Separation device for removing carbonaceous organic matter from trichlorosilane.

Abstract

This utility model relates to the technical field of trichlorosilane purification, and in particular to a separation device for removing carbon-containing organic matter from trichlorosilane, comprising: a condenser for condensing gaseous chlorosilane into liquid chlorosilane; a separator having a partition dividing the separator into a first chamber and a second chamber, the bottom end of the partition being detached from the bottom of the separator; the top of the first chamber being connected to an inlet for liquid chlorosilane and an inlet for carrier gas; adsorption components being provided in both the bottom to middle region of the first chamber and the bottom to top region of the second chamber; and the top of the second chamber being connected to an outlet for purified chlorosilane to flow out. By employing static and dynamic adsorption, the device can comprehensively remove carbon-containing compounds from trichlorosilane, improve product purity, and ensure the quality of electronic-grade polycrystalline silicon rods.

Description

Technical Field

[0001] This utility model relates to the technical field of trichlorosilane purification, and in particular to a separation device for removing carbon-containing organic matter from trichlorosilane. Background Technology

[0002] As the main raw material for the production of electronic-grade polysilicon, the impurity content in trichlorosilane directly affects the product grading of electronic-grade polysilicon.

[0003] In existing technologies, after liquid chlorosilane is processed by a separation tower, trichlorosilane containing carbon compounds is discharged from the top of the tower, and silicon tetrachloride is discharged from the bottom of the tower. Among them, trichlorosilane containing carbon compounds is mostly processed by dynamic adsorption. Most devices adopt a simple top-in-bottom-out or bottom-in-top-out flow channel design, which results in a short residence time and uneven distribution in the adsorption chamber. This causes some carbon-containing organic matter to fail to make sufficient contact with the adsorbent and is difficult to be effectively adsorbed. As a result, carbon deposits of varying degrees appear on the downstream polycrystalline silicon rods, which seriously affects the quality performance of polycrystalline silicon. Utility Model Content

[0004] To solve the above-mentioned technical problems, this utility model provides a separation device for removing carbon-containing organic matter from trichlorosilane. It adopts static adsorption and dynamic adsorption, which can completely remove carbon-containing compounds from trichlorosilane, improve product purity, and ensure the product quality of electronic-grade polycrystalline silicon rods.

[0005] This utility model discloses a separation device for removing carbon-containing organic matter from trichlorosilane, comprising: A condenser is used to condense gaseous chlorosilanes into liquid chlorosilanes. The separator has a partition that divides it into a first chamber and a second chamber, with the bottom of the partition detached from the bottom of the separator. The top of the first chamber is connected to inlet one for liquid chlorosilane and inlet two for carrier gas. Adsorption components are provided in both the first chamber from bottom to middle and the second chamber from bottom to top. The top of the second chamber is connected to an outlet for the purified chlorosilane to flow out.

[0006] As a preferred embodiment of this utility model, the first chamber is connected to a level gauge.

[0007] In a preferred embodiment of this invention, the carrier gas is hydrogen.

[0008] As a preferred embodiment of this utility model, a differential pressure gauge is connected between the first chamber and the second chamber.

[0009] As a preferred embodiment of this utility model, the adsorption component is a filter element structure filled with adsorbent.

[0010] As a preferred embodiment of this invention, the adsorbent is a macroporous adsorption resin or a molecular sieve.

[0011] As a preferred embodiment of this utility model, the second chamber has an outlet 2 connected to its side for the flow of carrier gas.

[0012] As a preferred embodiment of this utility model, the hydrogen purity is ≥99.99%.

[0013] Compared with the prior art, the beneficial effects of this utility model are as follows: This device performs static adsorption simultaneously in two chambers under pressure balance, allowing chlorosilane to be fully wetted and statically contacted with the adsorption component, extending the adsorption time and improving the contact uniformity, thus more comprehensively removing carbon-containing organic matter; after static adsorption is completed, the pressure difference formed by the carrier gas pressurization drives the material flow for dynamic adsorption, utilizing the fluid flow characteristics to allow chlorosilane to fully interact with the adsorption component again. Through the combination of static deep adsorption and dynamic enhanced adsorption, the problem of insufficient contact between material and adsorbent and limited removal effect in traditional single adsorption methods is effectively solved, significantly improving the purification effect of trichlorosilane. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of this utility model; The following labels are used in the attached diagram: 1. Condenser; 2. Separator; 3. First chamber; 4. Second chamber; 5. Baffle; 6. Inlet 1; 7. Inlet 2; 8. Adsorption assembly; 9. Outlet 1; 10. Level gauge; 11. Differential pressure gauge; 12. Outlet 2. Detailed Implementation

[0015] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings.

[0016] Many specific details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0017] Example: Reference Figure 1 This embodiment provides a separation device for removing carbon-containing organic matter from trichlorosilane, comprising: Condenser 1 is used to condense gaseous chlorosilane into liquid chlorosilane; wherein the gaseous chlorosilane originates from the top of the separation tower and is trichlorosilane, a carbon-containing compound. The separator 2 is provided with a partition 5 that divides the separator 2 into a first chamber 3 and a second chamber 4. The bottom end of the partition 5 is detached from the bottom of the separator 2. The top of the first chamber 3 is connected to inlet 6 for liquid chlorosilane and inlet 7 for carrier gas. Adsorption components 8 are provided in both the first chamber 3 from the bottom to the middle region and the second chamber 4 from the bottom to the top region; The top of the second chamber 4 is connected to an outlet 9 for the purified chlorosilane to flow out.

[0018] The specific working process of this device is as follows: the chlorosilane containing carbon compounds is first condensed into a liquid state by condenser 1, and then enters the first chamber 3 of separator 2 from inlet 6. The carrier gas enters the first chamber 3 from inlet 7. In the static adsorption stage, the pressure of the first chamber 3 and the second chamber 4 is maintained in equilibrium through regulation. After liquid chlorosilane enters the first chamber 3 through inlet 6, it remains stationary due to the lack of pressure, and the liquid level stabilizes at a specific height, fully wetting the adsorption component 8 from the bottom to the middle area of ​​the first chamber 3. At the same time, since the pressure in the two chambers is equal, the chlorosilane in the first chamber 3 will not flow into the second chamber 4. The chlorosilane inside the second chamber 4 is also in a stationary state, fully contacting the adsorption component 8 from its bottom to the top area for static adsorption. Under pressure equilibrium, the two chambers maintain their static state, and the chlorosilane and the adsorption component 8 are in a fully wetted static contact state, working together to enhance the removal effect on carbonaceous organic matter. In the dynamic adsorption stage, after the static adsorption in the two chambers is completed, the pressure balance is broken by pressurizing the carrier gas. With the driving force generated by the pressurization of the carrier gas, the chlorosilane flows through the adsorption component 8. During the flow, the chlorosilane continuously contacts the adsorption component 8. Through the dynamic flushing and permeation of the fluid, it further interacts fully with the adsorption component 8 to complete the dynamic adsorption. This device performs static adsorption simultaneously in two chambers under pressure equilibrium, allowing chlorosilane to be fully wetted and in static contact with the adsorption component 8, extending the adsorption time and improving contact uniformity, thus enabling more comprehensive removal of carbon-containing organic matter. After static adsorption is completed, dynamic adsorption is performed by using the pressure difference formed by carrier gas pressurization to drive the material flow. The fluid flow characteristics allow chlorosilane to interact fully with the adsorption component 8 again. Through the combination of static deep adsorption and dynamic enhanced adsorption, the problem of insufficient contact between material and adsorbent and limited removal effect in traditional single adsorption methods is effectively solved, significantly improving the purification effect of trichlorosilane.

[0019] In some embodiments of this utility model, the first chamber 3 is connected to a level gauge 10; More specifically, the level gauge 10 can be a magnetic float level gauge 10, a glass tube level gauge 10, a radar level gauge 10, or a float level gauge 10, etc. The level gauge 10 can monitor the liquid chlorosilane level in the first chamber 3 in real time, which facilitates precise control of the liquid level during static adsorption, ensuring that the chlorosilane can fully wet the adsorption component 8 from the bottom to the middle area of ​​the first chamber 3. At the same time, by adjusting the liquid level, different adsorption times can be adapted to ensure stable static adsorption effect. In some embodiments of this invention, the carrier gas is hydrogen. More specifically, hydrogen is chemically stable and does not react with chlorosilanes or carbon-containing organic matter, thus not introducing new impurities. It can reliably drive the flow of chlorosilanes between chambers by creating a pressure difference through pressurization. At the same time, hydrogen has reducing properties, which can inhibit the decomposition or oxidation reactions of chlorosilanes that may occur due to local high temperatures or impurities, ensuring the stability of the material. In addition, it has a low density and is easy to separate, and can be subsequently separated and recovered from purified chlorosilanes through a simple process.

[0020] In some embodiments of this utility model, a differential pressure gauge 11 is connected between the first chamber 3 and the second chamber 4; More specifically, the differential pressure gauge 11 is installed as follows: interfaces are opened at appropriate positions at the bottom of the first chamber 3 and the second chamber 4, and the two interfaces are connected to the two detection ends of the differential pressure gauge 11 through pressure guide tubes; through the differential pressure gauge 11, the pressure difference between the two chambers can be monitored in real time, providing data support for pressure balance control in the static adsorption stage, while preventing the flow rate from being too fast due to excessive pressure difference in the dynamic adsorption stage, thus affecting the dynamic adsorption effect.

[0021] In some embodiments of this utility model, the adsorption component 8 is a filter element structure filled with adsorbent; More specifically, the adsorption component 8 adopts a filter element structure filled with adsorbent. The advantage is that the filter element can uniformly fix the adsorbent, preventing the adsorbent from flowing or piling up randomly, and ensuring a stable contact area between the chlorosilane and the adsorbent. At the same time, the filter element structure can form an orderly flow channel, which facilitates the full wetting of chlorosilane during static adsorption and guides the fluid to pass through uniformly during dynamic adsorption, thereby improving adsorption efficiency and consistency.

[0022] In some embodiments of this invention, the adsorbent is a macroporous adsorption resin or a molecular sieve. More specifically, macroporous adsorption resins possess a three-dimensional network structure and suitable pore size, enabling them to selectively adsorb carbon-containing organic matter through van der Waals forces and other interactions. They also exhibit good compatibility with chlorosilanes and are less prone to chemical reactions. Molecular sieves, on the other hand, possess a uniform microporous structure and strong adsorption performance. They can sieve and adsorb carbon-containing impurities based on molecular size, while also exhibiting high temperature resistance and chemical stability, maintaining stable adsorption efficiency in chlorosilane treatment environments.

[0023] In some embodiments of this utility model, the second chamber 4 has an outlet 12 on its side for the carrier gas to flow out; More specifically, after the carrier gas pushes the chlorosilane from the first chamber into the second chamber, it can be discharged in time through outlet 2 to avoid the accumulation in the second chamber, which would cause the pressure to rise and affect the flow state and dynamic adsorption effect of the chlorosilane. To achieve gas-liquid separation, preferably, an automatic exhaust valve is installed at outlet 212, which allows only the carrier gas to pass through and prevents the liquid from passing through.

[0024] In some embodiments of this invention, the hydrogen purity is ≥99.99%; More specifically, when high-purity hydrogen is used as a carrier gas, it can prevent the introduction of new pollutants due to impurities, ensuring that chlorosilanes are not secondary contaminated during dynamic adsorption and guaranteeing the purification effect.

[0025] It should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and are not intended to limit it. Although this utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solution of this utility model without departing from the spirit and scope of the technical solution of this utility model, and all such modifications or substitutions should be covered within the scope of the claims of this utility model.

Claims

1. A separation apparatus for removing carbon-containing organic matter from trichlorosilane, characterized by comprising: include: Condenser (1) is used to condense gaseous chlorosilane into liquid chlorosilane; The separator (2) is provided with a partition (5) that divides the separator (2) into a first chamber (3) and a second chamber (4), and the bottom end of the partition (5) is detached from the bottom of the separator (2); The top of the first chamber (3) is connected to an inlet 1 (6) for liquid chlorosilane to enter and an inlet 2 (7) for carrier gas to enter. The first chamber (3) from bottom to middle region and the second chamber (4) from bottom to top region are both provided with adsorption components (8); The top of the second chamber (4) is connected to an outlet (9) for the purified chlorosilane to flow out.

2. The separation apparatus for removing carbon-containing organic matter in trichlorosilane according to claim 1, wherein The first chamber (3) is connected to a level gauge (10).

3. The separation apparatus for removing carbon-containing organic matter in trichlorosilane according to claim 1, wherein The carrier gas is hydrogen.

4. The separation apparatus for removing carbon-containing organic matter in trichlorosilane according to claim 1, wherein A differential pressure gauge (11) is connected between the first chamber (3) and the second chamber (4).

5. The separation apparatus for removing carbon-containing organic matter in trichlorosilane according to claim 1, wherein The adsorption component (8) is a filter element structure filled with adsorbent.

6. The separation apparatus for removing carbon-containing organic matter in trichlorosilane according to claim 5, wherein The adsorbent is a macroporous adsorption resin or a molecular sieve.

7. The separation apparatus for removing carbon-containing organic matter in trichlorosilane according to claim 1, wherein The second chamber (4) has an outlet (12) on its side for the flow of carrier gas.

8. The separation apparatus for removing carbon-containing organic matter in trichlorosilane according to claim 3, wherein The hydrogen purity is ≥99.99%.

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