Equipment and method for removing boron and phosphorus impurities from trichlorosilane

Abstract

The invention relates to the technical field of trichlorosilane processing, in particular to equipment and method for removing boron and phosphorus impurities from trichlorosilane, the equipment comprises an adsorption column used for adsorbing trichlorosilane, the adsorption column is filled with an adsorbent, and the adsorbent is specially used for removing the boron and phosphorus impurities in trichlorosilane; the jacket is arranged on the outer wall of the adsorption column and is used for regulating and controlling the temperature in the adsorption column, a pipeline connected with the jacket is divided into an inlet part and an outlet part, and the inlet part and the outlet part are respectively provided with a regulating valve and a stop valve and are used for controlling a medium and flow which are introduced into the jacket. A multi-section adsorbent and a jacket temperature control system are adopted, so that boron and phosphorus impurities in trichlorosilane are efficiently removed. The design of the multi-section adsorbent allows different types of adsorbents to selectively adsorb specific impurities, so that the removal efficiency is improved. And each adsorbent can exert the optimal performance under different temperature and pressure conditions.

Description

Technical Field

[0001] The invention relates to the technical field of trichlorosilane processing, and in particular to a device and a method for removing boron and phosphorus impurities from trichlorosilane. Background Art

[0002] Electronic-grade chlorosilane has a very wide range of uses, mainly in the electronics and photovoltaic industries, and has a very good market prospect. However, the purity requirements of electronic-grade chlorosilane are very high, and there are strict requirements on the impurity content. At present, electronic-grade products are basically obtained by removing impurities from chlorosilane using multi-stage distillation technology. Some impurities, such as compounds of iron, copper, and manganese, are easier to remove through distillation, but boron and phosphorus impurities basically exist in the form of chlorides (referred to as phosphorus-boron impurities). The properties of these chlorides are similar to those of chlorosilane, and their boiling points are very close to those of chlorosilane. It is very difficult to remove them. Therefore, it is necessary to increase the reflux ratio and reduce the extraction volume during multi-stage distillation to ensure the quality indicators. The energy consumption is very high, the yield is also low, and the product quality is unstable. In recent years, researchers have explored a variety of methods to improve the purity of trichlorosilane, including distillation, reaction, adsorption, and the coupling of these methods. The distillation method is limited by its high energy consumption and high equipment cost, while the adsorption method has attracted attention due to its simple operation, low energy consumption, and strong boron and phosphorus removal capabilities. The adsorption method uses solid adsorbents to adsorb and separate impurities in trichlorosilane, and achieves adsorption separation based on the differences in molecular size and polarity of the compounds.

[0003] Although the adsorption method shows potential in removing boron and phosphorus impurities, the existing technology still has some shortcomings. For example, the regeneration of the adsorbent is difficult to achieve, which limits its efficiency and economy in industrial applications. In addition, although the partial hydrolysis method can remove boron and phosphorus impurities, since water molecules need to overcome the obstruction of a large amount of trichlorosilane before they can contact boron and phosphorus compounds, the gel-like trichlorosilane hydrolyzate has an advantage in the adsorption of boron and phosphorus, thereby affecting the removal efficiency. Although the complexation method has a strong ability to remove boron and phosphorus, in the specific process implementation process, it is necessary to consider specific issues such as the selection and purification of the complexing agent, the complexing conditions and the separation method, among which the selection of the complexing agent is the most critical. In addition, the traditional distillation method consumes a high amount of energy in removing boron and phosphorus, and the equipment cost investment is large. Therefore, the development of a new device and method that can improve the purity of trichlorosilane while reducing energy consumption and equipment investment is of great significance to enhancing the international competitiveness in the field of electronic-grade polysilicon. The present invention is aimed at this technical problem and proposes a new device and method for removing boron and phosphorus impurities from trichlorosilane, aiming to achieve more efficient and low-cost purification of trichlorosilane through innovative adsorption technology. Summary of the invention

[0004] In view of the problems existing in the existing equipment and method for removing boron and phosphorus impurities from trichlorosilane, the present invention is proposed.

[0005] Therefore, the purpose of the present invention is to provide a device and method for removing boron and phosphorus impurities from trichlorosilane. The purpose is that the quality of trichlorosilane directly affects the quality of silane products, and boron and phosphorus are two impurities with high content in trichlorosilane and are difficult to separate. The present application solves the problem of reducing the content of boron and phosphorus impurities in chlorosilane materials to purify the quality of trichlorosilane to electronic grade.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions: a device for removing boron and phosphorus impurities from trichlorosilane, comprising an adsorption column for adsorbing trichlorosilane, wherein an adsorbent is installed inside the adsorption column, and the adsorbent is specifically used to remove boron and phosphorus impurities in trichlorosilane; A jacket is arranged on the outer wall of the adsorption column and is used to adjust the temperature inside the adsorption column. The pipeline connected to the jacket is divided into an inlet and an outlet, and both are provided with a regulating valve and a cut-off valve to control the medium and flow rate entering the jacket.

[0007] As a preferred embodiment of the device for removing boron and phosphorus impurities with trichlorosilane described in the present invention, the adsorbent is an ion exchange resin containing amine, or a chelating resin, or an aluminum gel, or an adsorbent loaded with copper salts, or an adsorbent containing halogen elements, or a siloxane.

[0008] As a preferred solution of the equipment for removing boron and phosphorus impurities with trichlorosilane of the present invention, the jacket can use circulating water, steam condensate, seven-degree water, ethylene glycol of different concentrations or temperatures, etc. to heat or cool the material.

[0009] As a preferred solution of the device for removing boron and phosphorus impurities with trichlorosilane of the present invention, the adsorbent in the adsorption column is provided with multiple sections, and each section of the adsorbent is fixed by a supporting structure and a pressing structure.

[0010] As a preferred solution of the equipment for removing boron and phosphorus impurities from trichlorosilane of the present invention, a sewage pipe is arranged at the bottom of the adsorption column, a trichlorosilane feed pipe containing boron and phosphorus impurities is arranged at the lower end of the side, and a safety discharge pipe and a high-purity trichlorosilane product discharge pipe are arranged at the upper end.

[0011] As a preferred embodiment of the equipment for removing boron and phosphorus impurities from trichlorosilane according to the present invention, a feed pipe is arranged at the upper end of the jacket, and a discharge pipe is arranged at the lower end, and two branch pipes, a refrigerant pipe and a heat medium pipe, are separated at the ends of the feed pipe and the discharge pipe, and regulating valves are arranged on the main pipes of the feed pipe and the discharge pipe, and a cut-off valve is arranged on each branch pipe.

[0012] As a preferred solution of the equipment for removing boron and phosphorus impurities with trichlorosilane of the present invention, a plurality of temperature sensors are arranged on the adsorption column, which are arranged in sequence along the vertical direction.

[0013] In order to solve the above technical problems, the present invention provides the following technical solutions: a method for removing boron and phosphorus impurities with trichlorosilane, comprising the above-mentioned equipment for removing boron and phosphorus impurities with trichlorosilane, and comprising the following steps: The trichlorosilane material containing boron and phosphorus is transported to the bottom of the adsorption column; Boron and phosphorus impurities are adsorbed by adsorbents to obtain high-purity trichlorosilane, which is exported from the top of the equipment; The temperature and pressure inside the adsorption column are controlled to maintain optimal adsorption conditions.

[0014] As a preferred embodiment of the method for removing boron and phosphorus impurities with trichlorosilane of the present invention, the temperature control range of the adsorption column is between -30°C and 80°C, the pressure control range is between 0.5 and 1.5 MPaG, and the flow rate through the adsorption column is controlled between 0.2 and 3 m³ / h.

[0015] As a preferred embodiment of the method for removing boron and phosphorus impurities by trichlorosilane of the present invention, it further comprises: after the adsorption of the adsorbent reaches saturation, restoring the adsorption capacity of the adsorbent through a regeneration process, wherein the regeneration process is thermal regeneration or chemical regeneration.

[0016] The beneficial effect of the present invention is that a multi-stage adsorbent and a jacket temperature control system are used, which are highly adaptable to achieve efficient removal of boron and phosphorus impurities in trichlorosilane. The design of the multi-stage adsorbent allows different types of adsorbents to selectively adsorb specific impurities, thereby improving the removal efficiency. For example, amine-type ion exchange resins, chelate resins, aluminum gels, adsorbents loaded with copper salts, adsorbents containing halogen elements, or siloxanes, each of which can perform optimally under different temperature and pressure conditions. The jacket temperature control system ensures accurate control of the internal temperature of the adsorption column, which is crucial to the performance of the adsorbent. Through different media such as circulating water, steam condensate, seven-degree water, ethylene glycol of different concentrations or temperatures, the jacket can achieve accurate control of the internal temperature of the adsorption column, whether it is heating or cooling, it can ensure that the adsorption process is carried out under optimal conditions. This temperature control not only improves the adsorption efficiency, but also helps to protect the adsorbent and extend its service life. In summary, this patent achieves efficient removal of boron and phosphorus impurities in trichlorosilane through the synergistic effect of multi-stage adsorbents and jacket temperature control systems, meeting the high purity requirements of electronic-grade products while reducing operating costs and improving economic benefits and environmental friendliness. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0018] Figure 1 This is a schematic diagram of the overall structure of the equipment for removing boron and phosphorus impurities from trichlorosilane according to the present invention.

[0019] Figure 2 It is a schematic diagram of the internal structure of the adsorption column of the present invention.

[0020] In the figure: 100. Adsorption column; 101. Drain pipe; 102. Trichlorosilane feed pipe; 103. Safety discharge pipe; 104. High-purity trichlorosilane product discharge pipe; 200, jacket; 201, feed pipe; 201a, first pipe; 201b, second pipe; 202, discharge pipe; 202a, third pipe; 202b, fourth pipe; 300, adsorbent; 400. Temperature sensor. DETAILED DESCRIPTION

[0021] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0022] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0023] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0024] Secondly, the present invention is described in detail with reference to the schematic diagram. When describing the embodiments of the present invention in detail, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0025] Reference Figure 1- Figure 2 , which is the first embodiment of the present invention, provides a device for removing boron and phosphorus impurities from trichlorosilane, including an adsorption column 100 for adsorbing trichlorosilane, wherein the adsorption column 100 is filled with an adsorbent 300, and the adsorbent 300 is specifically used to remove boron and phosphorus impurities in trichlorosilane; a jacket 200 is arranged on the outer wall of the adsorption column 100, and is used to adjust the temperature inside the adsorption column 100, and the pipeline connected to the jacket 200 is divided into an inlet and an outlet, and both are provided with a regulating valve and a cut-off valve, which are used to control the medium and flow rate entering the jacket 200.

[0026] It should be explained that the adsorption column 100 is used for adsorption treatment of trichlorosilane. The adsorption column 100 is filled with a specific adsorbent 300, which is specially designed to capture and remove boron and phosphorus impurities in trichlorosilane. The selection and characteristics of the adsorbent 300 are crucial to the effect of the entire impurity removal process.

[0027] Jacket 200: This is a component surrounding the outer wall of the adsorption column 100, and its main function is to regulate and control the temperature inside the adsorption column 100. Temperature has a significant impact on the efficiency of the adsorption process and the performance of the adsorbent 300, so accurate temperature control is necessary. Pipes and valves: The jacket 200 is connected to the external system through two parts of the pipe, the inlet and outlet pipes, which are used to transport the medium required for temperature regulation (such as coolant or heating liquid). Regulating valves and shut-off valves are installed on the pipeline. The regulating valve is used to adjust the flow of the medium to accurately control the temperature inside the jacket 200; the shut-off valve is used to cut off the flow of the medium when necessary to stop temperature regulation.

[0028] The design of this equipment allows operation under different process conditions, optimizing the performance of the adsorbent 300 by adjusting the temperature in the jacket 200, thereby improving the purity of trichlorosilane. The entire system is designed to provide an efficient and controllable adsorption environment to meet the needs of high-purity trichlorosilane in industrial production.

[0029] A sewage pipe 101 is disposed at the bottom of the adsorption column 100, a trichlorosilane feed pipe 102 containing boron and phosphorus impurities is disposed at the lower end of the side, and a safety discharge pipe 103 and a high-purity trichlorosilane product discharge pipe 104 are disposed at the upper end.

[0030] It should be explained that the drain pipe 101 is provided at the bottom of the adsorption column 100, which is a pipe for discharging waste and impurities collected during the adsorption process. During the adsorption process, unwanted substances or impurities will be captured by the adsorbent 300. As time goes by, these adsorbed substances need to be regularly removed to maintain the efficiency of the adsorption column 100 and avoid clogging. The drain pipe 101 is a channel for discharging these wastes.

[0031] Reference Figure 1 , trichlorosilane feed pipe 102 containing boron and phosphorus impurities: A trichlorosilane feed pipe 102 containing boron and phosphorus impurities is arranged at the lower end of the side, which is a pipe for introducing trichlorosilane raw materials containing boron and phosphorus impurities into the adsorption column 100. The trichlorosilane feed pipe 102 is designed to be at a lower position, which helps the raw materials to fully contact with the adsorbent 300 in the adsorption column 100, thereby improving the efficiency of removing impurities.

[0032] Safety relief pipe 103: The upper end is provided with a safety relief pipe 103, which is a safety device used to release pressure when the system pressure is too high to prevent equipment damage or danger. The safety relief pipe 103 can be automatically opened in an emergency to protect the safety of the entire system and operators.

[0033] High-purity trichlorosilane product discharge pipe 104: The high-purity trichlorosilane product discharge pipe 104, also located at the upper end, is a pipe for collecting trichlorosilane products with high purity after adsorption treatment. This pipe guides the pure product out of the adsorption column 100 and sends it to subsequent storage or use links.

[0034] A branch pipeline is provided above the trichlorosilane feed pipe 102 containing boron and phosphorus impurities, which is a replacement pipeline, and is used for replacing materials inside the equipment. When the adsorbent 300 needs to be replaced or the equipment needs to be maintained, the materials inside the equipment must be discharged first to avoid contact between the materials and the new adsorbent 300 or damage to the equipment. By connecting the replacement pipeline, the materials inside the equipment can be guided to a designated container or processing system to ensure complete discharge of the materials. Its function is to safely and effectively discharge the materials inside the equipment during this process.

[0035] Reference Figure 1 A feed pipe 201 is provided at the upper end of the jacket 200, and a discharge pipe 202 is provided at the lower end. Two branch pipes, a refrigerant pipe and a heat medium pipe, are separated at the ends of the feed pipe 201 and the discharge pipe 202. A regulating valve is installed on the main pipe of the feed pipe 201, and a shut-off valve is installed on each branch pipe.

[0036] It should be noted that the feed pipe 201 is set at the top and the discharge pipe 202 is set at the bottom, mainly using gravity to introduce the material into the jacket 200, and it can flow out of the jacket 200 smoothly, realizing the loading and unloading of the material without other power, wherein the material is a specific heat medium or refrigerant.

[0037] Reference Figure 1The main pipes of the feed pipeline 201 and the discharge pipeline 202 are equipped with regulating valves. The main function of the regulating valves is to control the flow rate of the fluid, so as to accurately adjust the temperature inside the jacket 200. The regulating valve can adjust the opening as needed to achieve fine control of the temperature. The refrigerant pipes and heat medium pipes corresponding to the feed pipeline 201 and the discharge pipeline 202 are each equipped with a shut-off valve. The main function of the shut-off valve is to cut off the flow of the fluid when necessary to stop the cooling or heating process. The shut-off valve usually works in two states, fully open or fully closed, to ensure that there is no fluid leakage when closed. The main pipe of the feed pipeline 201 is equipped with a bypass valve, which is used to provide a flexible adjustment means for the process. On the one hand, when the feed flow or pressure needs to be adjusted quickly, part of the fluid can be diverted by opening the bypass valve, thereby effectively reducing the flow or pressure entering the adsorption column 100 to adapt it to different process requirements. On the other hand, in the initial stage of system startup, the bypass valve can gradually increase the feed amount by adjusting the opening, helping the adsorption 100 to smoothly reach a stable working state and avoid equipment shock or unstable adsorption efficiency caused by sudden changes in feed amount.

[0038] The two branch pipes of the refrigerant and the heat medium corresponding to the feed pipe 201 are the first branch pipe 201a and the second branch pipe 201b, respectively, and the two branch pipes of the refrigerant and the heat medium corresponding to the discharge pipe 202 are the third branch pipe 202a and the fourth branch pipe 202b, respectively. The reason why the refrigerant pipe and the heat medium pipe are arranged at the ends of the feed pipe 201 and the discharge pipe 202 is that when it is necessary to reduce the temperature in the jacket 200, the refrigerant enters the jacket 200 through the first branch pipe 201a at the end of the feed pipe 201, and absorbs heat after contacting the inner wall of the jacket 200, thereby reducing the temperature in the jacket 200. Subsequently, the refrigerant with increased temperature is discharged through the third branch pipe 202a at the end of the discharge pipe 202, completing the cooling cycle. On the contrary, when the process requires to increase the temperature in the jacket 200, the heat medium (such as steam or hot water) enters the jacket 200 through the second branch pipe 201b at the end of the feed pipe 201, releases heat to heat the inner wall of the jacket 200, and then increases the temperature in the jacket 200. The heated heat medium is discharged through the fourth branch pipe 202b at the end of the discharge pipe 202, completing the temperature increase cycle. This design meets the situation of flexible temperature adjustment under different process requirements, not only improves the efficiency of temperature control, but also ensures the stability and safety of the process, because it allows continuous and uniform temperature adjustment, reducing the potential impact of temperature fluctuations on product quality and equipment performance.

[0039] The inside of the jacket 200 may be circulating water, steam condensate, seven-degree water or ethylene glycol of different concentrations and temperatures. These media enter and are discharged through the inlet and outlet pipes of the jacket 200, and heat is exchanged with the inner wall of the equipment, thereby adjusting the temperature of the internal material. For example, when the temperature needs to be increased, a hot medium such as steam condensate or ethylene glycol aqueous solution can be circulated through the jacket 200. These hot media release heat in the jacket 200 to increase the temperature of the material in the tank; and when the temperature needs to be reduced, a cold medium such as water is circulated to absorb the heat of the material in the tank to achieve a cooling effect. The design of the jacket 200 makes temperature control more accurate and efficient, which is crucial for keeping chemical reactions or physical processes at a specific temperature, which has a significant impact on improving process efficiency and product quality, wherein the refrigerant and the heat medium are the same medium when used at the same time.

[0040] In industrial applications, the adsorbent 300 often contains a certain amount of moisture after installation, and this moisture needs to be removed to ensure the adsorption effect. Traditional drying methods may be costly, and steam drying using the jacket 200 is an economical and efficient way. Specifically, the jacket 200 can be used as a drying device for the adsorbent 300, and the temperature is increased by passing steam into the jacket 200, thereby achieving the drying of the adsorbent 300. This method can not only quickly remove the moisture in the adsorbent 300, but also because the heat of the steam can be recycled, the cost of steam drying is lower than other drying technologies and it is more economical. In addition, the application of the jacket 200 drying technology can also improve the drying efficiency, enhance the stability of the material, and has the characteristics of high flexibility, safety and easy maintenance. In this way, we can ensure that the adsorbent 300 reaches the best state before it is put into use, thereby improving the efficiency and effect of the entire adsorption process.

[0041] Reference Figure 1 - Figure 2 , wherein the adsorbent 300 in the adsorption column 100 is provided with multiple sections, and each section of the adsorbent 300 is fixed by a supporting structure and a pressing structure.

[0042] It should be explained that the supporting structure functions similarly to a filter screen, and its function is to separate the adsorbent 300 into sections to prevent uneven distribution of the adsorbent 300 when it moves or settles inside the adsorption column 100. This structure is usually composed of a porous plate or a grid, which can evenly distribute the weight and prevent the adsorbent 300 from shifting or collapsing during operation. In some designs, the supporting structure may include a wire mesh or a porous plate, which allows fluid to pass through while supporting the adsorbent 300.

[0043] The compression structure is used to fix the adsorbent 300 and ensure that it remains tightly packed in the adsorption column 100, thereby maximizing the contact area between the adsorbent 300 and the fluid. This structure may include an annular pressure plate or a similar fixing device, which compresses the adsorbent 300 after it is loaded into the adsorption column 100 to prevent the adsorbent 300 from moving when the fluid flows. The compression structure helps maintain the stability and uniformity of the adsorbent 300 bed, thereby improving the adsorption efficiency.

[0044] The combined use of the support structure and the compression structure can ensure that the adsorbent 300 forms a uniform and stable bed in the adsorption column 100. This design helps to improve the efficiency of the fluid passing through the adsorbent 300, because the fluid can evenly contact the adsorbent 300, thereby improving the adsorption effect. At the same time, this structure can also reduce the wear and breakage of the adsorbent 300 and extend its service life. In actual operation, the design of the support structure and the compression structure needs to take into account the physical properties of the adsorbent 300 and the operating conditions of the adsorption column 100. For example, it is necessary to select a suitable pore size and structural strength to ensure that the adsorbent 300 does not leak into the fluid while being able to withstand pressure and temperature changes during operation.

[0045] In the adsorption column 100, the adsorbent 300 is divided into multiple sections and fixed by a supporting structure and a compression structure. Such a design not only ensures the stability of the adsorbent 300, but also helps to achieve the mixed flow effect of the gas. Specifically, in the traditional single-stage adsorbent 300, the adsorbent 300 is usually filled in the entire adsorption column 100 without being processed in sections. Although this method is simple, it has some obvious shortcomings in actual operation. First, the single-stage adsorbent 300 cannot be evenly distributed, resulting in insufficient contact area between the fluid and the adsorbent 300, thereby reducing the adsorption efficiency. Secondly, the single-stage adsorbent 300 is prone to channeling, that is, the fluid passes quickly along certain paths of the adsorption column 100 without sufficient contact with the adsorbent 300, which further affects the adsorption effect.

[0046] In contrast, in a specific embodiment, the support structure and the clamping structure are filter screens with pore sizes no larger than those of the adsorbent particles, which separate the adsorbent 300 into sections, and a specific installation method is that the support structure is located below each section of the adsorbent, and the support structure located at the bottom is placed on the upper surface of the first annular step provided on the inner wall of the adsorption column; the clamping structure is located above each section of the adsorbent, and the clamping structure located at the top is installed on the lower surface of the second annular step provided inside the adsorption column through a spring; the support structure and the clamping structure located in the middle are placed horizontally in the adsorption column and can be adaptively raised and lowered, wherein the first annular step and the second annular step are both welded to the inner wall of the adsorption column, and the first annular step is provided above the trichlorosilane feed pipe 102, and the second annular step is provided below the safety discharge pipe 103 or the high-purity trichlorosilane product discharge pipe 104.

[0047] The advantages of doing so are: (1) Uniform distribution: After the adsorbent 300 is divided into multiple sections, each section is fixed so that each section can be evenly distributed in the entire adsorption column 100, ensuring that the contact area between the fluid and the adsorbent 300 is maximized when the fluid passes through, thereby improving the adsorption efficiency. (2) Preventing channeling: In the absence of separation, the fluid may pass quickly along certain paths of the adsorption column 100 without fully contacting the adsorbent 300. This phenomenon is called channeling. By dividing the adsorbent 300 into sections, the channeling phenomenon can be reduced, allowing the fluid to pass through the adsorbent 300 bed more evenly. (3) Mixing effect: In the adsorbent 300 bed, the flow of the fluid may be uneven due to the resistance of the adsorbent 300. The design of the support structure and the compression structure helps to break this unevenness, promote the mixing of the fluid in the adsorbent 300 bed, and further improve the adsorption efficiency. (4) Maintaining bed stability: During the adsorption and desorption cycle, the adsorbent 300 may change its volume due to expansion and contraction. The compression structure can maintain the compact state of the adsorbent 300 bed, reduce the decrease in compression force caused by the sedimentation of the adsorbent 300, and keep the adsorbent 300 always in a compressed state, thereby improving the adsorption efficiency and stability. In summary, dividing the adsorbent 300 into sections by the support structure and the compression structure not only helps to improve the adsorption efficiency, but also ensures sufficient contact between the fluid and the adsorbent 300 through the mixing effect, which is crucial to improving the effect of the entire adsorption process.

[0048] Reference Figure 2 A plurality of temperature sensors 400 are disposed on the adsorption column 100 , and are arranged in sequence along the vertical direction.

[0049] It should be explained that in the design of the adsorption column 100, in order to achieve precise temperature control, a plurality of temperature sensors 400 are usually arranged on the column, which correspond to each section of the adsorbent 300 and are arranged in sequence along the vertical direction. Such a layout allows real-time monitoring of the temperature of different areas inside the adsorption column 100 to ensure that each segment of the adsorbent 300 works under the optimal temperature conditions. The temperature sensor 400 is responsible for directly measuring the temperature and converting the temperature change into an electrical signal output. The inlet of the refrigerant or heat medium of the jacket 200 is flow-regulated by a regulating valve, so that the flow of the refrigerant or heat medium entering the jacket 200 can be finely controlled, thereby adjusting the temperature inside the adsorption column 100. Through this design, the temperature control of the adsorption column 100 can be fully automated, which is achieved by the central control system combined with the instrument automation of the temperature sensor 400. This means that the temperature control process can be carried out automatically according to the preset program without manual intervention, which improves the convenience and safety of operation, and also ensures the stability and efficiency of the adsorption process.

[0050] Reference Figure 1 - Figure 2 The working process of the adsorption column 100 involves purifying trichlorosilane containing impurities through an adsorption process to remove impurities such as boron and phosphorus. The following is a detailed explanation of the working process of the adsorption column 100:

[0051] Feeding stage: The trichlorosilane raw material containing boron and phosphorus impurities enters the adsorption column 100 through the feeding pipe at the lower end of the side. The selection of this position helps the raw material to fully contact with the adsorbent 300 during the rising process, thereby improving the adsorption efficiency.

[0052] Adsorption process: When the trichlorosilane raw material passes through the adsorption column 100, it contacts the adsorbent 300 filled in the column. The adsorbent 300 selectively adsorbs the boron and phosphorus impurities in the trichlorosilane according to its chemical properties and physical structure.

[0053] The adsorbent 300 generally has a high specific surface area to increase the contact area with impurities in trichlorosilane and improve the adsorption efficiency.

[0054] Impurity Removal: As the trichlorosilane feedstock flows, the boron and phosphorus impurities are captured by the adsorbent 300 and are thus separated from the trichlorosilane.

[0055] Product collection: The high-purity trichlorosilane that has undergone adsorption treatment flows out through the high-purity trichlorosilane product discharge pipe 104 at the upper end and enters the subsequent storage or use link.

[0056] Pressure control and safety release: A safety release pipe 103 is provided at the upper end of the adsorption column 100 to release the pressure when the system pressure is too high, so as to protect the safety of the equipment and operators.

[0057] Drainage and regeneration of adsorbent 300: The drain pipe 101 at the bottom of the adsorption column 100 is used to regularly discharge waste and impurities captured by the adsorbent 300 to maintain the working efficiency of the adsorption column 100. The adsorbent 300 will reach a saturated state after being used for a period of time, and a specific regeneration process (such as thermal regeneration, chemical regeneration, etc.) is required to restore its adsorption capacity.

[0058] Monitoring and control: Thermometers and pressure transmitters are provided at different positions of the adsorption column 100 to monitor the process status inside the adsorption column 100 and ensure that the adsorption process is carried out under optimal conditions.

[0059] The entire adsorption column 100 workflow is a continuous process that requires precise control and regular maintenance to ensure the purity and adsorption efficiency of trichlorosilane. Through this process, impurities such as boron and phosphorus can be effectively removed from trichlorosilane to produce a high-purity product.

[0060] Reference Figure 1 - Figure 2 , which is the second embodiment of the present invention, and this embodiment is different from the first embodiment in that: a method for removing boron and phosphorus impurities from trichlorosilane, including equipment for removing boron and phosphorus impurities from trichlorosilane, and comprising the following steps: The trichlorosilane material containing boron and phosphorus is transported to the bottom of the adsorption column 100; The boron and phosphorus impurities are adsorbed by the adsorbent 300, and high-purity trichlorosilane is obtained and discharged from the top of the equipment; The temperature and pressure inside the adsorption column 100 are controlled to maintain optimal adsorption conditions.

[0061] The adsorbent 300 is an ion exchange resin containing an amine, or a chelate resin, or an aluminum gel, or an adsorbent 300 loaded with copper salts, or an adsorbent 300 containing halogen elements, or a siloxane.

[0062] The selection of amine-containing ion exchange resins, chelate resins, aluminum gels, adsorbents 300 loaded with copper salts, adsorbents 300 containing halogen elements, or siloxanes as the basis for removing boron and phosphorus impurities in trichlorosilane is mainly based on their unique chemical properties and adsorption capacity. The lone pair electrons of nitrogen atoms on amine-type ion exchange resins can form complexes with boron to effectively remove boron impurities. Copper salts are particularly suitable for removing phosphorus impurities due to their strong complexing ability. By loading on a porous carrier with a large specific surface area, such as silicon dioxide, the contact area between chlorosilane and the complexing agent can be increased, thereby improving the efficiency of phosphorus removal. In addition, during the preparation process of the copper salt-loaded adsorbent 300, copper is reduced from +2 valence to 0 valence through steps such as impregnation and heating, thereby enhancing its adsorption performance. Chelating resins and aluminum gels can provide a large number of active sites due to their porous structure and surface activity, thereby enhancing the adsorption capacity of impurities. The adsorbent 300 containing halogen elements can form a strong chemical bond with specific impurities, thereby achieving selective adsorption. Siloxane adsorbents 300, due to their unique surface properties, can form stable complexes with a variety of impurities, which helps to improve adsorption efficiency. The selection of these adsorbents 300 takes into account their chemical activity, physical structure and economic efficiency to ensure an efficient, economical and stable trichlorosilane purification process in industrial applications.

[0063] The temperature control range of the adsorption column 100 is between -30°C and 80°C, the pressure control range is between 0.5 and 1.5 MPaG, and the flow rate flowing through the adsorption column 100 is controlled between 0.2 and 3 m³ / h.

[0064] The temperature, pressure and flow control of the adsorption column 100 are key factors to ensure the efficiency and safety of the adsorption process. The temperature control range is between -30℃ and 80℃, because the performance and adsorption efficiency of the adsorbent 300 often change with temperature. Low temperature can slow down the degradation rate of the adsorbent 300, while suitable high temperature can improve the adsorption efficiency. The pressure control range is between 0.5 and 1.5MPaG, which is to maintain the appropriate fluidity of the fluid in the adsorption column 100 and the stability of the adsorbent 300 bed. Too low pressure may cause poor fluid flow, while too high pressure may damage the adsorbent 300 bed or equipment. The flow rate through the adsorption column 100 is controlled between 0.2 and 3m³ / h to ensure that the fluid has sufficient contact time with the adsorbent 300 to achieve the best adsorption effect. Too low flow rate may lead to a decrease in adsorption efficiency, while too high flow rate may cause the adsorbent 300 to be saturated too quickly, affecting the adsorption effect. By accurately controlling these parameters, the adsorption process can be optimized, the product purity and yield can be improved, and the safety of the operation can be ensured.

[0065] The method further includes restoring the adsorption capacity of the adsorbent 300 through a regeneration process after the adsorption of the adsorbent 300 reaches saturation, and the regeneration process is thermal regeneration or chemical regeneration.

[0066] After being used for a period of time, the adsorbent 300 will gradually become saturated due to the adsorption of a large amount of impurities. At this time, regeneration treatment is required to restore its original activity and adsorption capacity. Regeneration methods are mainly divided into two categories: physical method and chemical method. Thermal regeneration is the most widely used and most mature adsorption material regeneration method in industry. This method increases the vibration energy of the adsorbate molecules by external heating and increasing the temperature, so that the adsorption equilibrium relationship changes, and the adsorbate is desorbed or thermally decomposed from the adsorbent 300. Specifically, thermal regeneration includes steps such as drying, roasting and high-temperature desorption. Drying is to dry the adsorbent 300 at a low temperature to remove moisture and some volatile organic matter from the surface and pores of the adsorbent 300. Roasting is carried out at a high temperature to crack or oxidize the pollutants at a high temperature to achieve desorption. High-temperature desorption is to contact the adsorbent 300 with an inert gas (such as nitrogen or a rare gas) under high temperature conditions to desorb pollutants. The chemical regeneration method is to react the adsorbent 300 with a specific solvent or reagent to destroy the binding force between the adsorbent 300 and the target substance, so as to desorb, purify or recover it. This method includes chemical reactions such as hydrolysis, oxidation and reduction. For example, the wet oxidation regeneration method is a process in which the adsorbed organic matter is oxidized under high temperature and high pressure conditions using oxygen in the air, which is suitable for the regeneration of the powdered adsorbent 300.

[0067] Example: Adsorbent 300 of copper salt supported on silica.

[0068] Preparation and pretreatment of adsorbent 300: Fumed silica is selected as the basic adsorbent 300, and its particle size is 28-200 mesh. The silica adsorbent 300 is impregnated in CuCl 2 After 24 hours in the saturated solution, the loading amount is controlled to be 2% to 5% of the mass of the adsorbent 300. In a helium atmosphere, the impregnated adsorbent 300 is heated at 500°C for 2 hours to ensure that the water in the adsorbent 300 is completely removed and the copper is reduced from +2 valence to 0 valence.

[0069] Temperature control of adsorption column 100: Langmuir isotherm model is used to describe the adsorption behavior of the adsorbent on boron and phosphorus impurities in trichlorosilane: , in, is the adsorption capacity per unit adsorbent (mg / g), is the saturated adsorption capacity of the adsorbent (mg / g), is the adsorption equilibrium constant, which changes with temperature. is the impurity concentration in the adsorption column (mg / L), the adsorption equilibrium constant Affected by temperature, expressed as: , in, is the initial value of the adsorption constant (L / mol), is the adsorption enthalpy change (kJ / mol), usually a negative value, is the gas constant, is the absolute temperature in the adsorption column (K), which indicates the adsorption capacity of the adsorbent for boron and phosphorus impurities. Increase, adsorption performance improves, when the temperature is too high decreases, the selectivity of the adsorbent becomes worse.

[0070] The optimum adsorption temperature of the adsorbent 300 is set to 40° C., and the temperature is controlled by circulating the medium through the jacket 200 .

[0071] When the temperature needs to be raised, the second branch pipeline 201b and the fourth branch pipeline 202b are opened, the first branch pipeline 201a and the third branch pipeline 202a are closed, and the heat medium flow is adjusted by the regulating valve to raise the temperature to 40°C.

[0072] When cooling is required, the first pipe 201a and the third pipe 202a are opened, the second pipe 201b and the fourth pipe 202b are closed, and the refrigerant is circulated to reduce the temperature to 40°C.

[0073] Pressure control of adsorption column 100: The pressure control range is set at 1.0 MPaG to maintain the stability of the adsorbent 300 bed. The adsorption rate is determined by the following relationship: , in, is the adsorption rate, which indicates the amount of boron and phosphorus impurities removed from MPaG silicon trichlorohydrogen by the adsorbent per unit time. is the adsorption rate constant, is the operating pressure, To balance the pressure, it is expressed as: , in, is the initial equilibrium pressure, the operating pressure P is in the range of 0.5~1.5 MPaG, and the adsorption rate To achieve the best, when the pressure is too low, the adsorption rate slows down; when the pressure is too high, the energy consumption increases significantly.

[0074] Adsorption column 100 flow control: The control equation for impurity mass transfer in the adsorption column is expressed as: , in, For time, is the velocity vector of the fluid, is the concentration gradient, which indicates the rate of change of impurity concentration in space. is the diffusion coefficient, which indicates the molecular diffusion capacity of impurities in the fluid. The flow rate through the adsorption column 100 is controlled at 1.0 m³ / h to ensure that the fluid and the adsorbent 300 have sufficient contact time to achieve the best adsorption effect.

[0075] Comprehensive adsorption capacity , adsorption rate and energy consumption , build a multi-objective optimization model: , , in, is the weight factor of adsorption amount per unit adsorbent, is the adsorption rate weight factor, is the energy consumption weight factor, is the total energy consumption during the operation of the adsorption column, is the energy consumption coefficient related to temperature control, is the energy consumption coefficient related to pressure regulation, is the temperature of the jacket cold / heat medium, is the temperature of the fluid in the adsorption column, is the operating pressure of the adsorption column; based on the multi-objective optimization model, the temperature and pressure ranges are optimized under different conditions to achieve a balance between adsorption efficiency and energy consumption.

[0076] Case 1: The primary goal is to efficiently remove boron and phosphorus impurities. In this case, the adsorption capacity Weight Higher adsorption rate and energy consumption The weight is relatively low, optimizing the adsorption capacity, The conditions for maximization are: ,Right now and Larger, temperature range: -30℃ is better (at this time Maximum) operating pressure: Maintain at 0.5MPaG, because the adsorption capacity has no direct relationship with the pressure, control energy consumption, by adjusting the jacket refrigerant temperature make sure , while reducing the temperature difference energy consumption, the optimal parameters are: ( 0.5MPaG), suitable for process scenarios with extremely high boron and phosphorus removal rates.

[0077] Case 2: Adsorption rate is the key target. When the process requires a large flow rate and a short processing time, the adsorption rate Weight Higher adsorption capacity and energy consumption The weight is relatively low, optimizing the adsorption rate, Maximization conditions: Increase value, while reducing , Affected by temperature: Low temperature Smaller, damage pressure: Select MPaG upper limit, temperature selection: slightly higher than -30℃ (such as ), while maintaining The optimal parameters are: 1.5MPaG), suitable for large-scale industrial scenarios with high flow rate processing.

[0078] Case 3: Minimum energy consumption is the core goal. If the process is sensitive to energy consumption and production costs need to be significantly reduced, energy consumption Weight Higher adsorption capacity and adsorption rate The weight is relatively low, reducing the energy consumption of temperature control. Temperature selection: close to , reduce temperature difference , reduce the energy consumption of pressure maintenance: select the lowest value of operating pressure MPaG, comprehensive performance evaluation: and Slightly decreased, but met the basic boron and phosphorus removal rate, the optimal parameters are: ( 0.5MPaG), suitable for application scenarios with extremely high requirements for energy consumption control.

[0079] In the operation of the adsorption column 100, the trichlorosilane feedstock contains boron and phosphorus impurities, which enter the column through the feed pipe 201 located at the lower end of the adsorption column 100. Here, the trichlorosilane comes into contact with the copper salt-loaded silica adsorbent 300 filled in the column. The copper salt adsorbent 300 is effective because it contains copper ions (such as Cu 2+), these copper ions can form complexes with boron and phosphorus impurities in trichlorosilane to achieve selective adsorption. This adsorption effect depends on the formation of coordination bonds between the exposed metal sites in the copper salt and the impurities. In addition, the copper salt is loaded on silica, and the optimization of this physical structure increases the specific surface area of ​​the adsorbent 300, provides more active sites, thereby increasing the contact area between trichlorosilane and the adsorbent 300 and enhancing the ability to remove phosphorus impurities. Under controlled temperature and pressure, this characteristic of the copper salt adsorbent 300 is particularly prominent. For example, at the optimal adsorption temperature of 40°C, the copper salt-loaded adsorbent 300 can react more effectively with impurities in trichlorosilane to achieve efficient selective adsorption. The adsorption efficiency of copper salts is also affected by their physical structure, including the size and distribution of particles, which determine the contact efficiency between the adsorbent 300 and the impurities in trichlorosilane. Therefore, in the entire adsorption process, by precisely controlling the temperature, pressure and flow rate, the performance of the copper salt adsorbent 300 can be optimized to ensure the high purity of trichlorosilane.

[0080] Product collection: The high-purity trichlorosilane that has undergone adsorption treatment flows out through the high-purity trichlorosilane product discharge pipe 104 at the upper end and enters the subsequent storage or use link.

[0081] Pressure control and safety release: A safety release pipe 103 is provided at the upper end of the adsorption column 100 to release the pressure when the system pressure exceeds 1.0 MPaG to protect the safety of equipment and operators.

[0082] Drainage and regeneration of the adsorbent 300: The drain pipe 101 at the bottom of the adsorption column 100 is used to regularly discharge waste and impurities captured by the adsorbent 300 to maintain the working efficiency of the adsorption column 100.

[0083] The copper salt-loaded adsorbent 300 on silicon dioxide can be regenerated by a thermal regeneration method after adsorbing the boron and phosphorus impurities in trichlorosilane. The specific operation steps may include heating the adsorbent 300 to a certain temperature to desorb or decompose the adsorbed boron and phosphorus impurities, and then recovering the released target substance through purification equipment. This method is suitable for situations where the target substance is relatively stable at high temperatures, and can effectively restore the adsorption capacity of the copper salt adsorbent 300. In this way, the copper salt adsorbent 300 can be repeatedly used in the cycle of adsorption and regeneration, extending its service life and reducing processing costs.

[0084] Monitoring and control: Thermometers and pressure transmitters are arranged at different positions of the adsorption column 100 to monitor the process status inside the adsorption column 100 and ensure that the adsorption process is carried out under optimal conditions.

[0085] Importantly, it should be noted that the construction and arrangement of the present application shown in a plurality of different exemplary embodiments are only exemplary. Although only a few embodiments are described in detail in this disclosure, it should be easily understood by the personnel referring to this disclosure that many modifications are possible (e.g., the size, scale, structure, shape and ratio of various elements, and parameter values ​​(e.g., temperature, pressure, etc.), installation arrangement, use of materials, color, directional changes, etc.) without substantially departing from the novel teachings and advantages of the subject matter described in the application. For example, the element shown as integrally formed can be composed of multiple parts or elements, the position of the element can be inverted or otherwise changed, and the nature or number or position of the discrete element can be changed or changed. Therefore, all such modifications are intended to be included in the scope of the present invention. The order or sequence of any process or method steps can be changed or reordered according to alternative embodiments. Therefore, the present invention is not limited to a specific embodiment, but extends to a variety of modifications that still fall within the scope of the appended claims.

[0086] Additionally, in order to provide a concise description of exemplary embodiments, all features of an actual embodiment may not be described (ie, those features that are not relevant to the best mode presently contemplated for carrying out the invention or those features that are not relevant to implementing the invention).

[0087] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A device for removing boron and phosphorus impurities from trichlorosilane, characterized in that: include, An adsorption column (100) for adsorbing trichlorosilane, wherein an adsorbent (300) is installed inside the adsorption column (100), and the adsorbent (300) is specifically used to remove boron and phosphorus impurities in trichlorosilane, the adsorbent (300) in the adsorption column (100) is arranged in multiple sections, and each section of the adsorbent (300) is fixed by a supporting structure and a pressing structure, and a plurality of temperature sensors (400) are arranged on the adsorption column (100), and the plurality of temperature sensors (400) correspond to each section of the adsorbent (300), and are arranged in sequence along the vertical direction; A jacket (200) is arranged on the outer wall of the adsorption column (100) and is used to control the temperature inside the adsorption column (100). The pipeline connected to the jacket (200) is divided into an inlet and an outlet, and both are provided with a regulating valve and a shut-off valve for controlling the medium and flow rate entering the jacket.

2. The equipment for removing boron and phosphorus impurities from trichlorosilane according to claim 1, characterized in that: The adsorbent (300) is an ion exchange resin containing an amine, or a chelate resin, or an aluminum gel, or an adsorbent loaded with copper salts, or an adsorbent (300) containing halogen elements, or a siloxane.

3. The device for removing boron and phosphorus impurities from trichlorosilane according to claim 1 or 2, characterized in that: The jacket (200) can use circulating water, steam condensate, seven-degree water, ethylene glycol with different concentration ratios or temperatures, etc. to increase or decrease the temperature of the material.

4. The equipment for removing boron and phosphorus impurities from trichlorosilane according to claim 1, characterized in that: The bottom of the adsorption column (100) is provided with a sewage pipe (101), a trichlorosilane feed pipe (102) containing boron and phosphorus impurities is provided at the lower end of the side, and a safety discharge pipe (103) and a high-purity trichlorosilane product discharge pipe (104) are provided at the upper end.

5. The equipment for removing boron and phosphorus impurities from trichlorosilane according to claim 1, characterized in that: A feed pipe (201) is provided at the upper end of the jacket (200), and a discharge pipe (202) is provided at the lower end; two branch pipes, a refrigerant pipe and a heat medium pipe, are separated from the ends of the feed pipe (201) and the discharge pipe (202); regulating valves are provided on the main pipes of the feed pipe (202) and the discharge pipe (202), and shut-off valves are provided on each branch pipe.

6. A method for removing boron and phosphorus impurities from trichlorosilane, characterized in that: The device for removing boron and phosphorus impurities from trichlorosilane according to any one of claims 1 to 5, and the following steps: The trichlorosilane material containing boron and phosphorus is transported to the bottom of the adsorption column; Boron and phosphorus impurities are adsorbed by adsorbents to obtain high-purity trichlorosilane, which is exported from the top of the equipment; The temperature and pressure inside the adsorption column are controlled to maintain optimal adsorption conditions.

7. The method for removing boron and phosphorus impurities from trichlorosilane according to claim 6, characterized in that: The temperature control range of the adsorption column is between -30°C and 80°C, the pressure control range is between 0.5 and 1.5 MPaG, and the flow rate flowing through the adsorption column is controlled between 0.2 and 3 m³ / h.

8. The method for removing boron and phosphorus impurities from trichlorosilane according to claim 6 or 7, characterized in that: The method also includes restoring the adsorption capacity of the adsorbent through a regeneration process after the adsorption of the adsorbent reaches saturation, wherein the regeneration process is thermal regeneration or chemical regeneration.

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