Method and equipment for producing tert-dodecanethiol

Abstract

The invention relates to the technical field of chemical production, and discloses a method for producing tert-dodecanethiol, which comprises the following steps: uniformly mixing dodecene and a catalyst, introducing hydrogen sulfide gas, controlling the reaction temperature to be lower than 80 DEG C, finishing the reaction when the change amplitude of the reaction temperature is less than 10 DEG C, washing and rectifying the reaction product to obtain the tert-dodecanethiol. A tert-dodecanethiol finished product is obtained; wherein the catalyst is a mixture of aluminum trichloride, carbon tetrachloride and diethyl ether. The method has the following technical effects that the mixture of aluminum trichloride, carbon tetrachloride and diethyl ether is used as the catalyst, so that the yield and purity of the tert-dodecanethiol finished product are effectively improved, the product quality is good, the performance is stable, the production process flow is simple, the raw materials are non-toxic, and the environmental pollution is small. The invention also discloses equipment for producing tert-dodecanethiol.

Description

Technical Field

[0001] The invention belongs to the technical field of chemical production, and specifically relates to a method and equipment for producing tert-dodecyl mercaptan. Background Art

[0002] Tert-dodecyl mercaptan (TDM) is an important chemical substance. It can be used as a molecular weight regulator in the polymerization process of ABS resin, styrene-butadiene rubber, nitrile rubber, high-impact polystyrene and other products. It can also be used as a stabilizer and antioxidant for polyolefins such as polyvinyl chloride and polyethylene. It can also be used to synthesize certain drugs, non-ionic surfactants, lubricant additives, pesticides, fungicides, fragrances and other products. The production methods of tert-dodecyl mercaptan mainly include the dodecanol high temperature and high pressure method, the dodecyl chloride method and the dodecene hydrogen sulfide direct addition method.

[0003] Dodecene hydrogen sulfide direct addition method mainly uses dodecene and hydrogen sulfide as raw materials, adds catalyst to promote addition reaction, and obtains tert-dodecyl mercaptan, wherein, catalyst usually adopts solid AlCl .But due to solid AlCl and mixed dodecene are not miscible, directly using as catalyst can cause poor mass transfer efficiency, low reaction activity and other problems, and the yield and purity of the obtained tert-dodecyl mercaptan finished product are undesirable.In the prior art, by adopting solid AlCl , the mixture of toluene and HCl participates in the addition reaction of dodecene and hydrogen sulfide as catalyst, although the mass transfer efficiency and reaction activity of catalyst are improved to a certain extent, because HCl is highly toxic, highly corrosive material, post-processing cost is high, and also can bring adverse effects to environment and human body, and the yield and purity of finished product also still need to be further improved. Summary of the invention

[0004] In order to solve the deficiencies of the prior art, the present invention provides a method for producing tert-dodecyl mercaptan, which effectively improves the yield and purity of the finished product of tert-dodecyl mercaptan by using a mixture of aluminum trichloride, carbon tetrachloride and ether as a catalyst, and has good product quality and stable performance, and the production process is simple, low in cost, non-toxic raw materials, and little environmental pollution. The present invention also provides a device for producing tert-dodecyl mercaptan.

[0005] The technical effects to be achieved by the present invention are achieved through the following technical aspects:

[0006] In a first aspect, the present invention provides a method for producing tert-dodecyl mercaptan, comprising the following steps:

[0007] Dodecene and the catalyst are uniformly mixed, hydrogen sulfide gas is introduced, the reaction temperature is controlled to be lower than 80°C, preferably 10-80°C, and the reaction is completed when the change range of the reaction temperature is less than 10°C. The reaction product is washed with water and distilled to obtain a finished product of tert-dodecyl mercaptan;

[0008] Wherein, the catalyst is a mixture of aluminum chloride, carbon tetrachloride and ether. Aluminum chloride, as a strong Lewis acid catalyst, itself has high catalytic performance. The addition of carbon tetrachloride and ether can improve the mass transfer efficiency of the catalyst, further enhance the stability and catalytic activity of the catalyst, effectively improve the reaction efficiency, and then improve the yield of the finished product. At the same time, the addition of carbon tetrachloride and ether can improve the stability and reusability of the aluminum chloride catalyst, thereby helping to reduce production costs and reduce the generation of production waste.

[0009] The reaction formula of the dodecene and the hydrogen sulfide gas is as follows:

[0010]

[0011] Catalyst is a catalyst, specifically a mixture of aluminum trichloride, carbon tetrachloride and ether.

[0012] As a further description of the technical solution of the present invention, in the catalyst, the mass ratio of aluminum chloride, carbon tetrachloride and diethyl ether is (1-3):1:(1-3), preferably 2:1:2. The catalyst prepared by adopting this mixing ratio has the best catalytic performance, can achieve a high conversion rate, and effectively improve the yield of the finished product.

[0013] As a further description of the technical solution of the present invention, the mass ratio of the dodecene to the catalyst is 1:0.1-0.3, and the mass ratio of the dodecene to the hydrogen sulfide is 1:0.1-0.3.

[0014] As a further description of the technical solution of the present invention, the temperature of the dodecene is lower than 10°C, and the temperature of the mixed solution of the dodecene and the catalyst is 10-80°C.

[0015] As a further description of the technical solution of the present invention, the reaction pressure is lower than 0.8 MPa, preferably 0.1 to 0.8 MPa, and the reaction time is 1 to 4 hours.

[0016] Since tert-dodecyl mercaptan is a compound with a high boiling point and a low decomposition temperature, its boiling point is about 240°C under normal pressure, but it is easy to decompose at about 150°C. Therefore, the use of low temperature and low pressure reaction conditions is beneficial to inhibiting the decomposition of the reaction product tert-dodecyl mercaptan, and is also beneficial to controlling the chromaticity of the finished tert-dodecyl mercaptan, which can ensure both the yield and the quality of the finished product.

[0017] As a further description of the technical solution of the present invention, the inlet flow rate of the hydrogen sulfide gas is 3-8 L / min.

[0018] In a second aspect, the present invention provides an apparatus for producing tert-dodecyl mercaptan, which is used to implement the above-mentioned method for producing tert-dodecyl mercaptan, comprising a reaction kettle, a water washing tower, a distillation tower and a finished product tank connected in sequence;

[0019] The reactor is provided with a first feed inlet, a second feed inlet and a third feed inlet, and the first feed inlet, the second feed inlet and the third feed inlet are used to input the dodecene, the catalyst and the hydrogen sulfide gas respectively.

[0020] As a further description of the technical solution of the present invention, the equipment for producing tert-dodecyl mercaptan also includes a mixing kettle and a pressure pump, the feed port of the mixing kettle is connected to the discharge port of the reactor, the pressure pump is arranged at the discharge port of the mixing kettle, and the pressure pump is used to transport the material output from the mixing kettle back to the reactor.

[0021] As a further description of the technical solution of the present invention, the equipment for producing tert-dodecyl mercaptan also includes a primary separation tower, the primary separation tower is provided with a fourth feed port, a first discharge port and a second discharge port, the first discharge port and the second discharge port are respectively located at the top and the bottom of the primary separation tower, and the fourth feed port is located between the first discharge port and the second discharge port;

[0022] The fourth feed port is communicated with the discharge port of the water washing tower, the first discharge port is communicated with the first feed port, and the second discharge port is communicated with the feed port of the distillation tower.

[0023] As a further description of the technical solution of the present invention, a magnetic stirrer is provided in the reaction kettle.

[0024] In summary, the present invention has at least the following benefits:

[0025] 1. The method for producing tert-dodecyl mercaptan provided by the present invention adopts a mixture of aluminum trichloride, carbon tetrachloride and diethyl ether as a catalyst, thereby improving the mass transfer efficiency of the catalyst, effectively promoting the reaction, thereby improving the addition reaction efficiency of dodecene and hydrogen sulfide, and improving the yield of the tert-dodecyl mercaptan product; the reaction process basically has no side reaction, does not introduce impurities, improves the purity of the tert-dodecyl mercaptan product, and has good product quality and stable performance; at the same time, the production process is simple, the cost is low, the raw materials are non-toxic, and it is environmentally friendly.

[0026] 2. The equipment for producing tert-dodecyl mercaptan provided by the present invention realizes the reaction of dodecene and hydrogen sulfide through a reactor. The reactor has good airtightness, can better control the reaction temperature and reaction pressure, and keep the reaction at a lower temperature and a lower pressure, which is beneficial to inhibiting the decomposition of the reaction product tert-dodecyl mercaptan and ensuring the yield of the finished tert-dodecyl mercaptan. At the same time, the use of the reactor can also realize the batch production of tert-dodecyl mercaptan, which is beneficial to better control the production quality of each batch and ensure the quality of the finished product. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a schematic structural diagram of an apparatus for producing tert-dodecyl mercaptan according to Example 4 of the present invention;

[0028] Figure 2 This is a schematic structural diagram of an apparatus for producing tert-dodecyl mercaptan according to Example 5 of the present invention;

[0029] Figure 3 This is a schematic diagram of the structure of the reactor of Example 5 of the present invention.

[0030] Markings in the figure:

[0031] 1. Reactor; 11. First feed inlet; 12. Second feed inlet; 13. Third feed inlet; 14. Magnetic stirrer;

[0032] 2. Water washing tower; 3. Distillation tower; 4. Finished product tank; 5. Mixing kettle; 6. Pressure pump;

[0033] 7. Primary separation tower; 71. Fourth feed inlet; 72. First discharge outlet; 73. Second discharge outlet. DETAILED DESCRIPTION

[0034] In order to facilitate the understanding of the present invention, the present invention will be described more comprehensively below in conjunction with specific embodiments and accompanying drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thoroughly understood.

[0035] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0036] Example 1

[0037] This embodiment provides a tert-dodecyl mercaptan, which is produced by the following method steps:

[0038] 200 kg of dodecene is cooled to below 10° C. and fed into a reactor. A quantitative pump is used to pump 60 kg of a catalyst (the mass ratio of aluminum chloride, carbon tetrachloride and ether is 2:1:2) into the reactor at a flow rate of 0.8 L / min. After the dodecene and the catalyst are uniformly mixed in the reactor, 60 kg of hydrogen sulfide gas is introduced into the reactor at a flow rate of 5 L / min. The temperature in the reactor is controlled to be between 10 and 80° C. and the pressure is controlled to be between 0.1 and 0.8 MPa. When the reaction temperature in the reactor changes by less than 10° C., the reaction is completed. The reaction product is washed with water in a water washing tower and rectified in a distillation tower to obtain a finished product of tert-dodecyl mercaptan.

[0039] Example 2

[0040] This embodiment provides a tert-dodecyl mercaptan, which is produced by the following method steps:

[0041] 200 kg of dodecene is cooled to below 10° C. and fed into a reactor. A quantitative pump is used to pump 40 kg of a catalyst (the mass ratio of aluminum chloride, carbon tetrachloride and ether is 2:1:2) into the reactor at a flow rate of 0.1 L / min. After the dodecene and the catalyst are uniformly mixed in the reactor, 40 kg of hydrogen sulfide gas is introduced into the reactor at a flow rate of 3 L / min. The temperature in the reactor is controlled to be between 10 and 80° C. and the pressure is controlled to be between 0.1 and 0.8 MPa. When the reaction temperature in the reactor changes by less than 10° C., the reaction is completed. The reaction product is washed with water in a water washing tower and rectified in a distillation tower to obtain a finished product of tert-dodecyl mercaptan.

[0042] Example 3

[0043] This embodiment provides a tert-dodecyl mercaptan, which is produced by the following method steps:

[0044] 200 kg of dodecene is cooled to below 10° C. and fed into a reactor. A quantitative pump is used to pump 20 kg of a catalyst (the mass ratio of aluminum chloride, carbon tetrachloride and ether is 2:1:2) into the reactor at a flow rate of 1.2 L / min. After the dodecene and the catalyst are uniformly mixed in the reactor, 20 kg of hydrogen sulfide gas is introduced into the reactor at a flow rate of 8 L / min. The temperature in the reactor is controlled to be between 10 and 80° C. and the pressure is controlled to be between 0.1 and 0.8 MPa. When the reaction temperature in the reactor changes by less than 10° C., the reaction is completed. The reaction product is washed with water in a water washing tower and rectified in a distillation tower to obtain a finished product of tert-dodecyl mercaptan.

[0045] Comparative Example 1

[0046] This comparative example provides a tert-dodecyl mercaptan, which is produced by the following method steps:

[0047] 200 kg of dodecene is cooled to below 10° C. and fed into a reactor, and 60 kg of powdered aluminum chloride catalyst is added into the reactor; after dodecene and the catalyst are uniformly mixed in the reactor, 60 kg of hydrogen sulfide gas is introduced into the reactor at a flow rate of 5 L / min; the temperature in the reactor is controlled between 10 and 80° C. and the pressure is controlled between 0.1 and 0.8 MPa. When the reaction temperature in the reactor changes by less than 10° C., the reaction is completed, and the reaction product is washed with water in a water washing tower and rectified in a distillation tower to obtain a finished product of tert-dodecyl mercaptan.

[0048] Test Example 1

[0049] In this test example, the yields of the finished tert-dodecyl mercaptan products prepared in Examples 1 to 3 and Comparative Example 1 were calculated and the purity was determined. The yield and purity data of the finished tert-dodecyl mercaptan products are shown in Table 1.

[0050] Table 1 Yield and purity of finished tert-dodecyl mercaptan products of Examples 1 to 3 and Comparative Example 1

[0051] Example / Comparative Example Yield (%) purity(%) Example 1 88.1 99.4 Example 2 85.8 99.1 Example 3 86.9 99.3 Comparative Example 1 81.0 98.6

[0052] By comparing the yield and purity data of the tert-dodecyl mercaptan finished products of Examples 1 to 3 and Comparative Example 1, it can be seen that the yield and purity of the tert-dodecyl mercaptan finished products of Examples 1 to 3 are higher than those of Comparative Example 1, especially Example 1, whose yield is 7.1% higher and purity is 0.8% higher than that of Comparative Example 1. This proves that the catalytic performance of using a mixture of aluminum trichloride, carbon tetrachloride and diethyl ether as a catalyst is better than the catalytic performance of using aluminum trichloride alone as a catalyst, effectively improving the addition reaction efficiency of dodecene and hydrogen sulfide, and significantly improving the yield and purity of the tert-dodecyl mercaptan finished product.

[0053] Example 4

[0054] refer to Figure 1 The equipment for producing tert-dodecyl mercaptan provided in this embodiment is used for the production of tert-dodecyl mercaptan in embodiment 1, 2 or 3. The equipment for producing tert-dodecyl mercaptan comprises a reactor 1, a water washing tower 2, a distillation tower 3 and a finished product tank 4 connected in sequence. The reactor 1 is provided with a first feed port 11, a second feed port 12 and a third feed port 13, and the first feed port 11, the second feed port 12 and the third feed port 13 are used to input dodecene, a catalyst and hydrogen sulfide gas respectively.

[0055] It can be understood that the reactor 1, the water washing tower 2, the distillation tower 3 and the finished product tank 4 are connected in sequence. During production, the raw material dodecene is fed into the reactor 1 from the first feed port 11, and the catalyst is fed into the reactor 1 from the second feed port 12. After the dodecene and the catalyst are evenly mixed in the reactor 1, the hydrogen sulfide gas is introduced into the reactor 1 from the third feed port 13 to react with dodecene. After the reaction is completed, the reaction product is transported to the water washing tower 2 for water washing to remove impurities. After the water washing is completed, it is transported to the distillation tower 3 for refining, and finally transported to the finished product tank 4 for storage.

[0056] The equipment for producing tert-dodecyl mercaptan in this embodiment realizes the reaction of dodecene and hydrogen sulfide by setting a reactor. Since the reactor has good airtightness, the reaction temperature and reaction pressure can be better controlled, and the reaction is kept at a lower temperature and a lower pressure, which is beneficial to inhibiting the decomposition of the reaction product tert-dodecyl mercaptan and ensuring the yield of the finished tert-dodecyl mercaptan. At the same time, the use of the reactor can also realize the batch production of tert-dodecyl mercaptan, which is beneficial to better control the production quality of each batch and ensure the quality of the finished product.

[0057] Example 5

[0058] As a further optimization of Example 4, refer to Figures 2 to 3 The equipment for producing tert-dodecyl mercaptan further includes a mixing kettle 5 and a pressure pump 6. The feed port of the mixing kettle 5 is connected to the discharge port of the reactor 1, and the reaction product in the reactor 1 can be transported to the mixing kettle 5 through the discharge port of the reactor 1. The pressure pump 6 is arranged at the discharge port of the mixing kettle 5, and the pressure pump 6 is used to transport the material output from the mixing kettle 5 back to the reactor 1.

[0059] It is understandable that the discharge port of the reactor 1 is connected with two pipelines, one of which leads to the water scrubber 2, and the other leads to the mixing kettle 5, and both pipelines are equipped with control valves, which can be used to control the opening or closing of the pipeline. During the reaction process, the reaction product in the reactor 1 will be transported to the mixing kettle 5 for further mixing, and then pressed back to the reactor 1 by the pressure pump 6 for further reaction, and a cycle is formed between the reactor 1, the mixing kettle 5 and the pressure pump 6, which can further improve the mixing degree of dodecene, the catalyst and hydrogen sulfide, so as to further improve the reaction efficiency and reaction sufficiency, and help to improve the yield of the finished product. After the reaction is completed, the reaction product in the reactor 1 is no longer transported to the mixing kettle 5, but is transported to the water scrubber 2 for further washing.

[0060] As a further optimization, the equipment for producing tert-dodecyl mercaptan also includes a primary fractionation tower 7, which is provided with a fourth feed port 71, a first discharge port 72 and a second discharge port 73, wherein the first discharge port 72 and the second discharge port 73 are respectively located at the top and the bottom of the primary fractionation tower 7, and the fourth feed port 71 is located between the first discharge port 72 and the second discharge port 73. The fourth feed port 71 is connected to the discharge port of the water washing tower 2, the first discharge port 72 is connected to the first feed port 11, and the second discharge port 73 is connected to the feed port of the distillation tower 3.

[0061] In this embodiment, the crude tert-dodecyl mercaptan output from the water washing tower 2 is divided into two paths, one path leads to the distillation tower 3 for further refining, and the other path leads to the primary separation tower 7 for steam distillation. The steam distillation in the primary separation tower 7 will produce light component dodecene and heavy component crude tert-dodecyl mercaptan, and the light component dodecene will be transported back to the reactor 1 as a raw material to participate in the reaction again, while the heavy component crude tert-dodecyl mercaptan is transported to the distillation tower 3 for further refining. By setting the primary separation tower 7, the raw material dodecene can be reused, the production cost can be effectively reduced, the generation of production waste can be reduced, and it is beneficial to environmental protection.

[0062] In some embodiments, the distillation tower 3 is also provided with a high-pressure vacuum pump, which can control the distillation tower 3 to be in a high vacuum state, so that the distillation tower 3 maintains a low pressure and temperature, which is beneficial to inhibiting the decomposition of tert-dodecyl mercaptan and ensuring the yield of the finished tert-dodecyl mercaptan. At the same time, it can also effectively control the chromaticity of tert-dodecyl mercaptan and ensure the quality of the finished tert-dodecyl mercaptan.

[0063] In this embodiment, the reactor 1 is further provided with a magnetic stirrer 14. The use of the magnetic stirrer 14 can achieve high-speed stirring of the reactants, thereby improving the mixing uniformity of the reactants, effectively improving the reaction efficiency and reaction sufficiency, and further improving the yield and quality of the finished product.

[0064] The equipment for producing tert-dodecyl mercaptan in this embodiment can improve the mixing degree of dodecene, catalyst and hydrogen sulfide by arranging a mixing kettle and a pressure pump, further improve the reaction efficiency and reaction sufficiency, and help to improve the yield of the finished product; by arranging a primary separation tower, the raw material dodecene can be reused, effectively reducing production costs and reducing the generation of production waste; by arranging a high-pressure vacuum pump on the distillation tower 3, the vacuum degree in the distillation tower 3 can be improved, the pressure and temperature in the tower can be reduced, which is conducive to ensuring the yield and quality of the finished product; by arranging a magnetic stirrer, the yield and quality of the finished product can be further improved.

[0065] The above contents are merely examples and illustrations of the structure of the present invention, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, and these obvious replacement forms all belong to the protection scope of the present invention.

Claims

1. A method for producing tert-dodecyl mercaptan, characterized in that: The following steps are involved: Dodecene and the catalyst are mixed evenly, hydrogen sulfide gas is introduced, and the reaction temperature is controlled to be lower than 80°C. When the change range of the reaction temperature is less than 10°C, the reaction is completed. The reaction product is washed with water and distilled to obtain the finished product of tert-dodecyl mercaptan; Wherein, the catalyst is a mixture of aluminum trichloride, carbon tetrachloride and ether.

2. The method for producing tert-dodecyl mercaptan according to claim 1, characterized in that In the catalyst, the mass ratio of aluminum trichloride, carbon tetrachloride and diethyl ether is (1-3):1:(1-3).

3. The method for producing tert-dodecyl mercaptan according to claim 1, characterized in that The mass ratio of the dodecene to the catalyst is 1:0.1-0.3, and the mass ratio of the dodecene to the hydrogen sulfide is 1:0.1-0.

3.

4. The method for producing tert-dodecyl mercaptan according to claim 1, characterized in that The temperature of the dodecene is lower than 10°C, and the temperature of the mixed solution of the dodecene and the catalyst is 10-80°C.

5. The method for producing tert-dodecyl mercaptan according to claim 1, characterized in that The reaction pressure is lower than 0.8 MPa, and the reaction time is 1 to 4 hours.

6. The method for producing tert-dodecyl mercaptan according to claim 1, characterized in that The flow rate of the hydrogen sulfide gas is 3-8 L / min.

7. A device for producing tert-dodecyl mercaptan, used for implementing the method for producing tert-dodecyl mercaptan according to any one of claims 1 to 6, characterized in that: It comprises a reaction kettle (1), a water washing tower (2), a distillation tower (3) and a finished product tank (4) which are connected in sequence; The reactor (1) is provided with a first feed port (11), a second feed port (12) and a third feed port (13), wherein the first feed port (11), the second feed port (12) and the third feed port (13) are used to input the dodecene, the catalyst and the hydrogen sulfide gas respectively.

8. The device for producing tert-dodecyl mercaptan according to claim 7, characterized in that: It also comprises a mixing kettle (5) and a pressure pump (6), wherein the feed port of the mixing kettle (5) is connected to the discharge port of the reaction kettle (1), and the pressure pump (6) is arranged at the discharge port of the mixing kettle (5), and the pressure pump (6) is used to transport the material output from the mixing kettle (5) back to the reaction kettle (1).

9. The device for producing tert-dodecyl mercaptan according to claim 8, characterized in that: The method further comprises a primary separation tower (7), wherein the primary separation tower (7) is provided with a fourth feed port (71), a first discharge port (72) and a second discharge port (73), wherein the first discharge port (72) and the second discharge port (73) are respectively located at the top and the bottom of the primary separation tower (7), and the fourth feed port (71) is located between the first discharge port (72) and the second discharge port (73); The fourth feed port (71) is connected to the discharge port of the water washing tower (2), the first discharge port (72) is connected to the first feed port (11), and the second discharge port (73) is connected to the feed port of the distillation tower (3).

10. The device for producing tert-dodecyl mercaptan according to claim 7, characterized in that: The reaction kettle (1) is provided with a magnetic stirrer (14).

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