An organic sulfur complexing agent, a preparation method thereof and application thereof as a vulcanizing agent

Abstract

The application discloses an organic sulfur composite agent, a preparation method thereof and application of the organic sulfur composite agent as a vulcanizing agent. The organic sulfur composite agent contains linear organic sulfur and cyclic organic sulfur. The preparation method of the organic sulfur composite agent comprises the following steps: mixing linear low sulfur ether, low-carbon olefin, a sulfur source and an alkaline catalyst, and then performing reaction; and after the reaction is completed, the organic sulfur composite agent is obtained through temperature reduction and separation. The organic sulfur composite agent not only has a simple preparation method and is easy to control, but also contains cyclic organic polysulfide with a long sulfur chain and has a high mass content of the cyclic polysulfide.

Description

Technical Field

[0001] This invention relates to an organic sulfur composite agent, its preparation method, and its application as a sulfurizing agent. More specifically, it relates to an organic sulfur composite agent containing linear and cyclic structures, its preparation method, and its application as a sulfurizing agent. Background Technology

[0002] Organic polysulfides are a class of substances with the general formula RS x -R1 substances, where x is between 2 and 20, R and R1 are alkyl, alkylaryl, aryl or aralkyl functional groups, which can be the same or different, and can be saturated or unsaturated hydrocarbons, or straight-chain, branched or cycloalkanes. Organic polysulfides are often used for the pre-sulfurization treatment of hydrogenation catalysts. Whether it is in-vessel pre-sulfurization or out-of-vessel pre-sulfurization, the activation of the hydrogenation catalyst can only be completed in the presence of a sulfiding agent.

[0003] There are multiple routes for the synthesis of organic polysulfides (OPS). A commonly used method both domestically and internationally involves using thiols and elemental sulfur as raw materials to prepare OPS in the presence of a catalyst. The main development direction of this method is the improvement of traditional catalysts such as amines, alkylamines, alkanolamines, inorganic bases, thiols, and alkoxides. For example, US4876389 uses a catalyst with the general formula RSH·x(C m H 2m The composition of O)·yMOH is used as a catalyst; US5068445 uses an alkaline resin as a catalyst; US6051739 utilizes a traditional alkaline substance and the general formula R2O[CH2CH·(R3)O] nThe combination of SO3M surface-active materials as catalysts improves the yield of the synthesis reaction products and facilitates the separation of the catalyst from the products. US4937385, US6472354, and US6544936 respectively provide methods for preparing organic polysulfides using olefins, sulfur, and hydrogen sulfide as raw materials under different catalyst conditions. The reaction pathway is as follows: first, in the presence of elemental sulfur, hydrogen sulfide reacts with olefins to generate intermediate alkyl thiols. Then, the sulfur molecule undergoes ring-opening upon heating, generating various organic polysulfides with different sulfur atom contents under the presence of a basic catalyst. These methods either use thiols as substrates or generate thiols as intermediates during the reaction. Since most thiols are expensive and toxic compounds with a foul odor, the resulting organic polysulfides have an unpleasant odor due to the dissolution of hydrogen sulfide and unreacted thiols, and exhibit poor stability. US5135670, US5338468, US5849677, and CN200710098327.7 disclose methods for preparing organic polysulfides containing polysulfide crosslinks from olefins and elemental sulfur under different catalysts. These methods are simple, use inexpensive and readily available raw materials, and do not introduce halogens. However, the resulting products contain many impurities, have an unpleasant odor, and have a low sulfur content. US4204969, US5410088, and CN1534019 provide methods for first generating halogen-containing sulfurized olefins from olefins and sulfur halides under different catalysts, followed by dehalogenation to prepare relatively pure polysulfides. These synthetic routes yield products with higher sulfur content under milder conditions, but generate large amounts of wastewater, waste gas (HCl, H2S, etc.), and waste residue (containing NaCl and sulfides), making waste treatment difficult.

[0004] CN103937540A and CN108097333A disclose a sulfiding agent for hydrogenation catalysts and its preparation method. The sulfur content of the sulfiding agent is 40wt%~80wt%, and the sulfiding agent includes linear polysulfides and cyclic sulfides. This method overcomes the problems of high toxicity and high production cost of existing sulfiding agents. However, the proportion of cyclic polysulfides in the sulfiding agent prepared by this method needs to be further increased. The sulfur chain length in cyclic polysulfides is generally less than 2, and 4A molecular sieves need to be added during the preparation process. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides an organic sulfur complex, its preparation method, and its application as a sulfurizing agent. The organic sulfur complex is not only simple and easy to prepare, but also contains cyclic organic polysulfide compounds with long sulfur chains and a high mass content of these cyclic polysulfide compounds.

[0006] An organosulfur complex agent, comprising linear organosulfur and cyclic organosulfur, wherein the general structural formula of the linear organosulfur is as follows: The general structural formula of cyclic organic sulfur is: Wherein R1 and R2 are any one of methyl, ethyl, propyl, isopropyl, n-butyl, and isobutyl; R3 and R4 are any one of methyl, ethyl, and branched ethyl; n is an integer from 1 to 5, preferably 3 or 4; m is an integer from 1 to 6, preferably 3 or 4.

[0007] In the organic sulfur composite agent of the present invention, the sulfur content of the organic sulfur composite agent is more than 50 wt%, preferably 55 wt%-75 wt%, and the mass content of cyclic organic sulfur in the organic sulfur composite is higher than 10 wt%, preferably 12 wt%-25 wt%, and more preferably 15 wt%-20 wt%.

[0008] The present invention relates to an organosulfur compound agent, wherein the trisulfide and tetrasulfide constitute 65wt%-90wt% of the total mass of the compound agent, based on its weight.

[0009] The present invention relates to an organic sulfur complex, wherein the organic sulfur complex comprises, by weight, trisulfide and tetrasulfide in the cyclic organic sulfur comprising 75wt%-95wt% of the mass.

[0010] A method for preparing an organosulfur composite agent, the method comprising: mixing a linear low-sulfur ether, a low-carbon olefin, a sulfur source, and an alkaline catalyst and reacting them; and after the reaction is completed, cooling and separation are performed to obtain the organosulfur composite agent.

[0011] According to the method of the present invention, the linear low-sulfur ether is a linear monosulfide and / or a linear disulfide, the mass ratio of linear monosulfide to linear disulfide is 1:2 to 1:20, preferably 1:5 to 1:10, and the amount of linear low-sulfur ether added is 3-15% of the mass of sulfur, preferably 5%-10%.

[0012] According to the method of the present invention, the sulfur source is sulfur, which is a solid at room temperature and exists in the form of S8. The sulfur can be a commercially available product or can be prepared according to existing technology. There are no strict limitations on the purity of the sulfur, and the sulfur may contain appropriate amounts of impurities.

[0013] According to the method of the present invention, the low-carbon olefin is a low-carbon olefin of C2-C4 olefins. The olefin can be a pure olefin or a mixed olefin. The pure olefin can be any one of ethylene, propylene, 1-butene, 2-butene, and isobutene, preferably propylene. The mixed olefin can be any mixture of the above-mentioned pure olefins, or it can be one or more of liquefied petroleum gas, pre-ether C4, and post-ether C4 that mainly contain mixed olefins.

[0014] According to the method of the present invention, the alkaline catalyst comprises an organic base and / or an inorganic base. The organic base includes methylamine, urea, ethylamine, ethanolamine, ethylenediamine, dimethylamine, trimethylamine, diethylamine, triethylamine, propylamine, isopropylamine, 1,3-propanediamine, 1,2-propanediamine, tripropylamine, triethanolamine, butylamine, isobutylamine, tert-butylamine, hexylamine, octylamine, diethylenetriamine, triethylenetetramine, and tetraethylenepentamine; preferably, one or more of dimethylamine, trimethylamine, diethylamine, triethylamine, propylamine, isopropylamine, 1,3-propanediamine, 1,2-propanediamine, tripropylamine, and triethanolamine are used. The inorganic base is one or more of potassium tert-butoxide, sodium methoxide, potassium methoxide, sodium ethoxide, potassium ethoxide, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, and ammonia water.

[0015] According to the method of the present invention, a reaction is carried out after mixing a linear low-sulfur ether, a low-carbon olefin, a sulfur source, and an alkaline catalyst. The reaction temperature is controlled by heating the material system containing the sulfur source, monitoring the viscosity coefficient of the material system, and recording the temperature of the material system as T when the viscosity coefficient of the material system changes from gradually decreasing to increasing. The temperature of the material system is controlled to be 0-15°C higher than T, preferably 4-12°C higher.

[0016] According to the method of the present invention, the alkaline catalyst and the linear low-sulfur ether are added to the material system at least before the viscosity coefficient of the material system changes from gradually decreasing to increasing. They can be added before the material system is heated or during the heating process of the material system.

[0017] According to the method of the present invention, the low-carbon olefin compound can be added to the material system at once, or added intermittently multiple times, or added continuously during the reaction.

[0018] According to the method of the present invention, a linear low-sulfur ether, a low-carbon olefin, a sulfur source, and an alkaline catalyst are added to the reaction system in one step.

[0019] According to the method of the present invention, the mass ratio of the alkaline catalyst to the sulfur source is 0.005 to 0.15, preferably 0.01 to 0.1.

[0020] According to the method of the present invention, the molar ratio of the low-carbon olefin to the sulfur element is 1:1 to 1:8, preferably 1:2 to 1:6.

[0021] According to the method of the present invention, the specific viscosity measured when the viscosity coefficient of the material system gradually changes from decreasing to increasing will vary depending on the material system. Generally, when the viscosity is 5-50 Pa·s, it is preferably 10-40 Pa·s.

[0022] According to the method of the present invention, the heating rate is not particularly limited, but in order to facilitate monitoring of the change in viscosity of the system, the heating rate is generally 0.5-5℃ / min, preferably 1-3℃ / min.

[0023] According to the method of the present invention, the gas phase composition of the reaction system is monitored during the reaction process. When the volume content of hydrogen sulfide in the gas phase composition reaches 1-5%, preferably 2-3%, the reaction is stopped, and the sulfiding agent is obtained by separation after cooling.

[0024] This invention provides a non-limiting method for preparing a vulcanizing agent, the method comprising the following steps:

[0025] (1) Mix the linear low-sulfur ether, sulfur source, organic base and / or inorganic base and put them into the reaction vessel; then replace the air with inert gas and directly fill the required low-carbon olefin or replace the nitrogen with low-carbon olefin and fill the required low-carbon olefin. Heat the material system containing sulfur source, organic base and / or inorganic base and low-carbon olefin to liquefy the sulfur element.

[0026] (2) Measure the viscosity coefficient of the material system. When the viscosity coefficient of the material system changes from gradually decreasing to increasing, the temperature of the material system at this time is recorded as T. Control the temperature of the material system to be 0-15℃ higher than T, preferably 4-12℃ higher, and continue the reaction for a period of time.

[0027] (3) Monitor the gas phase composition of the reaction system in step (2). When the volume content of hydrogen sulfide in the gas phase composition reaches 1-5%, preferably 2-3%, stop the reaction, cool down and separate to obtain the sulfiding agent.

[0028] According to the method of the present invention, the cooling process in step (3) can adopt conventional cooling methods. The cooled gaseous material can be recycled and reused. The liquid material is separated by flash evaporation or distillation to obtain a sulfur-containing composition. For example, by flash evaporation, generally at 30℃~70℃ and 1000pa~20000pa for 1~2h.

[0029] The above-mentioned organic sulfur composite agent is used as a vulcanizing agent for hydrogenation catalysts, a vulcanizing agent for rubber, and a scorching inhibitor.

[0030] The length of the sulfur chain in organic polysulfides (OPS) is a key factor determining their sulfur content and properties, and the ratio of straight-chain to cyclic OPS significantly influences their sulfidation properties. Taking OPS as a sulfiding agent in hydrogenation catalysts as an example, the different decomposition temperatures of OPS and cyclic OPS can be utilized to achieve sustained and slow sulfidation of the catalyst, suppressing the adverse effects of concentrated sulfidation exothermics on the active metal of the hydrogenation catalyst. However, preparing long-chain OPS is quite difficult.

[0031] Based on years of in-depth research on the preparation of organic polysulfides, the inventors discovered that there are two main reasons: First, the generation of sulfur free radicals during the reaction stage. Long-chain free radicals with more than two sulfur atoms are unstable and easily further decompose, resulting in a low content of long-chain sulfur free radicals in the reaction system. Second, in the later stage of the reaction, the reaction equilibrium is affected by factors such as reaction temperature and the concentration of each material, and the generated long-chain organic polysulfides are further decomposed.

[0032] Guided by the above theory, the inventors added straight-chain monosulfides and straight-chain disulfides with low sulfur content to the system. By using chemical equilibrium raw materials, the reaction phase was promoted in the direction of long-chain organic sulfur, which significantly increased the mass content of long-chain organic sulfur.

[0033] Furthermore, the reaction process is precisely controlled. The inventors innovatively propose controlling the reaction temperature by monitoring the viscosity of the material system, enhancing the concentration of sulfur trioxide and higher free radicals during the reaction to promote the formation of long-chain organic polysulfides, and controlling the termination time by controlling the hydrogen sulfide content in the gaseous products to prevent the decomposition of long-chain organic polysulfides. The inventors were surprised to find that through these control methods, not only was the sulfur content in the organic polysulfides significantly increased, but the proportion of cyclic compounds also increased significantly, and cyclic trisulfides and cyclic tetrasulfides were discovered in the organic polysulfides. Detailed Implementation

[0034] The effects and functions of the method of the present invention are further illustrated below with reference to embodiments and comparative examples, but these embodiments do not constitute a limitation of the present invention. Unless otherwise specified, all percentages (%) in the context of the present invention refer to mass percentages. In the method of the present invention, the composition and sulfur content of the prepared organic polysulfide are determined by GC-MAS. The reaction equipment in the method of the present invention is a reaction vessel, which may be configured as needed with a stirring device, a heat exchange device (heating or deheating), a viscosity measuring device, a pressure measuring device, a temperature measuring device, etc.

[0035] Example 1

[0036] (1) First, 220g of elemental sulfur, 2.2g of dimethylamine, 11g of ethyl sulfide and ethyl disulfide mixture (mass ratio of 1:5) are added to the reactor in sequence; then, after replacing the air with nitrogen gas, ethylene is introduced. The molar ratio of the introduced ethylene to elemental sulfur is 1:2. The material system is heated at a rate of 1℃ / min.

[0037] (2) Measure the viscosity coefficient of the material system. When the viscosity coefficient of the material system changes from gradually decreasing to increasing, the viscosity is 10 Pa·s at the lowest point and the temperature is 159℃. Control the reaction temperature not to exceed 170℃ and continue the reaction for a period of time. During the continuous reaction, detect the gas phase composition in the material system. When the volume content of hydrogen sulfide in the gas phase reaches 2wt%, stop the reaction.

[0038] (3) After the reaction in step (2) is completed, the temperature is lowered. The cooled gaseous material can be recovered and reused. The liquid material contains sulfur and is flash-evaporated at 30℃ and 20000pa for 1 hour. The analysis results of the obtained vulcanizing agent product are shown in Table 1.

[0039] Example 2

[0040] (1) First, 220g of elemental sulfur, 22g of triethanolamine, and 22g of a mixture of propyl sulfide and propyl disulfide (mass ratio 1:10) are added sequentially to the reactor; then, after replacing the air with nitrogen gas, propylene is introduced, with a molar ratio of propylene to elemental sulfur of 1:6. The material system is heated at a rate of 3℃ / min.

[0041] (2) Measure the viscosity coefficient of the material system. When the viscosity coefficient of the material system changes from gradually decreasing to increasing, the viscosity is at its lowest point of 40 Pa·s, and the temperature is 163℃. Control the reaction temperature not to exceed 167℃ and continue the reaction for a period of time. During the continuous reaction, detect the gas phase composition of the material system. When the volume content of hydrogen sulfide in the gas phase reaches 3%, stop the reaction.

[0042] (3) After the reaction is completed, the temperature is lowered. The cooled gaseous material can be recovered and reused. The liquid material containing sulfur is flash-evaporated at 70℃ and 1000pa for 2 hours. The analysis results of the obtained vulcanizing agent product are shown in Table 1.

[0043] Example 3

[0044] (1) First, 220g of elemental sulfur, 11g of tripropylamine, 15g of a mixture of isobutyl sulfide and isobutyl disulfide (mass ratio 1:7) are added sequentially to the reactor; then, after replacing the air with nitrogen gas, isobutylene is introduced, with a molar ratio of isobutylene to elemental sulfur of 1:4. The material system is heated at a rate of 2℃ / min.

[0045] (2) Measure the viscosity coefficient of the material system. When the viscosity coefficient of the material system changes from gradually decreasing to increasing, the viscosity is at its lowest point of 30 Pa·s. The temperature is 160℃. Control the reaction temperature not to exceed 169℃ and continue the reaction for a period of time. During the continuous reaction, detect the gas phase composition of the material system. When the volume content of hydrogen sulfide in the gas phase reaches 2.5%, stop the reaction.

[0046] (3) After the reaction is completed, the temperature is lowered. The cooled gaseous material can be recovered and reused. The liquid material contains sulfur and is flash-evaporated at 50℃ and 10000pa for 1.5h. The analysis results of the obtained vulcanizing agent product are shown in Table 1.

[0047] Example 4

[0048] (1) First, 220g of elemental sulfur, 4g of trimethylamine, 5g of diethylamine, and 15g of a mixture of propyl sulfide and isobutyl disulfide (mass ratio 1:7) were added sequentially to the reactor. Then, the air was replaced with nitrogen gas, and a mixture of propylene and isobutylene (molar ratio of propylene to isobutylene 1:2) was introduced. The molar ratio of propylene and isobutylene to elemental sulfur was 1:4. The material system was heated at a rate of 2℃ / min.

[0049] (2) Measure the viscosity coefficient of the material system. When the viscosity coefficient of the material system changes from gradually decreasing to increasing, the viscosity is at its lowest point of 30 Pa·s. The temperature is 160℃. Control the reaction temperature not to exceed 169℃ and continue the reaction for a period of time. During the continuous reaction, detect the gas phase composition of the material system. When the volume content of hydrogen sulfide in the gas phase reaches 2.5%, stop the reaction.

[0050] (3) After the reaction is completed, the temperature is lowered. The cooled gaseous material can be recovered and reused. The liquid material contains sulfur and is flash-evaporated at 50℃ and 10000pa for 1.5h. The analysis results of the obtained vulcanizing agent product are shown in Table 1.

[0051] Example 5

[0052] (1) First, 220g of elemental sulfur, 4g of triethylamine, 4g of propylamine, and 15g of a mixture of n-butyl sulfide and n-butyl disulfide (mass ratio 1:7) were added sequentially to the reactor. Then, after replacing the air with nitrogen gas, 1-butene was introduced, with a molar ratio of 1-butene to elemental sulfur of 1:3. The material system was heated at a rate of 2℃ / min.

[0053] (2) Measure the viscosity coefficient of the material system. When the viscosity coefficient of the material system changes from gradually decreasing to increasing, the viscosity reaches its lowest point at 30 Pa·s. At this time, the temperature is 161℃. Control the reaction temperature not to exceed 170℃. After the system temperature stabilizes, continue the reaction for a period of time. During the continuous reaction, detect the gas phase composition of the material system. When the volume content of hydrogen sulfide in the gas phase reaches 2.5%, stop the reaction.

[0054] (3) After the reaction is completed, the temperature is lowered. The cooled gaseous material can be recovered and reused. The liquid material contains sulfur and is flash-evaporated at 50℃ and 10000pa for 1.5h. The analysis results of the obtained vulcanizing agent product are shown in Table 1.

[0055] Example 6

[0056] (1) First, 220g of elemental sulfur, 4g of isopropylamine, 4g of 1,3-propanediamine, and 15g of a mixture of isobutyl sulfide and isobutyl disulfide (mass ratio 1:7) are added sequentially to the reactor; then, after replacing the air with nitrogen gas, pre-ether C4 is introduced, with the molar ratio of pre-ether C4 to elemental sulfur being 1:3. The material system is heated at a rate of 2℃ / min.

[0057] (2) Measure the viscosity coefficient of the material system. When the viscosity coefficient of the material system changes from gradually decreasing to increasing, the viscosity reaches its lowest point at 30 Pa·s. At this time, the temperature is 158℃. Control the reaction temperature not to exceed 167℃ and continue the reaction for a period of time. During the continuous reaction, detect the gas phase composition of the material system. When the volume content of hydrogen sulfide in the gas phase reaches 2.5%, stop the reaction.

[0058] (3) After the reaction is completed, the temperature is lowered. The cooled gaseous material can be recovered and reused. The liquid material contains sulfur and is flash-evaporated at 50℃ and 10000pa for 1.5h. The analysis results of the obtained vulcanizing agent product are shown in Table 1.

[0059] Example 7

[0060] (1) First, 220g of elemental sulfur, 4g of isopropylamine, 4g of 1,3-propanediamine, and 15g of a mixture of isobutyl sulfide and isobutyl disulfide (mass ratio 1:7) were added sequentially to the reactor. Then, after replacing the air with nitrogen gas, etherified C4 was introduced, with the molar ratio of etherified C4 to elemental sulfur being 1:3. The material system was heated at a rate of 2℃ / min.

[0061] (2) Measure the viscosity coefficient of the material system. When the viscosity coefficient of the material system changes from gradually decreasing to increasing, the viscosity reaches its lowest point at 30 Pa·s. The temperature is 160 degrees Celsius. Control the reaction temperature not to exceed 169 degrees Celsius. After the system temperature stabilizes, continue the reaction for a period of time. During the continuous reaction, detect the gas phase composition of the material system. When the volume content of hydrogen sulfide in the gas phase reaches 2.5%, stop the reaction.

[0062] (3) After the reaction is completed, the temperature is lowered. The cooled gaseous material can be recovered and reused. The liquid material contains sulfur and is flash-evaporated at 50℃ and 10000pa for 1.5h. The analysis results of the obtained vulcanizing agent product are shown in Table 1.

[0063] Example 8

[0064] (1) First, 220g of elemental sulfur, 4g of tripropylamine, 4g of 1,2-propanediamine and 15g of a mixture of propyl sulfide and propyl disulfide (mass ratio of 1:7) are added to the reactor in sequence; then, after replacing the air with nitrogen gas, propylene is introduced, and the molar ratio of propylene to elemental sulfur is 1:3. The material system is heated at a heating rate of 2℃ / min.

[0065] (2) Measure the viscosity coefficient of the material system. When the viscosity coefficient of the material system changes from gradually decreasing to increasing, the viscosity reaches its lowest point at 30 Pa·s. At this time, the temperature is 160℃. Control the reaction temperature not to exceed 168℃. After the system temperature stabilizes, continue the reaction for a period of time. During the continuous reaction, detect the gas phase composition of the material system. When the volume content of hydrogen sulfide in the gas phase reaches 2.5%, stop the reaction.

[0066] (3) After the reaction is completed, the temperature is lowered. The cooled gaseous material can be recovered and reused. The liquid material contains sulfur and is flash-evaporated at 50℃ and 10000pa for 1.5h. The analysis results of the obtained vulcanizing agent product are shown in Table 1.

[0067] Example 9

[0068] (1) First, 220g of elemental sulfur, 4g of sodium ethoxide, 4g of sodium carbonate, and 15g of a mixture of propyl sulfide and propyl disulfide (mass ratio 1:7) were added sequentially to the reactor. Then, after replacing the air with nitrogen gas, propylene was introduced, with a molar ratio of propylene to elemental sulfur of 1:3. The material system was heated at a rate of 2℃ / min.

[0069] (2) Measure the viscosity coefficient of the material system. When the viscosity coefficient of the material system changes from gradually decreasing to increasing, the viscosity is at its lowest point of 30 Pa·s, and the temperature is 162℃. Control the reaction temperature not to exceed 171℃ and continue the reaction for a period of time. During the continuous reaction, detect the gas phase composition of the material system. When the volume content of hydrogen sulfide in the gas phase reaches 2.5%, stop the reaction.

[0070] (3) After the reaction is completed, the temperature is lowered. The cooled gaseous material can be recovered and reused. The liquid material contains sulfur and is flash-evaporated at 50℃ and 10000pa for 1.5h. The analysis results of the obtained vulcanizing agent product are shown in Table 1.

[0071] Example 10

[0072] (1) First, 220g of elemental sulfur, 4g of potassium ethoxide, 4g of potassium carbonate and 15g of a mixture of propyl sulfide and propyl disulfide (mass ratio 1:7) are added sequentially to the reactor; then, after replacing the air with nitrogen gas, propylene is introduced, with the molar ratio of propylene to elemental sulfur being 1:3. The material system is heated at a rate of 2℃ / min.

[0073] (2) Measure the viscosity coefficient of the material system. When the viscosity coefficient of the material system changes from gradually decreasing to increasing, the viscosity reaches its lowest point at 30 Pa·s. At this time, the temperature is 162℃. Control the reaction temperature not to exceed 168℃ and continue the reaction for a period of time. During the continuous reaction, detect the gas phase composition in the material system. When the volume content of hydrogen sulfide in the gas phase reaches 2.5%, stop the reaction.

[0074] (3) After the reaction is completed, the temperature is lowered. The cooled gaseous material can be recovered and reused. The liquid material contains sulfur and is flash-evaporated at 50℃ and 10000pa for 1.5h. The analysis results of the obtained vulcanizing agent product are shown in Table 1.

[0075] Table 1. Analysis Results of Vulcanizing Agent Products

[0076]

Claims

1. A method for preparing an organic sulfur complexing agent, characterized by: The method comprises: mixing linear low-sulfur ether, low-carbon olefin, sulfur source and alkaline catalyst to perform reaction, and obtaining organic sulfur complexing agent through cooling and separation after the reaction is completed; the linear low-sulfur ether is linear monosulfide and / or linear disulfide; the low-carbon olefin is pure olefin, and the pure olefin is any one of ethylene, propylene and 1-butene; the organic sulfur complexing agent contains linear organic sulfur and cyclic organic sulfur, wherein the structural general formula of the linear organic sulfur is , and the structural general formula of the cyclic organic sulfur is ; wherein R1 and R2 are any one of ethyl, propyl and n-butyl; R3 and R4 are any one of methylene, methyl-substituted methylene and ethyl-substituted methylene; n is an integer of 1-5; m is an integer of 1-6; and the mass of tri-sulfide and tetra-sulfide in the organic sulfur complexing agent accounts for 65wt%-90wt% based on the weight of the organic sulfur complexing agent.

2. The method of claim 1, wherein: The organic sulfur complexing agent has n=3 or 4, and m=3 or 4.

3. The method of claim 1, wherein: The organic sulfur complexing agent has a sulfur content of 50wt% or more, and the mass content of the cyclic organic sulfur in the organic sulfur complexing agent is higher than 10wt%.

4. The method of claim 3, wherein: The organic sulfur complexing agent has a sulfur content of 55wt%-75wt%, and the mass content of the cyclic organic sulfur in the organic sulfur complexing agent is 12wt%-25wt%.

5. The method of claim 4, wherein: The mass content of the cyclic organic sulfur in the organic sulfur complexing agent is 15wt%-20wt%.

6. The method of claim 1, wherein: The mass ratio of the linear monosulfide and the linear disulfide is 1:2-1:20, and the addition amount of the linear low-sulfur ether is 3-15% of the sulfur mass.

7. The method of claim 6, wherein: The mass ratio of the linear monosulfide and the linear disulfide is 1:5-1:10, and the addition amount of the linear low-sulfur ether is 5%-10% of the sulfur mass.

8. The method of claim 1, wherein: The sulfur source is sulfur, which is in the form of S8 and is solid at room temperature.

9. The method of claim 1, wherein: The pure olefin is propylene.

10. The method of claim 1, wherein: The basic catalyst comprises an organic base, and the organic base comprises methylamine, urea, ethylamine, ethanolamine, ethylenediamine, dimethylamine, trimethylamine, diethylamine, triethylamine, propylamine, isopropylamine, 1,3-propanediamine, 1,2-propanediamine, tripropylamine, triethanolamine, butylamine, isobutylamine, tert-butylamine, hexylamine, octylamine, diethylene triamine, triethylene tetramine, and tetraethylene pentamine.

11. The method of claim 1, wherein: The basic catalyst is one or more of potassium tert-butoxide, sodium methoxide, potassium methoxide, sodium ethoxide, potassium ethoxide, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, and ammonia.

12. The method of claim 10, wherein: The organic base is one or more of dimethylamine, trimethylamine, diethylamine, triethylamine, propylamine, isopropylamine, 1,3-propanediamine, 1,2-propanediamine, tripropylamine, and triethanolamine.

13. The method of claim 1, wherein: The linear low-sulfur ether, the low-carbon olefin, the sulfur source, and the basic catalyst are mixed and then reacted, and the reaction temperature is controlled by heating the material system containing the sulfur source and monitoring the viscosity coefficient of the material system, when the viscosity coefficient of the material system changes from gradually decreasing to increasing, the temperature of the material system at this time is recorded as T, and the temperature of the material system is controlled to be higher than T by 0-15°C.

14. The method of claim 13, wherein: The linear low-sulfur ether, the low-carbon olefin, the sulfur source, and the basic catalyst are mixed and then reacted, and the reaction temperature is controlled by heating the material system containing the sulfur source and monitoring the viscosity coefficient of the material system, when the viscosity coefficient of the material system changes from gradually decreasing to increasing, the temperature of the material system at this time is recorded as T, and the temperature of the material system is controlled to be higher than T by 4-12°C.

15. The method of claim 13, wherein: The basic catalyst and the linear low-sulfur ether are added to the material system at least before the viscosity coefficient of the material system changes from gradually decreasing to increasing, and are added before the material system is heated or during the heating of the material system.

16. The method of claim 1, wherein: The linear low-sulfur ether, the low-carbon olefin, the sulfur source, and the basic catalyst are added to the reaction system at one time.

17. The method of claim 1, wherein: The mass ratio of the basic catalyst to the sulfur source is 0.005-0.

15.

18. The method of claim 17, wherein: The mass ratio of the basic catalyst to the sulfur source is 0.01-0.

1.

19. The method of claim 1, wherein: The sulfur source is elemental sulfur, and the molar ratio of the low-carbon olefin to the elemental sulfur is 1:1-1:

8.

20. The method of claim 19, wherein: The molar ratio of the low-carbon olefin to the elemental sulfur is 1:2-1:

6.

21. The method of claim 13, wherein: The viscosity of the material system is 5-50 Pa·s when the viscosity coefficient of the material system changes from gradually decreasing to increasing.

22. The method of claim 21, wherein: The viscosity coefficient of the material system is gradually reduced and then increased, and the viscosity is 10-40 Pa·s.

23. The method of claim 13, wherein: The heating rate is 0.5-5 ℃ / min.

24. The method of claim 23, wherein: The heating rate is 1-3 ℃ / min.

25. The method of claim 1, wherein: The gas phase composition of the reaction system is monitored during the reaction, and the reaction is stopped when the volume content of hydrogen sulfide in the gas phase composition reaches 1-5%, and the organic sulfur complexing agent is obtained after separation after cooling.

26. The method of claim 25, wherein: The gas phase composition of the reaction system is monitored during the reaction, and the reaction is stopped when the volume content of hydrogen sulfide in the gas phase composition reaches 2-3%, and the organic sulfur complexing agent is obtained after separation after cooling.

27. The method of claim 1, wherein: The method comprises the following steps: (1) mixing linear low-sulfur ether, sulfur source, organic base and / or inorganic base, and then putting them into a reaction kettle, wherein the sulfur source is elemental sulfur; then performing inert gas replacement to remove air and directly filling the required low-carbon olefin, and heating and warming the material system containing linear low-sulfur ether, sulfur source, organic base and / or inorganic base, and low-carbon olefin to liquefy the elemental sulfur; (2) measuring the viscosity coefficient of the material system, when the viscosity coefficient of the material system is gradually reduced and then increased, the temperature of the material system at this time is recorded as T, and the temperature of the material system is controlled to be higher than T by 0-15 ℃, and the reaction is continued for a period of time; (3) monitoring the gas phase composition of the reaction system in step (2), and stopping the reaction when the volume content of hydrogen sulfide in the gas phase composition reaches 1-5%, and then separating and obtaining the organic sulfur complexing agent after cooling.

28. The method of claim 27, wherein: Step (2) is: measuring the viscosity coefficient of the material system, when the viscosity coefficient of the material system is gradually reduced and then increased, the temperature of the material system at this time is recorded as T, and the temperature of the material system is controlled to be higher than T by 4-12 ℃, and the reaction is continued for a period of time.

29. The method of claim 27, wherein: Step (3) is: monitoring the gas phase composition of the reaction system in step (2), and stopping the reaction when the volume content of hydrogen sulfide in the gas phase composition reaches 2-3%, and then separating and obtaining the organic sulfur complexing agent after cooling.

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