A process for the continuous preparation of di(tert-butylperoxyisopropyl)benzene

Abstract

The application provides a method for preparing di(tert-butyl peroxy isopropyl) benzene by a continuous method. The method comprises the following steps: mixing 1,3-diisopropyl benzene with an initiator to obtain mixed solution A, and then introducing the mixed solution A and oxygen into a first microchannel reactor to perform an oxidation reaction, so as to obtain mixed solution B; introducing the mixed solution B, hydrogen and acetic anhydride into a second microchannel reactor to perform a reduction reaction, so as to obtain reaction solution C; adding isononanoic acid into tert-butyl hydroperoxide aqueous solution to obtain mixed solution D; introducing the obtained reaction solution C and the mixed solution D into a third microchannel reactor to perform a condensation reaction, so as to obtain reaction solution E; and performing washing, drying and cooling on the reaction solution E, so as to obtain di(tert-butyl peroxy isopropyl) benzene. The synthesis method is simple and easy to implement, raw materials are cheap and easy to obtain, and the production cost is low; the reaction conversion rate is high, the production efficiency is high, the side reaction is less, the yield and purity of the target product are high, and the product quality is stable.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of synthesis and preparation of di(tert-butylperoxy isopropyl) benzene, and particularly relates to a method for preparing di(tert-butylperoxy isopropyl) benzene by a continuous method. BACKGROUND

[0002] Di(tert-butylperoxy isopropyl) benzene (BIPB for short) is a new type of dialkyl organic peroxide crosslinking agent, and is an upgraded product of dicumyl peroxide (DCP), commonly known as "odorless DCP". Di(tert-butylperoxy isopropyl) benzene can be used as an excellent degradation agent for polypropylene degradation, and can be used to prepare high melt index rheological polypropylene with low molecular weight and narrow molecular weight distribution, and is a very important initiator of controllable rheological polypropylene. At the same time, it can also be used as an initiator for styrene polymerization, and has the characteristics that the molecular weight of the generated polystyrene is larger than that of the thermal initiation polymerization, and the polymerization conversion rate is higher. Furthermore, BIPB is also the most common rubber vulcanizing agent, and has excellent scorch safety, and is usually diluted with silicone oil or other neutral solvents or neutral fillers, and the safe handling temperature is 138 DEG C, and the crosslinking temperature is 175 DEG C. In addition, BIPB can also be used as a crosslinking agent for chlorinated polyethylene (CPE), ethylene-propylene-diene rubber (EPDM), ethylene-vinyl acetate copolymer (such as EVA foaming), and the like. BIPB has no odor in the crosslinking process of the product, has high crosslinking efficiency, and has the characteristics of less dosage (the dosage is only 2 / 3 of that of DCP) under the same crosslinking effect, good heat resistance, low temperature flexibility, and pressure deformation resistance of the product, and the like. With the enhancement of people's environmental protection consciousness and the improvement of life quality, the demand for BIBP will be more and more.

[0003] There are reports about the preparation of di(tert-butylperoxy isopropyl) benzene in the prior art.

[0004] Chinese patent document CN103058908A discloses a method for synthesizing di(tert-butyl peroxy isopropyl) benzene by one step. The synthesis method is to synthesize di(tert-butyl peroxy isopropyl) benzene from tert-butyl hydroperoxide and 2-isopropylphenol (DC) under the catalysis of sodium perchlorate and sulfuric acid. The synthesis method uses a large amount of sulfuric acid as a catalyst for the reaction, so that a large amount of dark red waste sulfuric acid is generated at the same time of synthesizing di(tert-butyl peroxy isopropyl) benzene; this part of waste sulfuric acid cannot be recycled and is difficult to discharge and treat, which is not conducive to environmental protection. At the same time, since the peroxide bond is extremely unstable and is easily decomposed in the presence of strong acid, the use of sulfuric acid will cause a part of tert-butyl hydroperoxide to be acidolysis to form tert-butyl alcohol, thereby reducing the yield of the reaction. In addition, since the peroxide is extremely sensitive to static electricity, the reaction equipment made of enamel material has poor conductivity and is easy to produce static electricity, which is not conducive to safe production, so the reaction equipment preferably selects a stainless steel reactor with good conductivity, and the use of sulfuric acid will cause serious corrosion to the stainless steel production equipment, which is not conducive to industrialized production.

[0005] Chinese patent document CN101544587A discloses a method for preparing α,α'-bis(tert-butyl peroxy) diisopropyl benzene. The synthesis method uses tert-butyl hydroperoxide hydrate and α,α'-dihydroxy-p-diisopropyl benzene as raw materials, and uses heteropoly acid as a catalyst to synthesize α,α'-bis(tert-butyl peroxy) diisopropyl benzene in an organic solvent. The method uses phosphotungsten heteropoly acid as a catalyst for condensation reaction, which has strong hygroscopicity and is inconvenient to store and use. On the other hand, phosphotungsten heteropoly acid is expensive and is used in a large amount, so the raw material cost is high. The used heteropoly acid catalyst adsorbs a large amount of water and peroxide, and the residual peroxide is easy to decompose and explode when heated for dehydration and activation, so it is difficult to recycle and regenerate, thereby being difficult to recycle. In addition, the heteropoly acid has small specific surface area and poor thermal stability, which limits its application in the field of catalysis. Moreover, the yield and purity of the target product need to be improved.

[0006] Chinese patent document CN106588735A discloses a production method of bis(tert-butyl peroxyisopropyl) benzene (BIPB for short). The synthesis method uses di-(2-hydroxyisopropyl) benzene and tert-butyl hydroperoxide aqueous solution as raw materials, aqueous perchloric acid solution as catalyst, toluene as solvent, and performs condensation dehydration reaction under negative pressure. The synthesis method needs to go through a series of processes such as dehydration, nitrogen bubbling, oil-water separation back to the kettle, two alkali washes, two water washes, concentration, nitrogen bubbling, and the like, and the operation steps are relatively complex. Secondly, the synthesis method is not high in safety; this is because the perchloric acid solution is extremely unstable and decomposes at room temperature, and explodes when heated, so the safe storage of the perchloric acid solution requires higher. And because the highest liquid phase temperature in the concentration process is as high as 90℃, and peroxides are relatively sensitive to temperature, they are extremely easy to decompose when the temperature is too high, causing the yield and purity of the product to decrease, and a large amount of heat is released when decomposing, which is not conducive to safe production. Furthermore, the synthesis process produces a large amount of washing wastewater and waste gas containing toluene, pollutes the environment, and increases the burden of wastewater and waste gas treatment, which is not conducive to the implementation of green environmental protection measures. Moreover, the yield and purity of the target product of the method still need to be improved. In summary, the synthesis method is not conducive to large-scale industrial production.

[0007] The raw material 2-isopropylphenol (also known as α,α'-dihydroxy-p-diisopropylbenzene or di-(2-hydroxyisopropyl) benzene) used in the above synthesis method has less market circulation and high price, so the cost of bis(tert-butyl peroxyisopropyl) benzene obtained by this synthesis method is relatively high. In addition, the synthesis process of 2-isopropylphenol is relatively complex, has more side reactions, and has a low conversion rate, so this synthesis method is not conducive to large-scale industrial production. In order to solve the above problems, the present application is proposed. SUMMARY

[0008] In view of the deficiencies of the prior art, the present application provides a method for preparing bis(tert-butyl peroxyisopropyl) benzene by a continuous method. In the method, diisopropylbenzene (DIPB) reacts with oxygen under the action of an initiator in a first microchannel reactor to generate a mixed solution of α,α'-dihydroxy-1,3-diisopropylbenzene (DC), dihydroperoxy diisopropylbenzene (DHP), and 2-hydroxy-2-propyl isopropyl benzene hydroperoxide (HHP); then the mixed solution reacts with hydrogen in a second microchannel reactor to generate DC; finally, DC reacts with tert-butyl hydroperoxide in a third microchannel reactor to generate bis(tert-butyl peroxyisopropyl) benzene (BIPB). The synthesis method of the present application is simple and easy to operate, the raw materials are cheap and easy to obtain, and the production cost is low; the reaction conversion rate is high, the production efficiency is high, the side reactions are few, the yield and purity of the target product are high, the yield is ≥91wt% (calculated based on diisopropylbenzene), and the purity is ≥99wt%, the BIPB product obtained by the present application is stable in quality, and the present application provides a new idea for the synthesis of bis(tert-butyl peroxyisopropyl) benzene.

[0009] The technical scheme of the present application is as follows:

[0010] A method for preparing di(tert-butylperoxy isopropyl) benzene by a continuous method, comprising the following steps:

[0011] (1) mixing 1,3-diisopropylbenzene with an initiator to obtain a mixed solution A, and then simultaneously introducing oxygen into a first micro-channel reactor to perform an oxidation reaction, to obtain a mixed solution B;

[0012] (2) simultaneously introducing the mixed solution B, hydrogen and acetic anhydride into a second micro-channel reactor to perform a reduction reaction, to obtain an α,α'-dihydroxy-1,3-diisopropylbenzene (DC) reaction solution C;

[0013] (3) adding isononanoic acid to a tert-butyl hydroperoxide aqueous solution to obtain a mixed solution D; simultaneously introducing the obtained α,α'-dihydroxy-1,3-diisopropylbenzene (DC) reaction solution C and the mixed solution D into a third micro-channel reactor to perform a condensation reaction, to obtain a di(tert-butylperoxy isopropyl) benzene (BIPB) reaction solution E;

[0014] (4) washing, drying and cooling the obtained di(tert-butylperoxy isopropyl) benzene (BIPB) reaction solution E, to obtain di(tert-butylperoxy isopropyl) benzene (BIPB).

[0015] According to the present application, the micro-channel reactor used is a micro-channel reactor reported in the prior art, also known as a micro-reactor, and the material continuously flows in the micro-channel reactor.

[0016] According to the present application, preferably, the initiator in step (1) is tert-butyl hydroperoxide, and the mass of the initiator is 1-4% of the mass of 1,3-diisopropylbenzene, and further preferably 2%.

[0017] According to the present application, preferably, the molar ratio of 1,3-diisopropylbenzene to oxygen in step (1) is 1:(2.0-2.2), and further preferably 1:2.1.

[0018] According to the present application, preferably, in step (1), in the first micro-channel reactor, the flow rate of the mixed solution A is 3.4-6.8 g / min, and the flow rate of oxygen is 1.31-2.89 g / min; and the molar ratio of the raw materials is controlled within the range of the present application by controlling the flow rate of the material.

[0019] According to the present application, preferably, in step (1), in the first micro-channel reactor, the temperature of the oxidation reaction is 80-95℃, and the residence time of the material in the micro-channel reactor is 15-30 min.

[0020] According to the application, preferably, the molar ratio of hydrogen to 1,3-diisopropylbenzene in step (2) is (0.5-1):1, and more preferably (0.7-0.8):1.

[0021] According to the application, preferably, the mass ratio of acetic anhydride to 1,3-diisopropylbenzene in step (2) is (3-5):1, and more preferably 3.5:1; the addition of acetic anhydride in a specific ratio in the application can consume the water in the reaction system, so as to achieve the effect of shifting the reaction to the positive direction.

[0022] According to the application, preferably, in step (2), the flow rate of the mixed solution B in the second microchannel reactor is 9.30-17.43 g / min, the flow rate of hydrogen is 0.04-0.15 g / min, and the flow rate of acetic anhydride is 23.33-43.75 g / min; and the molar ratio of the raw materials is controlled within the range of the application by controlling the flow rate of the materials.

[0023] According to the application, preferably, in step (2), the temperature of the reduction reaction in the second microchannel reactor is 80-95℃, and the residence time of the materials in the microchannel reactor is 8-15 min.

[0024] According to the application, preferably, the mass fraction of the aqueous tert-butyl hydroperoxide solution in step (3) is 70%; the molar ratio of tert-butyl hydroperoxide to 1,3-diisopropylbenzene is (2.0-2.2):1, and more preferably 2.05:1.

[0025] According to the application, preferably, the mass of isononyl acid in step (3) is 3-6% of the mass of 1,3-diisopropylbenzene, and more preferably 5%.

[0026] According to the application, preferably, in step (3), the flow rate of the α,α’-dihydroxy-1,3-diisopropylbenzene (DC) reaction solution C in the third microchannel reactor is 24.50-32.71 g / min, and the flow rate of the mixed solution D is 8.17-11.95 g / min; and the molar ratio of the raw materials is controlled within the range of the application by controlling the flow rate of the materials.

[0027] According to the application, preferably, in step (3), the temperature of the condensation reaction in the third microchannel reactor is 45-60℃, and the residence time of the materials in the microchannel reactor is 15-20 min.

[0028] According to the application, preferably, in step (4), the washing step is: the obtained reaction solution is washed with water at 45-50 DEG C, and then separated, the obtained organic phase is washed again with 10-15% sodium hydroxide aqueous solution at 45-50 DEG C, and then separated to obtain the organic phase, the mass ratio of the water to 1,3-diisopropylbenzene is 1.5-2.5:1, and the mass ratio of the sodium hydroxide aqueous solution to 1,3-diisopropylbenzene is 0.5-1.5:1; the purpose of the water washing is to remove unreacted acetic anhydride and acetic acid generated by hydrolysis of acetic anhydride, and the purpose of the alkali washing is to remove unreacted tert-butyl hydroperoxide.

[0029] According to the application, preferably, in step (4), the drying is vacuum flash drying, the drying temperature is 45-60 DEG C, the drying pressure is-0.1--0.0MPa, and the drying time is 30-60 min.

[0030] The process route for synthesizing di(tert-butylperoxyisopropyl)benzene according to the application is as follows:

[0031] The reaction in the first micro-channel reactor is as follows:

[0032]

[0033] The reaction in the second micro-channel reactor is as follows:

[0034]

[0035] The reaction in the third micro-channel reactor is as follows:

[0036]

[0037] The methods and devices not described in detail in the application are all prior art, and will not be described again.

[0038] The technical features and beneficial effects of the application are as follows:

[0039] 1. The di(tert-butylperoxyisopropyl)benzene is prepared by using the micro-channel reaction technology according to the application, the production efficiency is high, the reaction conversion rate is high, the side reaction is less, the yield and purity of the target product are high, and the quality of the target product obtained is stable. Meanwhile, due to the special dangerous characteristics of organic peroxide, the temperature sensitivity is high, and in the case of heat accumulation and high temperature, self-decomposition is prone to occur to cause the yield and purity of the product to decrease, the heat generated by the decomposition can cause the temperature to increase sharply to cause a larger range of safety accidents, which is not conducive to the safety production. The temperature control of the reaction process is more accurate by using the micro-channel production technology according to the application, and the local overheating phenomenon is avoided. In addition, the safety of the production by using this production mode is high, the safety hidden danger of the production is less, and the production safety is realized.

[0040] 2、The present application uses tert-butyl hydroperoxide as an initiator for air oxidation, which accelerates the oxidation efficiency and shortens the oxidation process to 15-30 minutes; compared with azo initiators, tert-butyl hydroperoxide has good thermal stability, is safe to use, and is easy to control, and its decomposition products are mainly tert-butyl alcohol and a small amount of acetone, which are non-corrosive and do not require high equipment requirements.

[0041] 3、The present application uses hydrogen as a reducing agent, and its reduction product is water, which improves the reduction efficiency and reduces the discharge of waste salt compared with traditional solid reducing agents such as sodium sulfide and potassium sulfide, and is conducive to clean production.

[0042] 4、The present application uses acetic anhydride as a promoter for the reduction reaction and the condensation reaction, which makes the reaction deviate to the positive direction by reacting with the water generated by the reduction reaction and the condensation reaction, accelerates the efficiency of the reduction reaction and the condensation reaction, and makes the reduction reaction and the condensation reaction more thorough. At the same time, the excess acetic anhydride can also be used as a dehydrating agent for the tert-butyl hydroperoxide solution, which reduces the standing and separation process, shortens the reaction period, saves time cost, and is more simple and easy to operate. Secondly, using acetic anhydride as a dehydrating agent has high dehydration efficiency, low cost, and is safe and non-toxic. In addition, the acetic acid generated by the reaction of acetic anhydride and water can be used as a catalyst for the condensation reaction, which improves the efficiency and conversion rate of the condensation reaction.

[0043] 5、The present application adds iso-nonyl acid during the condensation reaction process, which promotes the oil-water separation effect of the tert-butyl hydroperoxide solution, makes the acetic anhydride consume the water in the reaction system more quickly, and thus promotes the forward progress of the condensation reaction. At the same time, the addition of iso-nonyl acid provides assistance for the subsequent standing and separation of the reaction, making the standing and separation process more efficient.

[0044] 6、The present application can successfully complete the work that cannot be completed in the conventional path by controlling the proportion of the material and the temperature, which shortens the reaction time, has higher selectivity of the target product, higher conversion rate of the reaction, and improves the yield and purity of the target product, and the quality of the obtained product is stable and reliable, which is conducive to large-scale industrial production.

[0045] 7、The synthesis method of the present application has less waste output, short reaction time, high efficiency, cheap and easily available raw materials, and low production cost compared with existing synthesis methods; high reaction conversion rate, less side reaction, high yield and purity of the target product; simple and easy to operate, mild conditions, high safety, and easy to large-scale industrial production. DETAILED DESCRIPTION

[0046] In order to make the objectives, technical solutions and advantages of the present application clearer, the following will be combined with the embodiments of the present application to make a clear and complete description of the technical solutions of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0047] The following will be combined with the embodiments to make a detailed description of the method for preparing di(tert-butylperoxy isopropyl) benzene by a continuous method provided by the present application, and the protection scope of the present application is not limited by the following embodiments.

[0048] Embodiment 1

[0049] A method for preparing di(tert-butylperoxy isopropyl) benzene by a continuous method, comprising the following steps:

[0050] (1) 100 g of 1,3-diisopropylbenzene is mixed with 2 g of tert-butyl hydroperoxide to obtain a mixed solution A, then the mixed solution A is introduced into a first micro-channel reactor at a speed of 5.10 g / min under the adjustment of a flow meter, while oxygen is introduced into the first micro-channel reactor at a speed of 2.07 g / min for oxidation reaction, the reaction temperature is controlled at 85℃, and the residence time is 20 min to obtain a mixed solution B;

[0051] (2) the mixed solution B obtained in step (1) is introduced into a second micro-channel reactor at a speed of 13.94 g / min under the adjustment of a flow meter, while hydrogen and acetic anhydride are introduced into the second micro-channel reactor at speeds of 0.09 g / min and 35.00 g / min respectively, and a reduction reaction occurs in the second micro-channel reactor, the reaction temperature is controlled at 85℃, and the residence time is 10 min to obtain an α,α'-dihydroxy-1,3-diisopropylbenzene (DC) reaction solution C;

[0052] (3) 5.00 g of iso-nonyl acid is added to 162.6 g of a 70% mass fraction tert-butyl hydroperoxide aqueous solution to obtain a mixed solution D; the α,α'-dihydroxy-1,3-diisopropylbenzene (DC) reaction solution C obtained in step (2) is introduced into a third micro-channel reactor at a speed of 24.52 g / min under the adjustment of a flow meter, while the mixed solution D is introduced into the third micro-channel reactor at a speed of 8.38 g / min for condensation reaction, the reaction temperature is controlled at 50℃, and the residence time is 20 min to obtain a di(tert-butylperoxy isopropyl) benzene (BIPB) reaction solution E;

[0053] (4) To the reaction solution E of di(tert-butylperoxy isopropyl)benzene (BIPB) obtained in step (3) was added 200 g of water at 50 °C for washing, and then the organic phase solution was obtained by liquid separation using a separatory funnel;

[0054] (5) The organic phase solution obtained in step (4) was washed with 100 g of 12% sodium hydroxide aqueous solution at 50 °C, and then the organic phase solution was obtained by liquid separation using a separatory funnel;

[0055] (6) The organic phase solution obtained in step (5) was vacuum flash dried at 50 °C and -0.09 MPa for 30 min, and then solidified at room temperature after drying to obtain di(tert-butylperoxy isopropyl)benzene.

[0056] It was detected that the obtained di(tert-butylperoxy isopropyl)benzene was 194.43 g, the purity (HPLC) was 99.41%, the yield (calculated based on 1,3-diisopropylbenzene) was 92.66%, and the appearance was white solid.

[0057] Example 2

[0058] A method for preparing di(tert-butylperoxy isopropyl)benzene by a continuous method, as described in Example 1, except that in step (1), the oxygen was introduced into the first micro-channel reactor at a rate of 1.97 g / min instead of 2.07 g / min; and the other steps and conditions were the same as in Example 1.

[0059] It was detected that the obtained di(tert-butylperoxy isopropyl)benzene was 193.65 g, the purity (HPLC) was 99.38%, the yield (calculated based on 1,3-diisopropylbenzene) was 92.26%, and the appearance was white solid.

[0060] Example 3

[0061] A method for preparing di(tert-butylperoxy isopropyl)benzene by a continuous method, as described in Example 1, except that in step (1), 100 g of 1,3-diisopropylbenzene was mixed with 2 g of tert-butyl hydroperoxide to obtain a mixed solution A, and then the mixed solution A was introduced into the first micro-channel reactor at a rate of 6.80 g / min under the adjustment of a flow meter, while the oxygen was introduced into the first micro-channel reactor at a rate of 2.76 g / min for oxidation reaction, the reaction temperature was controlled at 85 °C, and the residence time was 15 min to obtain a mixed solution B; and the other steps and conditions were the same as in Example 1.

[0062] It was detected that the obtained di(tert-butylperoxy isopropyl)benzene was 193.76 g, the purity (HPLC) was 99.22%, the yield (calculated based on 1,3-diisopropylbenzene) was 92.16%, and the appearance was white solid.

[0063] Example 4

[0064] A continuous process for preparing di(tert-butylperoxyisopropyl)benzene was carried out as described in Example 1 except that in step (2), the hydrogen gas was introduced into the second microchannel reactor at a rate of 0.062 g / min instead of 0.09 g / min; other steps and conditions were the same as in Example 1.

[0065] The obtained di(tert-butylperoxyisopropyl)benzene was 193.11 g in weight, 99.16% in purity (HPLC), 91.80% in yield (calculated from diisopropylbenzene), and white solid in appearance.

[0066] Example 5

[0067] A continuous process for preparing di(tert-butylperoxyisopropyl)benzene was carried out as described in Example 1 except that in step (2), the acetic anhydride was introduced into the second microchannel reactor at a rate of 30.00 g / min instead of 35.00 g / min; other steps and conditions were the same as in Example 1.

[0068] The obtained di(tert-butylperoxyisopropyl)benzene was 193.28 g in weight, 99.29% in purity (HPLC), 92.00% in yield (calculated from diisopropylbenzene), and white solid in appearance.

[0069] Example 6

[0070] A continuous process for preparing di(tert-butylperoxyisopropyl)benzene was carried out as described in Example 1 except that in step (3), 5.00 g of iso-nonyl acid was added to 158.6 g of 70% mass fraction tert-butyl hydroperoxide aqueous solution, and the mixed solution D was introduced into the third microchannel reactor at a rate of 8.18 g / min for condensation reaction; other steps and conditions were the same as in Example 1.

[0071] The obtained di(tert-butylperoxyisopropyl)benzene was 192.69 g in weight, 99.31% in purity (HPLC), 91.74% in yield (calculated from diisopropylbenzene), and white solid in appearance.

[0072] Example 7

[0073] A continuous method for preparing di(tert-butylperoxy isopropyl)benzene, as described in Example 1, except that in step (2), the mixed solution B obtained in step (1) was fed into the second micro-channel reactor at a rate of 17.43 g / min under the regulation of a flow meter, while hydrogen and acetic anhydride were fed into the second micro-channel reactor at a rate of 0.11 g / min and 43.75 g / min, respectively, and the reduction reaction occurred in the second micro-channel reactor, the reaction temperature was controlled at 85°C, and the residence time was 8 min, to obtain the α,α'-dihydroxy-1,3-diisopropylbenzene (DC) reaction solution C; the other steps and conditions were the same as in Example 1.

[0074] It was detected that the obtained di(tert-butylperoxy isopropyl)benzene was 193.31 g, the purity (HPLC) was 99.12%, the yield (calculated based on diisopropylbenzene) was 91.86%, and the appearance was white solid.

[0075] Example 8

[0076] A continuous method for preparing di(tert-butylperoxy isopropyl)benzene, as described in Example 1, except that in step (3), 5.00 g of iso-nonyl acid was added to 162.6 g of 70% mass fraction tert-butyl hydroperoxide aqueous solution to obtain the mixed solution D; the α,α'-dihydroxy-1,3-diisopropylbenzene (DC) reaction solution C obtained in step (2) was fed into the third micro-channel reactor at a rate of 32.69 g / min under the regulation of a flow meter, while the mixed solution D was fed into the third micro-channel reactor at a rate of 11.17 g / min to perform the condensation reaction, the reaction temperature was controlled at 50°C, and the residence time was 15 min, to obtain the di(tert-butylperoxy isopropyl)benzene (BIPB) reaction solution E; the other steps and conditions were the same as in Example 1.

[0077] It was detected that the obtained di(tert-butylperoxy isopropyl)benzene was 193.27 g, the purity (HPLC) was 99.24%, the yield (calculated based on diisopropylbenzene) was 91.95%, and the appearance was white solid.

[0078] Example 9

[0079] A continuous method for preparing di(tert-butylperoxy isopropyl)benzene, as described in Example 1, except that in step (5), 100 g of 12% mass fraction sodium hydroxide solution was replaced by 70 g of 12% mass fraction sodium hydroxide solution for washing; the other steps and conditions were the same as in Example 1.

[0080] It was detected that the obtained di(tert-butylperoxy isopropyl)benzene was 193.36 g, the purity (HPLC) was 99.35%, the yield (calculated based on diisopropylbenzene) was 92.09%, and the appearance was white solid.

[0081] Comparative Example 1

[0082] A continuous process for preparing di(tert-butylperoxy isopropyl)benzene was carried out as described in Example 1 except that in step (1), the oxygen gas was fed into the first microchannel reactor at a rate of 1.48 g / min instead of 2.07 g / min. The other steps and conditions were the same as in Example 1.

[0083] The obtained di(tert-butylperoxy isopropyl)benzene was 182.41 g with a purity (HPLC) of 99.01%, a yield (calculated based on diisopropylbenzene) of 86.58%, and a white solid appearance.

[0084] Comparative Example 2

[0085] A continuous process for preparing di(tert-butylperoxy isopropyl)benzene was carried out as described in Example 1 except that in step (2), the hydrogen gas was fed into the second microchannel reactor at a rate of 0.04 g / min instead of 0.09 g / min. The other steps and conditions were the same as in Example 1.

[0086] The obtained di(tert-butylperoxy isopropyl)benzene was 180.65 g with a purity (HPLC) of 98.27%, a yield (calculated based on diisopropylbenzene) of 85.10%, and a white solid appearance.

[0087] Comparative Example 3

[0088] A continuous process for preparing di(tert-butylperoxy isopropyl)benzene was carried out as described in Example 1 except that in step (3), 5.00 g of iso-nonyl acid was added to the 142.8 mass% tert-butyl hydroperoxide aqueous solution to obtain a mixed solution D, and the mixed solution D was fed into the third microchannel reactor at a rate of 7.39 g / min for condensation. The other steps and conditions were the same as in Example 1.

[0089] The obtained di(tert-butylperoxy isopropyl)benzene was 171.73 g with a purity (HPLC) of 98.69%, a yield (calculated based on diisopropylbenzene) of 81.25%, and a white solid appearance.

[0090] Comparative Example 4

[0091] A continuous process for preparing di(tert-butylperoxy isopropyl)benzene was carried out as described in Example 1 except that in step (1), 2 g of tert-butyl hydroperoxide was replaced by 2 g of azobisisobutyronitrile. The other steps and conditions were the same as in Example 1.

[0092] The obtained di(tert-butylperoxy isopropyl)benzene was 187.72 g, the purity (HPLC) was 98.45%, the yield (calculated based on diisopropylbenzene) was 88.60%, and the appearance was white solid.

[0093] Comparative Example 5

[0094] A method for preparing di(tert-butylperoxy isopropyl)benzene by a continuous method was as described in Example 1, except that in step (2), the acetic anhydride was introduced into the second micro-channel reactor at a speed of 35.00 g / min, which was replaced by introducing the acetic anhydride into the third micro-channel reactor at a speed of 10.29 g / min; and other steps and conditions were the same as in Example 1.

[0095] The obtained di(tert-butylperoxy isopropyl)benzene was 165.47 g, the purity (HPLC) was 85.62%, the yield (calculated based on diisopropylbenzene) was 67.92%, and the appearance was light yellow solid.

[0096] Comparative Example 6

[0097] A method for preparing di(tert-butylperoxy isopropyl)benzene by a continuous method was as described in Example 1, except that in step (3), no iso-nonyl acid was added, and the tert-butyl hydroperoxide aqueous solution was introduced into the third micro-channel reactor at a speed of 8.13 g / min; and other steps and conditions were the same as in Example 1.

[0098] The obtained di(tert-butylperoxy isopropyl)benzene was 186.45 g, the purity (HPLC) was 98.94%, the yield (calculated based on diisopropylbenzene) was 88.44%, and the appearance was white solid.

[0099] The yield and purity data of the products obtained in the examples and the above comparative examples of the present application are shown in Table 1 below:

[0100] Table 1

[0101]

[0102]

[0103] Note: The yield in the table is the yield after purification.

[0104] The above examples are only used to help understand the method of the present application and its core idea. It should be noted that for those skilled in the art, without departing from the principles of the present application, the present application can be improved and modified in several ways, and these improvements and modifications also fall within the scope of protection of the claims of the present application.

Claims

1. A continuous method for preparing di(tert-butylperoxide isopropyl)benzene, characterized in that, The steps include the following: (1) Mix 1,3-diisopropylbenzene with an initiator to obtain mixture A, and then simultaneously introduce it into the first microchannel reactor with oxygen to carry out an oxidation reaction to obtain mixture B; (2) Mixture B, hydrogen and acetic anhydride are simultaneously introduced into the second microchannel reactor to carry out a reduction reaction to obtain α,α'-dihydroxy-1,3-diisopropylbenzene reaction solution C; (3) Add isononanoic acid to the aqueous solution of tert-butyl hydrogen peroxide to obtain a mixture D; simultaneously pass the obtained α,α'-dihydroxy-1,3-diisopropylbenzene reaction solution C and the mixture D into the third microchannel reactor to carry out a condensation reaction to obtain di(tert-butylisopropyl)peroxide reaction solution E. (4) The obtained di(tert-butylperoxyisopropyl)benzene reaction solution E is washed, dried and cooled to obtain di(tert-butylperoxyisopropyl)benzene.

2. The method for preparing di(tert-butylperoxide isopropyl)benzene by continuous method according to claim 1, characterized in that, The initiator mentioned in step (1) is tert-butyl hydroperoxide, and the mass of the initiator is 1-4% of the mass of 1,3-diisopropylbenzene; The molar ratio of 1,3-diisopropylbenzene to oxygen is 1:(2.0~2.2).

3. The method for preparing di(tert-butylperoxide isopropyl)benzene by continuous method according to claim 1, characterized in that, The initiator in step (1) has a mass of 2% of the mass of 1,3-diisopropylbenzene; the molar ratio of 1,3-diisopropylbenzene to oxygen is 1:2.

1.

4. The method for preparing di(tert-butylperoxide isopropyl)benzene by continuous method according to claim 1, characterized in that, In step (1), in the first microchannel reactor, the flow rate of the mixture A is 3.4~6.8 g / min, the flow rate of oxygen is 1.31~2.89 g / min, the temperature of the oxidation reaction is 80~95℃, and the residence time of the material in the microchannel reactor is 15~30 min.

5. The method for preparing di(tert-butylperoxide isopropyl)benzene by continuous method according to claim 1, characterized in that, The molar ratio of hydrogen to 1,3-diisopropylbenzene in step (2) is (0.5~1):

1.

6. The method for preparing di(tert-butylperoxide isopropyl)benzene by continuous method according to claim 1, characterized in that, The molar ratio of hydrogen to 1,3-diisopropylbenzene in step (2) is (0.7~0.8):

1.

7. The method for preparing di(tert-butylperoxide isopropyl)benzene by continuous method according to claim 1, characterized in that, The mass ratio of acetic anhydride to 1,3-diisopropylbenzene in step (2) is (3~5):

1.

8. The method for preparing di(tert-butylperoxide isopropyl)benzene by continuous method according to claim 1, characterized in that, The mass ratio of acetic anhydride to 1,3-diisopropylbenzene in step (2) is 3.5:

1.

9. The method for preparing di(tert-butylperoxide isopropyl)benzene by continuous method according to claim 1, characterized in that, In step (2), in the second microchannel reactor, the flow rate of mixture B is 9.30~17.43 g / min, the flow rate of hydrogen is 0.04~0.15 g / min, and the flow rate of acetic anhydride is 23.33~43.75 g / min; The reduction reaction is carried out at a temperature of 80-95°C, and the residence time of the material in the microchannel reactor is 8-15 min.

10. The method for preparing di(tert-butylperoxide isopropyl)benzene by continuous method according to claim 1, characterized in that, The mass fraction of the tert-butyl hydrogen peroxide aqueous solution in step (3) is 70%; the molar ratio of the tert-butyl hydrogen peroxide to 1,3-diisopropylbenzene is (2.0~2.2):

1.

11. The method for preparing di(tert-butylperoxide isopropyl)benzene by continuous method according to claim 1, characterized in that, The mass of isononanoic acid in step (3) is 3 to 6% of the mass of 1,3-diisopropylbenzene.

12. The method for preparing di(tert-butylperoxide isopropyl)benzene by continuous method according to claim 1, characterized in that, The mass of isononanoic acid in step (3) is 5% of the mass of 1,3-diisopropylbenzene.

13. The method for preparing di(tert-butylperoxide isopropyl)benzene by continuous method according to claim 1, characterized in that, In step (3), in the third microchannel reactor, the flow rate of α,α'-dihydroxy-1,3-diisopropylbenzene reaction solution C is 24.50~32.71 g / min, and the flow rate of mixed solution D is 8.17~11.95 g / min; the temperature of the condensation reaction is 45~60℃, and the residence time of the material in the microchannel reactor is 15~20 min.

14. The method for preparing di(tert-butylperoxide isopropyl)benzene by continuous method according to claim 1, characterized in that, In step (4), the washing step is as follows: water at a temperature of 45~50℃ is added to the obtained reaction solution for washing, and then the liquid is separated. The obtained organic phase is washed again with a sodium hydroxide aqueous solution with a mass fraction of 10~15% at a temperature of 45~50℃, and then the liquid is separated to obtain the organic phase. The mass ratio of water to 1,3-diisopropylbenzene is 1.5~2.5:1, and the mass ratio of sodium hydroxide aqueous solution to 1,3-diisopropylbenzene is 0.5~1.5:

1. The drying process is vacuum flash drying, with a drying temperature of 45~60℃, a drying pressure of -0.1~-0.0MPa, and a drying time of 30~60min.

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