Closed sample preparation device for impurity analysis of chlorosilane

Abstract

The utility model discloses a closed sample preparation device for chlorosilane impurity analysis. The closed sample preparation device comprises a furnace body, a porous heating plate, a digestion tank and a nitrogen pipeline, the porous heating plate is arranged inside the furnace body, and a group of fixing holes for placing the digestion tank are reserved in the plate surface; one end of the nitrogen pipeline is connected to an external nitrogen source through a nitrogen inlet pipe, and the other end of the nitrogen pipeline is respectively connected to the corresponding digestion tanks through a group of shunt pipes; the digestion tank is provided with a gas inlet used for being connected with a nitrogen pipeline and a material inlet used for a sample. According to the device, system errors caused by sample pollution can be effectively avoided and reduced, a nitrogen auxiliary device is matched for purging in the heating and concentrating process, the sample is prevented from directly contacting with air to react, and the safety is improved.

Description

Technical Field

[0001] The utility model belongs to the field of polysilicon production, and particularly relates to a closed sample preparation device for chlorosilane impurity analysis. Background Art

[0002] In polysilicon production, chlorosilane is a key raw material. By testing and analyzing the impurity content in chlorosilane, the entire production process is monitored to ensure continuous and stable operation, thereby achieving control over product quality. The impurity content in chlorosilane is a major factor affecting the quality of polysilicon products.

[0003] The analysis of impurity elements in chlorosilanes is a trace analysis requiring demanding technical expertise. Furthermore, the sample collection and preparation process are susceptible to contamination. Therefore, reducing or avoiding contamination during sample preparation and optimizing the enrichment of boron, phosphorus, and other metal elements has become a major research challenge.

[0004] Chlorosilane is a chemical that reacts violently with compounds containing active hydrogen and evaporates rapidly in the air. According to literature research, there are a variety of pretreatment methods for chlorosilane samples, with hydrolysis and concentration methods currently being the most commonly used. The hydrolysis method involves first hydrolyzing the chlorosilane, adding acid to dissolve the hydrolyzate, and converting the boron and phosphorus in the sample into boric acid or phosphoric acid. After digestion, the boron and phosphorus content is detected. During sample pretreatment, boron and phosphorus easily evaporate with the chlorosilane, resulting in inaccurate test results and poor test stability. The concentration method involves adding a chelating agent to the sample solution to form a stable complex with the metal ions. However, if a polytetrafluoroethylene tongs is used in an open state during sample processing, the sample is easily contaminated, resulting in poor test results and reproducibility. Summary of the Invention

[0005] Purpose of the utility model: The technical problem to be solved by the utility model is to provide a closed sample preparation device to reduce the risk of contamination of samples to be analyzed in response to the shortcomings of the existing technology.

[0006] In order to achieve the above purpose, the technical solution adopted by the utility model is as follows:

[0007] A closed sample preparation device for chlorosilane impurity analysis comprises a furnace body, a porous heating plate, a digestion tank, and a nitrogen pipeline; the porous heating plate is arranged inside the furnace body, and a group of fixing holes for placing the digestion tank are reserved on the plate surface; one end of the nitrogen pipeline is connected to an external nitrogen gas source through a nitrogen inlet pipe, and the other end is connected to the corresponding digestion tank through a group of manifolds; the digestion tank is provided with an air inlet for connecting to the nitrogen pipeline and a feed port for the sample.

[0008] Furthermore, a temperature sensor is installed on the porous heating plate through a thread, and the temperature sensor is connected to a control panel outside the furnace body for displaying the temperature inside the furnace body.

[0009] Furthermore, a pressure reducing valve and a nitrogen flow meter are installed on the nitrogen pipeline. The nitrogen flow meter is connected to a control panel outside the furnace body and is used to monitor the real-time flow of nitrogen in the nitrogen pipeline.

[0010] Furthermore, the control panel is also provided with a power indicator light, a power switch and a temperature control display screen.

[0011] Furthermore, the furnace body is formed by CNC precision processing of aluminum plates and is entirely coated with a high-temperature resistant PVDF coating.

[0012] Furthermore, a furnace door that can be opened and closed is provided on one side of the furnace body, and the furnace door is connected to the furnace body through a hinge.

[0013] Furthermore, the digestion tank is made of PFA material.

[0014] Furthermore, a group of PTFE footings are provided at the bottom of the furnace body.

[0015] Furthermore, the porous heating plate is provided with 3×6 fixed holes, a total of 18 holes, corresponding to the placement of 18 digestion tanks.

[0016] Furthermore, the nitrogen pipeline, nitrogen inlet pipe and diversion pipe are all made of PU material.

[0017] When in use, install a pressure reducing valve on the front end of the nitrogen inlet pipe and insert it into the nitrogen flow meter inlet port. Then screw the temperature sensor thread head into the internal thread on the heating plate to connect the heating plate and the temperature control display. Place the digestion tank on the heating plate.

[0018] Use PU tubing to connect the digestion tank to the nitrogen diversion hole on the furnace body. Purge the sample during the chlorosilane treatment process to prevent direct contact between the sample and air. To use it, adjust the nitrogen flow meter, turn on the power switch, and adjust the temperature of the hot plate. Place the digestion tank with two holes on the hot plate. One hole is connected to the nitrogen diversion hole in the furnace body with PU tubing, and the other hole is used to add the sample and the acid used for digestion. Nitrogen is continuously purged during the heating and concentration process to prevent direct contact between the sample and air, thereby achieving the purpose of closed sample preparation. Beneficial effects

[0019] This device effectively avoids and reduces systematic errors caused by sample contamination. A nitrogen-assisted purge system, combined with a nitrogen-assisted device, provides a safer, more efficient method for purging samples during the heating and concentration process, preventing direct contact and reaction with air. This reduces the risk of introducing other impurities during chlorosilane sample preparation, which could lead to sample contamination and systematic errors. Adjusting the heating plate temperature and nitrogen purge flow rate as needed effectively prevents spontaneous combustion of chlorosilane during heating, under the protection of nitrogen, and prevents fire hazards. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, and the above and / or other advantages of the present invention will become more apparent.

[0021] Figure 1 It is a schematic diagram of the overall structure of the closed sample preparation device.

[0022] Figure 2 It is a schematic diagram of the internal and external structures of the closed sample preparation device.

[0023] Figure 3 It is a top view schematic diagram of the internal and external structures of the closed sample preparation device.

[0024] Wherein, each reference numeral represents:

[0025] 1-Power indicator light; 2-Power switch; 3-Temperature control display; 4-Digestion tank; 5-Porous heating plate; 6-Temperature sensor; 7-Nitrogen flowmeter; 8-Furnace body; 9-Nitrogen pipeline; 10-Fixing hole; 11-Air inlet; 12-Feed port; 13-Control panel; 14-Furnace door; 15-Foot anchor; 16-Nitrogen inlet pipe. DETAILED DESCRIPTION

[0026] The present invention can be better understood according to the following embodiments.

[0027] The structures, proportions, sizes, etc. illustrated in the drawings of the specification are only used to match the contents disclosed in the specification for the understanding and reading of those familiar with this technology. They are not used to limit the conditions for the implementation of the utility model and therefore have no substantial technical significance. Any modification of the structure, change in the proportional relationship, or adjustment of the size should still fall within the scope of the technical content disclosed in the utility model without affecting the efficacy and purpose of the utility model. At the same time, terms such as "upper", "lower", "front", "back", and "middle" quoted in this specification are only for the convenience of description and are not used to limit the scope of the implementation of the utility model. Changes or adjustments in their relative relationships should also be considered as the scope of the implementation of the utility model without substantially changing the technical content.

[0028] Combine Figures 1 to 3 The utility model provides a closed sample preparation device for chlorosilane impurity analysis, comprising a furnace body 8, a porous heating plate 5, a digestion tank 4 and a nitrogen pipeline 9; the porous heating plate 5 is arranged inside the furnace body 8, and a group of fixing holes 10 for placing the digestion tank 4 is reserved on the plate surface; one end of the nitrogen pipeline 9 is connected to an external nitrogen gas source through a nitrogen inlet pipe 16, and the other end is connected to the corresponding digestion tank 4 through a group of diversion pipes; the digestion tank 4 is provided with an air inlet 11 for connecting to the nitrogen pipeline 9 and a feed port 12 for the sample.

[0029] In some embodiments, a temperature sensor 6 is threadedly mounted on the porous heating plate 5 , and the temperature sensor 6 is connected to a control panel 13 outside the furnace body 8 for displaying the internal temperature of the furnace body 8 .

[0030] In some embodiments, a pressure reducing valve and a nitrogen flow meter 7 are installed on the nitrogen pipeline 9 . The nitrogen flow meter 7 is connected to a control panel 13 outside the furnace body 8 to monitor the real-time flow of nitrogen in the nitrogen pipeline 9 .

[0031] In some embodiments, the control panel 13 is further provided with a power indicator light 1 , a power switch 2 and a temperature control display screen 3 .

[0032] In this embodiment, the furnace body 8 is formed by CNC precision processing of aluminum plate, and is entirely coated with a high-temperature resistant PVDF coating.

[0033] In this embodiment, a furnace door 14 that can be opened and closed is provided on one side of the furnace body 8, and the furnace door 14 is connected to the furnace body 8 through a hinge.

[0034] In this embodiment, the digestion tank 4 is made of PFA material.

[0035] In this embodiment, a group of PTFE footings 15 are provided at the bottom of the furnace body 8 .

[0036] In this embodiment, the porous heating plate 5 is provided with 3×6 fixing holes 10 , a total of 18 holes, corresponding to the placement of 18 digestion tanks 4 .

[0037] In this embodiment, the nitrogen pipeline 9, the nitrogen inlet pipe 16 and the diversion pipe are all made of PU material.

[0038] The specific process of using this device for closed sample preparation of chlorosilane is as follows:

[0039] (1) Screw the threaded head of the temperature sensor 6 into the internal thread of the porous heating plate 5.

[0040] (2) Insert the nitrogen inlet pipe 16 into the nitrogen flow meter 7 inlet port (8*5PU pipe), and a pressure reducing valve needs to be installed at the front end.

[0041] (3) Connect the heating wires to the porcelain joints according to the markings on them. L to L, N to N.

[0042] (4) Insert the power plug into the socket, (10A).

[0043] (5) Turn the heating switch to the right, the power indicator light 1 will light up, and the device will enter the heating state.

[0044] (6) According to the required heating temperature, press the up and down arrows on the temperature controller to set the temperature. Green indicates the set temperature and white indicates the measured temperature.

[0045] (7) The temperature setting range is 60~180℃, and the temperature is displayed in real time using the temperature control display 3.

[0046] (8) Wipe the inner wall of the PFA digestion tank 4 with a wet dust-free cloth for at least 3 times, clean the digestion tank and cup cover more than 20 times under flowing ultrapure water, and blow dry with nitrogen.

[0047] (9) Place the PFA digestion tank 4 in the fixed hole 10 of the porous heating plate 5 and mark it. Connect one hole of the digestion tank 4 to the nitrogen assist device, and leave the other hole open. Use a pipette to add a few milliliters (1 mL) of acetonitrile to the hole, then add a few milliliters (10 mL) of sample, and evaporate to dryness (100°C).

[0048] (10) Turn off the nitrogen, add a few milliliters (0.1 mL) of 1% mannitol solution and a few milliliters (1 mL) of hydrofluoric acid to the PFA digestion tank 4 where the sample has been evaporated, adjust the temperature to (120°C) and continue heating to evaporate.

[0049] (11) Remove the PFA digestion tank 4 from the sealed sample preparation device and cool it to room temperature. Add a few milliliters (5 mL) of 3% nitric acid solution and mix well. Place the sample to be tested into the sample box and transfer it to the ICP-OES for detection.

[0050] (12) Analyze, calculate and export the data, clean the operating table, clean the digestion tank 4, and soak the cleaned digestion tank 4 in 5% nitric acid solution.

[0051] This utility model provides a concept and method for a sealed sample preparation device for chlorosilane impurity analysis. There are many methods and approaches to implement this technical solution. The above is only a preferred embodiment of the utility model. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the utility model, and such improvements and modifications should also be considered within the scope of protection of the utility model. Any components not specified in this embodiment may be implemented using existing technologies.

Claims

1. A closed sample preparation device for chlorosilane impurity analysis, characterized in that: The invention comprises a furnace body (8), a porous heating plate (5), a digestion tank (4) and a nitrogen pipeline (9); the porous heating plate (5) is arranged inside the furnace body (8), and a group of fixing holes (10) for placing the digestion tank (4) are reserved on the plate surface; one end of the nitrogen pipeline (9) is connected to an external nitrogen gas source through a nitrogen inlet pipe (16), and the other end is connected to the corresponding digestion tank (4) through a group of diversion pipes; the digestion tank (4) is provided with an air inlet (11) for connecting to the nitrogen pipeline (9) and a feed port (12) for samples.

2. The closed sample preparation device for chlorosilane impurity analysis according to claim 1, characterized in that: A temperature sensor (6) is threadedly mounted on the porous heating plate (5), and the temperature sensor (6) is connected to a control panel (13) outside the furnace body (8) for displaying the internal temperature of the furnace body (8).

3. The closed sample preparation device for chlorosilane impurity analysis according to claim 1, characterized in that: A pressure reducing valve and a nitrogen flow meter (7) are installed on the nitrogen pipeline (9). The nitrogen flow meter (7) is connected to a control panel (13) outside the furnace body (8) and is used to monitor the real-time flow of nitrogen in the nitrogen pipeline (9).

4. The closed sample preparation device for chlorosilane impurity analysis according to claim 2 or 3, characterized in that: The control panel (13) is also provided with a power indicator light (1), a power switch (2) and a temperature control display screen (3).

5. The closed sample preparation device for chlorosilane impurity analysis according to claim 1, characterized in that: The furnace body (8) is formed by CNC precision processing of aluminum plates, and the entire body is coated with a high-temperature resistant PVDF coating.

6. The closed sample preparation device for chlorosilane impurity analysis according to claim 1, characterized in that: A furnace door (14) that can be opened and closed is provided on one side of the furnace body (8), and the furnace door (14) is connected to the furnace body (8) via a hinge.

7. The closed sample preparation device for chlorosilane impurity analysis according to claim 1, characterized in that: The digestion tank (4) is made of PFA material.

8. The closed sample preparation device for chlorosilane impurity analysis according to claim 1, characterized in that: A group of PTFE footings (15) are provided at the bottom of the furnace body (8).

9. The closed sample preparation device for chlorosilane impurity analysis according to claim 1, characterized in that: The porous heating plate (5) is provided with 3×6 fixing holes (10), a total of 18, corresponding to the placement of 18 digestion tanks (4).

10. The closed sample preparation device for chlorosilane impurity analysis according to claim 1, characterized in that: The nitrogen pipeline (9), nitrogen inlet pipe (16) and diversion pipe are all made of PU material.

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