Preparation method and system of catalyst for preparing high-purity deuterated silane through disproportionation reaction

Abstract

The invention provides a preparation method and system of a catalyst for preparing high-purity deuterated silane through disproportionation reaction, and relates to the technical field of catalyst preparation. The invention relates to a preparation method of a catalyst for preparing high-purity deuterated silane through a disproportionation reaction. The preparation method comprises the following steps: (1) carrying out primary isotope exchange on a dehydrated weak base resin catalyst and heavy water with the purity lower than 99%; (2) performing secondary isotope exchange on the weak base resin catalyst prepared in the step (1) and heavy water with the purity not lower than 99%, and dehydrating to obtain a deuterated weak base resin catalyst; wherein the heavy water with the purity lower than 99% is a heavy water potassium carbonate solution, and the concentration of potassium carbonate in the heavy water potassium carbonate solution is 1-10 wt%; the weak base resin catalyst is weak base resin with a benzene ring and a tertiary amine group. The method has the advantages of high atom utilization rate of deuterium, high deuteration degree of the deuterated weak base resin catalyst, high catalyst preparation efficiency, simple and efficient process, and safe and reliable production process.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of catalyst preparation, in particular to a preparation method and system of a catalyst for preparing high-purity deuterated silane through disproportionation reaction. BACKGROUND

[0002] Deuterated chemicals are an important class of high-value-added chemicals. The abundance of deuterium in the earth's crust is much lower than that of ordinary hydrogen (protium), and the annual production scale of deuterated chemicals is usually at or below the ton level. Deuterated silane can not only be used as a probe for the study of organosilicon chemical mechanisms, but also can be used as a deuterated reagent and can transfer deuterium to organic compounds through mature silicon hydrogenation reactions. There are two methods for preparing deuterated silane at present: one is to reduce halosilane with LiAlD4 or NaBD4, the deuterated reducing agent is easy to decompose and unstable, and high-purity alkaline earth metals and aluminum powder are consumed, and the energy consumption is high, which is an abandoned process route in the industrial production of ordinary silane; the other is that the Si-H bond of silane exchanges isotopes under the catalysis of metal and D2, and the properties of various products with different exchange degrees of isotopes are close, so it is difficult to separate. The problems existing in the above preparation technologies affect the utilization rate of deuterium atoms and increase the cost of raw materials.

[0003] At present, the industrial production of ordinary silane adopts coupling of cold hydrogenation reaction and disproportionation reaction, and four chlorosilanes realize circulation while producing silane from metallurgical silicon and hydrogen gas (CN110963494A): Cold hydrogenation reaction:

[0004] Disproportionation reaction:

[0005] Combining the mature chlorosilane rectification purification technology and disproportionation reaction rectification technology, the atomic utilization rate and product purity of the production process of ordinary silane are very high. Since the atomic mass of deuterium is significantly different from that of protium, the reaction speed of deuterium is slower than that of ordinary hydrogen, and the conversion rate is also lower. Despite this, the above production process of ordinary silane can be used to produce deuterated silane after appropriate adjustment and optimization. However, the weak base resin catalyst used in the disproportionation reaction contains ordinary hydrogen (protium) atoms, and direct use in the production of deuterated silane will cause isotopic exchange, reducing the purity of deuterated silane, which is one of the key problems to be solved.

[0006] The preparation process of the weak base resin catalyst is complex, and the cost of directly synthesizing deuterated weak base resin catalyst is high. The C-H bond on the benzene ring has a very strong bond energy, greater than 110 kcal / mol, and the bond energy of the C-H bond on the methyl group is usually also around 100 kcal / mol. It is very difficult to directly use hydrogen / deuterium ion exchange to modify the weak base resin catalyst for deuterated silane. The existing deuterated resin is mainly prepared by isotopic exchange, and the concentration of heavy water is as high as 99% or more. The H + / OH - The method takes a long time to reach reaction equilibrium, consumes a large amount of heavy water, and has high cost. In addition, CN118718927A discloses a deuterium-substituted resin preparation system and method, which uses a DCl heavy water solution to convert a sodium-type cation resin into a D-type resin, and uses NaOD to convert a chlorine-type anion resin into an OD-type resin. Since the D + ion and OD - ion concentration is 5-8 orders of magnitude higher than that in the traditional heavy water preparation method, the reaction rate is high, and the preparation time is short. However, the method is only suitable for H + or OH - type resin.

[0007] Although there are currently many methods for deuterium substitution of organic matter, such as photocatalytic deuterium substitution reaction, metal-catalyzed deuterium substitution reaction, and chemical synthesis, the deuterium substitution system and reaction process are very complex, and the subsequent purification process is tedious, which is not suitable for the production of deuterium-substituted silane catalysts. Therefore, it is necessary to develop a process route for the industrial production of deuterium-substituted weak base resin catalysts with high deuterium atom utilization rate, simple and efficient process, safe and reliable production process, and application of high-purity deuterium-substituted silane, according to the specific reaction process characteristics and structural characteristics of the resin catalyst used. SUMMARY

[0008] The purpose of the present application is to provide a preparation method of a catalyst for preparing high-purity deuterium-substituted silane by disproportionation reaction, which uses a weak base resin catalyst used in high-purity silane production as a raw material, and uses a potassium carbonate solution of heavy water to prepare a deuterium-substituted weak base resin catalyst by isotope exchange. The method has high deuterium atom utilization rate, high deuterium substitution degree of the deuterium-substituted weak base resin catalyst, high catalyst preparation efficiency, simple and efficient process, and safe and reliable production process.

[0009] Another purpose of the present application is to provide a preparation system of a catalyst for preparing high-purity deuterium-substituted silane by disproportionation reaction, which is used to prepare the above-mentioned deuterium-substituted weak base resin catalyst to meet the production needs of high-purity deuterium-substituted silane on an industrial scale.

[0010] The present application is achieved by the following technical solutions: A preparation method of a catalyst for preparing high-purity deuterium-substituted silane by disproportionation reaction, comprising the following steps: (1) performing first isotope exchange on the dehydrated weak base resin catalyst and heavy water with a purity of less than 99%; (2) performing second isotope exchange on the weak base resin catalyst prepared in step (1) and heavy water with a purity of not less than 99%, and dehydrating to obtain a deuterium-substituted weak base resin catalyst; The heavy water with a purity less than 99% is a potassium carbonate solution of heavy water, and the concentration of potassium carbonate in the potassium carbonate solution of heavy water is 1-10 wt%.

[0011] Further, in (1), the reaction temperature is 80-100°C, and the reaction time is 10-30 min.

[0012] Further, in (2), the reaction temperature is 30-50°C, and the reaction time is 30-60 min.

[0013] Further, the dehydration of (1) and (2) is: drying and dehydration are carried out in a low-temperature inert atmosphere, the purity of the low-temperature inert atmosphere is not less than 99.999%, the temperature of the low-temperature inert atmosphere is 60-120°C, and the final water content in the low-temperature inert atmosphere is less than 1 ppm.

[0014] Further, in (2), the isotopically exchanged heavy water is recovered and treated by a rectifying column, wherein the theoretical plate number of the rectifying column is 200-350.

[0015] Further, the reflux ratio of the rectifying column is 30-300, and the high reflux ratio operation condition facilitates smooth start-up.

[0016] Further, the reboiling ratio of the bottom of the rectifying column is not less than 20.

[0017] A preparation system of a catalyst for preparing high-purity deuterated silane by disproportionation reaction, comprising a heat exchanger, a reactor and a distillation recovery system connected in sequence through a heavy water pipeline; wherein a circulation pipeline one is connected between the outlet of the reactor and the inlet of the heat exchanger, a production pipeline is connected to the top of the distillation recovery system, a heavy water recovery pipeline is connected to the bottom of the distillation recovery system, a heavy water supplement pipeline is connected to the inlet of the heat exchanger, the heavy water recovery pipeline is connected to the heavy water supplement pipeline, a liquid pump is arranged on the heavy water pipeline of the reactor outlet, and the outlet of the liquid pump is connected to the distillation recovery system and the circulation pipeline one, respectively.

[0018] Further, the distillation recovery system comprises one rectifying column, the outlet of the reactor is connected to the middle part of the rectifying column through a heavy water pipeline, the top of the rectifying column is connected to the production pipeline, and the bottom of the rectifying column is connected to the heavy water recovery pipeline.

[0019] Further, the rectification recovery system comprises rectification tower I and rectification tower II arranged in series, the outlet of the reactor is connected with the middle part of the rectification tower I through a heavy water pipeline, the bottom of the rectification tower I is connected with the upper part of the rectification tower II through a heavy water pipeline, the production pipeline is connected with the top of the rectification tower I, the heavy water recovery pipeline is connected with the bottom of the rectification tower II, and the circulation pipeline II is connected between the top of the rectification tower II and the bottom of the rectification tower I.

[0020] The technical scheme of the present application has at least the following advantages and beneficial effects: 1. Based on the market size of deuterated silane and the characteristics of isotope exchange, a deuterated weak base resin catalyst preparation method suitable for ton-level deuterated silane industrial production is designed and developed, which uses a weak base resin catalyst as a raw material and a heavy water potassium carbonate solution for isotope exchange, so that the overall process route is simple and efficient, the equipment investment is low, the energy consumption is low, and large-scale industrial production can be carried out.

[0021] 2. The catalyst used in the present application is a weak basic resin with a benzene ring and a tertiary amine group, wherein the tertiary amine group is a weak basic center, the bond energy of the C-H bond of the benzene ring and the tertiary amine group is large, and the deuterium exchange time can be effectively shortened by adding potassium carbonate in a low-concentration heavy water solution, thereby reducing the consumption of heavy water and the production cost of the catalyst.

[0022] 3. Theoretically, the hydrogen (protium) on the surface of the deuterated weak base resin catalyst can be completely exchanged, the deuterium exchange degree of the deuterated base resin catalyst is high, and the abundance of deuterated silane can be improved. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 The structure schematic diagram of the preparation system of the catalyst for preparing high-purity deuterated silane by disproportionation reaction provided for the embodiment 1 of the present application.

[0024] Figure 2 The structure schematic diagram of the preparation system of the catalyst for preparing high-purity deuterated silane by disproportionation reaction provided for the embodiment 2 of the present application.

[0025] Figure legend: 1-heat exchanger, 2-reactor, 3-rectification tower, 4-liquid pump, 5-circulation pipeline I, 6-production pipeline, 7-heavy water recovery pipeline, 8-heavy water supplement pipeline, 9-rectification tower I, 10-rectification tower II, 11-circulation pipeline II; Among them, S1-supplement heavy water, S2-heavy water stream after isotope exchange, S3-circulating heavy water stream after isotope exchange, S4-heavy water stream entering the heavy water rectification recovery system, S5-heavy water circulating stream after H2O removal, S6-heavy water stream entering the rectification tower II, S7-heavy water circulating stream entering the bottom of the rectification tower I. DETAILED DESCRIPTION

[0026] The application will be further described below in conjunction with the specific embodiments, but the embodiments do not limit the application in any form. Unless otherwise specified, the raw materials used in the embodiments of the application are commercially available raw materials.

[0027] Example 1 With reference to Figure 1 The present embodiment provides a preparation system of a catalyst for preparing high-purity deuterated silane by disproportionation reaction, comprising a heat exchanger 1, a reactor 2 and a distillation recovery system connected in sequence through a heavy water pipeline; wherein a circulation pipeline one 5 is connected between the outlet of the reactor 2 and the inlet of the heat exchanger 1, a production pipeline 6 is connected to the top of the distillation recovery system, and a heavy water recovery pipeline 7 is connected to the bottom of the distillation recovery system.

[0028] Based on the market size of deuterated silane and the characteristics of isotope exchange, a deuterated weak base resin catalyst preparation system suitable for ton-level industrial production of deuterated silane is designed and developed. The ordinary weak base resin catalyst is used as raw material, and the heavy water is used to modify it into deuterated weak base resin catalyst by isotope exchange in the reactor 2. The overall process route is simple and efficient, the equipment investment is low, the energy consumption is low, and large-scale industrial production can be carried out. The atomic utilization rate of deuterium in the system is high, the deuteration degree of the deuterated weak base resin catalyst is high, the hydrogen (protium) on the surface of the deuterated weak base resin catalyst can be completely exchanged in theory, the catalyst preparation efficiency is high, the abundance of deuterated silane is high, the preparation system is simple and efficient, the production process is safe and reliable, and it can meet the production demand of high-purity deuterated silane on an industrial scale.

[0029] As a preferred embodiment of the present embodiment, a liquid pump 4 is arranged on the heavy water pipeline at the outlet of the reactor 2, and the outlet of the liquid pump 4 is connected with the distillation recovery system and the circulation pipeline one 5 respectively.

[0030] As a preferred embodiment of the present embodiment, the inlet of the heat exchanger 1 is further connected with a heavy water supplement pipeline 8, and the heavy water recovery pipeline 7 is connected with the heavy water supplement pipeline 8.

[0031] Among them, the heavy water stream S1 enters the heat exchanger 1, is preheated to the required temperature by the heat exchanger 1, and then enters the reactor 2. The heavy water stream S2 after isotope exchange in the reactor 2 is transported by the liquid pump 4 to divide into two streams S3 and S4. The S3 stream returns to the heat exchanger 1 through the circulation pipeline one 5, and the S4 stream enters the distillation recovery system to separate water (H2O) in the heavy water. The recovered heavy water S5 returns to the heat exchanger 1 through the heavy water recovery pipeline 7.

[0032] When the heavy water used has a purity less than 99%, the reaction temperature is 60-120°C, and the average circulation residence time of the heavy water S1 in the isotope exchange reactor 2 is 10-30 min; when high-purity heavy water is used, the reaction temperature is gradually decreased from 60-120°C to 30-50°C, and the average circulation residence time of the heavy water S1 in the isotope exchange reactor 2 is 30-60 min.

[0033] The heavy water isotope exchange process can be continuous, i.e. the heavy water S1 is continuously fed into the isotope exchange reactor 2 and the heavy water S4 is continuously drained from the isotope exchange reactor 2, and the average circulation residence time of the heavy water in the reactor 2 is controlled by the flow rate of S1 or S4. The heavy water isotope exchange process can also be intermittent, i.e. the heavy water is fed into the isotope exchange reactor 2 through S1 and kept for a certain average circulation residence time, and then the water fed into the reactor 2 through S1 is drained through S4 and then re-fed.

[0034] As a preferred embodiment of the present embodiment, the rectification recovery system comprises one rectification column 3, the outlet of the reactor 2 is connected to the middle part of the rectification column 3 through a heavy water pipeline, the top of the rectification column 3 is connected to the production pipeline 6, and the bottom of the rectification column 3 is connected to the heavy water recovery pipeline 7. The rectification column 3 uses high-performance packing, and the theoretical plate number is 350.

[0035] A method for preparing a catalyst for preparing high-purity deuterated silane by disproportionation reaction, comprising the following steps: First, the weak base resin catalyst is loaded into the isotope exchange reactor 2, and then the heavy water potassium carbonate solution S1 is adjusted in temperature and fed into the isotope exchange reactor 2. After circulating for a certain time, the heavy water S4 is led out and fed into the middle part of the rectification column 3. The heavy water (containing a small amount of HDO) at the bottom of the rectification column 3 is adjusted in temperature and then returned to the isotope exchange reactor 2, and the water (containing a small amount of HDO) at the top of the rectification column 3 is produced; the operation is divided into two stages: (1) The early water separation stage: the heavy water potassium carbonate solution S1 is controlled in temperature at 80°C by the heat exchanger 1 and then fed into the isotope exchange reactor 2. The average circulation residence time of the heavy water potassium carbonate solution in the isotope exchange reactor 2 is 10 min. Part of the outlet S4 of the isotope exchange reactor 2 is fed into the lower part of the rectification column 3. The water (H2O) and a small amount of HDO produced by isotope exchange and remaining in the resin are separated out at the top of the rectification column 3, and deuterium atoms (heavy water potassium carbonate solution) are supplemented to the system. The reflux ratio is gradually increased from 30 to 300, and the HDO concentration in the top production stream is ensured to be not more than 1% (or the deuterium atoms are not more than 0.5% of the hydrogen elements). The reboiling ratio at the bottom is not less than 50, and the HDO concentration in the bottom recycled heavy water stream is ensured to be not more than 1%. (2) Later water diversion stage: more than 99% of heavy water S1 is controlled at 30℃ by heat exchanger 1, intermittently introduced into isotope exchange reactor 2 and circulated for 30 minutes, introduced into the middle of rectification column 3 through S4; rectification column 3 maintains high reflux ratio of 300 while the HDO concentration at the top of the column is more than 1%, and full reflux mode is used, and the mixed liquid of water and HDO at the top is intermittently collected, and deuterium atoms (heavy water D2O) are supplemented to the system; the reboiling ratio of the column bottom of rectification column 3 is increased to ensure that the heavy water D2O concentration of the column bottom stream S5 is not less than 99.99%; when the HDO concentration at the top of rectification column 3 is more than 10%, the top collection is stopped, and the heavy water introduced into the isotope exchange reactor 2 is gradually reduced to 45℃ by heat exchanger 1, and the system is maintained for 5 hours after the top collection is stopped.

[0036] Among them, the reversible disproportionation reaction of semi-heavy water HDO in rectification column 3 is as follows: , and is continuously generated and consumed. The concentration of potassium carbonate in the potassium carbonate solution of heavy water is 1wt%, and the weak base resin catalyst is a weak base resin with a benzene ring and a tertiary amine group.

[0037] The isotope-exchanged resin is dried under the premise of not destroying the spatial structure of the resin in a low-temperature inert atmosphere to remove water in the modified weak base resin catalyst and heavy water in the modified resin catalyst. The purity of the low-temperature inert atmosphere is not less than 99.999%, the temperature of the low-temperature inert atmosphere is 60℃, and the final water content in the low-temperature inert atmosphere is less than 1ppm.

[0038] Example 2 Referring to Figure 2 , the present embodiment provides a preparation system of a disproportionation reaction catalyst for preparing high-purity deuterated silane, and a rectification recovery system includes rectification column one 9 and rectification column two 10 arranged in series, the outlet of the reactor 2 is connected with the middle of the rectification column one 9 through a heavy water pipeline, the bottom of the rectification column one 9 is connected with the upper part of the rectification column two 10 through a heavy water pipeline, the collection pipeline 6 is connected with the top of the rectification column one 9, and the heavy water recovery pipeline 7 is connected with the bottom of the rectification column two 10.

[0039] As a preferred embodiment of the present embodiment, a circulation pipeline two 11 is connected between the top of the rectification column two 10 and the bottom of the rectification column one 9. Among them, the rectification column one 9 and the rectification column two 10 both use high-performance fillers, and the theoretical plate number is 200.

[0040] A preparation method of a disproportionation reaction catalyst for preparing high-purity deuterated silane includes the following steps: First, the weak base resin catalyst is loaded into the isotopic exchange reactor 2, and then the heavy water potassium carbonate solution S4 is continuously introduced into the lower part of the rectifying column 1, the low deuterium water H2O is taken out from the top of the rectifying column 1, and the liquid S6 is taken out from the bottom of the rectifying column 1 and introduced into the upper part of the rectifying column 2, the vapor stream S7 is introduced into the tower kettle of the rectifying column 1 as a (large) part of the reboiling heat source of the rectifying column 1; the heavy water S5 (containing a small amount of semi-heavy water HDO) at the bottom of the rectifying column 2 is continuously returned to the isotopic exchange reactor 2 after temperature adjustment; the operation is divided into two stages: (1) The early continuous water separation stage: the heavy water potassium carbonate solution is controlled at 90°C by the heat exchanger 1, enters the isotopic exchange reactor 2, and the heavy water circulates in the isotopic exchange reactor 2 for an average residence time of 20 minutes; part of the reactor 2 outlet S4 enters the lower part of the rectifying column 1, and the rectifying column 1 continuously separates the water (H2O) remaining in the resin and produced by isotopic exchange from the top, and supplements the deuterium atoms (heavy water potassium carbonate solution) to the system; the reflux ratio of the rectifying column 1 gradually increases from 30 to 200, ensuring that the top stream of the rectifying column 1 is low deuterium water (semi-heavy water HDO content is less than 1%); the heavy water and semi-heavy water at the bottom of the rectifying column 1 enter the top or upper part of the rectifying column 2, and the reboiling ratio at the bottom of the rectifying column 2 is not less than 20, ensuring that the bottom stream S5 of the rectifying column 2 is heavy water D2O with a concentration of not less than 99% (containing a small amount of semi-heavy water HDO); (2) The later intermittent water separation stage: more than 99% of the heavy water S1 is controlled at 40°C by the heat exchanger 1, intermittently introduced into the isotopic exchange reactor 2 and circulated for 50 minutes, introduced into the lower part of the rectifying column 1 through S4, and the rectifying column 1 maintains a high reflux ratio of 200, but the top cannot take out low deuterium water (semi-heavy water HDO content exceeds 1%), and the full reflux mode is used, and the top intermittently takes out the mixed liquid of water and HDO, and supplements the deuterium atoms (heavy water D2O) to the system; the average residence time of the heavy water in the isotopic exchange reactor 2 is 40 minutes; the HDO concentration at the top of the rectifying column 1 gradually rises to more than 10% (or one-fourth of the deuterium atoms of the hydrogen element), and the top is stopped, and at the same time, the reboiling ratio of the kettle of the rectifying column 2 is increased, ensuring that the bottom stream S5 of the rectifying column 2 is heavy water D2O with a concentration of not less than 99.99%; the heavy water entering the isotopic exchange reactor 2 is gradually reduced to 40°C by the heat exchanger 1, and the top is stopped after 3 hours of system operation.

[0041] Among them, the semi-heavy water HDO undergoes the following disproportionation reaction during the circulation in the rectifying column 1 and the rectifying column 2: , and is continuously generated and consumed. The concentration of potassium carbonate in the heavy water potassium carbonate solution is 6wt%, and the weak base resin catalyst is a weak base resin with a benzene ring and a tertiary amine group.

[0042] The isotopically exchanged resin is dried under low-temperature inert atmosphere without destroying the spatial structure of the resin to remove the moisture in the weak base resin catalyst before modification and the heavy water in the modified resin catalyst. The purity of the low-temperature inert atmosphere is not less than 99.999%, the temperature of the low-temperature inert atmosphere is 100°C, and the final water content in the low-temperature inert atmosphere is less than 1 ppm.

[0043] Example 3 A method for preparing a catalyst for preparing high-purity deuterated silane by disproportionation reaction, using the preparation system of Example 2, comprising the following steps: First, the weak base resin catalyst is loaded into the isotopic exchange reactor 2, and then the heavy water potassium carbonate solution S4 is continuously fed into the lower part of the rectifying column 1, the low-deuterium water H2O is collected at the top of the rectifying column 1, the liquid S6 is collected at the bottom of the rectifying column 1 and fed into the upper part of the rectifying column 2, the vapor stream S7 at the top of the rectifying column 2 is fed into the column still of the rectifying column 1 as a (large) part of the reboiling heat source of the rectifying column 1; the heavy water S5 (containing a small amount of semi-heavy water HDO) at the bottom of the rectifying column 2 is continuously returned to the isotopic exchange reactor 2 after temperature adjustment; the operation is divided into two stages: (1) The early continuous water removal stage: the heavy water potassium carbonate solution is controlled at a temperature of 100°C by the heat exchanger 1, enters the isotopic exchange reactor 2, and the heavy water has an average circulation residence time of 30 minutes in the isotopic exchange reactor 2; part of S4 at the outlet of the reactor 2 enters the lower part of the rectifying column 1, and the water (H2O) remaining in the resin and generated by isotopic exchange is continuously separated at the top of the rectifying column 1 and deuterium atoms are supplemented to the system (heavy water potassium carbonate solution); the reflux ratio of the rectifying column 1 is gradually increased from 30 to 200, ensuring that the top stream of the rectifying column 1 is low-deuterium water (semi-heavy water HDO content is less than 1%); the heavy water and semi-heavy water at the bottom of the rectifying column 1 enter the top or upper part of the rectifying column 2, and the reboiling ratio at the bottom of the rectifying column 2 is not less than 20, ensuring that the bottom stream S5 of the rectifying column 2 is heavy water D2O with a concentration of not less than 99% (containing a small amount of semi-heavy water HDO); The semi-heavy water HDO undergoes the following disproportionation reaction during the circulation in the rectifying column 1 and the rectifying column 2: and is continuously generated and consumed; (2) After the intermittent water phase: more than 99% of the heavy water S1 is controlled by the heat exchanger 1 at 50℃, intermittently introduced into the isotope exchange reactor 2 and circulated for 60 minutes, introduced into the lower part of the rectifying column 9 through S4, and the rectifying column 9 is kept at a high reflux ratio of 200, and the low deuterium water (the half heavy water HDO content exceeds 1%) cannot be taken out from the top of the column. Instead, the full reflux mode is used, and the mixed liquid of water and HDO is intermittently taken out from the top of the column, and deuterium atoms (heavy water D2O) are supplemented to the system; the average circulation residence time of heavy water in the isotope exchange reactor 2 is 40 minutes; the HDO concentration at the top of the rectifying column 9 gradually increases to more than 10% (or deuterium atoms account for one fourth of hydrogen elements), and the top of the column is stopped, and at the same time, the reboiling ratio of the column bottom of the rectifying column 2 10 is increased to ensure that the heavy water D2O concentration of the column bottom stream S5 is not less than 99.99%; the heavy water introduced into the isotope exchange reactor 2 is gradually reduced to 40℃ by the heat exchanger 1, and the system is maintained for 3 hours after the top of the column is stopped.

[0044] In the circulation process of the half heavy water HDO in the rectifying column 9 and the rectifying column 2 10, the disproportionation reaction of the half heavy water HDO occurs as follows: , and is continuously generated and consumed. The concentration of potassium carbonate in the potassium carbonate solution of heavy water is 10wt%, and the weak base resin catalyst is a weak base resin with a benzene ring and a tertiary amine group.

[0045] The isotope-exchanged resin is dried under the premise of not destroying the spatial structure of the resin in a low-temperature inert atmosphere to remove water in the weak base resin catalyst before modification and heavy water in the modified resin catalyst. The purity of the low-temperature inert atmosphere is not less than 99.999%, the temperature of the low-temperature inert atmosphere is 120℃, and the final water content in the low-temperature inert atmosphere is less than 1ppm.

[0046] Comparative Example 1 In this comparative example, the heavy water with a purity of not less than 99% is used for isotope exchange with the weak base resin catalyst in the early and late stages. The rest is the same as Example 1.

[0047] Comparative Example 2 In this comparative example, the potassium carbonate solution of heavy water is used for isotope exchange with the weak base resin catalyst in the early and late stages. The rest is the same as Example 1.

[0048] Comparative Example 3 In this comparative example, the concentration of potassium carbonate in the potassium carbonate solution of heavy water is 15wt%. The rest is the same as Example 1.

[0049] Comparative Example 4 In this comparative example, the concentration of potassium carbonate in the potassium carbonate solution of heavy water is 0.5wt%. The rest is the same as Example 1.

[0050] Comparative Example 5 In the present comparative example, the potassium carbonate in the potassium carbonate solution of heavy water is replaced by sodium carbonate, and the rest is the same as example 1.

[0051] The catalysts for preparing high-purity deuterated silane are prepared by the method of the examples and the comparative examples, and the same deuterium degree of the catalysts of the examples and the comparative examples is taken as the standard. Among them, the catalyst prepared by examples 1-3 takes about 96 hours to reach the standard, while the catalyst prepared by comparative example 1 takes 168 hours, the catalyst prepared by comparative example 2 takes 130 hours, the catalyst prepared by comparative example 3 takes 137 hours, the catalyst prepared by comparative example 4 takes 155 hours, and the catalyst prepared by comparative example 5 takes 125 hours.

[0052] In summary, the present application first uses the potassium carbonate solution of heavy water, and then uses the heavy water with a purity of not less than 99% and a weak base resin catalyst to carry out isotope exchange, which can shorten the deuterium time, reduce the consumption of heavy water, and reduce the production cost of the catalyst.

[0053] The above only is the preferred embodiment of the present application, and is not used to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for preparing a catalyst for the disproportionation reaction to prepare high-purity deuterated silanes, characterized in that, Includes the following steps: (1) The dehydrated weak base resin catalyst was subjected to a first isotope exchange with heavy water with a purity of less than 99%. (2) The weak base resin catalyst obtained in step (1) is subjected to a second isotope exchange with heavy water with a purity of not less than 99% to dehydrate and obtain a deuterated weak base resin catalyst. Among them, the heavy water with a purity of less than 99% is a potassium carbonate solution of heavy water, and the concentration of potassium carbonate in the potassium carbonate solution of heavy water is 1-10 wt%; the weak base resin catalyst is a weak base resin with benzene rings and tertiary amine groups.

2. The method for preparing the catalyst for the disproportionation reaction to prepare high-purity deuterated silanes according to claim 1, characterized in that, (1) The reaction temperature is 80-100℃ and the reaction time is 10-30min.

3. The method for preparing the catalyst for the disproportionation reaction to prepare high-purity deuterated silanes according to claim 1, characterized in that, (2) The reaction temperature is 30-50℃ and the reaction time is 30-60min.

4. The method for preparing the catalyst for the disproportionation reaction to prepare high-purity deuterated silanes according to claim 1, characterized in that, The dehydration of (1) and (2) is carried out by using a low-temperature inert atmosphere for drying and dehydration. The purity of the low-temperature inert atmosphere is not less than 99.999%, the temperature of the low-temperature inert atmosphere is 60-120℃, and the final water content in the low-temperature inert atmosphere is less than 1ppm.

5. The method for preparing the catalyst for the disproportionation reaction to prepare high-purity deuterated silanes according to claim 1, characterized in that, (2) also includes the recovery of heavy water after isotope exchange through a distillation column, wherein the theoretical plate number of the distillation column is 200-350.

6. The method for preparing the catalyst for the disproportionation reaction to prepare high-purity deuterated silanes according to claim 5, characterized in that, The reflux ratio of the distillation column is 30-300.

7. The method for preparing the catalyst for the disproportionation reaction to prepare high-purity deuterated silanes according to claim 5, characterized in that, The reboiling ratio at the bottom of the distillation column shall not be less than 20.

8. A preparation system for a method of preparing a catalyst for preparing high-purity deuterated silanes based on the disproportionation reaction according to any one of claims 1-7, characterized in that, The system includes a heat exchanger, a reactor, and a distillation recovery system connected in sequence via a heavy water pipeline. A circulation pipeline connects the outlet of the reactor to the inlet of the heat exchanger. A collection pipeline connects to the top of the distillation recovery system, and a heavy water recovery pipeline connects to the bottom of the system. A heavy water replenishment pipeline connects to the inlet of the heat exchanger, and the heavy water recovery pipeline is connected to the heavy water replenishment pipeline. A liquid pump is installed on the heavy water pipeline at the reactor outlet, and the outlet of the liquid pump is connected to both the distillation recovery system and the circulation pipeline.

9. The preparation system for the catalyst for the disproportionation reaction to prepare high-purity deuterated silanes according to claim 8, characterized in that, The distillation recovery system includes a distillation column. The outlet of the reactor is connected to the middle of the distillation column via a heavy water pipeline. The top of the distillation column is connected to the collection pipeline, and the bottom of the distillation column is connected to the heavy water recovery pipeline.

10. The preparation system for the catalyst for the disproportionation reaction to prepare high-purity deuterated silanes according to claim 8, characterized in that, The distillation recovery system includes a first distillation column and a second distillation column arranged in series. The outlet of the reactor is connected to the middle of the first distillation column via a heavy water pipeline. The bottom of the first distillation column is connected to the upper part of the second distillation column via a heavy water pipeline. The collection pipeline is connected to the top of the first distillation column. The heavy water recovery pipeline is connected to the bottom of the second distillation column. A second circulation pipeline is connected between the top of the second distillation column and the bottom of the first distillation column.

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