A system and method for removing organics from trichlorosilane

Abstract

The present application relates to the technical field of building structure, and particularly relates to a system for removing organic matter in trichlorosilane, which comprises: a rectification main tower for preliminarily separating different components in raw materials to generate a device with two flow outlets of tower top and tower kettle; an adsorption device for accepting liquid phase reflux part from the tower top of the rectification main tower and gas phase components of the tower kettle to catalytically convert methyl dichlorosilane into methyl trichlorosilane; and an online GC monitoring system for monitoring the composition of the reflux components of the tower top in real time and adjusting the proportion of gas phase silicon tetrachloride in the adsorption device according to the monitoring result. Through the present application, the problem of low removal efficiency of organic matter in the production process of trichlorosilane is effectively solved, the combination of rectification exclusion and the adsorption device can more completely remove methyl dichlorosilane with close boiling points, the chemical reaction conditions are optimized, the conversion efficiency of organic matter is improved, the production cost is reduced, and the product quality is improved.

Description

Technical Field

[0001] This invention relates to the field of chemical purification technology, specifically to a system and method for removing organic matter from trichlorosilane. Background Technology

[0002] In the production of electronic-grade polysilicon, trichlorosilane is an important raw material, and its purity and composition directly affect the quality of the product. Existing technologies mainly remove organic matter from trichlorosilane through distillation. However, for methyldichlorosilane, which has a boiling point close to that of trichlorosilane, distillation cannot achieve complete removal, and a large amount of methyl carbonaceous organic matter remains in the system. Existing processes have also added adsorption devices, utilizing the adsorption and conversion function of resin to chemically react methyldichlorosilane with tetrachlorosilane to generate methyltrichlorosilane with a higher boiling point, which is then separated and removed in the subsequent distillation system. However, the required reaction concentration is determined solely by the flow rate ratio entering the resin, which cannot guarantee sufficient contact between the reactants, resulting in low conversion efficiency. Furthermore, to ensure reaction time, a large adsorption device is required, increasing production costs.

[0003] The information disclosed in this background section is intended only to enhance the understanding of the general background of this disclosure and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0004] This invention provides a system and method for removing organic matter from trichlorosilane, thereby effectively solving the problems pointed out in the background art.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A system for removing organic matter from trichlorosilane includes: A distillation column is a device used to initially separate different components in a feedstock, producing two outlets: the top and the bottom of the column. The adsorption unit accepts the liquid reflux portion from the top of the main distillation column and the gas phase component from the bottom of the column, and catalytically converts methyldichlorosilane into methyltrichlorosilane. An online GC monitoring system is used to monitor the composition of the top reflux components in real time and adjust the proportion of gaseous silicon tetrachloride in the adsorption unit based on the monitoring results.

[0006] Furthermore, the system also includes: A liquid phase cutting device is used to cut a portion of the liquid phase from the reflux liquid as the liquid phase input of the adsorption device, thereby maintaining the operation of the adsorption device and the catalytic conversion reaction.

[0007] Furthermore, the system also includes: A condenser is used to condense the gaseous components in the reflux liquid at the top of the main distillation column, recovering and partially using it as reflux or raw material for the next process. Pressure control devices control the pressure within the system to maintain the normal operation of each device and the stability of reaction conditions.

[0008] Furthermore, the online GC monitoring system includes: GC instruments are used to analyze and monitor the components of effluents; The sample inlet is used to introduce the sample into the GC analysis system; A detector used to detect and measure the relative concentration of various compounds in a sample; A data processing system, used to collect, analyze, and display monitoring results, is connected to the adsorption device and adaptively controls the reaction process.

[0009] Furthermore, the online GC monitoring system uses a feedback control model for logic control, including: The sensor is used to monitor the content of methyl dichloro component in the reflux component at the top of the column in real time and transmit the data to the control system. The controller is used to receive data from the sensor, compare it with a preset target value, and calculate the corresponding control signal. An actuator is used to receive control signals sent by the controller and adjust the tetrachloride ratio in the column reactor according to the signals to ensure that the mass ratio of tetrachloride in the total reflux component reaches the set standard. The controller and the actuator constitute the control system. The feedback path is used to transmit the real-time data measured by the sensor to the controller, forming a feedback control loop. The controller makes real-time adjustments based on the data transmitted from the feedback path. The logic control algorithm processes sensor data and makes judgments and decisions based on preset logic conditions.

[0010] Furthermore, the logic control algorithm is a model predictive control algorithm.

[0011] Further, the adsorption device includes: An adsorption column is used to contain adsorption resin and enable the conversion reaction of carbon-containing organic matter. Heat exchangers are used to control the temperature inside the adsorption unit; The feed inlet is used to receive the liquid reflux component from the top of the main distillation column and the gaseous component from the bottom of the column; The discharge port is used to output the product after the reaction process. A regulating valve and flow meter control device are used to control the flow rate of feed and discharge, and are connected to the online GC monitoring system.

[0012] Furthermore, the resin device in the adsorption column is a separately isolated structure.

[0013] Furthermore, the reboiler of the main distillation column includes a reboiler output pipe, and the reboiler output pipe is of U-shaped type.

[0014] A method for removing organic matter from trichlorosilane includes: The original mixture is processed by distillation to separate the light and heavy components; The separated light components are refluxed back to the main distillation column as reaction feed and liquid phase input to the adsorption unit; An adsorption device is used to carry out a gas-liquid phase contact reaction to convert organic matter into harmless compounds. A monitoring model based on logic control algorithms is used to monitor the reaction process in real time and adjust the reaction conditions.

[0015] The technical solution of this invention can achieve the following technical effects: It effectively solves the problem of low organic matter removal efficiency in the production of trichlorosilane. The combination of distillation and adsorption devices can more thoroughly remove methyldichlorosilane with a boiling point close to that of trichlorosilane. At the same time, it optimizes the chemical reaction conditions, improves the organic matter conversion efficiency, reduces production costs, and improves product quality. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 A schematic diagram of a system for removing organic matter from trichlorosilane; Figure 2 This is a schematic flowchart of a method for removing organic matter from trichlorosilane. Detailed Implementation

[0018] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0019] Unless otherwise defined, 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. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0020] Example 1 like Figure 1 As shown, the present invention provides a system for removing organic matter from trichlorosilane, comprising: A distillation column is a device used to initially separate different components in a feedstock, producing two outlets: the top and the bottom of the column. Specifically, the main distillation column is one of the core components of the system, used to initially separate the different components in the feedstock. The feedstock mixture, containing organic matter, silicon tetrachloride, and other light components, enters the main distillation column. Inside the column, the feedstock mixture is heated, causing its components to separate according to their boiling points, resulting in two outlets: the top outlet and the bottom outlet. The top outlet mainly contains lighter components, typically trichlorosilane containing light components (such as methyldichlorosilane), while the bottom outlet contains heavier components.

[0021] The adsorption unit accepts the liquid reflux portion from the top of the main distillation column and the gas phase component from the bottom of the column, and catalytically converts methyldichlorosilane into methyltrichlorosilane. Specifically, the adsorption unit is a crucial device for further processing the products of the main distillation column. It receives the liquid reflux from the top of the main distillation column and the gaseous components from the bottom. Within the adsorption unit, organic compounds such as methyldichlorosilane undergo catalytic conversion to more easily processed compounds like methyltrichlorosilane, thereby improving the removal efficiency of organic matter. Simultaneously, due to the coupling effect of distillation, the gas and liquid phases within the column undergo sufficient heat exchange and contact within the adsorption unit. Through the catalytic conversion of the resin, the conversion reaction of carbonaceous organic compounds is completed, forming a novel reactive distillation system, thus improving the quality of the trichlorosilane feedstock.

[0022] An online GC monitoring system is used to monitor the composition of the top reflux components in real time and adjust the proportion of gaseous silicon tetrachloride in the adsorption unit based on the monitoring results.

[0023] Specifically, the online GC monitoring system is a key component for real-time monitoring of the composition of the reflux component at the top of the distillation main column. It analyzes the reflux component using gas chromatography (GC) to determine its composition and content. Based on the monitoring results, the proportion of gaseous silicon tetrachloride in the adsorption unit can be adjusted, thereby optimizing system operation and improving the efficiency of organic matter removal.

[0024] This invention effectively solves the problem of low organic matter removal efficiency in the production of trichlorosilane. The combination of distillation and adsorption devices can more thoroughly remove methyldichlorosilane with a boiling point close to that of trichlorosilane. At the same time, it optimizes the chemical reaction conditions, improves the organic matter conversion efficiency, reduces production costs, and improves product quality.

[0025] As a preferred embodiment of the above, the system further includes: The liquid phase cutting device is used to cut a portion of the liquid phase from the reflux liquid as the liquid phase input of the adsorption device, thereby maintaining the operation of the adsorption device and the catalytic conversion reaction.

[0026] Specifically, the liquid phase cut-off device ensures a constant sufficient liquid phase input to the adsorption unit, thus maintaining its normal operation and contributing to system stability and continuity. Furthermore, the liquid phase cut-off device cuts off a portion of the liquid phase from the reflux liquid and feeds it into the adsorption unit. This liquid phase contains organic matter awaiting further processing, providing the necessary feedstock for the catalytic conversion reaction within the adsorption unit. By ensuring a constant sufficient liquid phase input to the adsorption unit, the liquid phase cut-off device helps optimize system operating efficiency. It ensures an adequate supply of reactants, thereby improving the efficiency of the catalytic conversion reaction and the purity of the products.

[0027] As a preferred embodiment of the above, the system further includes: A condenser is used to condense the gaseous components in the reflux liquid at the top of the main distillation column, recovering and partially using it as reflux or raw material for the next process. Pressure control devices control the pressure within the system to maintain the normal operation of each device and the stability of reaction conditions.

[0028] Specifically, a condenser is a device used to condense the gaseous components in the reflux liquid at the top of the main distillation column. It lowers the temperature of the gaseous components, condensing them into a liquid so that they can be recovered and partially used as reflux or feedstock for the next process. The role of the condenser is to improve recovery rates and reduce resource waste. A pressure control device is used to control the pressure within the system to maintain the normal operation of each unit and the stability of reaction conditions. By monitoring and adjusting the pressure within the system, the pressure control device can ensure the balance between the components and optimize reaction conditions to improve system efficiency and product quality.

[0029] As a preferred embodiment of the above, the online GC monitoring system includes: GC instruments are used to analyze and monitor the components of effluents; The sample inlet is used to introduce the sample into the GC analysis system; A detector used to detect and measure the relative concentration of various compounds in a sample; The data processing system is used to collect, analyze, and display monitoring results. It is connected to the adsorption device and adaptively controls the reaction process.

[0030] Specifically, the GC instrument is a key device for analyzing and monitoring the components of the effluent. Using gas chromatography, it effectively separates and detects different components in a sample, providing detailed information about the sample composition and relative concentrations. The injection port is the interface device connecting the sample and the GC analysis system. It introduces the sample to be analyzed into the GC system for subsequent analysis and monitoring. The design and operation of the injection port can affect the sample injection rate and accuracy, thus affecting the accuracy of the monitoring results. The detector is one of the key components of the GC system, used to detect and measure the relative concentrations of various compounds in the sample. It can quantitatively analyze different components in the sample and convert the analytical results into electrical signals for subsequent data processing. The data processing system collects, analyzes, and displays the monitoring results and connects to the adsorption unit to achieve adaptive control of the reaction process. This system can process the data output from the GC instrument in real time and adjust the proportion of gaseous silicon tetrachloride in the adsorption unit according to the monitoring results, thereby optimizing the reaction conditions and improving the organic matter removal efficiency.

[0031] As a preferred embodiment of the above, the online GC monitoring system performs logic control based on a feedback control model, including: The sensor is used to monitor the content of methyl dichloro component in the reflux component at the top of the column in real time and transmit the data to the control system. The controller is used to receive data from the sensors, compare it with preset target values, and calculate the corresponding control signals. The actuator is used to receive control signals sent by the controller and adjust the tetrachloride ratio in the tower bottom according to the signals to ensure that the mass ratio of tetrachloride in the total reflux component reaches the set standard. The controller and the actuator constitute the control system. The feedback path is used to transmit the real-time data measured by the sensor to the controller, forming a feedback control loop. The controller makes real-time adjustments based on the data transmitted from the feedback path. The logic control algorithm processes sensor data and makes judgments and decisions based on preset logic conditions.

[0032] Specifically, through sensor monitoring, the system can acquire real-time data on the composition and content of the reflux components, providing accurate reference for subsequent control. The controller, based on the sensor data and preset logical conditions, makes judgments and calculations to generate corresponding control signals to adjust the system's operation. The actuator executes the commands sent by the controller, adjusting the operating parameters in the adsorption device to achieve real-time system control. The feedback path transmits real-time data measured by the sensors to the controller, forming a feedback control loop. Through the feedback path, the controller can acquire real-time system status information and make real-time adjustments based on this information, achieving adaptive control of the system operation. The logic control algorithm is a key component that processes sensor data and makes judgments and decisions based on preset logical conditions. This algorithm, based on the real-time data monitored by the sensors and combined with preset logical conditions, evaluates the system's status and provides operational guidance, offering a reasonable control strategy for the system's operation.

[0033] As a preferred embodiment of the above, the logic control algorithm is a model predictive control algorithm.

[0034] Specifically, firstly, a dynamic mathematical model of the trichlorosilane removal system is established based on the system's physical characteristics and operational rules. This model describes the relationships between the various components of the system, including the distillation column, adsorption unit, online GC monitoring system, and their interactions with the external environment. Based on the established dynamic model, the MPC algorithm is used to predict the system state at future moments. By considering possible operational scenarios and external disturbances over a period of time, the system's response and performance are predicted. Based on the prediction, the MPC algorithm solves an optimization problem to calculate the optimal control strategy at the current moment. The goal of this optimization problem is to optimize the system's performance indicators at future moments, while also considering the system's constraints and operational limitations. According to the optimal control strategy calculated by the MPC algorithm, corresponding control operations are implemented, and the actual operation of the system is monitored. Simultaneously, feedback information from the system, such as sensor data, is collected in real time to update the model and adjust the control strategy. As the system evolves and the external environment changes, the MPC algorithm continuously optimizes and adjusts the control strategy to ensure that the system always operates in an optimal state and achieves efficient removal of trichlorosilane organic compounds.

[0035] As a preferred embodiment of the above, the adsorption device includes: An adsorption column is used to contain adsorption resin and enable the conversion reaction of carbon-containing organic matter. Heat exchangers are used to control the temperature inside the adsorption unit; The feed inlet is used to receive the liquid reflux component from the top of the main distillation column and the gaseous component from the bottom of the column; The discharge port is used to output the product after the reaction process. The regulating valve and flow meter control device are used to control the flow rate of feed and discharge, and are connected to the online GC monitoring system.

[0036] Specifically, the adsorption column is a device used to contain adsorption resin. Through its internal structure and packing design, it enables the conversion reaction of carbon-containing organic matter. Inside the adsorption column, the adsorption resin contacts and reacts with the flowing liquid reflux component and gaseous component, completing the catalytic conversion of methyldichlorosilane to methyltrichlorosilane. A heat exchanger is used to control the temperature inside the adsorption unit. By adjusting the operating parameters of the heat exchanger, the temperature inside the adsorption column can be maintained within a suitable range, promoting the catalytic conversion reaction. The feed inlet receives the liquid reflux component from the top of the distillation column and the gaseous component from the bottom of the column. These feeds enter the adsorption unit through the feed inlet, contacting and reacting with the adsorption resin to complete the conversion of methyldichlorosilane to methyltrichlorosilane. The discharge outlet outputs the products after the reaction. After the catalytic conversion reaction in the adsorption unit, the products such as methyltrichlorosilane are discharged from the discharge outlet and used as part of the feed for the distillation column for further separation and purification. The regulating valve and flow meter control device are used to control the feed and discharge flow rates and are connected to the online GC monitoring system. Through these devices, the feed and discharge flow rates in the adsorption unit can be precisely adjusted to maintain the stable operation of the system and to achieve data interaction and control coordination with the online GC monitoring system.

[0037] As a preferred embodiment of the above, the resin device in the adsorption column is a separately isolated structure.

[0038] Specifically, the resin unit in the adsorption column adopts a separate isolation structure. This means the adsorption column is independently placed within the system and appropriate isolation measures are taken to ensure its independence from other units and prevent mutual interference. This design effectively reduces the impact of the resin unit on the cleanliness of the main distillation column and avoids the influence of resin use on system pressure drop and fluid flow, thereby improving system stability and reaction efficiency. Simultaneously, the separate isolation structure facilitates the maintenance and repair of the adsorption column, contributing to the long-term stable operation and management of the system.

[0039] As a preferred embodiment of the above, the reboiler of the main distillation column includes a reboiler output pipe, and the reboiler output pipe is of U-shaped type.

[0040] Specifically, the reboiler output pipe is designed with a U-shaped tube. This structure can effectively ensure that the output fluid is in the gas phase, thereby ensuring stable operation and transmission of the fluid. In addition, the U-shaped tube design can effectively reduce the pressure loss of the fluid and has good pressure resistance, making the system operation more stable and reliable. At the same time, the U-shaped tube structure of the reboiler output pipe also helps to avoid liquid accumulation and scaling inside the pipe, reducing the workload of pipe cleaning and maintenance, and improving the service life and maintenance efficiency of the system.

[0041] Example 2 Based on the same inventive concept as the organic matter removal system in trichlorosilane described in the foregoing embodiments, the present invention also provides a method for removing organic matter from trichlorosilane, such as... Figure 2 As shown, the method includes: The original mixture is processed by distillation to separate the light and heavy components; The separated light components are refluxed back to the main distillation column as reaction feed and liquid phase input to the adsorption unit. An adsorption device is used to carry out a gas-liquid phase contact reaction to convert organic matter into harmless compounds. A monitoring model based on logic control algorithms is used to monitor the reaction process in real time and adjust the reaction conditions.

[0042] The removal method described above in this invention can be effectively applied to the removal system of organic matter in trichlorosilane, and the technical effects it can achieve are as described in the above embodiments, and will not be repeated here.

[0043] Although this application has been described in conjunction with specific features and embodiments, it is obvious that various modifications and combinations can be made thereto without departing from the spirit and scope of this application. Accordingly, this specification and drawings are merely exemplary illustrations of the application as defined herein, and are to be considered as covering any and all modifications, variations, combinations, or equivalents within the scope of this application. Clearly, those skilled in the art can make various alterations and modifications to this application without departing from its scope. Thus, if such modifications and modifications fall within the scope of this application and its equivalents, this application intends to include such modifications and modifications.

Claims

1. A system for removing organics from trichlorosilane, comprising: include: The main distillation column is a device that performs preliminary separation on chlorosilanes containing organic matter, silicon tetrachloride and other light components that enter the main distillation column, producing two outlets: the top of the column and the bottom of the column. The adsorption unit accepts the liquid reflux portion from the top of the main distillation column and the gas phase components from the bottom of the column; The adsorption device includes an adsorption column for containing adsorption resin to realize the conversion reaction of carbon-containing organic matter; Inside the adsorption column, the adsorption resin comes into contact with and reacts with the flowing liquid reflux component and gaseous component, completing the catalytic conversion of methyldichlorosilane to methyltrichlorosilane. A liquid phase cutting device is used to cut a portion of the liquid phase from the reflux liquid as the liquid phase input of the adsorption device, thereby maintaining the operation of the adsorption device and the catalytic conversion reaction. An online GC monitoring system is used to monitor the composition of the reflux components at the top of the column in real time and adjust the proportion of gaseous silicon tetrachloride in the adsorption unit according to the monitoring results. The online GC monitoring system is based on a feedback model for logic control, and the logic control algorithm is a model predictive control algorithm.

2. The organic matter removal system from trichlorosilane according to claim 1, characterized in that, The system also includes: A condenser is used to condense the gaseous components in the reflux liquid at the top of the main distillation column, recovering and partially using it as reflux or raw material for the next process. Pressure control devices control the pressure within the system to maintain the normal operation of each device and the stability of reaction conditions.

3. The organic matter removal system from trichlorosilane according to claim 1, characterized in that, The online GC monitoring system includes: GC instruments are used to analyze and monitor the components of effluents; The sample inlet is used to introduce the sample into the GC analysis system; A detector used to detect and measure the relative concentration of various compounds in a sample; A data processing system, used to collect, analyze, and display monitoring results, is connected to the adsorption device and adaptively controls the reaction process.

4. The organic matter removal system from trichlorosilane according to claim 1, characterized in that, The adsorption device includes: Heat exchangers are used to control the temperature inside the adsorption unit; The feed inlet is used to receive the liquid reflux component from the top of the main distillation column and the gaseous component from the bottom of the column; The discharge port is used to output the product after the reaction process. A regulating valve and flow meter control device are used to control the flow rate of feed and discharge, and are connected to the online GC monitoring system.

5. The organic matter removal system for trichlorosilane according to claim 4, characterized in that, The resin device in the adsorption column is a separately isolated structure.

6. The organic matter removal system from trichlorosilane according to claim 1, characterized in that... The reboiler of the main distillation column includes a reboiler output pipe, and the reboiler output pipe is of U-shaped type.

7. A method for removing organic matter from trichlorosilane, characterized in that, The system for removing organic matter from trichlorosilane as described in any one of claims 1-6 comprises: The original mixture is processed by distillation to separate the light and heavy components; The separated light components are refluxed back to the main distillation column as reaction feed and liquid phase input to the adsorption unit; An adsorption device is used to carry out a gas-liquid phase contact reaction to convert organic matter into harmless compounds. A monitoring model based on logic control algorithms is used to monitor the reaction process in real time and adjust the reaction conditions.

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