A chlorosilane bond breaking rearrangement system and process

Abstract

The invention discloses a chlorosilane bond breaking rearrangement system and process, comprising the following steps: low-boiling substances, monomethyl and / or trimethyl obtained by an organosilicon distillation process are mixed in proportion and then heated and vaporized, and after heat treatment, a catalytic bond breaking rearrangement reaction is performed to obtain a dimethyl product; wherein the matrix of the catalyst is aluminum chloride, and the active components are metal tin and copper, the mass percentage of tin in aluminum chloride is 0.1%-5%, and the mass percentage of copper in aluminum chloride is 1%-10%. After different monomers are mixed and fed in a certain proportion, they are heated to a certain temperature, and bond breaking rearrangement is performed in a rearrangement reactor to obtain useful products, thereby reducing the amount of by-products.

Description

Technical Field

[0001] The invention belongs to the technical field of bond breaking and rearrangement of organic compounds, and in particular relates to a chlorosilane bond breaking and rearrangement system and process. Background Art

[0002] The statements herein merely provide background information related to the present invention and do not necessarily constitute prior art.

[0003] At present, in the crude monomer products of the silicone monomer industry, in addition to the target product dimethyldichlorosilane (dimethyl, which accounts for 80-85%), there are still many other chlorosilane by-products, including monomethyltrichlorosilane (monomethyl), trimethylmonochlorosilane (trimethyl), methylhydrogendichlorosilane (monomethyl containing hydrogen), dimethylhydrogenmonochlorosilane (dimethyl containing hydrogen), low-boiling substances, high-boiling substances and azeotropes. The crude monomer needs to be further distilled and purified to obtain dimethyl, and the above-mentioned various methylchlorosilanes are produced as by-products. Although the above-mentioned various methylchlorosilanes have certain added value, the supporting treatment system is relatively complex and requires a large investment. Most manufacturers only use one or several devices to process the corresponding methylchlorosilane by-products, and sell the others at a low price.

[0004] Therefore, in addition to improving the selective yield of dimethylformamide in crude monomers in the upstream reaction system, some manufacturers also choose to take some measures in the distillation system to comprehensively utilize by-products to reduce the output of by-products. However, the comprehensive utilization efficiency of by-products is relatively low, making it difficult to achieve effective utilization. Summary of the invention

[0005] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a chlorosilane bond breaking and rearrangement system and process, in which different monomers are mixed and fed in a certain proportion, heated to a certain temperature, and the bonds are broken and rearranged in a rearrangement reactor to obtain useful products, thereby reducing the amount of by-products.

[0006] In order to achieve the above object, the present invention is implemented through the following technical solutions:

[0007] In a first aspect, the present invention provides a chlorosilane bond breaking and rearrangement process, comprising the following steps:

[0008] The low-boiling substances, monomethyl and / or trimethyl obtained by the organosilicon distillation process are mixed in proportion and then heated and vaporized. After heat treatment, a catalytic bond breaking and rearrangement reaction is carried out to obtain a dimethyl product.

[0009] The matrix of the catalyst is aluminum chloride, and the active components are metal tin and copper. The mass percentage of tin in the aluminum chloride is 0.1%-5%, and the mass percentage of copper in the aluminum chloride is 1%-10%.

[0010] In a second aspect, the present invention provides a chlorosilane bond breaking rearrangement system, comprising: a feed tank, a heater, a vaporizer, a superheater and a rearrangement reactor connected in sequence, wherein:

[0011] The feed tank is respectively connected to a low-boiling-point source, a monomethyl source and / or a trimethyl source;

[0012] The rearrangement reactor is filled with a catalyst, the matrix of the catalyst is aluminum chloride, the active components are metal tin and copper, the mass percentage of tin to aluminum chloride is 0.1%-5%, and the mass percentage of copper to aluminum chloride is 1%-10%.

[0013] The beneficial effects achieved by one or more embodiments of the present invention are as follows:

[0014] Under certain reaction conditions, a variety of methylchlorosilane bonds are broken and rearranged to obtain more target products through the catalysis of a special catalytic system. This can greatly reduce the amount of methylchlorosilane by-products, increase the selective yield of the target product dimethyl, and also improve the operating level of the entire organic silicon monomer unit.

[0015] In the catalyst, copper can initiate the reaction, tin can accelerate the reaction, and aluminum chloride, as the main substance, cooperates with copper and tin to promote the formation of the target product and improve the yield of the target product. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0017] Figure 1 It is a schematic structural diagram of a chlorosilane bond breaking and rearrangement system according to one or more embodiments of the present invention.

[0018] In the figure: the distances or sizes between parts are exaggerated to show the positions of the parts, and the schematic diagram is for illustration only;

[0019] Among them, 1-feed tank; 2-feed pump; 3-heater; 4-vaporizer; 5-superheater; 6-rearrangement reactor; 7-cooler; 8-receiving tank. DETAILED DESCRIPTION

[0020] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0021] In a first aspect, the present invention provides a chlorosilane bond breaking and rearrangement process, comprising the following steps:

[0022] The low-boiling substances, monomethyl and / or trimethyl obtained by the organosilicon distillation process are mixed in proportion and then heated and vaporized. After heat treatment, a catalytic bond breaking and rearrangement reaction is carried out to obtain a dimethyl product; wherein the matrix of the catalyst is aluminum chloride, and the active ingredients are metallic tin and copper, the mass percentage of tin in the aluminum chloride is 0.1%-5%, and the mass percentage of copper in the aluminum chloride is 1%-10%.

[0023] In some embodiments, the mass ratio of low boiling point substances, monomethyl methacrylate and trimethyl methacrylate is 1:1-5:1-5, preferably 1:2:2.

[0024] In some embodiments, the temperature after the superheat treatment is greater than 240°C.

[0025] Preferably, the temperature after the overheat treatment is 240-300°C.

[0026] If the temperature of the superheat treatment is too low, liquid may be brought in, which is not conducive to the reaction. If the temperature is too high, it may easily cause catalyst poisoning, reduce catalytic performance and catalyst service life.

[0027] Preferably, the degree of superheat of the mixed material after superheat treatment is greater than or equal to 8.

[0028] Gas phase feeding requires a certain degree of superheat, so superheating the mixed material can ensure the smooth feeding of the gas phase mixed material.

[0029] In some embodiments, the pressure of the catalytic bond-breaking rearrangement reaction is 0.5-1.0 MPa and the temperature is 200-280° C. If the temperature is too low, the conditions for the catalytic reaction cannot be met and the reaction efficiency is low. If the temperature is too high, the catalyst is poisoned and deactivated.

[0030] Preferably, during the bond breaking rearrangement reaction, the gas velocity of the mixed material is 0.05-1.0 m / s, and the reaction time is 10-120 s. A high gas velocity and a short residence time, or a low gas velocity and a long residence time are not conducive to the reaction.

[0031] In a second aspect, the present invention provides a chlorosilane bond breaking rearrangement system, comprising: a feed tank, a heater, a vaporizer, a superheater and a rearrangement reactor connected in sequence, wherein:

[0032] The feed tank is respectively connected to a low-boiling-point source, a monomethyl source and / or a trimethyl source;

[0033] The rearrangement reactor is filled with a catalyst, the matrix of the catalyst is aluminum chloride, the active components are metal tin and copper, the mass percentage of tin to aluminum chloride is 0.1%-5%, and the mass percentage of copper to aluminum chloride is 1%-10%.

[0034] In some embodiments, the mass percentage of tin in the aluminum chloride is 2%-4%, and the mass percentage of copper in the aluminum chloride is 4%-6%.

[0035] In some embodiments, the discharge port of the rearrangement reactor is connected to a cooler.

[0036] Preferably, the outlet of the cooler is connected to the material receiving tank.

[0037] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0038] Example 1

[0039] like Figure 1 As shown, a chlorosilane bond breaking and rearrangement system includes a feed tank 1, a feed pump 2, a heat exchanger 3, a vaporizer 4, a superheater 5, a rearrangement reactor 6, a cooler 7, a receiving tank 8 and other equipment and connecting pipes.

[0040] The low-boiling substances, mono- and tri-methyl obtained in the organosilicon distillation process are mixed in a certain proportion and enter the rearrangement feed tank. After being pressurized by the delivery pump, they are heated and vaporized by the heat medium, and then enter the rearrangement reactor after superheat treatment. Under specific temperature and pressure conditions, the mixed gas phase materials are catalyzed by the catalyst for bond breaking and rearrangement to obtain the target product with a predetermined content.

[0041] The feed is low-boiling substances and monomethyl ether, which enter the feed tank 1 at a mass ratio of 2:1. After being mixed evenly, the feed pump 2 delivers the feed, and the total feed rate is controlled to be about 3500 kg / h. Then, it is heated to 250°C by the heat exchanger 3, the vaporizer 4 and the superheater 5, and enters the rearrangement reactor 6.

[0042] The temperature of the rearrangement reaction is controlled between 240-250°C, the reaction pressure is 0.7MPa, the matrix of the catalyst is aluminum chloride, the active ingredients are metal tin and copper, the mass percentage of tin in aluminum chloride is 3%, the mass percentage of copper in aluminum chloride is 5%, and the rearrangement reaction time is 50s.

[0043] Ceramic balls are used as catalyst supports, and the catalyst is dried and dehydrated before being put into operation. The catalyst is discharged from the bottom of the reactor and heat-exchanged with the feed through the heat exchanger 3, and then cooled by the cooler 7 and collected in the receiving tank 8. The reaction product is tested to have a dimethyl content of about 55%.

[0044] Example 2

[0045] The feed is low boiling point, methyl methacrylate and trimethyl methacrylate, and the mass ratio is about 1:2:2. It enters the feed tank 1, and is evenly mixed and transported by the feed pump 2. The total feed amount is controlled to be about 4000Kg / h. It is then heated to 260℃ by the heat exchanger 3, the vaporizer 4, and the superheater 5, and enters the rearrangement reactor 6. The matrix of the catalyst is aluminum chloride, and the active ingredients are metal tin and copper. The mass percentage of tin in aluminum chloride is 4%, and the mass percentage of copper in aluminum chloride is 6%. The reaction temperature is controlled at about 240℃, the reaction pressure is 0.6MPa, and the reaction time is 55s.

[0046] The product discharged from the bottom of the reactor is heat exchanged with the feed through the heat exchanger 3, cooled by the cooler 7, and collected in the receiving tank 8. The reaction product was tested and the dimethyl content was about 66%.

[0047] Example 3

[0048] The feed is low boiling point, methyl methacrylate and trimethyl methacrylate, and the ratio is about 1:2:2. After being mixed evenly, it is transported by feed pump 2, and the total feed amount is controlled to be about 4000Kg / h. Then it is heated to 250℃ by heat exchanger 3, vaporizer 4 and superheater 5, and enters rearrangement reactor 6. The matrix of the catalyst is aluminum chloride, and the active ingredients are metal tin and copper. The mass percentage of tin in aluminum chloride is 3%, and the mass percentage of copper in aluminum chloride is 4%. The reaction temperature is controlled at about 230℃, the reaction pressure is 0.6MPa, and the reaction time is 52s.

[0049] The product discharged from the bottom of the rearrangement reactor 6 is heat exchanged with the feed in the heat exchanger 3, cooled by the cooler 7, and collected in the receiving tank 8. The reaction product was tested and the dimethyl content was about 52%.

[0050] Example 4

[0051] The difference from Example 1 is that the matrix of the catalyst is aluminum chloride, the active ingredients are metal tin and copper, the mass percentage of tin in aluminum chloride is 2%, and the mass percentage of copper in aluminum chloride is 4%. The reaction product is tested and the content of dimethylformamide is about 50%.

[0052] Example 5

[0053] The difference from Example 1 is that the matrix of the catalyst is aluminum chloride, the active ingredients are metal tin and copper, the mass percentage of tin in aluminum chloride is 1%, and the mass percentage of copper in aluminum chloride is 8%. The reaction product is tested and the content of dimethylformamide is about 40%.

[0054] Example 6

[0055] The difference from Example 1 is that the matrix of the catalyst is aluminum chloride, the active ingredients are metal tin and copper, the mass percentage of tin in aluminum chloride is 0.1%, and the mass percentage of copper in aluminum chloride is 1%. The reaction product is tested and the content of dimethylformamide is about 20%.

[0056] Example 7

[0057] The difference from Example 1 is that the matrix of the catalyst is aluminum chloride, the active ingredients are metal tin and copper, the mass percentage of tin in aluminum chloride is 5%, and the mass percentage of copper in aluminum chloride is 10%. The reaction product is tested and the content of dimethylformamide is about 25%.

[0058] Example 8

[0059] The difference from Example 1 is that the matrix of the catalyst is aluminum chloride, the active ingredients are metal tin and copper, the mass percentage of tin in aluminum chloride is 3%, and the mass percentage of copper in aluminum chloride is 10%. The reaction product is tested and the content of dimethylformamide is about 42%.

[0060] Example 9

[0061] The difference from Example 1 is that the matrix of the catalyst is aluminum chloride, the active ingredients are metal tin and copper, the mass percentage of tin in aluminum chloride is 0.1%, and the mass percentage of copper in aluminum chloride is 5%. The reaction product is tested and the content of dimethylformamide is about 33%.

[0062] Comparative Example 1

[0063] The difference from Example 1 is that the matrix of the catalyst is aluminum chloride, the active ingredients are metal tin and copper, the mass percentage of tin in aluminum chloride is 6%, and the mass percentage of copper in aluminum chloride is 5%. The reaction product is tested and the content of dimethylformamide is about 15%.

[0064] Comparative Example 2

[0065] The difference from Example 1 is that the matrix of the catalyst is aluminum chloride, the active ingredients are metal tin and copper, the mass percentage of tin in aluminum chloride is 6%, and the mass percentage of copper in aluminum chloride is 11%. The reaction product is tested and the content of dimethylformamide is about 9%.

[0066] Comparative Example 3

[0067] The difference from Example 1 is that the catalyst matrix is ​​aluminum chloride and copper is omitted. The reaction product is tested and the dimethylformamide content is about 5%.

[0068] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A chlorosilane bond breaking and rearrangement process, characterized in that: The steps include: The low-boiling substances, monomethyl and / or trimethyl obtained by the organosilicon distillation process are mixed in proportion and then heated and vaporized. After heat treatment, a catalytic bond breaking and rearrangement reaction is carried out to obtain a dimethyl product. The matrix of the catalyst is aluminum chloride, and the active ingredients are metal tin and copper, the mass percentage of tin in aluminum chloride is 2%-4%, and the mass percentage of copper in aluminum chloride is 4%-6%; The mass ratio of low boiling point substances, monomethyl methacrylate and trimethyl methacrylate is 1:1-5:1-5; The catalyst is filled in the rearrangement reactor; The temperature after overheating treatment is greater than 240-300°C; The superheat degree of the mixed material after superheat treatment is greater than or equal to 8; The pressure of catalytic bond breaking rearrangement reaction is 0.5-1.0MPa and the temperature is 200-280℃; During the bond-breaking rearrangement reaction, the gas velocity of the mixed material is 0.05-1.0 m / s, and the reaction time is 10-120 s.

2. A chlorosilane bond breaking and rearrangement device, characterized in that: include: A feed tank, a heater, a vaporizer, a superheater and a rearrangement reactor are connected in sequence, wherein: The feed tank is respectively connected to a low-boiling-point source, a monomethyl source and / or a trimethyl source; The rearrangement reactor is filled with a catalyst, the matrix of the catalyst is aluminum chloride, the active components are metal tin and copper, the mass percentage of tin to aluminum chloride is 2%-4%, and the mass percentage of copper to aluminum chloride is 4%-6%.

3. The chlorosilane bond breaking and rearrangement device according to claim 2, characterized in that: The discharge port of the rearrangement reactor is connected to a cooler.

4. The chlorosilane bond breaking and rearrangement device according to claim 2, characterized in that: The outlet of the cooler is connected to the material receiving tank.

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