A system and method for the continuous production of chloropropyl triethoxysilane in a two-column esterification

Abstract

The application belongs to the technical field of chemical synthesis, and particularly relates to a system and method for producing chloropropyl triethoxysilane through double-tower continuous esterification, which comprises a falling film reactor, a reaction tower, a stripping tower, an anhydrous ethanol storage tank and a chloropropyl trichlorosilane storage tank, a first receiving kettle is arranged at the bottom of the reaction tower, and a second receiving kettle is arranged at the bottom of the stripping tower; the anhydrous ethanol storage tank is sequentially connected with a gasifier, the stripping tower, a condenser A and the falling film reactor, the chloropropyl trichlorosilane storage tank is connected with the falling film reactor; the falling film reactor is sequentially connected with the reaction tower, the first receiving kettle and the stripping tower, the stripping tower is connected with the reaction tower, and the second receiving kettle is connected with a post-processing device. The application does not need high temperature and high pressure, and does not need a neutralizing agent, and has the advantages of low energy consumption, high product purity, high yield, short reaction period, easy operation and low production cost.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of chemical synthesis, and particularly relates to a system and method for producing chloropropyl triethoxysilane through continuous esterification of a double column. BACKGROUND

[0002] The traditional synthesis route of chloropropyl triethoxysilane is that chloropropyl trichlorosilane and ethanol are subjected to esterification at 80-100 DEG C and 0.03 MPa. The reaction formula is as follows:

[0003] ClCH2CH2CH2SiCl3+CH3CH2OH→ClCH2CH2CH2Si(OCH2CH3)3+HCl.

[0004] In the traditional process, ethanol is added in batches, the reaction time is about 6 hours, the reaction is refluxed at 0.03 MPa for about 3 hours, the total reaction time is about 10 hours or more, and finally the crude product is neutralized by a neutralizing agent sodium ethoxide and then punched into a rectification column for refining to obtain chloropropyl triethoxysilane. The main disadvantage of the traditional process is that the esterification reaction is carried out under the process conditions of high temperature and high vacuum degree, which inevitably causes problems such as long reaction period, high energy consumption, and high content of hydrogen chloride in the initial product. Meanwhile, the production cost is greatly increased due to the relatively high price of the neutralizing agent. Moreover, the traditional single-column reaction is not easy to control, the temperature control requirement is more stringent, the reaction condition is relatively harsh, the product obtained by the reaction cannot reach the product quality of the double-column reaction, and a more complex rectification process is required, which has the problems of difficult operation, long period, complicated process, and high cost. SUMMARY

[0005] In view of the existing technical problems, the application provides a system and method for producing chloropropyl triethoxysilane through continuous esterification of a double column, which adopts a continuous reaction system, continuous feeding, and continuous product output, is energy-saving and efficient, does not need high temperature and high pressure, does not need a neutralizing agent, and has the advantages of low energy consumption, high product purity, high yield, short reaction period, easy operation, and low production cost.

[0006] The technical scheme of the application is as follows:

[0007] The system for producing chloropropyl triethoxysilane through continuous esterification of a double column comprises a falling film reactor, a reaction column, a stripping column, an anhydrous ethanol storage tank, and a chloropropyl trichlorosilane storage tank, the bottom of the reaction column is provided with a first receiving kettle, and the bottom of the stripping column is provided with a second receiving kettle; the anhydrous ethanol storage tank is sequentially connected with a gasifier, the stripping column, a condenser A, and the falling film reactor, the chloropropyl trichlorosilane storage tank is connected with the falling film reactor; the falling film reactor is sequentially connected with the top of the reaction column, the first receiving kettle, and the stripping column, the top of the stripping column is connected with the bottom of the reaction column; and the second receiving kettle is connected with a post-processing device.

[0008] Preferably, a pump is arranged between the anhydrous ethanol storage tank and the vaporizer, between the chloropropyl trichlorosilane storage tank and the falling film reactor, between the first receiving tank and the stripping column, and between the reflux tank and the falling film reactor.

[0009] Preferably, the first receiving tank is connected to the reflux column, and the reflux column is connected to the bottom of the reaction column. Flow regulating valves are arranged on the pipelines connecting the first receiving tank to the reflux column and the stripping column, respectively. The flow of the reaction liquid in the two routes can be conveniently controlled by the flow regulating valves.

[0010] Preferably, flow regulating valves are arranged on the pipelines connecting the condenser A connected to the stripping column and the reaction column, respectively. The proportion of the ethanol gas in the two routes can be adjusted by the flow regulating valves.

[0011] Preferably, a reflux tank is further arranged between the condenser A and the falling film reactor. The reflux tank can temporarily store the condensed ethanol.

[0012] Further preferably, the post-processing device comprises a falling film evaporator, and the second receiving tank is sequentially connected to the falling film evaporator and a temporary storage tank. The top of the falling film evaporator is sequentially connected to a condenser C and a receiving tank, and the receiving tank is connected to the reflux tank. A pump is arranged between the receiving tank and the reflux tank. The post-processing device effectively purifies the product and recovers ethanol. The recovered ethanol is sent to the reflux tank and then to the falling film reactor, completing the first step of the reaction and avoiding waste and pollution of ethanol and reducing costs.

[0013] Preferably, the top of the reaction column is sequentially connected to a column top condenser B, a falling film reactor, and a gas-liquid separator. The gas-liquid separator is connected to a hydrochloric acid absorption unit and the reaction column. In the reaction process of the reaction column, HCL (containing ethanol) gas is generated. The gas is condensed and enters the falling film reactor. The condensed ethanol continues to participate in the reaction. The HCL enters the gas-liquid separator, and the HCL generated in the falling film reactor also enters the gas-liquid separator. After passing through the gas-liquid separator, the HCL enters the hydrochloric acid recovery unit, and the ethanol is sent to the reaction column. The HCL is effectively recovered, and waste and pollution of ethanol are avoided.

[0014] A method for producing chloropropyl triethoxysilane by connecting two columns, which utilizes the above-mentioned system for producing chloropropyl triethoxysilane. The specific method is as follows:

[0015] (1) First, anhydrous ethanol gas is vaporized and introduced into the stripping column. After exiting the stripping column, part of the ethanol gas is condensed and introduced into the falling film reactor. Chloropropyl trichlorosilane is then introduced into the falling film reactor. Liquid ethanol and chloropropyl trichlorosilane undergo a preliminary reaction to generate a semi-finished product, which is introduced into the reaction column. The other part of the ethanol gas is introduced into the reaction column.

[0016] (2) in the reaction tower, the ethanol gas and the semi-product continue to carry out esterification reaction to obtain reaction liquid, the reaction liquid falls into the first receiving kettle, and then the reaction liquid is sent to the top of the stripping tower;

[0017] (3) the reaction liquid entering the stripping tower fully reacts with the ethanol gas, and then the liquid falls into the second receiving kettle, and then after treatment, chloropropyl triethoxysilane and ethanol are obtained.

[0018] Preferably, in step (1), one part of the ethanol gas is 1 / 3 of the ethanol gas, and the other part of the ethanol gas is 2 / 3 of the ethanol gas; in step (2), the liquid level in the first receiving kettle is 50-70%; and the molar ratio of chloropropyl trichlorosilane to anhydrous ethanol is 1:0.66-0.67. Controlling the ratio of raw materials ensures the best reaction effect, and the amount of ethanol used in the system and method of the application is less than that in the traditional method; the ethanol gas is divided into two parts, one part is cooled first and then introduced into the falling film reactor to complete the first step of the reaction, and the other part is introduced into the reaction tower to provide a heat environment for the reaction occurring in the reaction tower and simultaneously serve as the raw material for the reaction occurring in the reaction tower; the ethanol introduced into the stripping tower can ensure that the substances not fully reacted in the reaction tower are fully reacted, and the alcohol washing of the reaction product can also remove the chloride ions. Through ingenious design, the amount of ethanol required to complete the first step is met, the amount of ethanol required for the reaction in the reaction tower is met, and the amount of ethanol introduced can also ensure the temperature required for the reaction in the reaction tower, avoiding additional heating sources and enabling the entire process to be fully reacted, achieving multiple goals at once; and by controlling the liquid level in the first receiving kettle, the balance between feeding and discharging is effectively maintained.

[0019] Further preferably, in order to maintain the stability of the liquid level in the first receiving kettle, most of the reaction liquid in the first receiving kettle is sent to the stripping tower, and a small part of the reaction liquid is returned to the reaction tower, and the amount of the reaction liquid returned to the reaction tower is controlled according to the actual liquid level in the first receiving kettle.

[0020] Preferably, the gasification temperature of the anhydrous ethanol is 115-135℃; the bottom temperature of the stripping tower is controlled at 110-135℃, and the top temperature reaches 70-100℃; and the top temperature of the reaction tower is 30-90℃. The gasification temperature of the anhydrous ethanol ensures the gasification of the ethanol, and according to the temperature of the ethanol gas, a heat environment can be provided for the entire reaction, reducing the provision of external heat sources and energy consumption. If the top temperature of the reaction tower is too low, it indicates that the amount of ethanol is too small, causing insufficient reaction; and if the top temperature of the reaction tower is too high, it indicates that the amount of ethanol is too large, which is easy to cause high boiling and cause side reactions to occur; and the control of the temperature of the stripping tower effectively ensures that the reaction not fully reacted in the reaction tower can be completed in the stripping tower, and the stripping tower can also alcohol wash the reaction liquid produced by the reaction of the reaction tower, effectively reducing the chloride ion content, and the chloride ion content in the reaction liquid is less than 5PPM.

[0021] Preferably, the flow of chloropropyl triethoxysilane into the falling film reactor is controlled at 500-650 kg / h.

[0022] The anhydrous ethanol of the present application is vaporized and enters the stripping tower. One third of the ethanol from the stripping tower is condensed and then refluxed into the falling film reactor to react with chloropropyl trichlorosilane at room temperature to remove the first chlorine ion from the chloropropyl trichlorosilane. This is the principle of the reaction for producing chloropropyl triethoxysilane, which is determined by the inventors based on the characteristics of the reaction. The reaction at room temperature can complete the reaction and save energy. In the prior art, the process for producing chloropropyl triethoxysilane uses high temperature and high pressure from the start of the reaction to the end, which wastes energy and easily produces side reactions, and prolongs the reaction time. However, the present application effectively overcomes the defects of the prior art, reduces the production cost, and shortens the reaction time. Two thirds of the ethanol gas from the stripping tower enters the bottom of the reaction tower to heat the reaction tower. The reaction tower does not need to be heated by other means. The semi-finished product of the anhydrous ethanol and the chloropropyl trichlorosilane in the falling film reactor is sent to the reaction tower to react with the two thirds of the ethanol. The ethanol gas entering the reaction tower provides heat for the reaction tower and also serves as a reaction raw material. The reaction tower does not need other heating methods to provide heat. This further effectively saves energy. At this time, during the reaction in the reaction tower, HCL (containing ethanol) gas is generated. The gas is condensed and enters the falling film reactor. The condensed ethanol continues to participate in the reaction. The HCL enters the gas-liquid separator. The HCL generated in the falling film reactor also enters the gas-liquid separator. After passing through the gas-liquid separator, the HCL enters the hydrochloric acid recovery unit, and the ethanol is sent to the reaction tower. The HCL is effectively recovered, and the waste and pollution of ethanol are avoided. After the reaction in the reaction tower, the reaction liquid falls into the first receiving kettle. To control the stability of the liquid level and maintain the balance of the feed and discharge, a small part of the reaction liquid is refluxed to the reaction tower through the reflux tower to maintain the balance. Most of the reaction liquid is sent to the stripping tower. In the stripping tower, the unreacted substances in the reaction liquid react with the vaporized ethanol rising in the tower, and the ethanol flow is adjusted at any time to control the temperature at the top of the tower at 70-100°C. At the same time, the reaction liquid is washed with alcohol, which effectively reduces the content of chlorine ions. The liquid that has completely reacted falls into the second receiving kettle at the bottom of the tower. At this time, the main content of the liquid can reach more than 98.5%. The reacted liquid is directly transported to the falling film evaporator, and the substances with a relatively low boiling point (mostly excess ethanol) are evaporated into the receiving tank. The receiving tank refluxes the ethanol to the reflux tank to complete the reflux utilization of the ethanol. The product falls into the temporary storage tank. At this time, the main content of the product can reach more than 99.5%. This realizes the purification of the product and the recovery of the ethanol.

[0023] The present application uses ethanol gas as heat source and reaction raw material, saves energy consumption, meets the amount of ethanol required by the reaction, and meets the requirement of reaction temperature, in the reaction process, the raw material is first reacted with liquid ethanol, and then reacted with gaseous ethanol, so that each step can effectively react, the reaction rate is improved, the amount of ethanol is saved, and the energy consumption is saved. The present application is the first of its kind, which effectively saves energy consumption, improves reaction rate, avoids the occurrence of side reactions, effectively ensures instantaneous reaction, effectively recovers HCL and ethanol, and utilizes ethanol in the reaction to avoid resource waste and pollution, and reduce cost. The present application uses continuous feeding and discharging to realize continuous and instantaneous reaction, recycles and utilizes excess ethanol, recycles HCL in production, avoids pollution, and has the advantages of short reaction period, easy operation, low production cost, low energy consumption, high product purity, main content of 99.5% or more, yield of 99.5% or more, chloride ion of 5PPM or less. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 It is a structural schematic diagram of the system of the present application.

[0025] Among them, kettle A is the first receiving kettle, and kettle B is the second receiving kettle. DETAILED DESCRIPTION

[0026] In order to further understand the present application, the preferred embodiments of the present application are described below in conjunction with examples, but it should be understood that these descriptions are only for further illustrating the features and advantages of the present application, and are not limitations of the claims of the present application.

[0027] As shown in the figure, a system for producing chloropropyl triethoxysilane by double-tower continuous esterification includes a falling film reactor, a reaction tower, a stripping tower, an anhydrous ethanol storage tank, and a chloropropyl trichlorosilane storage tank. The bottom of the reaction tower is connected to the first receiving kettle, and the bottom of the stripping tower is connected to the second receiving kettle. The anhydrous ethanol storage tank is sequentially connected to the gasifier, the bottom of the stripping tower, the condenser A, and the upper part of the falling film reactor. The chloropropyl trichlorosilane storage tank is connected to the top of the falling film reactor. The bottom of the falling film reactor is sequentially connected to the top of the reaction tower, the first receiving kettle, and the upper part of the stripping tower. The top of the stripping tower is connected to the bottom of the reaction tower. The second receiving kettle is connected to the post-processing device. Pumps are arranged between the anhydrous ethanol storage tank and the gasifier, between the chloropropyl trichlorosilane storage tank and the falling film reactor, between the first receiving kettle and the reflux tower and the stripping tower, and between the reflux tank and the falling film reactor.

[0028] In another embodiment, the first receiving kettle is connected to the reflux tower, the reflux tower is connected to the bottom of the reaction tower, and flow regulating valves are arranged on the pipelines connecting the first receiving kettle to the reflux tower and the stripping tower, respectively. The reaction liquid in the first receiving kettle has two routes, one of which is sent into the stripping tower, and the other of which is sent into the reaction tower. The route into the reaction tower is designed to control the liquid level in the first receiving kettle, and to ensure the balance between the feed and the discharge. The flow of the reaction liquid in the two routes can be conveniently controlled by the flow regulating valves.

[0029] In another embodiment, flow regulating valves are arranged on the pipelines connecting the stripping tower to the condenser A and the reaction tower, respectively. The two routes at the top of the stripping tower ensure that the ethanol gas performs different functions and reactions. The flow regulating valves can adjust the proportional distribution of the ethanol gas in the two routes.

[0030] In another embodiment, a reflux tank is further arranged between the condenser A and the falling film reactor, the post-processing device comprises a falling film evaporator, and the second receiving kettle is sequentially connected to the falling film evaporator and the temporary storage tank. The top of the falling film evaporator is sequentially connected to the condenser C and the receiving tank, the receiving tank is connected to the reflux tank, and a pump is arranged between the receiving tank and the reflux tank. The post-processing device effectively purifies the product and recovers ethanol. The recovered ethanol is sent into the reflux tank and then flows into the falling film reactor to complete the first step of the reaction, thereby avoiding waste and pollution of ethanol and reducing costs.

[0031] In another embodiment, the top of the reaction tower is sequentially connected to the tower top condenser B, the falling film reactor, and the gas-liquid separator, and the gas-liquid separator is connected to the hydrochloric acid absorption unit and the reaction tower, respectively. In the reaction process in the reaction tower, HCL (containing ethanol) gas is generated. The gas is condensed and enters the falling film reactor. The ethanol after condensation continues to participate in the reaction. The HCL enters the gas-liquid separator, and the HCL generated in the falling film reactor also enters the gas-liquid separator. After passing through the gas-liquid separator, the HCL enters the hydrochloric acid recovery unit, and the ethanol is sent into the reaction tower. The HCL is effectively recovered, and waste and pollution of ethanol are avoided.

[0032] In another embodiment, the upper end of the reaction tower is slightly negative, and the lower end is slightly positive.

[0033] Based on the above-mentioned system for producing chloropropyl triethoxysilane by double-tower continuous esterification, a method for producing chloropropyl triethoxysilane by double-tower esterification is provided, and the specific method is as follows:

[0034] (1) First, anhydrous ethanol is gasified and introduced into the stripping tower. After exiting the stripping tower, part of the ethanol gas is condensed and introduced into the falling film reactor. Chloropropyl trichlorosilane is introduced into the falling film reactor. Liquid ethanol and chloropropyl trichlorosilane undergo preliminary reaction to generate a semi-finished product, which is introduced into the reaction tower. The other part of the ethanol gas is introduced into the reaction tower.

[0035] (2) The ethanol gas and the semi-product in the reaction tower are reacted to obtain a reaction liquid, which falls into the first receiving tank, and then the reaction liquid is sent to the top of the stripping tower;

[0036] (3) The reaction liquid in the stripping tower is fully reacted with the ethanol gas, and then the liquid falls into the second receiving tank, and then the chloropropyl triethoxysilane and ethanol are obtained after post-processing.

[0037] In step (1), one part of the ethanol gas is 1 / 3 ethanol gas, and the other part of the ethanol gas is 2 / 3 ethanol gas; in step (2), the liquid level in the first receiving tank is 50-70% (50-70% of the total liquid level of the first receiving tank); the molar ratio of chloropropyl trichlorosilane to anhydrous ethanol is 1:0.66-0.67. By controlling the ratio of raw materials, the best reaction effect is ensured, the ethanol gas is divided into two specific parts, one part is cooled and then introduced into the falling film reactor to complete the first step of the reaction, and the other part is introduced into the reaction tower to provide a heat environment for the reaction occurring in the reaction tower, and at the same time as the raw material for the reaction occurring in the reaction tower. Through ingenious design, the amount of ethanol required for the first step can be met, and the amount of ethanol required for the reaction in the reaction tower can also be met. The amount of ethanol introduced can also ensure the temperature required for the reaction in the reaction tower, avoiding additional heating, achieving multiple purposes at once; at the same time, by controlling the liquid level of the first receiving tank, the balance between feeding and discharging is effectively maintained.

[0038] In order to maintain the stability of the liquid level in the first receiving tank, most of the reaction liquid in the first receiving tank is sent to the stripping tower, and a small part is returned to the reaction tower. The amount of reflux into the reaction tower is controlled by the actual liquid level in the first receiving tank.

[0039] The gasification temperature of anhydrous ethanol is selected to be 115-135℃; the bottom temperature of the stripping tower is controlled to be 110-135℃, and the top temperature reaches 70-100℃; the top temperature of the reaction tower is 30-90℃, and the gasification temperature of anhydrous ethanol is ensured. At the same time, according to the temperature of the ethanol gas, a heat environment can be provided for the entire reaction, reducing the provision of external heat sources and energy consumption. If the temperature of the top of the reaction tower is too low, it indicates that the amount of ethanol is too small, causing insufficient reaction. If the temperature is too high, it indicates that the amount of ethanol is too much, which can easily cause high boiling and cause side reactions to occur. The control of the temperature of the stripping tower effectively ensures that the reaction can continue to be completed in the stripping tower when the reaction is not complete in the reaction tower. At the same time, the stripping tower can also perform alcohol washing on the reaction liquid produced by the reaction of the reaction tower, effectively reducing the chlorine ion content. The flow rate of chloropropyl triethoxysilane entering the falling film reactor is controlled to be 500-650kg / h; the temperature of the falling film evaporator in post-processing is 115-130℃, and the temporary storage tank in post-processing is under negative pressure.

[0040] The product obtained by the above method has a content of more than 98.5% before post-treatment, a main content of more than 99.5% after post-treatment, a yield of more than 99.5%, and a chloride ion content of less than 5 PPM.

[0041] The anhydrous ethanol of the present application is vaporized and enters the bottom of the stripping tower, and the ethanol gas from the top of the stripping tower is condensed and returned to the falling film reactor to react with chloropropyltrichlorosilane at room temperature to remove the first chloride ion of chloropropyltrichlorosilane. This is the principle of the reaction for producing chloropropyltriethoxysilane, and the inventors finally determined the room temperature reaction, which can not only complete the reaction, but also save energy. In the prior art, the process for producing chloropropyltriethoxysilane uses high temperature and high pressure from the beginning to the end, which not only wastes energy, but also easily produces side reactions and prolongs the reaction time. However, the present application effectively overcomes the defects of the prior art, reduces the production cost, and shortens the reaction time. The 2 / 3 ethanol gas from the stripping tower enters the bottom of the reaction tower to heat the reaction tower, and the reaction tower does not need to be heated by other means. The semi-finished product of anhydrous ethanol and chloropropyltrichlorosilane in the falling film reactor is sent to the reaction tower to react with the 2 / 3 ethanol. The ethanol gas entering the reaction tower not only provides heat for the reaction tower, but also serves as a reaction raw material. The reaction tower also does not need other heating methods to provide heat for it, which further effectively saves energy. At this time, HCL (containing ethanol) gas is generated in the reaction process in the reaction tower. The gas is condensed and enters the falling film reactor. The condensed ethanol continues to participate in the reaction, and HCL enters the gas-liquid separator. The HCL generated in the falling film reactor also enters the gas-liquid separator. After passing through the gas-liquid separator, the HCL enters the hydrochloric acid recovery unit, and the ethanol is sent to the reaction tower, effectively recovering the HCL and avoiding waste and pollution of the ethanol. The reaction liquid obtained after the reaction of the reaction tower falls into the first receiving kettle. In order to control the stability of the liquid level and maintain the balance of feeding and discharging, a small part of the reaction liquid is returned to the reaction tower through the reflux tower to maintain the balance, and most of the reaction liquid is sent to the stripping tower. After entering the stripping tower, the substances in the reaction liquid that have not fully reacted fully react with the vaporized ethanol rising in the tower, and the ethanol flow is adjusted at any time to control the temperature at the top of the tower at 70-100℃. At the same time, the reaction liquid is washed with alcohol, which also effectively reduces the content of chloride ions. The liquid that has completely reacted falls into the second receiving kettle at the bottom of the tower. At this time, the main content of the liquid can reach more than 98.5%, and the chloride ion content is less than 5 PPM. The reacted liquid is directly transported to the falling film evaporator, and the substances with a relatively low boiling point (mostly excess ethanol) are evaporated into the receiving tank. The receiving tank returns the ethanol to the reflux tank to complete the reflux utilization of the ethanol. The product falls into the temporary storage tank. At this time, the main content of the product can reach more than 99.5%, which not only purifies the product, but also recovers the ethanol.

[0042] Example 1

[0043] A method for producing chloropropyl triethoxysilane by connecting two towers for esterification, the specific method is as follows:

[0044] (1) First, the anhydrous ethanol gas is introduced into the stripping tower, 1 / 3 of the ethanol gas is condensed and introduced into the falling film reactor after coming out of the stripping tower, and chloropropyl trichlorosilane is also introduced into the falling film reactor. The liquid ethanol and chloropropyl trichlorosilane are preliminarily reacted to generate semi-finished products, which are introduced into the reaction tower, and 2 / 3 of the ethanol gas is introduced into the reaction tower;

[0045] (2) In the reaction tower, the ethanol gas and the semi-finished products are subjected to esterification reaction to obtain reaction liquid, which falls into the first receiving tank, part of the reaction liquid is refluxed back to the reaction tower, and the other part of the reaction liquid is sent to the stripping tower, and the liquid level in the first receiving tank is 70%;

[0046] (3) After the reaction liquid in the stripping tower is fully reacted with the ethanol gas, the liquid falls into the second receiving tank, and then is subjected to post-treatment to obtain chloropropyl triethoxysilane and ethanol;

[0047] Wherein, the molar ratio of chloropropyl trichlorosilane to anhydrous ethanol is 1:0.66, the temperature of anhydrous ethanol gasification is 125℃, the bottom temperature of the stripping tower is controlled at 120℃, and the top temperature reaches 80℃; the top temperature of the reaction tower is 40℃, the flow rate of chloropropyl triethoxysilane entering the falling film reactor is controlled at 500kg / h, and the flow rate of ethanol entering the falling film reactor is 110kg / h; the temperature of the falling film evaporator in the post-treatment is 125℃, and the pressure in the temporary storage tank in the post-treatment is -0.85kPa.

[0048] The product obtained by the above method contains 98.5% before post-treatment, the main content is 99.8% after post-treatment, the yield is 99.5%, and the chloride ion is less than 5PPM.

Claims

1. A system for the continuous production of chloropropyltriethoxysilane by means of a double column esterification comprising a reaction column, an anhydrous ethanol tank and a chloropropyltrichlorosilane tank, characterized in that, The first receiving kettle is arranged at the bottom of the reaction tower, and the second receiving kettle is arranged at the bottom of the stripping tower; the anhydrous ethanol storage tank is sequentially connected with the gasifier, the stripping tower, the condenser A, and the falling film reactor, and the chloropropyltrichlorosilane storage tank is connected with the falling film reactor; the falling film reactor is sequentially connected with the top of the reaction tower, the first receiving kettle, and the stripping tower, and the top of the stripping tower is connected with the bottom of the reaction tower; the second receiving kettle is connected with the post-processing device; Flow regulating valves are arranged on the pipelines of the condenser A and the reaction tower which are connected with the stripping tower respectively. The top of the reaction tower is sequentially connected with the tower top condenser B, the falling film reactor, and the gas-liquid separator, and the gas-liquid separator is connected with the hydrochloric acid absorption unit and the reaction tower respectively. The reaction temperature of the falling film reactor is normal temperature.

2. The system for the production of chloropropyltriethoxysilane by continuous esterification in two columns according to claim 1, characterized in that, The first receiving kettle is connected with the reflux tower, and the reflux tower is connected with the bottom of the reaction tower; flow regulating valves are arranged on the pipelines of the reflux tower and the stripping tower which are connected with the first receiving kettle respectively.

3. The system for the production of chloropropyltriethoxysilane by continuous esterification in two columns according to claim 1, characterized in that, A reflux tank is further arranged between the condenser A and the falling film reactor.

4. The system for the production of chloropropyltriethoxysilane by continuous esterification in two columns according to claim 3, characterized in that, The post-processing device comprises a falling film evaporator, and the second receiving kettle is sequentially connected with the falling film evaporator and the temporary storage tank; the top of the falling film evaporator is sequentially connected with the condenser C and the receiving tank; the receiving tank is connected with the reflux tank, and a pump is arranged between the receiving tank and the reflux tank.

5. A process for the production of chloropropyltriethoxysilane by a two-column continuous esterification characterized in that, The method for generating chloropropyltriethoxysilane by using the system of any one of claims 1-4 comprises the following steps: (1) first, anhydrous ethanol gas is gasified and introduced into the stripping tower, part of the ethanol gas is condensed and introduced into the falling film reactor after being discharged from the stripping tower, chloropropyltrichlorosilane is introduced into the falling film reactor, liquid ethanol and chloropropyltrichlorosilane are preliminarily reacted to generate a semi-finished product which is introduced into the reaction tower, and the other part of the ethanol gas is introduced into the reaction tower; (2) the ethanol gas and the semi-finished product in the reaction tower are reacted to generate a reaction liquid which falls into the first receiving kettle, and then the reaction liquid is introduced into the stripping tower; (3) the reaction liquid introduced into the stripping tower is fully reacted with the ethanol gas, and then the liquid falls into the second receiving kettle, and then chloropropyltriethoxysilane is obtained after post-processing, and ethanol is recovered.

6. A process for the production of chloropropyltriethoxysilane by a two-column continuous esterification according to claim 5, characterized in that, The molar ratio of chloropropyltrichlorosilane to anhydrous ethanol is 1:0.66-0.

67.

7. A process for the production of chloropropyl triethoxysilane by continuous esterification in two columns according to claim 5, characterized in that, In step (1), the part of the ethanol gas is 1 / 3 of the ethanol gas, and the other part of the ethanol gas is 2 / 3 of the ethanol gas; in step (2), the liquid level in the first receiving kettle is 50-70 %.

8. A process for the production of chloropropyl triethoxysilane by continuous esterification in two columns as claimed in claim 5 wherein, The temperature of the anhydrous ethanol gasification is 115-135 ℃; the bottom temperature of the stripping tower is controlled at 110-135 ℃, and the top temperature reaches 70-100 ℃; and the top temperature of the reaction tower is 30-90 ℃.

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