A purification method, device and application for efficiently obtaining silane and disilane

Abstract

The present invention relates to a purification method, device and application for efficiently obtaining silane and disilane. The method adopts a single-stage multi-layer adsorption combined with a first-stage multi-layer separation tower distillation method to thoroughly remove impurities such as hydrogen, nitrogen, oxygen, ammonia, metals, etc. in a silane and disilane mixed gas, so that the total impurity content is less than 1ppm, and silane and disilane gases with a purity of 99.9999% or above are obtained at the same time. The device of the present invention mainly comprises a multi-layer adsorption tower (5), a regeneration gas storage tank (16), a multi-layer separation tower (23), a silane product storage tank (28) and a disilane product storage tank (35). The device of the present invention is suitable for the separation of two substances with a boiling point difference of 30°C or above, and is particularly suitable for the separation of silane and disilane. The present invention simultaneously obtains high-purity silane and disilane with a purity of 99.9999% or above. The method is easy to realize industrial production.

Description

Technical Field

[0001] The invention relates to a purification method, a device and application for efficiently obtaining silane and disilane, and belongs to the technical field of gas purification. Background Art

[0002] With the rapid development of my country's ultra-large-scale integrated circuits, flat panel displays, photovoltaic power generation and other industries, the demand for electronic gases has increased significantly. At present, my country's annual imports of semiconductor chips have far exceeded the imports of crude oil. At the same time, chips are widely used, and excessive dependence on imports undoubtedly poses a greater threat to my country's security. At present, disilane production is mainly concentrated in the United States, France and Japan. Most of the silane and disilane in China now rely on imports. The purity of domestic assets is low, which is difficult to meet the needs of high-end processes and has become a soft rib that is stuck in the neck.

[0003] At present, various purification methods of silane and disilane have been disclosed in existing literature or patents. In the patent 202220066064.1 applied by Yantai Wanhua Electronic Materials Co., Ltd. in 2002, it was proposed to use an adsorption tower and a condensation device to treat a small batch of silane and disilane mixed gas prepared by the silicon-magnesium method. In the patent 201520817748.0 applied by Nanjing Yagertai New Energy Materials Co., Ltd. in 2015, it was proposed to obtain disilane by secondary cryogenic distillation. The patent 202011274073.1 applied by Shenzhen Bochun Semiconductor Materials Co., Ltd. in 2020 proposed to prepare disilane by chemical reaction. The patent 202022131754.4 applied by Nanjing Yagertai New Energy Materials Co., Ltd. in 2020 proposed to obtain disilane by three-stage cryogenic distillation. The above methods can remove impurities such as ammonia, silane, and hydrogen to a certain extent, but they are all secondary or tertiary distillation, with complex processes, difficult operations, and low efficiency. In addition, silane itself has utilization value but is not recycled, and the product purity is difficult to reach 99.999% or above. Summary of the invention

[0004] In view of this, the purpose of the present invention is to provide a purification method and device for efficiently obtaining silane and disilane, by sequentially passing a mixed gas with a silane content of 30% to 60% through a multi-layer adsorption tower for adsorption and a multi-layer separation tower for rectification. The impurities such as water, ammonia, carbon monoxide, carbon dioxide and methane in the mixed gas of silane and disilane are thoroughly removed by a single-stage multi-layer adsorption combined with a first-stage multi-layer separation, so that the total impurity content is less than 1ppm. The raw material bottle of the silane and disilane mixed gas enters the multi-layer adsorption tower and the multi-layer separation tower in turn through a multi-layer adsorption tower feed flowmeter, a multi-layer adsorption tower feed regulating valve, and a multi-layer adsorption tower feed pipeline, and undergoes single-stage multi-layer adsorption and first-stage multi-layer separation, and simultaneously obtains high-purity silane and disilane with a purity of 99.9999% or above. The method is easy to implement industrial production.

[0005] The purpose of the present invention is achieved by the following technical solutions:

[0006] A purification method for efficiently obtaining silane and disilane, characterized in that it comprises the following steps:

[0007] S1, set the temperature of the multi-layer adsorption tower, regeneration gas storage tank, multi-layer separation tower, silane product storage tank and disilane product storage tank to 100-200°C, then use inert gas to replace the entire device, and then evacuate to -0.099Mpa or below;

[0008] S2, open the outlet valve of the silane and disilane mixed gas raw material bottle, and pass the mixed raw material gas with a silane content of 30% to 60% into the multilayer adsorption tower through the multilayer adsorption tower feed flow meter and the multilayer adsorption tower feed regulating valve to perform adsorption operation; the intake flow rate is 0 to 40 kg / h;

[0009] S3, the gas adsorbed by the multi-layer adsorption tower passes through the separation tower filter, separation tower flow meter, separation tower regulating valve and separation tower pipeline in sequence and enters the multi-layer separation tower, with a flow rate of 0 to 40 kg / h;

[0010] S4, after being purified by the multi-layer separation tower, the high-purity silane is collected into the silane product storage tank through the silane collection pipeline, the silane collection flowmeter, the silane collection regulating valve and the silane collection filter, with a collection flow rate of 0 to 18 kg / h;

[0011] High-purity disilane is collected into the disilane product storage tank through the disilane collection pipeline, through the disilane collection flowmeter, the disilane collection regulating valve and the disilane collection filter in sequence, and the collection flow rate is 0-18 kg / h;

[0012] The silane product storage tank is equipped with a silane product storage tank analysis pipeline, and the disilane product storage tank is equipped with a disilane product storage tank analysis pipeline. The two analysis pipelines are used to analyze and detect silane and disilane;

[0013] The impurities enriched at the top of the multi-layer separation tower are discharged to the recovery tank through the light removal pipeline at the top of the multi-layer separation tower and the light removal regulating valve at the top of the multi-layer separation tower;

[0014] The impurities enriched in the bottom of the multi-layer separation tower are discharged to the recovery tank through the bottom deweighting pipeline and the regulating valve of the bottom deweighting pipeline of the multi-layer separation tower.

[0015] Preferably, the method further comprises the following steps: S5, regenerating the multilayer adsorption tower after running for 30 days, with a regeneration temperature of 250-300° C. and a regeneration time of 3-6 hours;

[0016] The regeneration step includes: turning on the multi-layer adsorption tower heating device, blowing hot nitrogen through the adsorption tower regeneration hot nitrogen pipeline to regenerate the adsorption tower, collecting the desorbed crude gas into a regeneration gas storage tank through the multi-layer adsorption tower regeneration gas outlet pipeline and the multi-layer adsorption tower regeneration gas outlet regulating valve, after the collection is completed, the gas in the regeneration gas storage tank can be heated by the regeneration gas storage tank heating device, and the gas in the storage tank is discharged through the regeneration gas storage tank to the multi-layer adsorption tower pipeline and the regeneration gas storage tank to the multi-layer adsorption tower regulating valve and re-enters the adsorption tower for adsorption.

[0017] Preferably, the inert gas in step S1 is one or more of nitrogen, argon or helium, and the purity of the gas used is 99.999% or above; the number of inert gas replacements is 3 to 5 times, and the replacement temperature is 100 to 150° C.; after treatment, the water content of the entire device is less than 0.01 ppm.

[0018] Preferably, the silane content in the mixed raw material gas in step S2 is 40% to 50%, the air intake flow rate is 20 to 40 kg / h, the working pressure of the multilayer adsorption tower is 0.2 to 1.5 MPa, and the working temperature of the multilayer adsorption tower is 80 to 350° C.

[0019] The working pressure of the multilayer separation tower in step S3 is 0.05 to 1.3 MPa, the working temperature of the separation tower is -30 to -100°C, the liquid level is 1500 to 2500 mm, and the heating power is 40 to 50 KW.

[0020] Preferably, the multilayer separation tower in step S3 has an operating temperature of -45 to -100°C, an operating pressure of 0.1 to 1.3 MPa, a heating power of 40 to 45 KW, and a feed flow rate of 18 to 38 kg / h.

[0021] Preferably, the silane collection flow rate in step S4 is 8 to 17 kg / h, and the disilane collection flow rate is 8 to 17 kg / h;

[0022] The regeneration time of the multilayer adsorption tower in step S5 is 4 hours, and the regeneration temperature is 260-290°C.

[0023] A purification device, characterized in that it comprises a mixed gas raw material bottle, a multi-layer adsorption tower, a regeneration gas storage tank, a multi-layer separation tower, a silane product storage tank and a disilane product storage tank;

[0024] The mixed gas raw material bottle and the multi-layer adsorption tower are connected through a multi-layer adsorption tower feed pipeline, and a multi-layer adsorption tower feed flowmeter and a multi-layer adsorption tower feed regulating valve are sequentially arranged on the multi-layer adsorption tower feed pipeline, and the multi-layer adsorption tower feed pipeline is connected to the multi-layer adsorption tower feed port, and the multi-layer adsorption tower feed port is also connected to an adsorption tower regeneration hot nitrogen pipeline; the multi-layer adsorption tower is provided with a multi-layer adsorption tower heating device;

[0025] The discharge port of the multi-layer adsorption tower is connected to the multi-layer separation tower through a separation tower pipeline, and a separation tower filter, a separation tower flow meter and a separation tower regulating valve are sequentially arranged on the separation tower pipeline;

[0026] The top of the multi-layer adsorption tower is connected to the regeneration gas storage tank through the multi-layer adsorption tower regeneration gas outlet pipeline, and a multi-layer adsorption tower regeneration gas outlet regulating valve is arranged on the multi-layer adsorption tower regeneration gas outlet pipeline. The regeneration gas storage tank is connected to the multi-layer adsorption tower feed port through the multi-layer adsorption tower pipeline, and a multi-layer adsorption tower regulating valve is arranged on the multi-layer adsorption tower pipeline; a regeneration gas storage tank heating device and a regeneration gas storage tank refrigerant jacket are arranged on the regeneration gas storage tank; a regeneration gas storage tank vacuum pipeline and a regeneration gas storage tank analysis pipeline are arranged on the regeneration gas storage tank, a regeneration gas storage tank vacuum valve is arranged on the regeneration gas storage tank vacuum pipeline, and a regeneration gas storage tank analysis valve is arranged on the regeneration gas storage tank analysis pipeline;

[0027] The upper end of the multilayer separation tower is connected to the silane product storage tank through a silane collection pipeline, and the silane collection pipeline is sequentially provided with a silane collection flowmeter, a silane collection regulating valve, and a silane collection filter; the upper end of the multilayer separation tower is provided with a multilayer separation tower thermometer, a multilayer separation tower pressure gauge, a multilayer separation tower top refrigerant inlet pipeline, and a multilayer separation tower top refrigerant outlet pipeline; the top of the multilayer separation tower is provided with a multilayer separation tower top light removal pipeline, and the multilayer separation tower top light removal regulating valve is provided on the multilayer separation tower top light removal pipeline; the multilayer separation tower top light removal pipeline is connected to a recovery tank; the silane product storage tank is provided with a silane product storage tank refrigerant jacket and a silane product storage tank heating device; the silane product storage tank is connected to a silane product storage tank analysis pipeline, and the silane product storage tank analysis pipeline is provided with a silane product storage tank analysis valve;

[0028] A multilayer separation tower heating device and a multilayer separation tower liquid level meter are arranged at the bottom of the multilayer separation tower, and a multilayer separation tower bottom deweighting pipeline is also connected to the bottom of the multilayer separation tower, and a multilayer separation tower bottom deweighting pipeline regulating valve is arranged on the multilayer separation tower bottom deweighting pipeline; the lower part of the multilayer separation tower is connected to the disilane product storage tank through a disilane collecting pipeline, and a disilane collecting flowmeter, a disilane collecting regulating valve and a disilane collecting filter are arranged on the disilane collecting pipeline in sequence; a disilane product storage tank refrigerant jacket and a disilane product storage tank heating device are arranged on the disilane product storage tank, and the disilane product storage tank is connected to a disilane product storage tank analysis pipeline, and a disilane product storage tank analysis valve is arranged on the disilane product storage tank analysis pipeline.

[0029] Preferably, the multi-layer adsorption tower has a working pressure of 0.2-1.5 Mpa, a height of 8-10 m, and is provided with 4 layers of fillers, each layer of which is 2-2.5 m high; each layer of fillers is composed of four parts, namely silica gel, γ-alumina, carbon nanotubes and molecular sieves, wherein the silica gel particle size is 3-5 mm, the γ-alumina particle size is 2-4 mm, the carbon nanotube particle size is 2-3 mm, and the molecular sieve particle size is 1-2 mm; the ratio of the four parts of the adsorption tower is 3:1:2:2, and the four fillers are arranged regularly from bottom to top;

[0030] The refrigerant in the refrigerant jacket of the storage tank is one of liquid nitrogen and dichloromethane; the feed flow rate of the multi-layer separation tower is 0-40 kg / h, the height of the separation tower is 30-40 m, the diameter of the separation tower column is 0.5-0.8 m, the liquid level of the separation tower is 1500-2500 mm, the pressure of the separation tower is 0.05-1.3 MPa, the temperature of the separation tower is -30--100 ° C, and the heating power at the bottom of the separation tower is 40-50 KW.

[0031] Preferably, the inlet of the pipeline from the multi-layer adsorption tower to the separation tower is located 15 to 20 meters above the kettle of the multi-layer separation tower, and there are three inlets on the same horizontal plane with an included angle of 120°;

[0032] The height of the top condenser of the multilayer separation tower is 2 to 3 meters, and the diameter is 0.5 to 1 meter; the silane collection pipeline at the top of the separation tower is located 1.5 to 2 meters away from the top of the tower, and the production flow rate is 0 to 18 kg / h;

[0033] The height of the multi-layer separation tower kettle is 2-3m, the diameter is 1-2m, the disilane collection pipeline of the separation tower kettle is located 2.5-3m from the bottom of the kettle, and the production flow rate is 0-18kg / h;

[0034] Both the silane collection filter and the disilane collection filter are 2.5nm high-precision filters, and the roughness of the inner wall of the filter is less than 0.2um;

[0035] The multi-layer adsorption tower, multi-layer separation tower, regeneration gas storage tank, silane product storage tank and disilane product storage tank are made of one of 316L stainless steel and monel alloy, and the inner wall of all equipment must be electrochemically polished, and the inner wall roughness is less than 0.2um;

[0036] The filler in the multi-layer separation tower is one of the θ rings, ball rings and Raschig rings, the diameter of the filler is 10-20 mm, and the material of the θ rings, ball rings and Raschig rings is independently one of stainless steel, monel alloy, nickel, polytetrafluoroethylene and alumina ceramics.

[0037] Preferably, there are two multi-layer adsorption towers and two regeneration gas storage tanks, one of which is used as a spare.

[0038] The application of the purification device is suitable for the separation of two substances with a boiling point difference of 30°C or more, preferably suitable for the separation of silane and disilane.

[0039] Beneficial effects of the present invention:

[0040] The method adopts a single-stage multi-layer adsorption combined with a first-stage multi-layer separation tower distillation method to thoroughly remove impurities such as hydrogen, nitrogen, oxygen, ammonia, and metals in the silane and disilane mixed gas, so that the total impurity content is less than 1ppm, and at the same time, silane and disilane gases with a purity of 99.9999% or above are obtained. The method improves the adsorption efficiency and distillation efficiency, and one-step adsorption and distillation can simultaneously obtain two high-purity products. The method reduces raw material consumption and waste gas emissions, and improves raw material utilization; all equipment of the device is polished and the roughness is less than 0.2um, and all pipes and fittings are EP grade, which reduces the residual air and moisture in the pipeline, improves the sealing performance of the entire system, and reduces the safety risk of the process; at the same time, it occupies a small area, reduces the construction and production costs; the operation is simple, and it is convenient for later maintenance and processing. The raw material 1 enters the multi-layer adsorption tower 5 and the multi-layer separation tower 23 in sequence through the pipeline 3, the flow meter 42 and the flow control valve 2, and is subjected to single-stage multi-layer adsorption and first-stage multi-layer separation tower distillation, and high-purity silane and disilane with a purity of 99.9999% or above are obtained at the same time. The method is easy to realize industrial production.

[0041] (1) The purification method and device for efficiently obtaining silane and disilane of the present invention have simple process and strong operability, and can obtain two products of high-purity silane and disilane through one-stage adsorption and one-step distillation. Under the condition of the same impurity content, the process requires less equipment, and can simultaneously obtain two high-purity gases of silane and disilane through purification, which is easy to realize industrial production;

[0042] (2) The method and apparatus for efficiently obtaining the purification of silane and disilane described in the present invention, wherein the design of the single-stage multi-layer adsorption tower and the selection and proportion of the filler reduce the adsorption of silane and disilane, adsorb all the difficult-to-remove ammonia, reduce the difficulty of distillation in the subsequent first-stage multi-layer separation tower, and improve the distillation efficiency.

[0043] (3) The method and device for efficiently obtaining the purification of silane and disilane described in the present invention arranges the feed inlet of the multilayer separation tower into three independent inlets on the same horizontal plane and at an angle of 120°, thereby avoiding uneven feed caused by the large diameter of the separation tower column, thereby affecting the distillation effect of a certain section of the filler. The method improves the distillation capacity and efficiency of the separation tower.

[0044] (4) The method and device for efficiently obtaining the purification of silane and disilane described in the present invention removes impurities such as water, ammonia, carbon monoxide, carbon dioxide and methane from the mixed gas of silane and disilane by single-stage multi-layer adsorption combined with single-stage multi-layer separation and purification, so that the total impurity content is less than 1ppm, and obtains silane and disilane with a purity of 99.9999% or above. The method is easy to realize industrial production.

[0045] (5) The method and apparatus for efficiently obtaining the purification of silane and disilane described in the present invention can achieve efficient simultaneous production of high-purity silane and disilane by optimizing the height of the multi-layer separation tower, the selection of fillers, the setting of the feed port, the design of the heating power, etc.

[0046] (6) In the method and apparatus for efficiently obtaining the purification of silane and disilane described in the present invention, all equipment and pipelines are electrochemically polished, with a roughness of less than 0.2 um, which improves the cleanliness of the equipment, reduces the difficulty of equipment processing, and improves the safety performance of the system during the production process. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 A schematic diagram of a purification method and device for efficiently obtaining silane and disilane;

[0048] Among them, 1-silane and disilane mixed gas raw material bottle, 42-multi-layer adsorption tower feed flowmeter, 2-multi-layer adsorption tower feed regulating valve, 3-multi-layer adsorption tower feed pipeline, 4-adsorption tower regeneration hot nitrogen pipeline, 5-multi-layer adsorption tower, 6-multi-layer adsorption tower heating device, 7-multi-layer adsorption tower regeneration outlet pipeline, 8-multi-layer adsorption tower regeneration outlet regulating valve, 48-multi-layer adsorption tower discharge to separation tower filter, 43-multi-layer adsorption tower discharge to separation tower flowmeter, 18-multi-layer adsorption tower discharge to separation tower regulating valve, 1 9-pipeline from multi-layer adsorption tower discharge to separation tower, 16-regeneration gas storage tank, 17-regeneration gas storage tank heating device, 15-regeneration gas storage tank refrigerant jacket, 11-regeneration gas storage tank vacuum valve, 12-regeneration gas storage tank vacuum pipeline, 13-regeneration gas storage tank analysis valve, 14-regeneration gas storage tank analysis pipeline, 9-regeneration gas storage tank discharge to multi-layer adsorption tower pipeline, 10-regeneration gas storage tank discharge to multi-layer adsorption tower regulating valve, 21-multi-layer separation tower bottom deweighting pipeline, 20-multi-layer separation tower bottom deweighting pipeline regulating valve, 22-multi-layer separation tower heating device, 51-multi-layer separation tower liquid level gauge, 23-multi-layer separation tower, 49-multi-layer separation tower top refrigerant inlet pipeline, 50-multi-layer separation tower top refrigerant outlet pipeline, 41-multi-layer separation tower thermometer, 40-multi-layer separation tower pressure gauge, 24-multi-layer separation tower top light removal pipeline, 25-multi-layer separation tower top light removal regulating valve, 45-silane collection flowmeter, 26-silane collection regulating valve, 27-silane collection pipeline, 46-silane collection filter, 28-silane product storage Tank, 29-silane product storage tank refrigerant jacket, 30-silane product storage tank heating device, 32-silane product storage tank analysis pipeline, 31-silane product storage tank analysis valve, 44-disilane collection flowmeter, 33-disilane collection regulating valve, 47-disilane collection filter, 34-disilane collection pipeline, 35-disilane product storage tank, 36-disilane product storage tank refrigerant jacket, 37-disilane product storage tank heating device, 39-disilane product storage tank analysis pipeline, 38-disilane product storage tank analysis valve. DETAILED DESCRIPTION

[0049] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments, but is not limited thereto.

[0050] The schematic diagram of a purification device for efficiently obtaining silane and disilane in the following embodiments is as follows: Figure 1As shown, the device mainly includes: a silane and disilane mixed gas raw material bottle 1, a multi-layer adsorption tower feed flowmeter 42, a multi-layer adsorption tower feed regulating valve 2, a multi-layer adsorption tower feed pipeline 3, an adsorption tower regeneration hot nitrogen pipeline 4, a multi-layer adsorption tower 5, a multi-layer adsorption tower heating device 6, a multi-layer adsorption tower regeneration outlet pipeline 7, a multi-layer adsorption tower regeneration outlet regulating valve 8, a multi-layer adsorption tower discharge to a separation tower filter 48, a multi-layer adsorption tower discharge to a separation tower flowmeter 43, a multi-layer adsorption tower discharge to a separation tower Tower regulating valve 18, multi-layer adsorption tower discharge to separation tower pipeline 19, regeneration gas storage tank 16, regeneration gas storage tank heating device 17, regeneration gas storage tank refrigerant jacket 15, regeneration gas storage tank vacuum valve 11, regeneration gas storage tank vacuum pipeline 12, regeneration gas storage tank analysis valve 13, regeneration gas storage tank analysis pipeline 14, regeneration gas storage tank discharge to multi-layer adsorption tower pipeline 9, regeneration gas storage tank discharge to multi-layer adsorption tower regulating valve 10, multi-layer separation tower bottom deweighting pipeline 21, multi-layer separation tower bottom deweighting pipeline Regulating valve 20, multi-layer separation tower heating device 22, multi-layer separation tower liquid level gauge 51, multi-layer separation tower 23, multi-layer separation tower top refrigerant inlet pipeline 49, multi-layer separation tower top refrigerant outlet pipeline 50, multi-layer separation tower thermometer 41, multi-layer separation tower pressure gauge 40, multi-layer separation tower top light removal pipeline 24, multi-layer separation tower top light removal regulating valve 25, silane collection flowmeter 45, silane collection regulating valve 26, silane collection pipeline 27, silane collection filter 46, silane product Storage tank 28, silane product storage tank refrigerant jacket 29, silane product storage tank heating device 30, silane product storage tank analysis pipeline 32, silane product storage tank analysis valve 31, disilane collection flowmeter 44, disilane collection regulating valve 33, disilane collection filter 47, disilane collection pipeline 34, disilane product storage tank 35, disilane product storage tank refrigerant jacket 36, disilane product storage tank heating device 37, disilane product storage tank analysis pipeline 39 and disilane product storage tank analysis valve 38.

[0051] The silane and disilane mixed gas raw material cylinder 1 is connected to the multilayer adsorption tower 5 through the multilayer adsorption tower feed flowmeter 42, the multilayer adsorption tower feed regulating valve 2, and the multilayer adsorption tower feed pipeline 3; the bottom of the multilayer adsorption tower is provided with an adsorption tower regeneration hot nitrogen pipeline 4 for purging hot nitrogen during regeneration. The multilayer adsorption tower is provided with a multilayer adsorption tower heating device 6 for heating the adsorption tower during regeneration and treatment. The top of the adsorption tower is connected to the regeneration gas storage tank 16 through the multilayer adsorption tower regeneration outlet pipeline 7 and the multilayer adsorption tower regeneration outlet regulating valve 8. The top of the adsorption tower is connected to the multilayer separation tower 23 through the multilayer adsorption tower discharge to the separation tower filter 48, the multilayer adsorption tower discharge to the separation tower flowmeter 43, the multilayer adsorption tower discharge to the separation tower regulating valve 18 and the multilayer adsorption tower discharge to the separation tower pipeline 19.

[0052] The multi-layer separation tower is provided with a refrigerant inlet pipeline 49 and a refrigerant outlet pipeline 50 at the top to provide a cold source for the multi-layer separation tower 23; the multi-layer separation tower is provided with a pressure gauge 40, a thermometer 41, and a liquid level gauge 51 to monitor the multi-layer separation tower; and a heating device 22 is provided at the bottom of the multi-layer separation tower. The multi-layer separation tower is connected to the silane product storage tank 28 through the top silane collection flowmeter 45, the silane collection regulating valve 26, the silane collection pipeline 27, and the silane collection filter 46; the multi-layer separation tower is connected to the disilane product storage tank 35 through the kettle part disilane collection flowmeter 44, the disilane collection regulating valve 33, the disilane collection pipeline 34, and the disilane collection filter 47; the multi-layer separation tower top light removal pipeline 24 set at the top of the multi-layer separation tower and the separation tower bottom heavy removal pipeline set at the bottom can discharge the gas with high impurity content to the recovery tank.

[0053] The regeneration gas storage tank 16 is provided with a regeneration gas storage tank vacuum valve 11, a regeneration gas storage tank vacuum pipeline 12, a regeneration gas storage tank analysis valve 13, a regeneration gas storage tank analysis pipeline 14, a regeneration gas storage tank heating device 17, and a regeneration gas storage tank refrigerant jacket 15; the regeneration gas storage tank 16 is connected to the multi-layer adsorption tower 5 through the regeneration gas storage tank discharge to multi-layer adsorption tower pipeline 9 and the regeneration gas storage tank discharge to multi-layer adsorption tower regulating valve 10.

[0054] The silane product storage tank 29 is provided with a silane product storage tank analysis pipeline 32, a silane product storage tank analysis valve 31, a silane product storage tank refrigerant jacket 29 and a silane product storage tank heating device 30. The disilane product storage tank 35 is provided with a silane product storage tank analysis pipeline 39, a silane product storage tank analysis valve 38, a silane product storage tank refrigerant jacket 36 and a silane product storage tank heating device 37. The analysis pipeline is used to analyze the gas impurity content in the product storage tank, and the heating device is used for transferring materials or filling.

[0055] A purification method for efficiently obtaining silane and disilane has the following specific steps:

[0056] (1) First, the entire device is replaced with an inert gas for 3 to 5 times at a replacement temperature of 65 to 250°C. After the treatment, the water content of the entire device is less than 0.01 ppm, and then the device is evacuated to -0.099 MPa or below;

[0057] (2) Open the outlet valve of the silane and disilane mixed gas raw material bottle 1, and pass the mixed raw material gas into the multilayer adsorption tower 5 through the multilayer adsorption tower feed flowmeter 42 and the multilayer adsorption tower feed regulating valve 2, with a flow rate of 0-40 kg / h. Through the multilayer adsorption tower adsorption, all ammonia impurities are removed, and some impurities such as hydrogen, carbon dioxide and methane are removed. The working pressure of the multilayer adsorption tower is 0.2-1.5 MPa, the height of the adsorption tower is 8-10 m, and the multilayer adsorption tower is provided with 4 layers of fillers, each layer of fillers is 2-2.5 m high. Each layer of fillers is composed of four parts, namely silica gel, γ-alumina, carbon nanotubes and molecular sieves, wherein the silica gel particle size is 3-5 mm, the γ-alumina particle size is 2-4 mm, the carbon nanotube particle size is 2-3 mm, and the molecular sieve particle size is 1-2 mm. The ratio of the four parts of the adsorption tower is 3:1:2:2, and the four fillers are arranged regularly from bottom to top. The outer wall of the adsorption is provided with a heating system, and the heating temperature is 80-350 ° C

[0058] (3) The gas adsorbed by the multilayer adsorption tower 5 enters the multilayer separation tower 23 through the multilayer adsorption tower discharge to the separation tower filter 48, the multilayer adsorption tower discharge to the separation tower flowmeter 43, the multilayer adsorption tower discharge to the separation tower regulating valve 18 and the multilayer adsorption tower discharge to the separation tower pipeline 19, with a flow rate of 0 to 40 kg / h, and the feed port is located 15 to 20 m above the tower kettle of the separation tower. The tower height is 30 to 40 m, the top condenser height is 2 to 3 m, and the diameter is 0.5 to 1 m. The top of the separation tower is provided with a multilayer separation tower thermometer 41 and a multilayer separation tower pressure gauge 40 for monitoring the temperature and pressure of the multilayer separation tower. The working pressure is 0.05~1.3Mpa, the working temperature is -30~-100℃, and a silane collection pipeline 27 is provided at the top of the separation tower. The silane is collected to the silane product storage tank 28 through a silane collection flowmeter 45, a silane collection regulating valve 26, and a silane collection filter 46. The silane collection pipeline is located 1.5~2m away from the top of the tower, and the collection flow rate is 0~18kg / h. A multi-layer separation tower top light removal pipeline 24 and a multi-layer separation tower top light removal regulating valve 25 are provided at the top of the separation tower. The light component is discharged to the recovery tank by controlling the opening of the regulating valve. The separation tower is provided with a multi-layer separation tower top refrigerant inlet pipeline 49 and a multi-layer separation tower top refrigerant outlet pipeline 50, wherein the refrigerant is one of liquid nitrogen and dichloromethane. The tower kettle has a height of 2 to 3 m and a diameter of 1 to 2 m. The tower kettle is provided with a multi-layer separation tower liquid level gauge 51, with a liquid level of 1500 to 2500 mm. The bottom is provided with a multi-layer separation tower heating device 22 with a heating power of 40 to 50 kW. The separation tower kettle is provided with a disilane collection pipeline 34, a disilane collection flowmeter 44, a disilane collection regulating valve 33, and a disilane collection filter 47, which are collected to a disilane product storage tank 35, wherein the disilane collection pipeline is located 2.5 to 3 m above the bottom of the kettle, and the collection flow is 0 to 18 kg / h. The separation tower kettle is provided with a multi-layer separation tower bottom deweighting pipeline 21 and a multi-layer separation tower bottom deweighting pipeline regulating valve 20, and the heavy component is discharged to the recovery tank for recovery by controlling the opening of the regulating valve.

[0059] (4) Silane products are collected into silane product storage tank 28 via silane collection pipeline 27. The silane product storage tank is provided with a silane product storage tank analysis pipeline 32 for product analysis, and a silane product storage tank analysis valve 31 is provided on the analysis pipeline. Disilane products are collected into disilane product storage tank 35 via disilane collection pipeline 34. The disilane product storage tank is provided with a disilane product storage tank analysis pipeline 39 for product analysis, and a disilane product storage tank analysis valve 38 is provided on the analysis pipeline. Both silane and disilane product storage tanks are provided with refrigerant jackets 29 and 36, and the refrigerant used is one of liquid nitrogen and dichloromethane. Heating devices 30 and 37 are provided at the bottom of the silane and disilane product storage tanks for heating the storage tanks.

[0060] (5) After the multilayer adsorption tower 5 is saturated with adsorption, it needs to be regenerated. The multilayer adsorption tower heating device 6 is turned on, and the hot nitrogen is purged through the adsorption tower regeneration hot nitrogen pipeline 4 to regenerate the adsorption tower, and the desorbed crude gas is collected to the regeneration gas storage tank 16 through the multilayer adsorption tower regeneration gas outlet pipeline 7 and the multilayer adsorption tower regeneration gas outlet regulating valve 8. After the collection is completed, the gas in the regeneration gas storage tank can be heated by the regeneration gas storage tank heating device 17, and the gas in the storage tank can be discharged from the regeneration gas storage tank to the multilayer adsorption tower pipeline 9 and the regeneration gas storage tank to the multilayer adsorption tower regulating valve 10 and enter the adsorption tower again for adsorption.

[0061] The inert gas is one or more of nitrogen, helium and argon, with a purity greater than or equal to 99.999%, and the inert gas must be purified by a purifier before use to ensure that the water content in the inert gas is less than 5 ppb;

[0062] The silane content in the raw mixed gas is 30% to 60%, and the device can simultaneously obtain two products, 99.9999% or higher high-purity silane and disilane. The device is also suitable for separating two substances with large boiling point differences in other mixed gases, and can also obtain high-purity gas with a purity of 99.9999% or higher. The difference in boiling points of the two substances is required to be 30°C or higher.

[0063] Example 1

[0064] A purification method for efficiently obtaining silane and disilane:

[0065] The multi-layer adsorption tower, multi-layer separation tower and storage tank are made of 316L stainless steel and the inner wall is electrochemically polished with a roughness of less than 0.2um.

[0066] The adsorption tower is 8m high and is equipped with 4 layers of fillers, each layer of which is 2m high. Each layer of fillers is composed of four parts, namely silica gel, γ-alumina, carbon nanotubes and molecular sieves, of which the silica gel particle size is 3mm, the γ-alumina particle size is 2mm, the carbon nanotube particle size is 2mm, and the molecular sieve particle size is 1mm. The ratio of the four parts of adsorbent is 3:1:2:2;

[0067] The multi-layer separation tower is 30m high, the separation tower packing is made of stainless steel θ ring, the packing diameter is 10mm, the separation tower column diameter is 0.5m, the inlet of the multi-layer adsorption tower discharge to the separation tower pipeline is located 15m above the separation tower kettle, there are 3 inlets on the same horizontal plane and the included angle is 120°. The height of the top condenser of the separation tower is 2m and the diameter is 0.5m. The silane collection pipeline at the top of the separation tower is located 1.5m away from the top of the tower. The separation tower kettle is 2m high and 1m in diameter, and the disilane collection pipeline of the separation tower kettle is located 2.5m away from the bottom of the kettle.

[0068] The silane content of the silane and disilane mixed gas raw material is 40%, and the impurities are difficult-to-separate water, ammonia, carbon monoxide, carbon dioxide, methane and other impurities. The specific steps are as follows:

[0069] (1) The temperature of the multi-layer adsorption tower, the regeneration gas storage tank, the multi-layer separation tower, the silane product storage tank and the disilane product storage tank was set to 100°C, and then the entire device was replaced with nitrogen for 3 times. After the treatment, the water content of the entire device was 0.01ppm, and then it was evacuated to -0.099Mpa;

[0070] (2) Open the outlet valve of the silane and disilane mixed gas raw material bottle, and feed the mixed raw material gas with 40% silane content into the multilayer adsorption tower through the multilayer adsorption tower feed flow meter and the multilayer adsorption tower feed regulating valve to perform adsorption operation. The air intake flow rate is 20kg / h, and the multilayer adsorption tower working pressure is 0.2Mpa.

[0071] (3) The gas adsorbed by the multi-layer adsorption tower enters the multi-layer separation tower through the multi-layer adsorption tower discharge to separation tower filter, the multi-layer adsorption tower discharge to separation tower flow meter, the multi-layer adsorption tower discharge to separation tower regulating valve and the multi-layer adsorption tower discharge to separation tower pipeline, with a flow rate of 18kg / h. The working pressure of the multi-layer separation tower is 0.1Mpa, the working temperature of the separation tower is -45°C, the liquid level is 1500mm, and the heating power is 40KW.

[0072] (4) After purification by the multi-layer separation tower, high-purity silane is collected into the silane product storage tank through the silane collection pipeline, the silane collection flowmeter, the silane collection regulating valve, and the silane collection filter, with a collection flow rate of 8 kg / h; high-purity disilane is collected into the disilane product storage tank through the disilane collection pipeline, the disilane collection flowmeter, the disilane collection regulating valve, and the disilane collection filter, with a collection flow rate of 8 kg / h.

[0073] (5) The gas obtained in step (4) is stored in silane and disilane product storage tanks. According to the analysis of the product storage tanks, the impurity content of ammonia, water, oxygen, nitrogen and methane in silane is 0.8ppm, and the impurity content in disilane is 0.7ppm. The device finally obtains silane with a purity of 99.99992% and disilane with a purity of 99.99993%.

[0074] Example 2

[0075] A purification method for efficiently obtaining silane and disilane:

[0076] The multi-layer adsorption tower, multi-layer separation tower and storage tank are made of monel alloy and the inner wall is electrochemically polished with a roughness of less than 0.2um.

[0077] The adsorption tower is 10m high and is equipped with 4 layers of fillers, each layer of which is 2.5m high. Each layer of fillers is composed of four parts, namely silica gel, γ-alumina, carbon nanotubes and molecular sieves, of which the silica gel particle size is 5mm, the γ-alumina particle size is 4mm, the carbon nanotube particle size is 3mm, and the molecular sieve particle size is 2mm. The ratio of the four parts of adsorbent is 3:1:2:2;

[0078] The multi-layer separation tower is 40m high, the separation tower packing is made of nickel ball ring, the packing diameter is 20mm, the separation tower column diameter is 0.8m, the inlet of the multi-layer adsorption tower discharge to the separation tower pipeline is located 20m above the separation tower kettle, there are 3 inlets on the same horizontal plane and the angle is 120°. The height of the top condenser of the separation tower is 3m and the diameter is 1.0m. The silane collection pipeline at the top of the separation tower is located 2.0m away from the top of the tower. The height of the separation tower kettle is 3m and the diameter is 2m. The disilane collection pipeline of the separation tower kettle is located 3m away from the bottom of the kettle.

[0079] The silane content of the silane and disilane mixed gas raw material is 50%, and the impurities are difficult-to-separate water, ammonia, carbon monoxide, carbon dioxide, methane and other impurities. The specific steps are as follows:

[0080] (1) The temperature of the multi-layer adsorption tower, the regeneration gas storage tank, the multi-layer separation tower, the silane product storage tank and the disilane product storage tank is set to 150° C., and then the entire device is replaced with nitrogen for 5 times. After the treatment, the water content of the entire device is 0.007 ppm, and then it is evacuated to -0.0995 MPa;

[0081] (2) Open the outlet valve of the silane and disilane mixed gas raw material bottle, and feed the mixed raw material gas with 50% silane content into the multilayer adsorption tower through the multilayer adsorption tower feed flow meter and the multilayer adsorption tower feed regulating valve to perform adsorption operation. The air intake flow rate is 40kg / h, and the multilayer adsorption tower working pressure is 1.5Mpa.

[0082] (3) The gas adsorbed by the multi-layer adsorption tower enters the multi-layer separation tower through the multi-layer adsorption tower discharge to separation tower filter, the multi-layer adsorption tower discharge to separation tower flow meter, the multi-layer adsorption tower discharge to separation tower regulating valve and the multi-layer adsorption tower discharge to separation tower pipeline, with a flow rate of 38kg / h. The working pressure of the multi-layer separation tower is 1.3Mpa, the working temperature of the separation tower is -100°C, the liquid level is 2500mm, and the heating power is 45KW.

[0083] (4) After purification by the multi-layer separation tower, high-purity silane is collected into the silane product storage tank through the silane collection pipeline, the silane collection flowmeter, the silane collection regulating valve, and the silane collection filter, with a collection flow rate of 18 kg / h; high-purity disilane is collected into the disilane product storage tank through the disilane collection pipeline, the disilane collection flowmeter, the disilane collection regulating valve, and the disilane collection filter, with a collection flow rate of 18 kg / h.

[0084] (5) The gas obtained in step (4) is stored in silane and disilane product storage tanks. According to the analysis of the product storage tanks, the impurity content of ammonia, water, oxygen, nitrogen and methane in silane is 0.9ppm, and the impurity content in disilane is 0.8ppm. The device finally obtains silane with a purity of 99.99991% and disilane with a purity of 99.99992%.

[0085] Example 3

[0086] A purification method for efficiently obtaining silane and disilane:

[0087] The multi-layer adsorption tower, multi-layer separation tower and storage tank are made of monel alloy and the inner wall is electrochemically polished with a roughness of less than 0.2um.

[0088] The adsorption tower is 9m high and is equipped with 4 layers of fillers, each layer of which is 2.3m high. Each layer of fillers is composed of four parts, namely silica gel, γ-alumina, carbon nanotubes and molecular sieves, of which the silica gel particle size is 4.5mm, the γ-alumina particle size is 3.5mm, the carbon nanotube particle size is 2.6mm, and the molecular sieve particle size is 1.8mm. The ratio of the four parts of adsorbent is 3:1:2:2;

[0089] The multi-layer separation tower is 35m high, and the separation tower filler is made of alumina Raschig rings with a filler diameter of 15mm. The separation tower column has a diameter of 0.7m. The inlet of the multi-layer adsorption tower discharge to the separation tower pipeline is located 18m above the separation tower kettle, and there are 3 inlets on the same horizontal plane with an angle of 120°. The height of the top condenser of the separation tower is 2.5m and the diameter is 0.8m. The silane collection pipeline at the top of the separation tower is located 1.8m away from the top of the tower. The height of the separation tower kettle is 2.5m and the diameter is 1.7m. The disilane collection pipeline of the separation tower kettle is located 2.8m away from the bottom of the kettle.

[0090] The silane content of the silane and disilane mixed gas raw material is 45%, and the impurities are difficult-to-separate water, ammonia, carbon monoxide, carbon dioxide, methane and other impurities. The specific steps are as follows:

[0091] (1) The temperature of the multi-layer adsorption tower, the regeneration gas storage tank, the multi-layer separation tower, the silane product storage tank and the disilane product storage tank was set to 125°C, and then the entire device was replaced with nitrogen for 4 times. After the treatment, the water content of the entire device was 0.009 ppm, and then it was evacuated to -0.0993 MPa;

[0092] (2) Open the outlet valve of the silane and disilane mixed gas raw material bottle, and feed the mixed raw material gas with a silane content of 45% into the multilayer adsorption tower through the multilayer adsorption tower feed flow meter and the multilayer adsorption tower feed regulating valve to perform adsorption operation. The air intake flow rate is 30kg / h, and the multilayer adsorption tower working pressure is 1.0Mpa.

[0093] (3) The gas adsorbed by the multi-layer adsorption tower enters the multi-layer separation tower through the multi-layer adsorption tower discharge to separation tower filter, the multi-layer adsorption tower discharge to separation tower flow meter, the multi-layer adsorption tower discharge to separation tower regulating valve and the multi-layer adsorption tower discharge to separation tower pipeline, with a flow rate of 28kg / h. The working pressure of the multi-layer separation tower is 0.7Mpa, the working temperature of the separation tower is -75°C, the liquid level is 2000mm, and the heating power is 42KW.

[0094] (4) After purification by the multi-layer separation tower, high-purity silane is collected into the silane product storage tank through the silane collection pipeline, the silane collection flowmeter, the silane collection regulating valve, and the silane collection filter, with a collection flow rate of 13 kg / h; high-purity disilane is collected into the disilane product storage tank through the disilane collection pipeline, the disilane collection flowmeter, the disilane collection regulating valve, and the disilane collection filter, with a collection flow rate of 13 kg / h.

[0095] (5) The gas obtained in step (4) is stored in silane and disilane product storage tanks. According to the analysis of the product storage tanks, the impurity content of ammonia, water, oxygen, nitrogen and methane in silane is 0.9ppm, and the impurity content in disilane is 0.7ppm. The device finally obtains silane with a purity of 99.99991% and disilane with a purity of 99.99993%.

[0096] The present invention includes but is not limited to the above embodiments. Any equivalent replacement or partial improvement made under the principle of the spirit of the present invention shall be deemed to be within the protection scope of the present invention.

Claims

1. A purification method for efficiently obtaining silane and disilane, characterized in that: The following steps are involved: S1, setting the temperature of the multilayer adsorption tower (5), the regeneration gas storage tank (16), the multilayer separation tower (23), the silane product storage tank (28) and the disilane product storage tank (35) to 100-200°C, then using an inert gas to replace the entire device, and then evacuating to -0.099 MPa or less; the multilayer adsorption tower (5) is provided with 4 layers of fillers, each layer of fillers has a height of 2-2.5 m; each layer of fillers is composed of four parts, namely silica gel, γ-alumina, carbon nanotubes and molecular sieves, wherein the silica gel particle size is 3-5 mm, the γ-alumina particle size is 2-4 mm, the carbon nanotube particle size is 2-3 mm, and the molecular sieve particle size is 1-2 mm; S2, open the outlet valve of the silane and disilane mixed gas raw material bottle (1), and introduce the mixed raw material gas with a silane content of 30% to 60% into the multilayer adsorption tower (5) through the multilayer adsorption tower feed flow meter (42) and the multilayer adsorption tower feed regulating valve (2) to perform adsorption operation; the air intake flow rate is 0 to 40 kg / h; S3, the gas adsorbed by the multi-layer adsorption tower passes through the separation tower filter (48), the separation tower flow meter (43), the separation tower regulating valve (18) and the separation tower pipeline (19) in sequence and enters the multi-layer separation tower (23), with a flow rate of 0-40 kg / h; S4, after being purified by the multi-layer separation tower, the high-purity silane is collected into the silane product storage tank (28) through the silane collection pipeline (27), the silane collection flowmeter (45), the silane collection regulating valve (26) and the silane collection filter (46), and the collection flow rate is 0-18 kg / h; High-purity disilane is collected in a disilane product storage tank (35) via a disilane collection pipeline (34) and sequentially passes through a disilane collection flowmeter (44), a disilane collection regulating valve (33) and a disilane collection filter (47). The collection flow rate is 0-18 kg / h. The silane product storage tank (28) is provided with a silane product storage tank analysis pipeline (32), and the disilane product storage tank (35) is provided with a disilane product storage tank analysis pipeline (39), and the two analysis pipelines are used for analyzing and detecting silane and disilane; The impurities enriched at the top of the multi-layer separation tower are discharged to a recovery tank through a light removal pipeline (24) at the top of the multi-layer separation tower and a light removal regulating valve (25) at the top of the multi-layer separation tower; The impurities enriched at the bottom of the multi-layer separation tower are discharged to the recovery tank through the bottom deweighting pipeline (21) and the regulating valve (20) of the bottom deweighting pipeline of the multi-layer separation tower.

2. A purification method for efficiently obtaining silane and disilane according to claim 1, characterized in that: The following steps are also included: S5, regenerating the multilayer adsorption tower (5) after running for 30 days, with a regeneration temperature of 250-300°C and a regeneration time of 3-6 hours; The regeneration step comprises: starting the multi-layer adsorption tower heating device (6), blowing hot nitrogen through the adsorption tower regeneration hot nitrogen pipeline (4) to regenerate the adsorption tower, collecting the desorbed crude gas into a regeneration gas storage tank (16) through the multi-layer adsorption tower regeneration gas outlet pipeline (7) and the multi-layer adsorption tower regeneration gas outlet regulating valve (8), and after the collection is completed, the gas in the regeneration gas storage tank can be heated by the regeneration gas storage tank heating device (17), and the gas in the storage tank can be discharged through the regeneration gas storage tank to the multi-layer adsorption tower pipeline (9) and the regeneration gas storage tank to the multi-layer adsorption tower regulating valve (10) to re-enter the adsorption tower for adsorption.

3. A purification method for efficiently obtaining silane and disilane according to claim 1, characterized in that: The inert gas in step S1 is one or more of nitrogen, argon or helium, and the purity of the gas used is 99.999% or above; the number of times of inert gas replacement is 3 to 5 times, and the replacement temperature is 100 to 150° C.; after treatment, the water content of the entire device is less than 0.01 ppm; In step S2, the silane content in the mixed raw material gas is 40% to 50%, the air intake flow rate is 20 to 40 kg / h, the working pressure of the multilayer adsorption tower is 0.2 to 1.5 MPa, and the working temperature of the multilayer adsorption tower is 80 to 350° C. The working pressure of the multilayer separation tower in step S3 is 0.05~1.3Mpa, the working temperature of the separation tower is -30~-100°C, the liquid level is 1500~2500mm, and the heating power is 40~50KW.

4. A purification method for efficiently obtaining silane and disilane according to claim 3, characterized in that: The multilayer separation tower in step S3 has an operating temperature of -45 to -100°C, an operating pressure of 0.1 to 1.3 MPa, a heating power of 40 to 45 KW, and a feed flow rate of 18 to 38 kg / h.

5. A purification method for efficiently obtaining silane and disilane according to claim 2, characterized in that: The silane collection flow rate of step S4 is 8-17 kg / h, and the disilane collection flow rate is 8-17 kg / h; The regeneration time of the multilayer adsorption tower in step S5 is 4 hours, and the regeneration temperature is 260-290°C.

6. A purification device for efficiently obtaining silane and disilane, characterized in that: It comprises a mixed gas raw material bottle (1), a multi-layer adsorption tower (5), a regeneration gas storage tank (16), a multi-layer separation tower (23), a silane product storage tank (28) and a disilane product storage tank (35); The mixed gas raw material bottle (1) and the multilayer adsorption tower (5) are connected via a multilayer adsorption tower feed pipeline (3); a multilayer adsorption tower feed flow meter (42) and a multilayer adsorption tower feed regulating valve (2) are sequentially arranged on the multilayer adsorption tower feed pipeline (3); the multilayer adsorption tower feed pipeline (3) is connected to a feed port of the multilayer adsorption tower (5); and an adsorption tower regeneration hot nitrogen pipeline (4) is also connected to the feed port of the multilayer adsorption tower (5); and a multilayer adsorption tower heating device (6) is arranged on the multilayer adsorption tower (5); The discharge port of the multi-layer adsorption tower (5) is connected to the multi-layer separation tower (23) via a separation tower pipeline (19), and a separation tower filter (48), a separation tower flow meter (43) and a separation tower regulating valve (18) are sequentially arranged on the separation tower pipeline (19); The top of the multilayer adsorption tower (5) is connected to a regeneration gas storage tank (16) via a multilayer adsorption tower regeneration gas outlet pipeline (7), and a multilayer adsorption tower regeneration gas outlet regulating valve (8) is provided on the multilayer adsorption tower regeneration gas outlet pipeline (7). The regeneration gas storage tank (16) is connected to the feed port of the multilayer adsorption tower (5) via a multilayer adsorption tower pipeline (9), and a multilayer adsorption tower regulating valve (10) is provided on the multilayer adsorption tower pipeline (9); a regeneration gas storage tank heating device (17) and a regeneration gas storage tank refrigerant jacket (15) are provided on the regeneration gas storage tank (16); a regeneration gas storage tank vacuum pipeline (12) and a regeneration gas storage tank analysis pipeline (14) are provided on the regeneration gas storage tank (16), a regeneration gas storage tank vacuum valve (11) is provided on the regeneration gas storage tank vacuum pipeline (12), and a regeneration gas storage tank analysis valve (13) is provided on the regeneration gas storage tank analysis pipeline (14); The upper end of the multilayer separation tower (23) is connected to the silane product storage tank (28) through a silane collection pipeline (27). The silane collection pipeline (27) is provided with a silane collection flowmeter (45), a silane collection regulating valve (26), and a silane collection filter (46) in sequence. The upper end of the multilayer separation tower (23) is provided with a multilayer separation tower thermometer (41), a multilayer separation tower pressure gauge (40), a multilayer separation tower top refrigerant inlet pipeline (49) and a multilayer separation tower top refrigerant outlet pipeline (50). The top of the multilayer separation tower (23) is provided with A multi-layer separation tower top light removal pipeline (24) is provided, and a multi-layer separation tower top light removal regulating valve (25) is provided on the multi-layer separation tower top light removal pipeline (24); the multi-layer separation tower top light removal pipeline (24) is connected to a recovery tank; a silane product storage tank refrigerant jacket (29) and a silane product storage tank heating device (30) are provided on the silane product storage tank (28); the silane product storage tank (28) is connected to a silane product storage tank analysis pipeline (32), and a silane product storage tank analysis valve (31) is provided on the silane product storage tank analysis pipeline (32); The bottom of the multilayer separation tower (23) is provided with a multilayer separation tower heating device (22) and a multilayer separation tower liquid level meter (51); the bottom of the multilayer separation tower (23) is also connected to a multilayer separation tower bottom deweighting pipeline (21); the multilayer separation tower bottom deweighting pipeline (21) is provided with a multilayer separation tower bottom deweighting pipeline regulating valve (20); the lower part of the multilayer separation tower (23) is connected to a disilane product storage tank (35) via a disilane collecting pipeline (34); the disilane collecting pipeline (34) is connected to a disilane product storage tank (35); A disilane collection flowmeter (44), a disilane collection regulating valve (33) and a disilane collection filter (47) are sequentially arranged on the line (34); a disilane product storage tank (35) is provided with a disilane product storage tank refrigerant jacket (36) and a disilane product storage tank heating device (37); the disilane product storage tank (35) is connected to a disilane product storage tank analysis pipeline (39); and a disilane product storage tank analysis valve (38) is arranged on the disilane product storage tank analysis pipeline (39); The multilayer adsorption tower (5) is provided with 4 layers of fillers, each layer of fillers has a height of 2-2.5 m; each layer of fillers is composed of four parts, namely silica gel, γ-alumina, carbon nanotubes and molecular sieves, wherein the silica gel particle size is 3-5 mm, the γ-alumina particle size is 2-4 mm, the carbon nanotube particle size is 2-3 mm, and the molecular sieve particle size is 1-2 mm.

7. A purification device for efficiently obtaining silane and disilane according to claim 6, characterized in that: The multilayer adsorption tower (5) has a working pressure of 0.2-1.5 MPa and a height of 8-10 m; the ratio of silica gel, γ-alumina, carbon nanotubes and molecular sieve in the adsorption tower is 3:1:2:2, and the four fillers are arranged regularly from bottom to top; The refrigerant in the storage tank refrigerant jacket (29) is one of liquid nitrogen and dichloromethane; the feed flow rate of the multi-layer separation tower (23) is 0~40kg / h, the height of the separation tower is 30~40m, the diameter of the separation tower column is 0.5~0.8m, the liquid level of the separation tower is 1500~2500mm, the pressure of the separation tower is 0.05~1.3Mpa, the temperature of the separation tower is -30~-100℃, and the heating power of the bottom of the separation tower is 40~50KW.

8. A purification device for efficiently obtaining silane and disilane according to claim 6, characterized in that: The inlet of the multilayer adsorption tower (5) to the separation tower pipeline (19) is located 15 to 20 m above the bottom of the multilayer separation tower (23), and there are three inlets on the same horizontal plane with an included angle of 120°; The top condenser of the multilayer separation tower (23) has a height of 2 to 3 m and a diameter of 0.5 to 1 m; the silane collection pipeline (27) at the top of the separation tower is located 1.5 to 2 m from the top of the tower, and the extraction flow rate is 0 to 18 kg / h; The bottom of the multilayer separation tower (23) has a height of 2-3 m and a diameter of 1-2 m. The disilane collecting pipeline (34) of the bottom of the separation tower is located 2.5-3 m from the bottom of the bottom, and the extraction flow rate is 0-18 kg / h. The silane collection filter (46) and the disilane collection filter (47) are both 2.5 nm high-precision filters, and the roughness of the inner wall of the filter is less than 0.2 μm; The multi-layer adsorption tower (5), the multi-layer separation tower (23), the regeneration gas storage tank (16), the silane product storage tank (28) and the disilane product storage tank (35) are made of one of 316L stainless steel and monel alloy, and the inner walls of all equipment must be electrochemically polished, with an inner wall roughness of less than 0.2 um; The filler in the multilayer separation tower (23) is one of the θ rings, ball rings, and Raschig rings, the diameter of the filler is 10-20 mm, and the material of the θ rings, ball rings, and Raschig rings is independently one of stainless steel, monel alloy, nickel, polytetrafluoroethylene, and alumina ceramics.

9. A purification device for efficiently obtaining silane and disilane according to claim 8, characterized in that: There are two multi-layer adsorption towers (5) and two regeneration gas storage tanks (16), one of which is used as a spare.

10. Use of a purification device for efficiently obtaining silane and disilane according to claim 9, characterized in that: It is suitable for the separation of two substances with a boiling point difference of 30°C or more, and is suitable for the separation of silane and disilane.

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