acid is one or more of EDTA, DTPA, GLDA or NTA; the above-mentioned organic phosphoric acid is one or more of EDTMP, DETPMP, ATMP, HEDP or PBTCA; the above-mentioned hydroxycarboxylate is one or more of citric acid, tartaric acid, oxalic acid, malonic acid, sulfosalicylic acid, acetylacetone, heptanoate, sodium gluconate, sodium alginate (SA) or sodium gluconate; the above-mentioned polyacrylic acid is a maleic acid-acrylic acid copolymer.

[0030] Furthermore, in step (5), the above-mentioned high-boiling metal chloride is one or more of cuprous chloride, copper chloride, ferric chloride, lead chloride or magnesium chloride.

[0031] Furthermore, in step (6), the above-mentioned extractant is one or more of 3-methyltetrahydrofuran, polyethylene glycol or 1,4-dioxane.

[0032] Furthermore, in step (9), the above-mentioned catalyst is one or more of macroporous weakly basic anion exchange resin PA100, Amberlyst A21 produced by Rohm and Haas or N,N-dimethylaniline.

[0033] Furthermore, in steps (4) and (7), the above-mentioned polysilicon atoms near the boiling point are one or more of octamethyltrisiloxane, hexachlorodisiloxane or diethyldichlorosilane.

[0034] Furthermore, in step (6), the above-mentioned stirring speed is 10-60 rpm; in step (8), the above-mentioned stirring speed is 20-80 rpm; in step (11), the above-mentioned stirring speed is 20-100 rpm.

[0035] The working mechanism of the method for recycling and treating the residual liquid of the hydrogenation reaction of the present invention:

[0036] 1. Recovery of chlorosilane: It is required to strictly control the temperature parameters during the recovery process to avoid reintroducing metal chlorides, especially aluminum trichloride, into the circulation system, causing pipeline blockage.

[0037] 2. Complexation of aluminum trichloride: After the preliminary recovery of the chlorosilane residual liquid, the content of hexachloroethylsilane in the high-boiling components is as high as more than 50%, which has a high added value. The boiling point of aluminum trichloride under normal pressure is 178°C, which is close to that of hexachloroethylsilane and is easy to sublimate, condensing on the pipe wall and causing blockage. In order to better separate hexachloroethylsilane, it is necessary to first separate aluminum trichloride. A complexing agent is added to the de-aluminum reactor to react with aluminum trichloride to produce a high-boiling solid product.

[0038] 3. Separation of titanium tetrachloride: Since the boiling points of hexachloroethylsilane (boiling point 145°C) and titanium tetrachloride (boiling point 135°C) in the chlorosilane residual liquid are close, the treatment of titanium tetrachloride is a key factor in the purification of hexachloroethylsilane.

[0039] 4. Catalytic cracking of high-boiling substances such as hexachloroethylsilane: Since there are many high-boiling disilanes and polysilanes in the chlorosilane residue liquid, high-value monosilane products can be obtained through the catalytic cracking of high-boiling substances.

[0040] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention fills the gap in the recovery and treatment of chlorosilane residue liquid. Through the recovery and treatment process of chlorosilane residue liquid, the stable operation of silane production by disproportionation method is realized, and the product quality is guaranteed.

[0041] 1. The present invention directly recovers available trichlorosilane and silicon tetrachloride raw materials to the greatest extent. On the basis of evaporation recovery, subsequent processes such as removal of aluminum trichloride, titanium tetrachloride, and catalytic cracking of high-boiling substances further evaporate and recover, with a recovery rate of over 99%. Trichlorosilane and silicon tetrachloride in the chlorosilane residue liquid are recovered and recycled through an evaporation kettle. It improves the utilization rate of raw materials, reduces potential safety hazards in the subsequent residue treatment process, and is environmentally friendly.

[0042] 2. The present invention effectively removes aluminum trichloride in the production system, avoiding blockage of system equipment and pipelines.

[0043] 3. The content of hexachloroethylsilane in the chlorosilane residue liquid of the present invention is high and has great recovery value; titanium tetrachloride and other heavy metal impurities are effectively removed in advance, avoiding poisoning of the catalyst for subsequent catalytic cracking of high-boiling substances.

[0044] 4. The present invention effectively recovers high-boiling substances and catalytically cracks them into monosilane products. The cracking rate of high-boiling substances is 99.9%. Hexachloroethylsilane is converted into trichlorosilane and silicon tetrachloride, which are then purified and recovered, reducing production costs, having little environmental pollution, high recovery rate of chlorosilane residue liquid, and maximizing economic benefits.

[0045] The recovery and treatment of chlorosilane residue liquid of the present invention are of great significance for energy conservation, consumption reduction, and emission reduction in silane production. Description of the Drawings

[0046] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on the provided drawings.

[0047] Figure 1 The drawing is a schematic structural diagram of the recovery and treatment system for the hydrogenation reaction residue liquid of the present invention;

[0048] In the figure: 1 - evaporation kettle, 2 - aluminum removal reactor, 3 - first distillation column, 4 - titanium removal reactor, 5 - second distillation column, 6 - high-boiling substance catalytic cracking reactor, 7 - third distillation column, 8 - condenser, 9 - chlorosilane storage tank, 10 - slurry tank, 11 - screw conveyor, 12 - hydrolysis tank, 13 - temperature controller. Detailed implementation manners

[0049] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0050] As Figure 1 shown, the hydrogenation reaction residue recovery and treatment system includes: evaporation kettle 1, aluminum removal reactor 2, first distillation column 3, titanium removal reactor 4, second distillation column 5, high-boiling substance catalytic cracking reactor 6, third distillation column 7, condenser 8, chlorosilane storage tank 9, slurry tank 10, screw conveyor 11 and hydrolysis tank 12;

[0051] The bottom outlet of the evaporation kettle 1 is communicated with the inlet of the aluminum removal reactor 2, the top outlet of the aluminum removal reactor 2 is communicated with the inlet of the first distillation column 3, the top outlet of the first distillation column 3 is communicated with the inlet of the titanium removal reactor 4, the top outlet of the titanium removal reactor 4 is communicated with the inlet of the second distillation column 5, the top outlet of the second distillation column 5 is communicated with the inlet of the high-boiling substance catalytic cracking reactor 6, the top outlet of the high-boiling substance catalytic cracking reactor 6 is communicated with the inlet of the third distillation column 7, and the bottom outlet of the third distillation column 7 is communicated with another inlet of the high-boiling substance catalytic cracking reactor 6;

[0052] The top outlet of the evaporation kettle 1, the condenser 8 and the chlorosilane storage tank 9 are communicated in sequence, and the top outlet of the third distillation column 7, the condenser 8 and the chlorosilane storage tank 9 are communicated in sequence;

[0053] The bottom outlet of the aluminum removal reactor 2, the screw conveyor 11 and the hydrolysis tank 12 are communicated in sequence, the bottom outlet of the titanium removal reactor 4 is communicated with the slurry tank 10, and the bottom outlet of the high-boiling substance catalytic cracking reactor 6 is communicated with the slurry tank 10;

[0054] The communication modes are all through pipelines.

[0055] In one embodiment, the bottom outlet of the first distillation column 3 is communicated with another inlet of the aluminum removal reactor 2, and the bottom outlet of the second distillation column 5 is communicated with another inlet of the titanium removal reactor 4.

[0056] In one embodiment, temperature controllers 13 are provided at the top outlets of the first distillation column 3, the second distillation column 5 and the third distillation column 7.

[0057] In one embodiment, the evaporation kettle 1 is heated by a steam jacket. A spiral stirring paddle is provided inside the evaporation kettle 1. The blades of the spiral stirring paddle extend to the outlet of the evaporation kettle 1 and can rotate forward and backward. The evaporation kettle 1 is provided with a weighing module.

[0058] Example 1

[0059] A method for recycling and treating the residue of the hydrogenation reaction includes the following steps:

[0060] (1) Feed the chlorosilane residue into the evaporation kettle 1, control the temperature of the evaporation kettle 1 at 75 °C and the pressure at 175 Kpa (absolute pressure). Trichlorosilane and silicon tetrachloride in the chlorosilane residue are vaporized in gaseous form, and after being condensed and liquefied by the condenser 8, they enter the chlorosilane storage tank 9;

[0061] (2) The remaining silicon powder, metal chlorides and high-boiling substances in the evaporation kettle 1 are discharged into the de-aluminum reactor 2;

[0062] (3) Add a complexing agent to the de-aluminum reactor 2, and under stirring, make aluminum trichloride undergo a full complexation reaction, control the complexation reaction temperature at 116 °C; the complexing agent is hexenyl bis(hardamide) (EBS);

[0063] (4) After the complexation reaction, control the temperatures of the de-aluminum reactor and the first distillation column 3 at 175 °C. Hexachloroethylsilane, titanium tetrachloride and polysilicon atoms near the boiling point enter the first distillation column 3; the polysilicon atoms near the boiling point are octamethyltrisiloxane, hexachlorodisiloxane and diethyldichlorosilane;

[0064] (5) The complexation products, silicon powder, silicon dioxide and high-boiling metal chlorides in the chlorosilane residue enter the screw conveyor 11 from the bottom of the de-aluminum reactor 2 in solid form under stirring, and are transported to the hydrolysis tank 12 for hydrolysis treatment; the high-boiling metal chlorides are cuprous chloride, copper chloride, ferric chloride and magnesium chloride;

[0065] (6) The light components in the first distillation column 3 enter the de-titanium reactor 4. Add an extractant to the de-titanium reactor 4, and under stirring, make titanium tetrachloride undergo a full complexation reaction, control the complexation reaction temperature at 65 °C; the extractant is 3-methyltetrahydrofuran; the stirring speed is 45 rpm;

[0066] (7) After the complexation reaction, control the temperatures of the de-titanium reactor and the second distillation column 5 at 145 °C. Hexachloroethylsilane and polysilicon atoms near the boiling point enter the second distillation column 5; the polysilicon atoms near the boiling point are octamethyltrisiloxane, hexachlorodisiloxane and diethyldichlorosilane;

[0067] (8) The complexation products in the chlorosilane residue enter the slurry tank 10 from the bottom of the de-titanium reactor 4 under stirring; the stirring speed is 60 rpm;

[0068] (9) The light components of the second rectification column 5 enter the high-boiling catalytic cracking reactor 6. There is a catalyst in the high-boiling catalytic cracking reactor 6. After the light components of the second rectification column 5, that is, the residual liquid removing heavy metal impurities, enter the high-boiling catalytic cracking reactor 6, cracking gas hydrogen chloride is introduced, and the temperature of the high-boiling catalytic cracking reactor 6 is controlled at 60 °C; the catalyst is macroporous weakly basic anion exchange resin PA100;

[0069] (10) Control the temperature of the third rectification column 7 at 75 °C and the pressure at 175 Kpa (absolute pressure). The heavy components are refluxed into the high-boiling catalytic cracking reactor 6 to continue to participate in the cracking reaction. The light component monosilane product enters the chlorosilane storage tank 9 after being condensed and liquefied by the condenser 8;

[0070] (11) The catalyst and the unreacted high-boiling substances enter the slurry tank 10 from the bottom of the high-boiling catalytic cracking reactor 6 under stirring; the stirring speed is 80 rpm.

[0071] Example 2

[0072] A method for recycling and treating the hydrogenation reaction residual liquid, comprising the following steps:

[0073] (1) Feed the chlorosilane residual liquid into the evaporation kettle 1, control the temperature of the evaporation kettle 1 at 75 °C and the pressure at 175 Kpa (absolute pressure). Trichlorosilane and silicon tetrachloride in the chlorosilane residual liquid are evaporated in gaseous form, and after being condensed and liquefied by the condenser 8, they enter the chlorosilane storage tank 9;

[0074] (2) The remaining silicon powder, metal chlorides and high-boiling substances in the evaporation kettle 1 are discharged into the de-aluminum reactor 2;

[0075] (3) Add a complexing agent to the de-aluminum reactor 2, and under stirring, make aluminum trichloride fully undergo a complexing reaction, and control the complexing reaction temperature at 85 °C; the complexing agent is sodium glycinate;

[0076] (4) After the complexing reaction, control the temperatures of the de-aluminum reactor and the first rectification column 3 at 175 °C. Hexachloroethylsilane, titanium tetrachloride and polysilicon atoms near the boiling point enter the first rectification column 3; the polysilicon atoms near the boiling point are octamethyltrisiloxane, hexachlorodisiloxane and diethyldichlorosilane;

[0077] (5) The complexation products, silicon powder, silicon dioxide and high-boiling metal chlorides in the chlorosilane residual liquid enter the screw conveyor 11 from the bottom of the de-aluminum reactor 2 in solid form under stirring, and are transported to the hydrolysis tank 12 for hydrolysis treatment; the high-boiling metal chlorides are cuprous chloride, copper chloride, ferric chloride and magnesium chloride;

[0078] (6) The light components of rectification column 1 enter the titanium removal reactor 4, an extractant is added to the titanium removal reactor 4, and titanium tetrachloride is fully complexed under stirring. The temperature of the complexation reaction is controlled at 55 °C; the extractant is polyethylene glycol; the stirring speed is 60 rpm;

[0079] (7) After the complexation reaction, the temperatures of the titanium removal reactor and rectification column 2 are controlled at 145 °C, and hexachloroethylsilane and polysilicon atoms near the boiling point enter rectification column 2; the polysilicon atoms near the boiling point are octamethyltrisiloxane, hexachlorodisiloxane, and diethyldichlorosilane;

[0080] (8) The complexation products in the chlorosilane residue enter the slurry tank 10 from the bottom of the titanium removal reactor 4 under stirring; the stirring speed is 60 rpm;

[0081] (9) The light components of rectification column 2 enter the high-boiling catalytic cracking reactor 6. There is a catalyst in the high-boiling catalytic cracking reactor 6. After the light components of rectification column 2, that is, the residue after removing heavy metal impurities, enter the high-boiling catalytic cracking reactor 6, cracking gas hydrogen chloride is introduced, and the temperature of the high-boiling catalytic cracking reactor 6 is controlled at 85 °C; the catalyst is Amberlyst A21 produced by Rohm and Haas;

[0082] (10) The temperature of rectification column 3 is controlled at 75 °C and the pressure is 175 Kpa (absolute pressure). The heavy components are refluxed into the high-boiling catalytic cracking reactor 6 to continue participating in the cracking reaction. The light component monosilane product enters the chlorosilane storage tank 9 after being condensed and liquefied by the condenser 8;

[0083] (11) The catalyst and unreacted high-boiling components enter the slurry tank 10 from the bottom of the high-boiling catalytic cracking reactor 6 under stirring; the stirring speed is 80 rpm.

[0084] Example 3

[0085] A method for recycling and treating the residue of the hydrogenation reaction, comprising the following steps:

[0086] (1) Feed the chlorosilane residue into the evaporation kettle 1, control the temperature of the evaporation kettle 1 at 75 °C and the pressure at 175 Kpa (absolute pressure). Trichlorosilane and silicon tetrachloride in the chlorosilane residue are evaporated in gaseous form, and after being condensed and liquefied by the condenser 8, they enter the chlorosilane storage tank 9;

[0087] (2) The remaining silicon powder, metal chlorides, and high-boiling components in the evaporation kettle 1 are discharged into the aluminum removal reactor 2;

[0088] (3) Add a complexing agent to the aluminum removal reactor 2, and make aluminum trichloride fully complexed under stirring. Control the temperature of the complexation reaction at 95 °C; the complexing agent is sodium malonate;

[0089] (4) After the complexation reaction, control the temperatures of the aluminum removal reactor and the first distillation column 3 at 175 °C, and hexachloroethylsilane, titanium tetrachloride, and polysilicon atoms near the boiling point enter the first distillation column 3; the polysilicon atoms near the boiling point are octamethyltrisiloxane, hexachlorodisiloxane, and diethyldichlorosilane;

[0090] (5) The complexation products, silicon powder, silicon dioxide, and high-boiling metal chlorides in the chlorosilane residue enter the screw conveyor 11 from the bottom of the aluminum removal reactor 2 in solid form under stirring, and are transported to the hydrolysis tank 12 for hydrolysis treatment; the high-boiling metal chlorides are cuprous chloride, copper chloride, ferric chloride, and magnesium chloride;

[0091] (6) The light components of the first distillation column 3 enter the titanium removal reactor 4, an extractant is added to the titanium removal reactor 4, and titanium tetrachloride is fully complexed under stirring. Control the complexation reaction temperature at 60 °C; the extractant is 1,4-dioxane; the stirring speed is 75 rpm;

[0092] (7) After the complexation reaction, control the temperatures of the titanium removal reactor and the second distillation column 5 at 145 °C, and hexachloroethylsilane and polysilicon atoms near the boiling point enter the second distillation column 5; the polysilicon atoms near the boiling point are octamethyltrisiloxane, hexachlorodisiloxane, and diethyldichlorosilane;

[0093] (8) The complexation products in the chlorosilane residue enter the slurry tank 10 from the bottom of the titanium removal reactor 4 under stirring; the stirring speed is 60 rpm;

[0094] (9) The light components of the second distillation column 5 enter the high-boiling catalytic cracking reactor 6. There is a catalyst in the high-boiling catalytic cracking reactor 6. After the light components of the second distillation column 5, that is, the residue after removing heavy metal impurities, enter the high-boiling catalytic cracking reactor 6, cracking gas hydrogen chloride is introduced, and control the temperature of the high-boiling catalytic cracking reactor 6 at 120 °C; the catalyst is N,N-dimethylaniline;

[0095] (10) Control the temperature of the third distillation column 7 at 75 °C and the pressure at 175 Kpa (absolute pressure). The heavy components are refluxed into the high-boiling catalytic cracking reactor 6 to continue participating in the cracking reaction. The light component monosilane product enters the chlorosilane storage tank 9 after being condensed and liquefied by the condenser 8;

[0096] (11) The catalyst and the unreacted high-boiling substances enter the slurry tank 10 from the bottom of the high-boiling catalytic cracking reactor 6 under stirring; the stirring speed is 100 rpm.

[0097] The recovery treatment results of each example are shown in Table 1.

[0098] Table 1

[0099]

[0100] The description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A hydrogenation reaction residue recovery and treatment system, characterized in that, Including: An evaporation kettle, an aluminum removal reactor, a first distillation column, a titanium removal reactor, a second distillation column, a high-boiling-point substance catalytic cracking reactor, a third distillation column, a condenser, a chlorosilane storage tank, a slurry tank, a screw conveyor and a hydrolysis tank; The bottom outlet of the evaporation kettle is communicated with the inlet of the aluminum removal reactor, the top outlet of the aluminum removal reactor is communicated with the inlet of the first distillation column, the top outlet of the first distillation column is communicated with the inlet of the titanium removal reactor, the top outlet of the titanium removal reactor is communicated with the inlet of the second distillation column, the top outlet of the second distillation column is communicated with the inlet of the high-boiling-point substance catalytic cracking reactor, the top outlet of the high-boiling-point substance catalytic cracking reactor is communicated with the inlet of the third distillation column, and the bottom outlet of the third distillation column is communicated with another inlet of the high-boiling-point substance catalytic cracking reactor; The top outlet of the evaporation kettle, the condenser and the chlorosilane storage tank are communicated in sequence, and the top outlet of the third distillation column, the condenser and the chlorosilane storage tank are communicated in sequence; The bottom outlet of the aluminum removal reactor, the screw conveyor and the hydrolysis tank are communicated in sequence, the bottom outlet of the titanium removal reactor is communicated with the slurry tank, and the bottom outlet of the high-boiling-point substance catalytic cracking reactor is communicated with the slurry tank; All the communications are through pipelines.

2. The hydrogenation reaction residue recovery and treatment system according to claim 1, wherein The bottom outlet of the first distillation column is communicated with another inlet of the aluminum removal reactor, and the bottom outlet of the second distillation column is communicated with another inlet of the titanium removal reactor.

3. The hydrogenation reaction residue recovery and treatment system according to claim 1, characterized in that, Temperature controllers are provided at the top outlets of the first distillation column, the second distillation column and the third distillation column.

4. The hydrogenation reaction residue recovery and treatment system according to claim 1, characterized in that, The evaporation kettle is heated by a steam jacket, a screw stirring paddle is arranged inside the evaporation kettle, the paddle of the screw stirring paddle extends to the outlet of the evaporation kettle to realize forward and reverse rotation, and the evaporation kettle is provided with a weighing module.

5. A method for recycling and treating the residual liquid of the hydrogenation reaction by using the system according to any one of claims 1-4, characterized in that, Including the following steps: (1) Feed the chlorosilane residual liquid into the evaporation kettle, control the temperature of the evaporation kettle at 60 - 120 °C, trichlorosilane and silicon tetrachloride in the chlorosilane residual liquid are evaporated in gaseous form, and after being condensed and liquefied by the condenser, they enter the chlorosilane storage tank; (2) The remaining silicon powder, metal chlorides and high-boiling-point substances in the evaporation kettle are discharged into the aluminum removal reactor; (3) Add a complexing agent into the aluminum removal reactor, and under stirring, make aluminum trichloride fully undergo a complexing reaction, and control the temperature of the complexing reaction at 45 - 180 °C; (4) After the complexing reaction, control the temperatures of the aluminum removal reactor and the first distillation column at 110 - 200 °C, and hexachloroethylsilane, titanium tetrachloride and polysilicon atoms near the boiling point enter the first distillation column; (5) The complexing products, silicon powder, silicon dioxide and high-boiling-point metal chlorides in the chlorosilane residual liquid enter the screw conveyor from the bottom of the aluminum removal reactor in solid form under stirring, and are transported to the hydrolysis tank for hydrolysis treatment; (6) The light components in the first distillation column enter the titanium removal reactor, add an extraction agent into the titanium removal reactor, and under stirring, make titanium tetrachloride fully undergo a complexing reaction, and control the temperature of the complexing reaction at 45 - 80 °C; (7) After the complexing reaction, control the temperatures of the titanium removal reactor and the second distillation column at 90 - 160 °C, and hexachloroethylsilane and polysilicon atoms near the boiling point enter the second distillation column; (8) The complexing products in the chlorosilane residual liquid enter the slurry tank from the bottom of the titanium removal reactor under stirring; The light components of the second distillation column enter the high-boiling catalytic cracking reactor. A catalyst is provided in the high-boiling catalytic cracking reactor. After the light components of the second distillation column, i.e., the residual liquid removing heavy metal impurities, enter the high-boiling catalytic cracking reactor, cracking gas hydrogen chloride is introduced, and the temperature of the high-boiling catalytic cracking reactor is controlled at 60 - 130 °C; The temperature of the third distillation column is controlled at 50 - 90 °C. The heavy components reflux and enter the high-boiling catalytic cracking reactor to continue to participate in the cracking reaction. The light component monosilane product enters the chlorosilane storage tank after being condensed and liquefied by a condenser; The catalyst and the unreacted high-boiling substances enter the slurry tank from the bottom of the reaction high-boiling catalytic cracking reactor under stirring.

6. The method for recycling and treating the residual liquid of the hydrogenation reaction according to claim 5, wherein, In step (3), the complexing agent is one or more of amino carboxylic acid, sodium salt of amino carboxylic acid, organic phosphoric acid, sodium salt of organic phosphoric acid, hydroxycarboxylate, polyacrylic acid, or hexenyl bis stearamide.

7. The method for recycling and treating the residual liquid of the hydrogenation reaction according to claim 5, characterized in that, In step (5), the high-boiling metal chloride is one or more of cuprous chloride, copper chloride, ferric chloride, lead chloride, or magnesium chloride.

8. The method for recycling and treating the hydrogenation reaction residue liquid according to claim 5, wherein, In step (6), the extractant is one or more of 3-methyltetrahydrofuran, polyethylene glycol, or 1,4-dioxane.

9. The method for recycling and treating the hydrogenation reaction residual liquid according to claim 5, characterized in that, In step (9), the catalyst is one or more of macroporous weakly basic anion exchange resin PA100, Amberlyst A21 produced by Rohm and Haas, or N,N-dimethylaniline.

10. The method for recycling and treating the residue liquid of the hydrogenation reaction according to claim 5, characterized in that, In steps (4) and (7), the multi-silicon atoms near the boiling point are one or more of octamethyltrisiloxane, hexachlorodisiloxane, or diethyldichlorosilane.

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