Device and method for purifying tetramethylsilane

Abstract

The invention discloses a purification device and a purification method of tetramethylsilane. A raw material tank in the purification device is used for accommodating tetramethylsilane. The light component removal rectifying tower is communicated with the raw material tank and is used for receiving tetramethylsilane and removing low-boiling-point impurities in the tetramethylsilane. The first heavy component removal rectifying tower is communicated with the light component removal rectifying tower and is used for removing high-boiling-point impurities of tetramethylsilane; the first gasifier is communicated with the first de-heavy rectifying tower and is used for gasifying tetramethylsilane; the first adsorption unit is communicated with the first gasifier and is used for adsorbing impurities of which the boiling point is close to that of tetramethylsilane; and the second de-heavy rectifying tower is communicated with the first adsorption unit and is used for receiving the tetramethylsilane adsorbed by the first adsorption unit and removing high-boiling-point impurities in the tetramethylsilane. And the second gasifier is communicated with the second de-heavy rectifying tower and is used for gasifying tetramethylsilane. And the second adsorption unit is communicated with the second gasifier and is used for adsorbing impurities with the boiling point close to that of tetramethylsilane. The purification device and the purification method are good in purification effect and low in purification cost.

Description

Technical Field

[0001] The invention belongs to the technical field of semiconductors, and in particular relates to a tetramethylsilane purification device and a purification method. Background Art

[0002] In the field of semiconductor manufacturing, ultra-high purity (mass fraction greater than 99.99%) tetramethylsilane (4MS) is a vapor deposition (including physical deposition PVD, chemical vapor deposition CVD and atomic vapor deposition ALD) precursor material, which is used to prepare silicon-based semiconductor thin film materials and is used to deposit etching barrier layers and copper diffusion barrier layers in the process of ultra-large-scale integrated circuit copper chips at 45nm and above technology nodes.

[0003] There are two main methods for preparing 4MS, one is the organic silicon conversion method, and the other is the methylchlorosilane low-boiling separation method. It is difficult to separate and purify low-boiling impurities, especially those with boiling points close to 4MS, with high energy consumption, many cycles, and complicated processes. For example, the boiling points of 4MS (299.7K) and isopentane (300.7K) are very similar; temperature control is difficult to be precise, and the separation cost is high.

[0004] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention and should not be regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art. Summary of the invention

[0005] The object of the present invention is to provide a tetramethylsilane purification device and a purification method, which have good purification effect and low purification cost.

[0006] In order to achieve the above-mentioned purpose, a specific embodiment of the present invention provides a tetramethylsilane purification device, which includes: a raw material tank, a light removal distillation tower, a first heavy removal distillation tower, a first vaporizer, a first adsorption unit, a second heavy removal distillation tower, a second vaporizer, and a second adsorption unit raw material tank, for accommodating tetramethylsilane; the light removal distillation tower is connected to the raw material tank, for receiving the tetramethylsilane and removing low-boiling impurities in the tetramethylsilane; the first heavy removal distillation tower is arranged downstream of the light removal distillation tower and is connected thereto, for removing high-boiling impurities in the tetramethylsilane; the first vaporizer is arranged in the The first de-heavy distillation tower is arranged downstream of and connected to the first de-heavy distillation tower, and is used to vaporize the tetramethylsilane; the first adsorption unit is arranged downstream of and connected to the first vaporizer, and is used to adsorb impurities with a boiling point close to that of the tetramethylsilane; the second de-heavy distillation tower is arranged downstream of and connected to the first adsorption unit, and is used to remove high-boiling point impurities in the tetramethylsilane; the second vaporizer is arranged downstream of and connected to the second de-heavy distillation tower, and is used to vaporize the tetramethylsilane; the second adsorption unit is arranged downstream of and connected to the second vaporizer, and is used to adsorb impurities with a boiling point close to that of the tetramethylsilane.

[0007] In one or more embodiments of the present invention, a reboiler is disposed at the bottom of the light removal distillation tower for reboil low boiling point impurities in the tetramethylsilane and transport the low boiling point impurities back to the light removal distillation tower.

[0008] In one or more embodiments of the present invention, a reboiler is provided at the bottom of the first weight-removing distillation tower / the second weight-removing distillation tower for reboil high-boiling-point impurities in the tetramethylsilane and transport the high-boiling-point impurities back to the first weight-removing distillation tower / the second weight-removing distillation tower.

[0009] In one or more embodiments of the present invention, a condenser is provided at the top of the light-removing distillation tower for discharging waste gas generated by the light-removing distillation tower, and tetramethylsilane mixed in the waste gas is condensed and refluxed to the light-removing distillation tower.

[0010] In one or more embodiments of the present invention, a condenser is provided at the top of the first weight-removing distillation tower / the second weight-removing distillation tower for discharging waste gas generated by the first weight-removing distillation tower / the second weight-removing distillation tower, and tetramethylsilane mixed in the waste gas is condensed and refluxed to the first weight-removing distillation tower / the second weight-removing distillation tower.

[0011] In one or more embodiments of the present invention, the first adsorption unit is filled with 13X molecular sieve; the second adsorption unit is filled with ZSM-5 molecular sieve.

[0012] Another specific embodiment of the present invention provides a method for purifying tetramethylsilane, which comprises:

[0013] The tetramethylsilane stored in the raw material tank is transported to the light removal distillation tower for light removal treatment;

[0014] The tetramethylsilane after the light removal treatment is transported to the first heavy removal distillation tower for heavy removal treatment;

[0015] The deweighted tetramethylsilane is gasified by a gasifier and transported to a first adsorption unit for adsorption treatment;

[0016] The tetramethylsilane after the adsorption treatment is transported to the second de-weighting distillation tower for de-weighting treatment;

[0017] The deweighted tetramethylsilane is gasified by a gasifier and transported to a second adsorption unit for adsorption treatment;

[0018] The adsorbed gaseous tetramethylsilane is condensed to obtain purified tetramethylsilane.

[0019] In one or more embodiments of the present invention, during the light removal treatment, the top temperature of the light removal distillation tower is between 20°C and 25°C; and / or the theoretical plate number of the light removal distillation tower is between 40 and 60; and / or the top pressure of the light removal distillation tower is between 1.4 bar and 1.5 bar; and / or the reflux feed ratio of the light removal distillation tower is between (100-30):1.

[0020] In one or more embodiments of the present invention, during the weight removal treatment, the top temperatures of the first weight removal distillation tower and the second weight removal distillation tower are between 35°C and 45°C; and / or the theoretical plate numbers of the first weight removal distillation tower and the second weight removal distillation tower are between 100 and 120; and / or the top pressures of the first weight removal distillation tower and the second weight removal distillation tower are between 1.3 bar and 1.5 bar; and / or the reflux feed ratios of the first weight removal distillation tower and the second weight removal distillation tower are between (30-10):1.

[0021] In one or more embodiments of the present invention, the mass ratio of the adsorbent filled in the first adsorption unit and the second adsorption unit is between 1:(2-4).

[0022] Compared with the prior art, the tetramethylsilane purification device of the present invention can remove low-boiling and high-boiling impurities in tetramethylsilane through a light-removing distillation tower and a heavy-removing distillation tower. The first adsorption unit and the second adsorption unit are arranged to specifically adsorb impurities such as 2-chloropropane and isopentane, which have boiling points very close to tetramethylsilane, similar polarities and are extremely difficult to separate, and can also screen out small molecule impurities such as metal salt impurities. The purification device can save raw materials and reduce the cost of purification. The purification method of tetramethylsilane can purify electronic-grade tetramethylsilane from low-boiling byproducts of methylchlorosilane, realize the efficient utilization of byproducts, and avoid the use of high-energy-consuming purification processes. At the same time, the composite use of two adsorbent materials can efficiently separate impurities close to the boiling point of tetramethylsilane, with low purification cost, low energy consumption and high economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0024] Figure 1 Schematic diagram of a tetramethylsilane purification device according to an embodiment of the present invention.

[0025] Description of main reference numerals:

[0026] 1-raw material tank, 2-light removal distillation tower, 3-first heavy removal distillation tower, 4-first vaporizer, 5-first adsorption unit, 6-second heavy removal distillation tower, 7-second vaporizer, 8-second adsorption unit, 9-reboiler, 10-condenser. DETAILED DESCRIPTION

[0027] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0028] like Figure 1As shown, a tetramethylsilane purification device in one embodiment of the present invention comprises a raw material tank 1, a light removal distillation tower 2, a first heavy removal distillation tower 3, a first vaporizer 4, a first adsorption unit 5, a second heavy removal distillation tower 6, a second vaporizer 7 and a second adsorption unit 8 which are connected in sequence. The raw material tank 1 is used to accommodate tetramethylsilane. The light removal distillation tower 2 is connected to the raw material tank 1, and is used to receive tetramethylsilane and remove low-boiling impurities therein. The first heavy removal distillation tower 3 is arranged downstream of the light removal distillation tower 2, and is connected to the light removal distillation tower 2, and is used to receive tetramethylsilane treated by the light removal distillation tower 2 and remove high-boiling impurities therein. The first vaporizer 4 is arranged downstream of the first heavy removal distillation tower 3 and is connected to the first heavy removal distillation tower 3, and is used to vaporize tetramethylsilane. The first adsorption unit 5 is arranged downstream of the first vaporizer 4 and is connected to the vaporizer, and is used to adsorb impurities with a boiling point close to that of tetramethylsilane. The second de-heavy distillation tower 6 is arranged downstream of the first adsorption unit 5 and communicated with the first adsorption unit 5, and is used to receive the tetramethylsilane adsorbed by the first adsorption unit 5 and remove high boiling point impurities therein. The second vaporizer 7 is arranged downstream of the second de-heavy distillation tower 6 and communicated with the second de-heavy distillation tower 6, and is used to vaporize tetramethylsilane. The second adsorption unit 8 is arranged downstream of the second vaporizer 7 and communicated with the second vaporizer 7, and is used to adsorb impurities with a boiling point close to that of tetramethylsilane.

[0029] The working principle of the tetramethylsilane purification device of the present invention is as follows: tetramethylsilane containing impurities is stored in a raw material tank 1. The tetramethylsilane in the raw material tank 1 can be pumped into a light removal distillation tower 2 to remove low-boiling impurities in the tetramethylsilane. The tetramethylsilane output from the light removal distillation tower 2 is sent to a first heavy removal distillation tower 3 to remove high-boiling impurities in the tetramethylsilane. The tetramethylsilane with high-boiling impurities removed is vaporized by a vaporizer and then sent to a first adsorption unit 5 to remove impurities with a boiling point close to that of tetramethylsilane. Since some impurities still exist in the tetramethylsilane after adsorption, the tetramethylsilane adsorbed by the first adsorption unit 5 can be sent to a second heavy removal distillation tower 6 to further remove residual high-boiling impurities. The tetramethylsilane treated by the second heavy removal distillation tower 6 is then vaporized by a vaporizer and sent to a second adsorption unit 8, thereby removing residual impurities with a boiling point close to that of tetramethylsilane.

[0030] The tetramethylsilane purification device of the present invention can effectively remove various impurities in tetramethylsilane by providing a light removal distillation tower 2 and two heavy removal distillation towers. The provision of two adsorption units can remove impurities in tetramethylsilane with a boiling point close to that of the tetramethylsilane, thereby simplifying the purification process and steps of tetramethylsilane and reducing production costs.

[0031] Some low-boiling impurities will remain in the tetramethylsilane after being treated by the light removal distillation tower 2. In one embodiment, a reboiler 9 is provided at the bottom of the light removal distillation tower 2. The reboiler 9 is set to a certain operating temperature, and the low-boiling impurities in the tetramethylsilane treated by the light removal distillation tower 2 can be treated by the reboiler 9 and refluxed to the light removal distillation tower 2 to fully remove the low-boiling impurities in the tetramethylsilane.

[0032] In order to remove the low-boiling impurities in the de-lightening distillation tower 2 in time, a condenser 10 is provided at the top of the de-lightening distillation tower 2, and the gaseous low-boiling impurities processed by the de-lightening distillation tower 2 are discharged through an outlet of the condenser 10. During the discharge process of the low-boiling impurities, the tetramethylsilane gas mixed with the impurities is condensed and refluxed into the de-lightening distillation tower 2. The other 20°C fraction is discharged from another outlet different from the outlet where the impurities are discharged.

[0033] Similar to the light removal distillation tower 2, a reboiler 9 is provided at the bottom of the first heavy removal distillation tower 3 to transport high-boiling impurities in tetramethylsilane back to the first heavy removal distillation tower 3 for further treatment. A reboiler 9 is provided at the bottom of the second heavy removal distillation tower 6 to transport high-boiling impurities in tetramethylsilane back to the second heavy removal distillation tower 6 for further treatment. In addition, the reboilers 9 of the first heavy removal distillation tower 3 and the second heavy removal distillation tower 6 can discharge the 50°C fraction in tetramethylsilane separately by setting the temperature.

[0034] Condensers 10 are provided at the top of the first weight-removing distillation tower 3 and the second weight-removing distillation tower 6 for discharging the impurity waste gas generated by the first weight-removing distillation tower 3 and the second weight-removing distillation tower 6 and condensing the tetramethylsilane mixed in the waste gas and refluxing it into the first weight-removing distillation tower 3 and the second weight-removing distillation tower 6.

[0035] In one embodiment, the first adsorption unit 5 is filled with 13X molecular sieve. The first adsorption unit 5 can be used to remove 2-chloropropane having a boiling point close to that of tetramethylsilane. The second adsorption unit 8 is filled with ZSM-5 molecular sieve, which is used to remove 2-chloropropane and isopentane having a boiling point close to that of tetramethylsilane. Both the first adsorption unit 5 and the second adsorption unit 8 can filter out some solid particulate impurities to obtain high-purity tetramethylsilane.

[0036] In summary, the tetramethylsilane purification device of the present invention can remove low-boiling point and high-boiling point impurities in tetramethylsilane through the light removal distillation tower 2 and the heavy removal distillation tower. The first adsorption unit 5 and the second adsorption unit 8 are arranged to specifically adsorb impurities such as 2-chloropropane and isopentane, which have boiling points very close to tetramethylsilane, similar polarities and are extremely difficult to separate, and can also screen out small molecular impurities such as metal salt impurities. The purification device can save raw materials and reduce the cost of purification.

[0037] A method for purifying tetramethylsilane in an embodiment of the present invention comprises steps S1-S5.

[0038] Step S1: transporting tetramethylsilane stored in the raw material tank 1 to the light removal distillation tower 2 for light removal treatment.

[0039] Specifically, in step S1, tetramethylsilane stored in the raw material tank 1 is transported to the de-light distillation tower 2 for de-light treatment, and some impurities are discharged through the condenser 10 at the top of the de-light distillation tower 2, and some impurities at 20°C are discharged through another outlet of the condenser 10. Among them, the top temperature of the de-light distillation tower 2 is between 20°C and 25°C to separate components with a boiling point of not less than 25°C. The theoretical plate number of the de-light distillation tower 2 is between 40 and 60. The top pressure of the de-light distillation tower 2 is between 1.4 bar and 1.5 bar. The reflux feed ratio of the de-light distillation tower 2 is (100-30):1.

[0040] Step S2: transporting the tetramethylsilane after the light removal treatment to the first heavy removal distillation tower 3 for heavy removal treatment.

[0041] Specifically, in step S2, tetramethylsilane after light removal treatment is transported to the first heavy removal distillation tower 3 for heavy removal treatment. Tetramethylsilane can remove high boiling point impurities in this step, and the high boiling point impurities can be discharged through the condenser 10 at the top of the first heavy removal distillation tower 3. Among them, the top temperature of the first heavy removal distillation tower 3 is between 35°C and 45°C. The number of theoretical plates of the first heavy removal distillation tower 3 is between 100-120. The top pressure of the first heavy removal distillation tower 3 is between 1.3bar-1.5bar. The reflux feed ratio of the first heavy removal distillation tower 3 is between (30-10):1.

[0042] Step S3: The tetramethylsilane after the deweighting treatment is gasified by the first gasifier 4 and transported to the first adsorption unit 5 for adsorption treatment.

[0043] Specifically, in step S3, the tetramethylsilane treated by the first de-heavy distillation tower 3 is transported to the first adsorption unit 5. The first adsorption unit 5 is filled with 13X molecular sieve, which can adsorb 2-chloropropane having a boiling point close to that of tetramethylsilane.

[0044] Step S4: transporting the tetramethylsilane after the adsorption treatment to the second de-weighting distillation tower 6 for de-weighting treatment.

[0045] Specifically, in step S4, the tetramethylsilane after the adsorption treatment is transported to the second de-heavy distillation tower 6. The second de-heavy distillation tower 6 can remove the high-boiling impurities remaining in the previous step, wherein the top temperature of the second de-heavy distillation tower 6 is between 35°C and 45°C. The number of theoretical plates of the second de-heavy distillation tower 6 is between 100 and 120. The top pressure of the second de-heavy distillation tower 6 is between 1.3 bar and 1.5 bar. The reflux feed of the second de-heavy distillation tower 6 is between (30-10):1.

[0046] Step S5: The tetramethylsilane after the deweighting treatment is vaporized by the second vaporizer 7 and transported to the second adsorption unit 8 for adsorption treatment.

[0047] Specifically, in step S5, the deweighted tetramethylsilane is vaporized by a vaporizer and transported to the second adsorption unit 8 for adsorption treatment. The second adsorption unit 8 is filled with ZSM-5 molecular sieves that can adsorb 2-chloropropane and isopentane, which have a boiling point close to that of tetramethylsilane. The mass ratio of the adsorbents filled in the first adsorption unit 5 and the second adsorption unit 8 is between 1:(2-4).

[0048] Step S6: Condensing the adsorbed gaseous tetramethylsilane to obtain purified tetramethylsilane.

[0049] The present invention is further described below in conjunction with specific embodiments and comparative examples.

[0050] Example 1

[0051] S1: Tetramethylsilane is subjected to light removal treatment. The top temperature of the light removal distillation tower 2 is 20°C, the reflux feed ratio is 50:1, the theoretical plate number is 40, and the top pressure is 1.4 bar.

[0052] S2: The tetramethylsilane after the light removal treatment is transported to the first heavy removal distillation tower 3 for heavy removal treatment. The top temperature of the first heavy removal distillation tower 3 is 35° C., the reflux feed ratio is 20:1, the theoretical plate number is 100, and the top pressure is 1.3 bar.

[0053] S3: The tetramethylsilane after the deweighting treatment is vaporized by the first vaporizer 4 and enters the first adsorption unit 5 for adsorption and impurity removal treatment, and the adsorbent is 13X molecular sieve.

[0054] S4: The adsorbed tetramethylsilane is placed in a second de-heavy distillation tower 6 for de-heavy treatment. The top temperature of the second de-heavy distillation tower 6 is 35° C., the reflux feed ratio is 10:1, the theoretical plate number is 100, and the top pressure is 1.3 bar.

[0055] S5: The tetramethylsilane after the secondary deweighting is vaporized in the second vaporizer 7 and enters the second adsorption unit 8 for adsorption and impurity removal treatment, and the adsorbent is ZSM-5 molecular sieve.

[0056] Among them, the filling mass ratio of 13X molecular sieve and ZSM-5 molecular sieve is 1:4.

[0057] The above method was used to treat three groups of the same tetramethylsilane. The components in the tetramethylsilane raw material are shown in Table 1 below.

[0058] Table 1 Raw material composition information

[0059] Raw material components Boiling point(℃) content(%) Isobutylene -6.9 0.05 Cis-2-Butene 3.7 0.77 trans-2-butene 1 0.03 4MS 28 48.86 Isopentane 30 10.29 2-Chloropropane 35 4.66 Cyclopropylethane 37 0.11 2-Methyl-2-butene 35 2.88 Pentene 30 1.65 2-Pentene 37 25.66 2-Methyl-2-chloro-propane 51 0.49 Tetramethyldihydrogendisiloxane 70 3.47 2-Methyl-2-chloro-butane 85 0.26 Hexamethyldihydrogentrisiloxane 128 0.8

[0060] The components of the three groups of tetramethylsilane after being treated by the above method are shown in Table 2 below.

[0061] Table 2 Component information of tetramethylsilane after distillation and adsorption

[0062] Components after distillation and adsorption (%) Group 1 Group 2 Group 3 Tetramethylsilane 99.996 99.995 99.998 Isopentane <0.0001 <0.0001 <0.0001 2-Chloropropane <0.0001 <0.0001 <0.0001 other <0.001 <0.001 <0.001

[0063] Comparative Example 1

[0064] S1: Tetramethylsilane is subjected to light removal treatment, the top temperature of the light removal distillation tower is 20°C, the reflux feed ratio is 100:1, the theoretical plate number is 40, and the top pressure is 1.4 bar.

[0065] S2: The tetramethylsilane after light removal treatment is transported to a heavy removal distillation tower for heavy removal treatment. The top temperature of the heavy removal distillation tower is 35°C, the reflux feed ratio is 20:1, the theoretical plate number is 100, and the top pressure is 1.3 bar.

[0066] S3: The deweighted tetramethylsilane is placed in an adsorption unit for adsorption and impurity removal, and the adsorbent is 13X molecular sieve.

[0067] Comparative Example 2

[0068] S1: Tetramethylsilane is subjected to light removal treatment, the top temperature of the light removal distillation tower is 20°C, the reflux feed ratio is 100:1, the theoretical plate number is 40, and the top pressure is 1.4 bar.

[0069] S2: The adsorbed tetramethylsilane is placed in a de-heavy distillation tower for de-heavy treatment. The top temperature of the de-heavy distillation tower is 35°C, the reflux feed ratio is 20:1, the theoretical plate number is 100, and the top pressure is 1.3 bar.

[0070] S3: The deweighted tetramethylsilane is placed in an adsorption unit for adsorption and impurity removal, and the adsorbent is ZSM-5 molecular sieve.

[0071] The above two methods were used to treat tetramethylsilane, and the treatment results are shown in Table 3 below.

[0072] Table 3 Tetramethylsilane component information after adsorption on a single adsorbent

[0073] Components after single molecular sieve purification (%) Comparative Example 1 Comparative Example 2 Tetramethylsilane 90.12 99.995 Isopentane 10.35 <0.0001 2-Chloropropane <0.0001 <0.0001 other 0.53 <0.001

[0074] Under the same distillation and purification conditions as Example 1, the adsorbent filling type was changed, and only one molecular sieve was filled in the adsorption column. Only 13X was filled in Comparative Example 1, and only ZSM-5 was filled in Comparative Example 2. As shown in Table 3, 13X has an obvious adsorption effect on 2-chloropropane impurities, and ZSM-5 has an adsorption effect on both isopentane and 2-chloropropane, but compared with the presence of the two adsorbents at the same time, the purity of tetramethylsilane purified by adsorption of only 13X single molecular sieve is lower than the expected target; only ZSM-5 adsorption purification can obtain high-purity tetramethylsilane, but its adsorption amount of isopentane is reduced, so that a larger amount of molecular sieves are required, resulting in increased costs.

[0075] In summary, the method for purifying tetramethylsilane of the present invention can purify electronic grade tetramethylsilane from low-boiling byproducts of methylchlorosilane, realize the efficient utilization of byproducts, and avoid the use of high energy consumption purification process. At the same time, the composite use of two adsorbent materials can efficiently separate impurities with a boiling point close to that of tetramethylsilane, with low purification cost, low energy consumption, and high economic benefit.

[0076] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0077] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A tetramethylsilane purification device, characterized in that, include: A raw material tank, used for containing tetramethylsilane; a light removal distillation tower, connected to the raw material tank, for receiving the tetramethylsilane and removing low boiling point impurities in the tetramethylsilane; A first heavy removal distillation tower, disposed downstream of the light removal distillation tower and connected thereto, for removing high boiling point impurities in the tetramethylsilane; a first vaporizer, disposed downstream of the first de-weighting distillation tower and in communication therewith, and configured to vaporize the tetramethylsilane; a first adsorption unit, disposed downstream of the first vaporizer and in communication with the first vaporizer, for adsorbing impurities having a boiling point close to that of the tetramethylsilane; a second de-weighting distillation tower, disposed downstream of the first adsorption unit and in communication therewith, for removing high-boiling-point impurities in the tetramethylsilane; a second vaporizer, disposed downstream of the second de-weighting distillation tower and in communication therewith, for vaporizing the tetramethylsilane; and The second adsorption unit is arranged downstream of the second vaporizer and communicated with the second vaporizer, and is used for adsorbing impurities with a boiling point close to that of the tetramethylsilane.

2. The tetramethylsilane purification device according to claim 1, characterized in that: A reboiler is disposed at the bottom of the light removal distillation tower for reboiling low-boiling impurities in the tetramethylsilane and conveying the low-boiling impurities back to the light removal distillation tower.

3. The tetramethylsilane purification device according to claim 1, characterized in that: A reboiler is provided at the bottom of the first weight-removing distillation tower / the second weight-removing distillation tower for reboiling high-boiling-point impurities in the tetramethylsilane and transporting the high-boiling-point impurities back to the first weight-removing distillation tower / the second weight-removing distillation tower.

4. The tetramethylsilane purification device according to claim 1, characterized in that: A condenser is provided at the top of the light removal distillation tower for discharging waste gas generated by the light removal distillation tower, and tetramethylsilane mixed in the waste gas is condensed and refluxed to the light removal distillation tower.

5. The tetramethylsilane purification device according to claim 1, characterized in that: A condenser is provided at the top of the first weight-removing distillation tower / the second weight-removing distillation tower for discharging waste gas generated by the first weight-removing distillation tower / the second weight-removing distillation tower, and tetramethylsilane mixed in the waste gas is condensed and refluxed to the first weight-removing distillation tower / the second weight-removing distillation tower.

6. The tetramethylsilane purification device according to claim 1, characterized in that: The first adsorption unit is filled with 13X molecular sieve; the second adsorption unit is filled with ZSM-5 molecular sieve.

7. A method for purifying tetramethylsilane, characterized in that: include: The tetramethylsilane stored in the raw material tank is transported to the light removal distillation tower for light removal treatment; The tetramethylsilane after the light removal treatment is transported to the first heavy removal distillation tower for heavy removal treatment; The deweighted tetramethylsilane is gasified by a first gasifier and transported to a first adsorption unit for adsorption treatment; The tetramethylsilane after the adsorption treatment is transported to the second de-weighting distillation tower for de-weighting treatment; The deweighted tetramethylsilane is gasified by a second gasifier and transported to a second adsorption unit for adsorption treatment; The adsorbed gaseous tetramethylsilane is condensed to obtain purified tetramethylsilane.

8. The method for purifying tetramethylsilane according to claim 7, characterized in that: During the light removal treatment, the top temperature of the light removal distillation tower is between 20°C and 25°C; and / or the theoretical plate number of the light removal distillation tower is between 40 and 60; and / or the top pressure of the light removal distillation tower is between 1.4 bar and 1.5 bar; and / or the reflux feed ratio of the light removal distillation tower is between (100-30):

1.

9. The method for purifying tetramethylsilane according to claim 7, characterized in that: During the weight removal treatment, the top temperature of the first weight removal distillation tower and the second weight removal distillation tower is between 35°C and 45°C; and / or, the theoretical plate numbers of the first weight removal distillation tower and the second weight removal distillation tower are between 100 and 120; and / or, the top pressures of the first weight removal distillation tower and the second weight removal distillation tower are between 1.3 bar and 1.5 bar; and / or, the reflux feed ratio of the first weight removal distillation tower and the second weight removal distillation tower is between (30-10):

1.

10. The method for purifying tetramethylsilane according to claim 7, characterized in that: The mass ratio of the adsorbent filled in the first adsorption unit and the second adsorption unit is between 1:(2-4).

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