A device for detecting silicon content in metallic silicon

Abstract

This invention discloses a device for detecting silicon content in metallic silicon, comprising a container (1), which is connected to a reaction apparatus (3) via a gas collecting bottle (2). The reaction apparatus (3) includes a constant-pressure funnel (31) for storing sodium hydroxide solution. The top of the constant-pressure funnel (31) is connected to the gas collecting bottle (2), and the bottom of the constant-pressure funnel (31) is connected to a flask (32) for storing metallic silicon powder. A heating magnetic stirrer (4) is provided below the flask (32), and a water bath (8) is provided at the top of the heating magnetic stirrer (4). The flask (32) is located in the water bath (8). The bottom of the constant-pressure funnel (31) is provided with an outlet pipe (310), and the top of the flask (32) is provided with an inlet pipe (320). The inlet pipe (320) is connected to the outlet pipe (310) via a flexible hose (33). This invention has the advantages of a short detection cycle and high operational safety.

Description

Technical Field

[0001] This utility model relates to the field of metal silicon composition analysis technology, and in particular to a device for detecting silicon content in metal silicon. Background Technology

[0002] Currently, the detection of silicon content in metallic silicon mainly relies on the gravimetric method. The core principle is to convert the silicon in the sample into a sparingly soluble silicon compound through chemical treatment. After filtration, washing, and ignition, the mass is weighed, and the silicon content is calculated based on the stoichiometric relationship between silicon dioxide and silicon. The chemical treatment uses volatile hydrofluoric acid, which is highly hazardous. Ignition requires a muffle furnace, which involves numerous precautions, is cumbersome and time-consuming, and results in a long detection cycle. Utility Model Content

[0003] The purpose of this invention is to provide a device for detecting the silicon content in metallic silicon. This invention has the advantages of a short detection cycle and high operational safety.

[0004] The technical solution of this utility model is as follows: A device for detecting silicon content in metallic silicon includes a container, which is connected to a reaction device via a gas collecting bottle. The reaction device includes a constant pressure funnel for storing sodium hydroxide solution. The top of the constant pressure funnel is connected to the gas collecting bottle, and the bottom of the constant pressure funnel is connected to a flask for storing metallic silicon powder. A heating magnetic stirrer is provided below the flask, and a water bath is provided on the top of the heating magnetic stirrer. The flask is located in the water bath.

[0005] In the aforementioned device for detecting silicon content in metallic silicon, the bottom of the constant pressure funnel is provided with an outlet pipe, the top of the flask is provided with an inlet pipe, and the inlet pipe is connected to the outlet pipe through a flexible tube.

[0006] In the aforementioned device for detecting silicon content in metallic silicon, the device further includes a support, a constant pressure funnel fixed to the support, and a flask connected to the support via a swing mechanism that causes the flask to swing.

[0007] In the aforementioned device for detecting silicon content in metallic silicon, the swing mechanism includes a gripper for holding the flask, the gripper being rotatably connected to the support via a mounting rod, and the mounting rod being provided with a rotating pivot plate.

[0008] In the aforementioned device for detecting silicon content in metallic silicon, a soft-seal structure is provided at the connection between the hose and the inlet pipe and at the connection between the hose and the outlet pipe.

[0009] In the aforementioned device for detecting silicon content in metallic silicon, the soft sealing structure is a petrolatum coating.

[0010] In the aforementioned device for detecting silicon content in metallic silicon, a stir bar is placed inside the flask, and the surface of the stir bar is covered with an anti-corrosion layer.

[0011] In the aforementioned device for detecting silicon content in metallic silicon, the anti-corrosion layer is a polytetrafluoroethylene coating.

[0012] In the aforementioned device for detecting silicon content in metallic silicon, the container is connected to a gas collecting bottle via a first conduit, and the gas collecting bottle is connected to a constant pressure funnel via a second conduit.

[0013] The aforementioned device for detecting silicon content in metallic silicon also includes an environmental parameter calibration device, which comprises a pressure detector and a temperature detector.

[0014] Compared with existing technologies, this invention utilizes a flask to store metallic silicon powder and a constant-pressure funnel to store a sodium hydroxide solution that reacts with the metallic silicon powder. The sodium hydroxide solution is released into the metallic silicon powder, and a heated magnetic stirrer is used to heat and stir the mixture, allowing the metallic silicon powder to fully react and produce hydrogen gas. The hydrogen gas enters a gas collecting bottle, from which a pre-stored liquid is discharged. The volume of hydrogen gas produced can be determined from the volume of the discharged liquid. Based on the mass of the metallic silicon powder and the volume of hydrogen gas produced, the silicon content in the metallic silicon can be calculated. The procedure is simple, the detection cycle is short, and no volatile reagents are used, resulting in high operational safety. This invention has the advantages of a short detection cycle and high operational safety. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of Example 1.

[0016] Figure 2 This is a schematic diagram of the reaction apparatus in Example 2.

[0017] Figure 3 This is a schematic diagram of the swing mechanism.

[0018] Figure 4 This is a schematic diagram of the connection between the constant pressure funnel and the flask. Detailed Implementation

[0019] The present invention will be further described below with reference to the accompanying drawings and embodiments, but this should not be construed as limiting the present invention.

[0020] Example 1: A device for detecting silicon content in metallic silicon, such as... Figure 1 As shown, from left to right, the container 1, gas collecting bottle 2, and reaction apparatus 3 are arranged sequentially. Reaction apparatus 3 includes a constant-pressure funnel 31 and a flask 32. Container 1 is connected to gas collecting bottle 2 via a first conduit 6. Gas collecting bottle 2 is connected to the top inlet of constant-pressure funnel 31 via a second conduit 7. The bottom outlet of constant-pressure funnel 31 is connected to the top inlet of flask 32. Container 1 is a beaker, and flask 32 is a ground glass flask for better sealing.

[0021] A heated magnetic stirrer 4 is located at the bottom of flask 32, with stirring parameters of 300-500 rpm. A water bath 8 is located on top of the heated magnetic stirrer 4, and the lower part of flask 32 is immersed in the water bath 8. Flask 32 uses a 24 / 29 standard grinding interface.

[0022] A stir bar is placed inside the flask 32. The surface of the stir bar is covered with an anti-corrosion layer, which is a polytetrafluoroethylene coating.

[0023] The detection device also includes an environmental parameter calibration device, which comprises a barometer and a temperature detector.

[0024] Example 2: Further optimization based on Example 1, such as... Figures 2 to 4 As shown, the bottom of the constant pressure funnel 31 is provided with an outlet pipe 310, and the top of the flask 32 is provided with an inlet pipe 320. The inlet pipe 320 is connected to the outlet pipe 310 through a hose 33.

[0025] The constant pressure funnel 31 is fixed to the support 9, and the flask 32 is connected to the support 9 through the swing mechanism 5. The swing mechanism 5 causes the flask 32 to swing (shake), and the swing angle is 5-30°.

[0026] The swing mechanism 5 includes a gripper 51 (equivalent to a clamp) for holding the flask 32. The gripper 51 is rotatably connected to the bracket 9 via a mounting rod 52. One end of the mounting rod 52 passes through the bracket 9 and is provided with a rotating pivot disk 53 (equivalent to an operating disk).

[0027] The connection between the hose 33 and the inlet pipe 320, as well as the connection between the hose 33 and the outlet pipe 310, are provided with soft sealing structures. The soft sealing structures are coated with petroleum jelly. By setting the soft sealing structures, the airtightness leakage rate is ensured to be <0.1mL / min.

[0028] In Example 2, by setting up a swing mechanism 5, the flask 32 is gently shaken during the reaction process, ensuring that the solution completely submerges the powder, resulting in a more thorough mixing reaction. Simultaneously, the solution drips onto the tilted wall of the flask 32 upon entry, and the rinsing bubbles carry away any powder adhering to the wall, thus preventing powder from sticking to the flask 32 and causing incomplete reaction. This structure offers controllable and stable swing angles and is easy to operate. Specifically, after the reaction apparatus 3 is assembled, during the reaction, the mounting rod 52 can be manually rotated via the rotating pivot plate 53, and the swing of the mounting rod 52 causes the flask 32 to swing synchronously.

[0029] Example 3: A method for detecting silicon content in metallic silicon, comprising the following steps:

[0030] S1. Weigh 20g of sample silicon metal particles, grind them into fine powder of 40-200 mesh, dry them in a drying oven, take 0.2002g and record it as m0, and add it to flask 32.

[0031] S2. Build the detection device of Example 1 or Example 2 and verify its airtightness.

[0032] S3. Fill gas collecting bottle 2 with clean water and seal the opening of gas collecting bottle 2 with a rubber stopper to maintain a seal.

[0033] S4. The first conduit 6 of the gas collecting bottle 2 is placed in a plastic container to collect the clean water discharged from the gas collecting bottle 2.

[0034] S5. Open the rubber stopper on the constant pressure funnel 31, add 30 mL of the pre-prepared 20% wt. NaOH solution to the constant pressure funnel 31, and then tighten the rubber stopper to keep it sealed.

[0035] S6. Open the valve of the constant pressure funnel 31 to allow the NaOH solution to flow into the flask 32. Close the valve and gently shake the flask 32 to completely submerge the powder.

[0036] S7. Use a heated magnetic stirrer 4 to heat flask 32 in a constant temperature water bath at 70℃±1℃ for 60 minutes, while simultaneously performing magnetic stirring.

[0037] After 60 minutes, flask 32 is placed in a cold water bath at 15℃±0.5℃. After about 15 minutes, the gas inside the apparatus can be restored to room temperature.

[0038] S9. Remove the first tube 6 from container 1 and measure the volume of water discharged throughout the process with a graduated cylinder. This volume is the volume of hydrogen gas generated in the reaction, 330 ml, denoted as V1.

[0039] S10. Calculate the silicon content: Si content = (28.09*V1*P) / (2*8.314*T*m0)×100%, where P is the real-time air pressure (kPa), T is the thermodynamic temperature (K), and m0 is the sample mass.

[0040] Preferably, the grinding process includes particle size classification and sieving, requiring ≥95% of particles to be 40-200 mesh. Particles that do not meet the standard are returned for secondary grinding. Due to the hygroscopic nature of silica powder, it must be ground, dried, and then sealed for storage. In Example 3, hazardous reagents such as hydrofluoric acid and nitric acid are avoided; the entire process requires only NaOH solution and water, meeting green testing standards. A dynamic calibration formula for air pressure and temperature (V0=nRT / P) is introduced, using real-time acquisition of environmental parameters (air pressure, room temperature) to correct the hydrogen molar volume, improving the calculation accuracy to ±0.5%.

[0041] It should be noted that the detection device in Example 3 is suitable for rapid quality inspection in industrial settings, requiring metallic silicon products with a silicon content of 85%-99.9% and a repeatability RSD ≤ 0.8%. It utilizes innovative gas preparation and volume measurement technologies to promote green technology upgrades, reduce reagent usage, lower environmental risks, and combine high efficiency with safety.

[0042] In the description of this utility model, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

Claims

1. A device for detecting silicon content in metallic silicon, characterized in that: The apparatus includes a container (1), which is connected to a reaction device (3) via a gas collecting bottle (2). The reaction device (3) includes a constant pressure funnel (31) for storing sodium hydroxide solution. The top of the constant pressure funnel (31) is connected to the gas collecting bottle (2), and the bottom of the constant pressure funnel (31) is connected to a flask (32) for storing silicon metal powder. A heating magnetic stirrer (4) is provided below the flask (32), and a water bath (8) is provided on the top of the heating magnetic stirrer (4). The flask (32) is located in the water bath (8).

2. The metal silicon silicon content detection device according to claim 1, characterized in that: The constant pressure funnel (31) is provided with an outlet pipe (310) at the bottom and an inlet pipe (320) at the top of the flask (32). The inlet pipe (320) is connected to the outlet pipe (310) through a hose (33).

3. The metal silicon silicon content detection device according to claim 2, characterized in that: The detection device also includes a support (9), a constant pressure funnel (31) fixed to the support (9), and a flask (32) connected to the support (9) through a swing mechanism (5). The swing mechanism (5) causes the flask (32) to swing.

4. The device for detecting silicon content in metallic silicon according to claim 3, characterized in that: The swing mechanism (5) includes a gripper (51) for holding the flask (32), the gripper (51) is rotatably connected to the bracket (9) via a mounting rod (52), and the mounting rod (52) is provided with a rotating pivot plate (53).

5. The metal silicon silicon content detection device according to claim 2, characterized in that: The connection between the hose (33) and the inlet pipe (320) and the connection between the hose (33) and the outlet pipe (310) are both provided with soft sealing structures.

6. The metal silicon silicon content detection device according to claim 5, characterized in that: The soft sealing structure is a petroleum jelly coating.

7. The metal silicon silicon content detection device according to claim 1, characterized in that: A stir bar is placed inside the flask (32), and the surface of the stir bar is covered with an anti-corrosion layer.

8. The metal silicon silicon content detection device according to claim 7, characterized in that: The anti-corrosion layer is a polytetrafluoroethylene coating.

9. The metal silicon silicon content detection device according to claim 1, characterized in that: The container (1) is connected to the gas collecting bottle (2) through the first conduit (6), and the gas collecting bottle (2) is connected to the constant pressure funnel (31) through the second conduit (7).

10. The metal silicon silicon content detection device according to claim 7, characterized in that: The detection device also includes an environmental parameter calibration device, which comprises a barometer and a temperature detector.

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