Method for catalytically synthesizing sulfenamide rubber vulcanization accelerator by using biological enzyme

Abstract

The invention discloses a method for synthesizing a sulfenamide rubber vulcanization accelerator through biological enzyme catalysis, belongs to the field of biochemical engineering, and aims at providing a green and clean method for preparing the sulfenamide rubber vulcanization accelerator through a biological synthesis technology. Specifically, magnetic microsphere immobilized chloroperoxidase is used as a biocatalyst, hydrogen peroxide is used as an oxidizing agent, and a brand-new green synthesis technology of the accelerant is provided. According to the method, no salt-containing wastewater is discharged, the process is good in environmental protection property, the product quality is high, the magnetic microsphere immobilized chloroperoxidase can be recycled through an external magnetic field, and the use cost of the enzyme is reduced. Biological enzyme catalysis is an emerging green biosynthesis technology, is an important trend of sustainable development, and opens up a brand-new and environment-friendly way for organic synthesis.

Description

Technical Field

[0001] The present invention belongs to the field of biochemistry, specifically to the field of biosynthesis technology of rubber vulcanization accelerators, and particularly relates to a green synthesis method for preparing sulfenamide rubber vulcanization accelerators by biocatalytic enzymes. Background Art

[0003] The chemical industry is one of the pillar industries of the national economy. Currently, the development of the chemical industry faces two major challenges: 1. Modern chemical industry mainly relies on petroleum processing to a large extent. With the increasing shortage of non-renewable resources such as petroleum, research on alternative raw materials should be carried out in a timely manner, and bio-renewable raw materials are an inevitable choice. 2. The inefficiency and environmental problems of traditional chemical industrial processes urgently need to be solved. The industrial chemical processes developed by humans basically rely on chemical catalysts to achieve, usually with low process efficiency, high energy consumption, and being environmentally unfriendly. Replacing chemical catalysts with biocatalysts and fundamentally changing the industrial chemical processes of humans is an important trend in sustainable development.

[0005] With the development of the tire rubber industry and the increasing clarity of the new requirements of the green industry policy, the awareness of environmental protection and safety is increasing day by day. Deeply carrying out clean production work to greenify rubber materials has become the development direction of the industry.

[0006] As one of the rubber auxiliaries, rubber vulcanization accelerators play a crucial role in the rubber vulcanization process. Among them, sulfenamide rubber vulcanization accelerators have become the fastest-growing and most widely used type of vulcanization accelerators due to their excellent anti-scorching performance, safe processing, short vulcanization time, etc. They are suitable for the vulcanization of natural rubber, styrene-butadiene rubber, nitrile rubber, cis-1,4-polybutadiene rubber, isoprene rubber, etc., and are widely used in products such as tires, rubber shoes, rubber hoses, rubber belts, and cables. Their green synthesis technology is currently a research hotspot in the field of rubber science and the rubber auxiliaries industry.

[0007] The preparation method of this type of accelerator generally uses accelerator M (2-mercaptobenzothiazole) and organic amine as raw materials, and is synthesized by a condensation reaction in the presence of an oxidant. According to the types of oxidants, the current domestic and foreign methods for synthesizing accelerators usually include sodium hypochlorite oxidation method, hydrogen peroxide oxidation method, oxygen oxidation method, chlorine oxidation method and other oxidation methods. Among them, the sodium hypochlorite oxidation method is the most important production process in current industry. This method has the advantages of mature process, simple equipment, easy process control, mild reaction conditions, stable product quality, etc. However, this method produces a large amount of high-salt wastewater, causing serious environmental pollution, difficult to treat, and high cost. The oxygen oxidation method has good purity and no salt-containing wastewater, but the catalyst efficiency is low. The problems of poor operation safety and high operation cost in this process limit its industrialization process. The product obtained by the chlorine oxidation method has good quality, but because the chlorine used in this method is a highly toxic gas, its industrial promotion and application have been greatly restricted. The electrolytic oxidation method has problems such as immature technology and low current efficiency, and is still in the laboratory research stage and cannot be carried out on a large scale of industrial production for the time being.

[0008] Hydrogen peroxide is a green, mild and inexpensive oxidant, which is widely used in green oxidation reactions. However, due to the weak oxidation ability of hydrogen peroxide and relatively low yield, there are literature reports on using metal phthalocyanine compounds as catalysts for the synthesis of accelerators, but the yield is low when using metal phthalocyanine catalysts. Therefore, it is very necessary to develop a new process for synthesizing rubber accelerators with simple process, environmental friendliness and green production.

[0009] In the green synthesis technology of rubber vulcanization accelerators, the catalytic synthesis technology using hydrogen peroxide as an oxidant to achieve an environmentally friendly chemical synthesis process has become a research hotspot, but the catalysts are all chemical catalysts. The biosynthetic technology of accelerators using bioenzymes as catalysts has not been reported yet. Enzyme catalysts have high selectivity and catalytic activity, and the reaction conditions are mild. They are a brand-new green and environmentally friendly biocatalyst with broad development prospects. Chloroperoxidase (CPO; EC1.11.1.10), abbreviated as CPO, is a bioactive substance isolated from the marine fungus (Caldariomyces fumago). It is a heme glycoprotein, containing approximately 25%-30% carbohydrate compounds, mainly glucosamine and arabinose. In terms of amino acid composition, aspartic acid, glutamic acid, serine, and proline residues are the main ones, accounting for about 45% of the total amino acids, and 25%-35% are non-proteins; its prosthetic group is ferric (IX) protoporphyrin, and the fifth axial ligand on the iron porphyrin ring is the sulfur atom of cysteine, and CPO uses glutamic acid as the distal acid-base catalytic component. Chloroperoxidase has a unique active site structure different from other heme peroxidases and will be a biocatalyst with broad application prospects. It has the activities of both heme peroxidase and catalase and cytochrome P-450. Due to the high similarity of many of its spectroscopic and chemical properties to cytochrome P-450, CPO not only has the activity of heme peroxidase but also has catalytic properties similar to catalase. It is precisely because CPO has a unique active cavity structure that it is currently considered the enzyme with the richest catalytic activity in the peroxidase family and has a wide range of substrate adaptabilities. Therefore, it has attractive application prospects in modern synthetic chemistry, biotransformation, and the pharmaceutical industry. The literature (Trevisan Vet a1. Angew Chem Int Ed Engl, 2004, 43(31): 4097-4099) reported the use of a microporous silica cage (microcapsule) technology to immobilize CPO and studied the catalytic oxidation reaction of sulfides using H2O2 as an oxidant. The results showed that not only the stability of the enzyme was significantly improved, but also a relatively high enantioselectivity for the formation of the oxidation product sulfoxide was achieved. The literature (Corbett MD, et a1. Bioorgank Chemistry, 1979, 8: 91-95; Doerge DR, Corbett M D. Chem.Res.Toxicol., 1991, 4: 556-560) reported that chloroperoxidase can catalyze the oxidation of aromatic amines to form the corresponding nitroso compounds. CPO, as a hemoglobin-containing enzyme most favorable for the sulfur oxidation reaction due to its high enantioselectivity, can efficiently catalyze the sulfur oxidation reaction of many alkyl phenyl sulfides and heterocyclic sulfides.The synthetic reactions of chloroperoxidase-catalyzed H2O2 oxidation to form C-N, N-O, S-O, and C-O bonds have been reported, but the synthetic reaction to form N-S bonds has not been reported. In particular, the synthesis of sulfenamide rubber vulcanization accelerators catalyzed by chloroperoxidase has not been reported. We directly co-precipitated with carboxymethyl chitosan during the synthesis of magnetic micro-nanoparticles to obtain Fe3O4 micro-nanomagnetic microspheres coated with carboxymethyl chitosan. Then, CPO was cross-linked and immobilized through chemical bonds as a catalyst, and hydrogen peroxide was used as an oxidant to prepare sulfenamide rubber vulcanization accelerators. Summary of the Invention

[0010] The purpose of the present invention is to provide a method for preparing sulfenamide rubber accelerators by a green and clean biosynthetic technology. Specifically, it uses magnetic microsphere-immobilized chloroperoxidase as a biocatalyst and hydrogen peroxide as an oxidant, providing a new synthetic process for sulfenamide rubber vulcanization accelerators. This method is green and environmentally friendly with high product quality. Biocatalytic enzyme is an emerging green biosynthetic method with advantages such as high efficiency, high selectivity, and low enzyme dosage, opening up a new and environmentally friendly way for organic synthesis.

[0011] To achieve the above purpose, the present invention is realized through the following scheme: A method for biocatalytic synthesis of sulfenamide rubber vulcanization accelerators, comprising the following steps: Step 1: First, prepare a biocatalytic enzyme catalyst. The biocatalytic enzyme catalyst refers to magnetic microsphere-immobilized chloroperoxidase. Specifically, it is chloroperoxidase loaded on Fe3O4 micro-nanomagnetic microspheres coated with carboxymethyl chitosan. The preparation method is as follows: (1) Take a certain amount of FeCl2·4H2O (content ≥ 99.0%) and FeCl3·6H2O (content ≥ 99.0%) (with a molar ratio of nFeCl2 to nFeCl3 = 1:2) and dissolve them in a certain amount of distilled water, and then add a carboxymethyl chitosan solution and stir evenly; (2) Add 10% NaOH solution to adjust the pH of the system to 9 - 12, and stir and react at 25 - 70 °C for 10 - 30 minutes; (3) After crystallization at 30 - 60 °C for 2 hours, filter and wash to obtain Fe3O4 micro-nanomagnetic microspheres coated with carboxymethyl chitosan; (4) Take a certain amount of carboxymethyl chitosan-coated Fe3O4 micro-nano magnetic microspheres and disperse them in a certain amount of distilled water, stir and mix well. Add chloroperoxidase solution (activity: 50000 U / ml), stir evenly, then add glutaraldehyde solution (content 25%), adjust to a weakly acidic to neutral environment (pH 5-7), control the temperature at 50-70 °C, react for 30 minutes, filter and wash, and dry in vacuum to obtain chloroperoxidase-loaded carboxymethyl chitosan-coated Fe3O4 micro-nano magnetic microspheres (abbreviation: magnetic microsphere-immobilized chloroperoxidase).

[0012] Step 2: Add a certain mass of accelerator M and a certain volume of water to the reaction flask, start the stirrer, stir and mix evenly, then add organic amine, and stir at room temperature.

[0013] Step 3: Heat the reaction system to a certain temperature, and slowly dropwise add hydrogen peroxide for the first-stage oxidation.

[0014] Step 4: Add magnetic microsphere-immobilized chloroperoxidase, and slowly dropwise add hydrogen peroxide in the second stage from a constant pressure dropping funnel to the above system, control the dropping rate to make the system react slowly and evenly. When the starch-iodide test paper shows a slightly blue color, stop dropping hydrogen peroxide, and continue stirring for 20 minutes.

[0015] Step 5: First, recover magnetic microsphere-immobilized chloroperoxidase through an external magnetic field, then filter and wash the reaction mixture with water, and dry the wet product at a temperature of 60-70 °C to obtain a sulfenamide rubber vulcanization accelerator product.

[0016] Further, in Step 2, the organic amine is any one of cyclohexylamine, dicyclohexylamine, tert-butylamine, morpholine, diethylamine, diisopropylamine, etc.

[0017] Further, in Step 2, the feeding molar ratio is M:organic amine = 1:1.05-2.5, and the mass of accelerator M:the volume of water = 1:3-4.

[0018] Further, in Step 2, after dropping the organic amine, the stirring time is 40-60 min.

[0019] Further, in Step 3, the feeding molar ratio is M:hydrogen peroxide in the first stage = 1:0.7-0.8, and the dropping time is 60-90 min.

[0020] Further, in Step 4, the feeding molar ratio is M:hydrogen peroxide in the second stage = 1:0.8-1.0, and the dropping time is 60-90 min.

[0021] Further, in Step 4, the biocatalyst refers to magnetic microsphere-immobilized chloroperoxidase, and the addition amount is 0.2%-1% of the mass of accelerator M.

[0022] Further, the reaction temperature of the oxidation reaction is 25 to 50 °C, preferably 30 to 45 °C.

[0023] Further, the concentration of hydrogen peroxide is 10% to 30%, and the dropping time is 60 to 90 min.

[0024] Further, in step 5, the magnetic microsphere-immobilized chloroperoxidase is recovered by an external magnetic field first. After the solid-liquid separation of the reaction mixture, the obtained mother liquor is distilled to recover the organic amine for use in the next batch production.

[0025] The beneficial effects of the present invention are as follows: 1. The biological enzyme catalysis technology is adopted to solve the problem of low reaction yield in the current preparation process of sulfenamide rubber vulcanization accelerators. It is a brand-new green synthesis method. This method has no high-salt wastewater discharge, is green and environmentally friendly, has extremely low catalyst consumption and is easy to separate, has high product purity, high reaction efficiency, good selectivity, and high yield.

[0026] 2. The magnetic microsphere-immobilized chloroperoxidase is used as a catalyst, and cross-linking immobilization is controlled under mild conditions to reduce the influence of chemical modification on enzyme activity. The immobilized enzyme enhances the thermal stability, improves the alkaline stability and storage stability of the enzyme. And the enzyme activity loss rate of the immobilized enzyme is less than 15% after 10 cycles of use.

[0027] 3. After the reaction, the magnetic microsphere-immobilized chloroperoxidase can be recovered and reused by an external magnetic field, reducing the use cost of the enzyme.

[0028] 4. Hydrogen peroxide is added in two steps. When hydrogen peroxide is initially oxidized at the front end, the process is safe. In the later stage, the enzyme and the second stage of hydrogen peroxide are added dropwise to control the conversion rate of the reactants, improving the product yield and quality. Specific embodiments

[0029] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention. Example 1:

[0030] This example provides a preparation method of the rubber accelerator CBS of the present invention, specifically as follows: Add 20.97 g of accelerator M (content not less than 97%, 0.125 mol) and 63 ml of water into the reaction flask. After stirring and mixing evenly, add 25.30 g of cyclohexylamine (content 98%, 0.25 mol), stir and mix for 40 minutes, slowly dropwise add 11.54 g of hydrogen peroxide in the first stage (content 28%, 0.095 mol), the dropping time is 1 h, add 0.1 g of magnetic microsphere immobilized chloroperoxidase, and then slowly dropwise add 12.14 g of hydrogen peroxide (content 28%, 0.1 mol) through the dropping funnel. Keep the system temperature at 35 °C, adjust the stirring speed to ensure that the reaction proceeds slowly and evenly. After the reaction is completed, first recover the magnetic microsphere immobilized chloroperoxidase through an external magnetic field, then cool down, filter, and wash. Distill the obtained mother liquor to recover cyclohexylamine, and dry the wet product of accelerator CBS at 60 °C. Obtain 30.3 g of white powdery CBS product, with a yield of 91.70%, an initial melting point of 99.1 °C, and a purity of 99.3% (by HPLC method). Example 2:

[0031] This example provides a preparation method of rubber accelerator NS of the present invention, specifically: Add 20.97 g of accelerator M (content not less than 97%, 0.125 mol) and 73.4 ml of water into the reaction flask. After stirring and mixing evenly, add 23.29 g of tert-butylamine (content 98%, 0.312 mol), stir and mix for 60 minutes, slowly dropwise add 10.69 g of hydrogen peroxide in the first stage (content 28%, 0.088 mol), the dropping time is 1 h, add 0.1 g of magnetic microsphere immobilized chloroperoxidase, and then slowly dropwise add 13.36 g of hydrogen peroxide (content 28%, 0.11 mol) into the reaction system through the dropping funnel. Keep the system temperature at 35 °C, adjust the stirring speed to ensure that the reaction proceeds slowly and evenly. After the reaction is completed, first recover the magnetic microsphere immobilized chloroperoxidase through an external magnetic field, then cool down, filter, and wash. Distill the obtained mother liquor to recover tert-butylamine, and dry the wet product of accelerator NS at 70 °C to constant weight. Obtain 27.68 g of white powdery NS product, with a yield of 92.92%, an initial melting point of 107.0 °C, and a purity of 99.1% (by HPLC method). Example 3:

[0032] This example provides a preparation method of rubber accelerator NOBS of the present invention, specifically: Add 20.97 g of accelerator M (content not less than 95%, 0.125 mol) and 63 ml of water into the reaction flask. After stirring and mixing evenly, add 11.41 g of morpholine (content 99%, 0.131 mol), stir and mix for 40 minutes, slowly dropwise add 28.33 g of hydrogen peroxide in the first stage (content 12%, 0.10 mol), the dropping time is 1.5 h, add 0.2 g of magnetic microsphere immobilized chloroperoxidase, then slowly dropwise add 35.42 g of hydrogen peroxide (content 12%, 0.125 mol) through the dropping funnel, maintain the system temperature at 45 °C, adjust the stirring speed to ensure that the reaction proceeds slowly and evenly. After the reaction is completed, first recover the magnetic microsphere immobilized chloroperoxidase by an external magnetic field, then cool down and filter. Add the crude NOBS product into a 2 - 5% sodium hydroxide solution, stir at 80 - 85 °C for 2 hours, then quickly cool down, filter and wash with water, and vacuum dry at 60 °C. Obtain 29.01 g of NOBS product in the form of light yellow small particles, with a yield of 92.09%, an initial melting point of 80.5 °C, and a purity of 99.0% (HPLC method).

[0033] Comparative Example 1: This example is a comparative example, preparing accelerator CBS without adding magnetic microsphere immobilized chloroperoxidase. Specifically: Add 20.97 g of accelerator M (content not less than 95%, 0.125 mol) and 63 ml of water into the reaction flask. After stirring and mixing evenly, add 25.30 g of cyclohexylamine (content 98%, 0.25 mol), stir and mix for 40 minutes, slowly dropwise add 10.77 g of hydrogen peroxide in the first stage (content 30%, 0.095 mol), the dropping time is 1 h, then slowly dropwise add 11.33 g of hydrogen peroxide (content 30%, 0.1 mol) into the reaction system through the dropping funnel, maintain the system temperature at 35 °C, adjust the stirring speed to ensure that the reaction proceeds slowly and evenly. After the reaction is completed, cool down, filter and wash, recover cyclohexylamine by distilling the obtained liquid, and put the wet accelerator CBS into a preheated oven and dry it to constant weight at 60 °C. Obtain 24.13 g of CBS product in the form of off - white powder, with a yield of 73.3%, an initial melting point of 98.1 °C, and a purity of 97.5% (HPLC method).

[0034] Comparative Example 2: This example is a comparative example, preparing accelerator CBS by adding recycled magnetic microsphere immobilized chloroperoxidase. Specifically: Add 20.97 g of accelerator M (content not less than 95%, 0.125 mol) and 63 ml of water to the reaction flask. After stirring and mixing evenly, add 25.30 g of cyclohexylamine (content 98%, 0.25 mol), stir and mix for 40 minutes, slowly dropwise add 10.77 g of hydrogen peroxide in the first stage (content 30%, 0.095 mol), the dropping time is 1 h, add 0.1 g of recovered magnetic microsphere-immobilized chloroperoxidase, and then slowly drop 11.33 g of hydrogen peroxide (content 30%, 0.1 mol) into the reaction system through a dropping funnel. The temperature of the system is maintained at 35 °C, adjust the stirring speed to ensure that the reaction proceeds slowly and evenly. After the reaction is completed, first recover the magnetic microsphere-immobilized chloroperoxidase through an external magnetic field, then filter and wash. Distill the obtained mother liquor to recover cyclohexylamine, and put the wet product of accelerator CBS into a preheated oven and dry it to constant weight at 60 °C. Obtain 30.14 g of white powdery CBS product, with a yield of 91.20%, an initial melting point of 99.0 °C, and a purity of 99.1% (HPLC method).

[0035] It can be seen from the comparative examples and examples of synthesizing CBS that without adding magnetic microsphere-immobilized chloroperoxidase, the yield is relatively low, the appearance color is grayish white, and the product quality is poor. While adding magnetic microsphere-immobilized chloroperoxidase, the appearance color of the product is white, the yield is high, the melting point is high, and the product quality is good. And the product quality is comparable when adding recovered and newly prepared magnetic microsphere-immobilized chloroperoxidase.

[0036] Finally, it should be noted that for those skilled in the art, obviously the present invention is not limited to the details of the above exemplary embodiments, and without departing from the spirit or basic characteristics of the present invention, the present invention can be implemented in other specific forms. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims should be included within the protection scope of the present invention.

Claims

1. A method for synthesizing sulfenamide rubber vulcanization accelerators by biocatalysis, characterized in that It includes the following steps: Step 1: Add accelerator M and water into a reaction flask, start the stirrer, stir and mix evenly, then dropwise add organic amine, and stir at room temperature; Step 2: Keep the temperature of the reaction system at 25 - 50 °C, and slowly dropwise add hydrogen peroxide in the first stage for a preliminary oxidation reaction; Step 3: Add magnetic microsphere immobilized chloroperoxidase, and slowly dropwise add hydrogen peroxide in the second stage into the above system from a constant pressure dropping funnel, maintain the temperature at 25 - 50 °C, control the dropping rate to make the oxidation reaction proceed slowly and evenly. When the starch - potassium iodide test paper shows a slightly blue color, stop dropping hydrogen peroxide, and continue stirring for 20 minutes; Step 4: After the reaction is completed, first recover the magnetic microsphere immobilized chloroperoxidase through an external magnetic field, then cool down, filter and wash with water, put the wet product into an oven at 60 - 70 °C for drying to obtain a sulfenamide rubber vulcanization accelerator product.

2. The method for synthesizing sulfenamide rubber vulcanization accelerators by biocatalysis according to claim 1, characterized in that For the described magnetic microsphere immobilized chloroperoxidase, its preparation method is as follows: (1) Take FeCl2·4H2O and FeCl3·6H2O, dissolve them in distilled water according to the molar ratio of nFeCl2 to nFeCl3 = 1:2, and then add a carboxymethyl chitosan solution and stir evenly; (2) Add 10% NaOH solution to adjust the pH of the system to 9 - 12, and stir and react at 25 - 70 °C for 10 - 30 minutes; (3) After crystallization at 30 - 60 °C for 2 hours, filter and wash to obtain Fe3O4 micro - nano magnetic microspheres coated with carboxymethyl chitosan; (4) Take the Fe3O4 micro - nano magnetic microspheres coated with carboxymethyl chitosan, disperse them in distilled water and stir and mix, add a chloroperoxidase solution, stir evenly, then add a glutaraldehyde solution, adjust to a weakly acidic to neutral environment, control the temperature at 50 - 70 °C, after reacting for 30 minutes, filter and wash, and vacuum dry at room temperature to obtain chloroperoxidase - loaded carboxymethyl chitosan - coated Fe3O4 micro - nano magnetic microspheres, abbreviated as: magnetic microsphere immobilized chloroperoxidase.

3. The method for biosynthetic preparation of sulfenamide rubber vulcanization accelerator by enzymatic catalysis according to claim 1, characterized in that In the described Step 1, the organic amine is any one of cyclohexylamine, dicyclohexylamine, tert - butylamine, morpholine, diethylamine, and diisopropylamine.

4. The method for biosynthetic production of sulfenamide rubber vulcanization accelerators by enzymatic catalysis according to claim 1, characterized in that In the described Step 1, the feeding molar ratio is M: cyclohexylamine = 1:1.05 - 2.5, and the mass of accelerator M: the volume of water = 1:3 - 4.

5. The method for biosynthetically catalyzing the synthesis of sulfenamide rubber vulcanization accelerators as claimed in claim 1, characterized in that In the described Step 2, the feeding molar ratio is M: hydrogen peroxide in the first stage = 1:0.7 - 0.8, and the dropping time is 60 - 90 min.

6. The method for biosynthetically catalyzing the synthesis of sulfenamide rubber vulcanization accelerators as described in claim 1, characterized in that In the described Step 3, the feeding molar ratio is M: hydrogen peroxide in the second stage = 1:0.8 - 1.0, and the dropping time is 60 - 90 min.

7. The method for biosynthetic preparation of sulfenamide rubber vulcanization accelerators by enzymatic catalysis according to claim 1, characterized in that In the described Step 3, the biocatalyst refers to magnetic microsphere immobilized chloroperoxidase, and the addition amount is 0.2% - 1% of the mass of accelerator M.

8. The method for synthesizing sulfenamide rubber vulcanization accelerators by biocatalysis according to claim 1, characterized in that In Step 2 and Step 3, the reaction temperature of the oxidation reaction is 25 - 50 °C.

9. The method for biosynthetic preparation of sulfenamide rubber vulcanization accelerator by enzymatic catalysis according to claim 1, characterized in that The concentration of the hydrogen peroxide is 10 - 30%, and the dropping time is 60 - 90 min.

10. The method for biosynthetically catalyzing the synthesis of sulfenamide rubber vulcanization accelerators as claimed in claim 1, characterized in that In Step 4, recover the magnetic microsphere immobilized chloroperoxidase through an external magnetic field.