Metal complexing adsorption and cracking reaction coupled high-boiling residue treatment method

Abstract

The invention discloses a metal complexing adsorption and cracking reaction coupled high-boiling residue treatment method, and belongs to the technical field of chlorosilane high-boiling residue recovery. Waste silicon powder, a copper-based catalyst and other solid residues are removed from slag slurry generated by a cold hydrogenation device and a reduction device through a slag slurry recovery device, and silicon tetrachloride is recovered; the obtained chlorosilane high-boiling-point substances and the metal complexing adsorbent are sent to a complexing kettle together, gas in the complexing kettle enters the bottom of a separation tower, hexachlorodisilane and other high-boiling-point substances laterally collected from the middle-lower portion of the separation tower are cooled and then sent to a mixer with hydrogen chloride to be mixed, the mixture enters a knapsack reactor to be subjected to a cracking reaction, and the reacted materials return to the middle of the separation tower; reaction products such as trichlorosilane and silicon tetrachloride are obtained from the top of the separation tower, liquid in the bottom of the separation tower returns to the complexing kettle, and complexing adsorption residues are discharged from the bottom of the complexing kettle; according to the process, metal removal and cracking reaction of the high-boiling residues are simultaneously carried out, so that the service cycle of the catalyst, the conversion rate of the high-boiling residues and the single-pass utilization rate of hydrogen chloride are remarkably improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of high-boiling silane recovery, and particularly relates to a method for treating high-boiling substances by coupling metal complex adsorption and cracking reaction. Background Art

[0002] A large amount of silicon tetrachloride (SiCl4) is by-produced during the preparation of polysilicon by the improved Siemens method and the preparation of silane by the disproportionation of silane. Currently, the cold hydrogenation technology is mainly used to convert it into trichlorosilane raw material (SiHCl3) for recycling. The cold hydrogenation technology uses silicon tetrachloride, silicon powder, and hydrogen as raw materials for low-temperature and high-pressure reaction to synthesize trichlorosilane. In addition, high-boiling silanes (such as pentachloroethylsilane, hexachloroethylsilane, etc.) are also by-produced; due to the metal impurities contained in the silicon powder, metal chlorides are also generated. The boiling points of these by-products are relatively high, and together with the unreacted silicon powder and catalyst, they are discharged from the bottom of the quench tower and the rough separation tower to the slurry recovery device as a slurry for recycling.

[0003] High-boiling silanes such as hexachloroethylsilane are raw materials for electronic chemicals that form silicon nitride films and silicon oxide films on solar panels, liquid crystal panels, and integrated circuits, and have high economic benefits; at the same time, high-boiling silanes can react with hydrogen chloride under the action of a catalyst to be converted into low-boiling silane raw materials for recycling. For example, hexachloroethylsilane reacts with hydrogen chloride to form trichlorosilane and silicon tetrachloride. Therefore, it is necessary to recycle the high-boiling silanes in the slurry. Aluminum trichloride is the main metal impurity dissolved in the high-boiling silanes. It starts to sublime from 120°C, which is lower than the boiling points of most high-boiling silanes (the boiling point of hexachloroethylsilane is 145°C), resulting in difficulty in removing it during the recovery of high-boiling silanes and affecting the quality of high-boiling silanes.

[0004] Patent CN221971506U discloses a continuous cracking and rectification system, including a reduction primary tower, a high-boiling separation tower, a high-boiling cracking separation tower, and a high-boiling cracking reactor, which performs continuous cracking and rectification on the high-boiling silanes by-produced by the polysilicon reduction device. However, the system directly uses the high-boiling substances for reaction without removing the metal chlorides in the high-boiling substances, which will cause catalyst poisoning and device blockage, seriously reducing the service life of the catalyst and the continuity of the device.

[0005] Patent CN221071042U discloses a device for treating chlorosilane slurry and high-boiling substances. This device separates liquid chlorosilane mixture and silicon powder through a membrane separation device and an adsorption device, and then recovers chlorosilane in the high-boiling substances through chlorosilane separation, a flash tank, and a high-boiling cracking tower. The process flow of this device is complex. At the same time, the highly viscous copper-based chloride catalyst contained in the chlorosilane slurry can easily cause blockage of the membrane separation device and the adsorption device. Moreover, the chlorosilane high-boiling substances at the bottom of the chlorosilane separation tower directly undergo cracking reaction without considering the removal of metal chloride impurities in the high-boiling substances, which will cause metal poisoning of the catalyst in the high-boiling cracking tower and seriously affect the use of the catalyst.

[0006] Patent CN219429721U discloses a cold hydrogenation slurry evaporation cracking recovery and treatment device. This device conducts secondary recovery of the slurry through processes such as evaporation, filtration, washing, and cracking. The process flow seems complex, but it only conducts simple treatment on the slurry and also does not consider the influence of metal chlorides. Summary of the Invention

[0007]

Technical Problem to be Solved

[0008] Aiming at the deficiencies of the existing technology, the purpose of the present invention is to provide a method for treating high-boiling substances by coupling metal complexation adsorption and cracking reaction, which conducts metal complexation adsorption removal and cracking reaction on chlorosilane high-boiling substances, obtains reaction products such as trichlorosilane and silicon tetrachloride from the top of the separation tower, and discharges complexation adsorption residues from the bottom of the complexation kettle. Compared with the conventional chlorosilane high-boiling substance cracking methods, the present invention aims to realize simultaneous metal complexation adsorption and cracking reaction on high-boiling substances through a set of high-boiling substance treatment system that couples metal complexation adsorption and cracking reaction, with a simple process flow, significantly improving the catalyst service life, high-boiling substance conversion rate, and single-pass utilization rate of hydrogen chloride.

[0009]

Technical Solution

[0010] In order to achieve the above-mentioned invention purpose, the present invention adopts the following technical solutions.

[0011] A method for treating high-boiling substances by coupling metal complexation adsorption and cracking reaction, which utilizes metal complexation adsorption and cracking reaction for the recycling of high-boiling substances, and improves the catalyst service life and high-boiling substance conversion rate.

[0012] Preferably, the method for treating high-boiling substances by coupling metal complexation adsorption and cracking reaction includes the following steps:

[0013] After the slag slurry generated by the cold hydrogeneration device and the reduction device is removed of solid residues such as waste silicon powder and copper-based catalyst and recovered silicon tetrachloride by the slag slurry recovery device, the obtained chlorosilane high-boiling substances and the metal complex adsorbent are sent to the complexing kettle together. The gas in the complexing kettle enters the bottom of the separation tower. The high-boiling substances such as hexachloroethylsilane collected from the middle and lower parts of the separation tower are cooled in the side draw cooler in turn and pressurized by the side draw pump, and then mixed with hydrogen chloride through a mixer and sent to the backpack reactor for cracking reaction. The reacted materials are returned to the middle part of the separation tower. Trichlorosilane, silicon tetrachloride and other reaction products are obtained at the top of the separation tower, the liquid at the bottom of the separation tower is returned to the complexing kettle, and the complexing adsorption residue is discharged from the bottom of the complexing tower.

[0014] A high-boiling substance treatment system coupling metal complex adsorption and cracking reaction provided by the present invention includes a metal complexing agent tank, a complexing kettle, a separation tower, a condenser, a side draw cooler, a side draw pump, a mixer and a backpack reactor; the complexing kettle is used for the complexing of metal chlorides and the heating and gasification of high-boiling substances; the condenser is used for condensing reaction products such as trichlorosilane and silicon tetrachloride collected from the top of the separation tower; the side draw cooler is used for cooling high-boiling substances such as hexachloroethylsilane collected from the side of the separation tower; the mixer is used for mixing high-boiling substances such as hexachloroethylsilane and hydrogen chloride; the backpack reactor is used for the reaction of high-boiling substances such as hexachloroethylsilane and hydrogen chloride;

[0015] The separation tower is divided into upper, middle and lower sections by a return port and a side draw port, and each section is filled with separation elements of high-efficiency structured packing, trays or a combination of structured packing and trays;

[0016] The metal complexing agent discharge pipeline of the metal complexing agent tank is communicated with the complexing agent inlet of the complexing kettle, the gas phase outlet pipeline of the complexing kettle is communicated with the gas phase inlet at the bottom of the separation tower, the liquid phase discharge pipeline at the bottom of the separation tower is communicated with the liquid phase inlet of the complexing kettle, and the outlet at the bottom of the complexing kettle is communicated with the complexing adsorption residue discharge pipeline;

[0017] The material inlet of the condenser is communicated with the top gas phase outlet of the separation tower, and the material outlet of the condenser is respectively communicated with the top reflux port of the separation tower and the discharge pipeline of reaction products such as trichlorosilane and silicon tetrachloride;

[0018] The material inlet of the side draw cooler is communicated with the middle and lower side draw pipeline of the separation tower, the material outlet of the side draw cooler is communicated with the inlet pipeline of the side draw pump, the outlet pipeline of the side draw pump is connected with the liquid phase inlet of the mixer, the feed pipeline of hydrogen chloride is connected with the gas phase inlet of the mixer, the discharge pipeline of the mixer is connected with the inlet of the backpack reactor, and the discharge pipeline of the backpack reactor is connected with the return port in the middle of the separation tower.

[0019] Preferably, the number of theoretical plates of the separation elements in the upper section of the separation tower is 5-20, the number of theoretical plates of the separation elements in the middle section is 5-20, and the number of theoretical plates of the separation elements in the lower section is 5-20.

[0020] Preferably, the metal complex adsorption is a monovalent or divalent metal chloride, including: sodium chloride, potassium chloride, calcium chloride, magnesium chloride, etc.

[0021] Preferably, the backpack reactor is filled with one or a mixture of solid catalysts such as resins, molecular sieves, MOFs, ZIFs, and COFs loaded with amino or alkali metal functional groups; the operating pressure of the backpack reactor is 0.3 - 1.0 MPaG, and the operating temperature is 50 - 80 °C.

[0022] Preferably, the complexation kettle is a jacketed kettle using a high-grade heat source; the condenser is a condenser using circulating water as the condensing medium; the side-draw cooler is a cooler using circulating water as the condensing medium.

[0023] Preferably, the top pressure of the separation tower is 0.02 - 0.2 MPaG, the top temperature is 40 - 80 °C, the top reflux ratio is (1.0 - 10):1; the material temperature controlled by the side-draw cooler is 50 - 80 °C.

[0024] Compared with the prior art, the present invention has the following advantages and technical effects:

[0025] The present invention provides a method for treating high-boiling substances by coupling metal complex adsorption and cracking reaction. By coupling the complex adsorption technology and the high-boiling cracking technology, the simultaneous metal impurity complex adsorption removal and cracking reaction of high-boiling substances are realized in a set of systems. Compared with the previous cracking methods, the process flow is simple, the catalyst service life and the high-boiling conversion rate are significantly improved, and the single-pass utilization rate of hydrogen chloride reaches more than 98%. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The drawings forming a part of this application are used to provide a further understanding of this application. The schematic embodiments and descriptions thereof of this application are used to explain this application and do not constitute an improper limitation to this application. In the drawings:

[0027] Figure 1 It is the equipment structure and flow chart of a high-boiling substance treatment system for coupling metal complex adsorption and cracking reaction of the present invention, wherein: Ⅰ. Metal complexing agent buffer tank, Ⅱ. Complexation kettle, Ⅲ. Separation tower, Ⅳ. Condenser, Ⅴ. Side-draw cooler, Ⅵ. Side-draw pump, Ⅶ. Mixer, Ⅷ. Backpack reactor. DETAILED DESCRIPTION OF THE INVENTION

[0028] The various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation to the present invention, but should be understood as a more detailed description of certain aspects, characteristics, and implementation schemes of the present invention.

[0029] It should be understood that the terms used in the present invention are only for describing particular embodiments and are not intended to limit the present invention. Additionally, for the numerical ranges in the present invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Each intermediate value within any stated value or stated range, as well as each smaller range between any other stated value or intermediate value within the stated range, is also included in the present invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0030] Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Although the present invention only describes preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials related to the documents. In case of conflict with any incorporated document, the content of this specification shall prevail.

[0031] Without departing from the scope or spirit of the present invention, various improvements and changes can be made to the specific embodiments of the present invention specification, which are obvious to those skilled in the art. Other embodiments obtained from the specification of the present invention are obvious to those skilled in the art. The specification and examples of the present invention are merely exemplary.

[0032] Regarding the terms "comprising", "including", "having", "containing", etc. used herein, they are all open-ended terms, meaning including but not limited to.

[0033] The terms "first", "second", "Ⅰ", "Ⅱ", "Ⅲ", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance. Additionally, terms such as "horizontal" and "vertical" do not mean that the components are required to be absolutely horizontal or hanging vertically, but can be slightly inclined. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined. The term "vertical" in the present invention is perpendicular to the ground direction.

[0034] In the description of the present invention, it should also be noted that unless otherwise clearly specified and defined, the terms "arranged", "installed", "connected", "joined" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0035] All raw materials used in the embodiments of the present invention are obtained through commercial purchase.

[0036] The present invention provides a method for treating high-boiling substances by coupling metal complexation adsorption and cracking reaction. The process flow chart is as Figure 1 shown. The continuous treatment device for carrying out metal complexation adsorption and high-boiling cracking reaction includes a metal complexing agent buffer tank I, a complexing kettle II, a separation tower III, a condenser IV, a side-draw cooler V, a side-draw pump VI, a mixer VII, and a backpack reactor VIII;

[0037] The separation elements in the separation tower III are divided into upper, middle, and lower sections by side-draw ports and return ports. Each section is filled with high-efficiency structured packings, trays, or separation elements composed of a combination of structured packings and trays. The number of theoretical plates in the upper section is 5 - 20, the number of theoretical plates in the middle section is 5 - 20, and the number of theoretical plates in the lower section is 5 - 20;

[0038] The complexing agent discharge pipeline of the metal complexing agent buffer tank I is connected to the complexing agent inlet of the complexing kettle II. The gas-phase outlet pipeline of the complexing kettle II is connected to the bottom gas-phase inlet of the separation tower III. The bottom liquid-phase discharge pipeline of the separation tower III is connected to the complexing kettle II. The outlet at the bottom of the complexing kettle II is connected to the complexing adsorption residue discharge pipeline;

[0039] The material inlet of the condenser IV is connected to the top gas-phase outlet of the separation tower III. The material outlet of the condenser IV is respectively connected to the top reflux port of the separation tower III and the discharge pipeline of reaction products such as trichlorosilane and silicon tetrachloride;

[0040] The inlet of the side-draw cooler V is connected to the middle and lower part side-draw pipeline of the separation tower III. The material outlet of the side-draw cooler V is connected to the inlet pipeline of the side-draw pump VI. The outlet pipeline of the side-draw pump VI and the liquid-phase inlet of the mixer VII are connected. The hydrogen chloride feed pipeline and the gas-phase inlet of the mixer VII are connected. The discharge pipeline of the mixer VII is connected to the inlet of the backpack reactor VIII. The discharge pipeline of the backpack reactor VIII is connected to the return port in the middle of the separation tower III.

[0041] In some embodiments of the present invention, the metal complexing agent is a monovalent or divalent metal chloride, including: sodium chloride, potassium chloride, calcium chloride, magnesium chloride, etc.

[0042] In some embodiments of the present invention, the backpack reactor VIII is filled with solid catalysts such as resins, molecular sieves, MOFs, ZIFs, and COFs loaded with amino or alkali metal functional groups and other porous framework materials. The operating pressure of the backpack reactor VIII is 0.3 - 1.0 MPaG, and the operating temperature is 50 - 80 °C.

[0043] In some embodiments of the present invention, the complexing kettle II is a jacketed kettle using 0.3 - 0.8 MPaG saturated steam as the heat source, the condenser IV is a condenser using circulating water as the condensing medium, and the side-drawing cooler V is a cooler using circulating water as the condensing medium.

[0044] In some embodiments of the present invention, the top pressure of the separation tower III is 0.02 - 0.2 MPaG, the top temperature is 40 - 80 °C, and the top reflux ratio is (1.0 - 10):1; the material temperature controlled by the side-drawing cooler V is 50 - 80 °C.

[0045] The technical solution of the present invention will be further described below through embodiments.

[0046] Example 1

[0047] Accounting and explanation are carried out with the treatment amount of chlorosilane high-boiling substances being 150 kg / h.

[0048] According to Figure 1 the process flow of the high-boiling substance treatment method coupling metal complexation adsorption and cracking reaction, the continuous treatment device for metal complexation adsorption and high-boiling cracking reaction includes a metal complexing agent buffer tank I, a complexing kettle II (using 0.5 MPaG saturated steam as the heat source), a separation tower III, a condenser IV (using circulating water as the condensing medium), a side-drawing cooler V (using circulating water as the condensing medium), a side-drawing pump VI, a mixer VII, and a backpack reactor VIII; the top pressure of the separation tower III is 0.03 MPaG, the top temperature is 57.4 °C, and the top reflux ratio is 1.5:1; the material temperature controlled by the side-drawing cooler V is 60 °C;

[0049] The separation elements in the separation tower III are divided into upper, middle, and lower sections by the side-drawing port and the return port, and each section is filled with high-efficiency structured packing; the number of theoretical plates in the upper section is 10, the number of theoretical plates in the middle section is 10, and the number of theoretical plates in the lower section is 10.

[0050] The complexing agent discharge pipeline of the metal complexing agent buffer tank I is connected to the complexing agent inlet of the complexing kettle II, the gas-phase outlet pipeline of the complexing kettle II is connected to the bottom gas-phase inlet of the separation tower III, the bottom liquid-phase discharge pipeline of the separation tower III is connected to the complexing kettle II, and the outlet at the bottom of the complexing kettle II is connected to the complexing adsorption residue discharge pipeline;

[0051] The material inlet of the condenser IV is connected to the top gas-phase outlet of the separation tower III, and the material outlet of the condenser IV is respectively connected to the top reflux port of the separation tower III and the discharge pipeline of reaction products such as trichlorosilane and tetrachlorosilane;

[0052] The inlet of the side-stream cooler V is connected to the middle and lower side-stream pipeline of the separation column III. The material outlet of the side-stream cooler V is connected to the inlet pipeline of the side-stream pump VI. The outlet pipeline of the side-stream pump VI is connected to the liquid-phase inlet of the mixer VII. The hydrogen chloride feed pipeline is connected to the gas-phase inlet of the mixer VII. The outlet pipeline of the mixer VII is connected to the inlet of the backpack reactor VIII. The outlet pipeline of the backpack reactor VIII is connected to the return port in the middle of the separation column III.

[0053] The metal complexing agent is a mixture consisting of 80% sodium chloride, 15% potassium chloride, and 5% calcium chloride.

[0054] The solid catalyst filled in the backpack reactor VIII is a styrene-based macroporous anion exchange resin loaded with amino groups. The operating pressure of the backpack reactor is 0.5 MPaG, and the operating temperature is 60 °C.

[0055] The chlorosilane high-boiling residues at 95 °C are added to the complexing kettle II at a flow rate of 150 kg / h, the metal complexing agent is added to the complexing kettle II at a flow rate of 10 kg / h, the side-stream flow rate of the separation column III is 133 kg / h, and hydrogen chloride is added to the mixer at a flow rate of 11.5 kg / h. According to the above suitable complexing agent, tower structure, catalyst, and optimized operating conditions, a reaction product with a hexachloroethylsilane content of <0.01% and a mass flow rate of 143.5 kg / h is obtained from the top of the tower, and complexing adsorption residues with a hexachloroethylsilane content of <6% and a mass flow rate of 28 kg / h are discharged from the bottom of the complexing kettle. The conversion rate of hexachloroethylsilane > 98.2%, the single-pass utilization rate of hydrogen chloride > 97%, and the material balance is shown in Table 1.

[0056] Table 1 Material balance of Example 1

[0057]

[0058] Example 2

[0059] Accounting and description are carried out based on a processing capacity of 500 kg / h of chlorosilane high-boiling residues.

[0060] According to Figure 1 the process flow, a method for treating high-boiling residues by coupling metal complexing adsorption and cracking reaction is adopted. The continuous treatment device for metal complexing adsorption and high-boiling cracking reaction includes a metal complexing agent buffer tank I, a complexing kettle II (using 0.5 MPaG saturated steam as the heat source), a separation column III, a condenser IV (using circulating water as the condensation medium), a side-stream cooler V (using circulating water as the condensation medium), a side-stream pump VI, a mixer VII, and a backpack reactor VIII; the top pressure of the separation column III is 0.03 MPaG, the top temperature is 56.5 °C, and the top reflux ratio is 2:1; the material temperature controlled by the side-stream cooler V is 60 °C;

[0061] The separating elements in the separation column III are divided into upper, middle, and lower sections by the side draw port and the return port, and each section is filled with high-efficiency structured packing; the number of theoretical plates in the upper section is 13, the number of theoretical plates in the middle section is 18, and the number of theoretical plates in the lower section is 10.

[0062] The complexing agent discharge pipeline at the bottom of the metal complexing agent buffer tank I is connected to the top of the complexing kettle II. The gas phase outlet of the complexing kettle II is connected to the bottom of the separation column III. The liquid phase outlet at the bottom of the separation column III is connected to the complexing kettle II. The outlet at the bottom of the complexing kettle II is connected to the complexing adsorption residue discharge pipeline.

[0063] The gas phase inlet of the condenser IV is connected to the top gas phase outlet of the separation column III. The liquid phase outlet of the condenser IV is respectively connected to the top reflux port of the separation column III and the discharge pipeline of cracking products such as trichlorosilane and silicon tetrachloride.

[0064] The inlet of the side draw cooler V is connected to the middle and lower part side draw pipeline of the separation column III. The outlet pipeline of the side draw cooler V is connected to the inlet pipeline of the side draw pump VI. The outlet of the side draw pump VI is connected to the inlet of the hydrogen chloride feed pipeline and the mixer VII. The outlet pipeline of the mixer VII is connected to the inlet of the backpack reactor VIII. The outlet pipeline of the backpack reactor VIII is connected to the return port in the middle of the separation column III.

[0065] The metal complexing agent is a mixture of 80% sodium chloride, 10% potassium chloride, and 10% calcium chloride.

[0066] The solid catalyst filled in the backpack reactor VIII is a styrene-based macroporous anion exchange resin loaded with amino groups. The operating pressure of the backpack reactor is 0.5 MPaG, and the operating temperature is 60 °C.

[0067] The chlorosilane high-boiling substances at 80 °C are added to the complexing kettle II at a flow rate of 500 kg / h. The metal complexing agent is added to the complexing kettle II at a flow rate of 38 kg / h. The side draw flow rate of the separation column III is 542 kg / h. Hydrogen chloride is added to the mixer at a flow rate of 46.5 kg / h. According to the above suitable complexing agent, tower structure, catalyst, and optimized operating conditions, a reaction product with a hexachloroethylsilane content < 0.01% and a mass flow rate of 477.3 kg / h is obtained from the top of the tower, and a complexing adsorption residue with a hexachloroethylsilane content < 5% and a mass flow rate of 107.2 kg / h is discharged from the bottom of the complexing kettle. The conversion rate of hexachloroethylsilane > 99%, the utilization rate of hydrogen chloride > 98.5%, and the material balance is shown in Table 2.

[0068] Table 2 Material balance of Example 2

[0069]

[0070]

[0071] From the results of Example 1 and Example 2, it can be found that thanks to the process for treating high-boiling chlorosilanes by coupling metal complex adsorption and cracking reaction, the process presented in the present invention can effectively remove metal impurities, improve the conversion rate of high-boiling substances and the single-pass utilization rate of hydrogen chloride, optimize the process flow, and reduce equipment investment compared with the previous cracking technologies.

[0072] The above is only the preferred specific embodiment of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present application should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A method for treating high boiling materials by coupling metal complex adsorption and cracking reaction, which simultaneously performs metal removal and cracking reaction of high boiling materials; characterized in that: The following steps are involved: The slag slurry produced by the cold hydrogenation device and the reduction device is removed from the solid slag such as waste silicon powder and copper-based catalyst and silicon tetrachloride is recovered by the slag slurry recovery device, and the obtained high-boiling chlorosilanes and metal complex adsorbent are sent to the complex kettle together. The gas of the complex kettle enters the bottom of the separation tower, and the high-boiling chlorosilanes sampled from the side of the middle and lower part of the separation tower are successively sent to the side sampling cooler for cooling and the side sampling pump for pressurization, and then mixed with hydrogen chloride through a mixer and sent to the backpack reactor for cracking reaction. The reacted materials are returned to the middle of the separation tower, and reaction products such as trichlorosilane and silicon tetrachloride are obtained at the top of the separation tower. The liquid in the kettle of the separation tower returns to the complex kettle, and the complex adsorption residue is discharged from the bottom of the complex tower.

2. A high boiling point treatment system coupled with metal complex adsorption and cracking reaction, characterized in that: The high-boiling-material treatment system coupled with metal complex adsorption and cracking reaction treats high-boiling-materials by the high-boiling-material treatment method coupled with metal complex adsorption and cracking reaction according to any one of claims 1 to 8, and comprises a metal complexing agent tank (I), a complexing kettle (II), a separation tower (III), a condenser (IV), a side sampling cooler (V), a side sampling pump (VI), a mixer (VII) and a backpack reactor (VIII); the complexing kettle (II) is used for the complexing of metal chlorides and the heating and gasification of high-boiling-materials of chlorosilane; the condenser (IV) is used for condensing reaction products such as trichlorosilane and silicon tetrachloride collected from the top of the separation tower (III); the side sampling cooler (V) is used for cooling high-boiling-materials such as hexachlorodisilane sampled from the side of the separation tower; the mixer (VII) is used for mixing high-boiling-materials such as hexachlorodisilane with hydrogen chloride; and the backpack reactor (VIII) is used for the reaction of high-boiling-materials such as hexachlorodisilane with hydrogen chloride.

3. The high boiling point treatment and recovery system coupled with metal complex adsorption and cracking reaction according to claim 2 is characterized in that: The separation tower (III) is divided into three sections, namely, upper, middle and lower sections, by a return port and a side sampling port. Each section is filled with high-efficiency structured packing, tower trays or structured packing-tower tray composite separation elements. The number of theoretical plates in the upper section is 5 to 20, the number of theoretical plates in the middle section is 5 to 20, and the number of theoretical plates in the lower section is 5 to 20.

4. The high boiling point treatment system of metal complex adsorption and cracking reaction coupling according to claim 2 is characterized in that: The metal complexing agent discharge pipeline of the metal complexing agent tank (I) is connected to the complexing agent inlet of the complexing kettle (II), the gas phase outlet pipeline of the complexing kettle (II) is connected to the gas phase inlet at the bottom of the separation tower (III), the liquid phase discharge pipeline at the bottom of the separation tower (III) is connected to the liquid phase inlet of the complexing kettle (II), and the outlet at the bottom of the complexing kettle (II) is connected to the discharge pipeline of the complex adsorption residue; The material inlet of the condenser (IV) is connected to the gas phase outlet at the top of the separation tower (III), and the material outlet of the condenser (IV) is respectively connected to the reflux port at the top of the separation tower (III) and the discharge pipelines of the reaction products such as trichlorosilane and silicon tetrachloride; The material inlet of the side sampling cooler (V) is connected to the side sampling pipeline in the middle and lower part of the separation tower (III), the material outlet of the side sampling cooler (V) is connected to the inlet pipeline of the side sampling pump (VI), the outlet pipeline of the side sampling pump (VI) is connected to the liquid phase inlet of the mixer (VII), the feed pipeline of hydrogen chloride is connected to the gas phase inlet of the mixer (VII), the discharge pipeline of the mixer (VII) is connected to the inlet of the backpack reactor (VIII), and the discharge pipeline of the backpack reactor (VIII) is connected to the return port in the middle of the separation tower (III).

5. The high boiling point treatment system of metal complex adsorption and cracking reaction coupling according to claim 2, characterized in that: The metal complex adsorption is a monovalent or divalent metal chloride, including sodium chloride, potassium chloride, calcium chloride, magnesium chloride and the like.

6. The high boiling point treatment system of metal complex adsorption and cracking reaction coupling according to claim 2, characterized in that: The backpack reactor (VIII) is filled with a solid catalyst, including one or more of resins, molecular sieves, MOFs, ZIFs and COFs loaded with amine or alkali metal functional groups; the operating pressure of the backpack reactor (VIII) is 0.3-1.0 MPaG, and the operating temperature is 50-80°C.

7. The high boiling point treatment system of metal complex adsorption and cracking reaction coupling according to claim 2, characterized in that: The complexing kettle (II) is a jacketed kettle using a high-grade heat source; the condenser (IV) is a condenser using circulating water as a condensing medium; and the side-collecting cooler (V) is a cooler using circulating water as a condensing medium.

8. The high boiling point treatment system of metal complex adsorption and cracking reaction coupling according to claim 2, characterized in that: The top pressure of the separation tower (III) is 0.02-0.2 MPaG, the top temperature is 40-80°C, and the top reflux ratio is (1-10):1; the material temperature controlled by the side-collecting cooler (V) is 50-80°C.

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