A process for the preparation of dicumyl peroxide

Abstract

The application discloses a preparation method of diisopropylbenzene hydrogen peroxide, which uses diisopropylbenzene as raw material, uses a magnesium phosphate series catalyst and a carbonate as stabilizer simultaneously, and oxidizes to prepare DHP. The method does not need to use peroxide as an initiator, has a faster reaction speed, high conversion rate and selectivity, the catalyst can be used repeatedly, and is suitable for industrial production.

Description

TECHNICAL FIELD

[0001] The application relates to a preparation method of dihydroperoxybenzene, and belongs to the technical field of organic synthesis. BACKGROUND

[0002] Resorcinol is a very important chemical intermediate, which is widely used in rubber products, flame retardants, adhesives, ultraviolet stabilizers and other fields, and has a very broad development prospect.

[0003] The oxidation process of m-diisopropylbenzene is a main process for producing resorcinol at present, dihydroperoxybenzene (DHP) is obtained by oxidizing m-diisopropylbenzene, and resorcinol is obtained by further cracking of the DHP; at present, the preparation method of DHP generally uses m-diisopropylbenzene as raw material, sodium hydroxide as catalyst, and adds peroxide as initiator to obtain the product by air or oxygen oxidation; however, the method has long reaction time, many side reactions and poor reaction selectivity.

[0004] Patent JP2007039435 uses sodium carbonate solution as a catalyst, which improves the corrosion problem of the reactor, but cannot solve the problems of long reaction time and poor selectivity.

[0005] Patent US3666815 uses organic metal complexes such as Co and Cu as reaction catalysts, the preparation of these catalysts is complex, they cannot be recycled, and the cost of industrial production is high; at the same time, the addition of alkali is still needed to maintain the pH value of the system during the reaction.

[0006] Patents US4153635 and US2632774 use alkaline earth metal hydroxides as reaction catalysts, the catalysts have poor activity and cannot effectively shorten the reaction time, the reaction selectivity is poor, and the catalysts are not suitable for industrial production.

[0007] Therefore, how to effectively improve the conversion rate and selectivity of the reaction is a technical problem to be solved in the current DHP preparation method. SUMMARY

[0008] Therefore, the application provides a preparation method of dihydroperoxybenzene (DHP), which uses m-diisopropylbenzene as raw material, uses a magnesium phosphate series catalyst and a carbonate as a stabilizer, and oxidizes to prepare DHP. The method does not need to use peroxide as an initiator, the reaction speed is fast, the generation of dimethylbenzyl alcohol-hydroperoxyisopropylbenzene (HHP) in the reaction process can be effectively avoided, the generation of polymerization heavy components in the oxidation process can be effectively inhibited by the presence of a small amount of phosphate, the conversion rate and selectivity are high, the catalyst can be used repeatedly, and the method is suitable for industrial production.

[0009] To achieve the above object, the technical scheme adopted by the application is as follows:

[0010] The present application provides a preparation method of dihydroperoxybenzene, comprising the following steps:

[0011] The dihydroperoxybenzene is prepared by mixing the m-diisopropylbenzene, the tert-butylbenzene, the magnesium phosphate catalyst and the carbonate stabilizer, and then introducing the oxidant for the oxidation reaction.

[0012] In a preferred embodiment of the present application, the amount of the tert-butylbenzene is 0.3-1 times, preferably 0.5-0.7 times of the mass of the m-diisopropylbenzene.

[0013] In a preferred embodiment of the present application, the magnesium phosphate catalyst is selected from one or more of magnesium phosphate, magnesium hydrogen phosphate trihydrate, anhydrous trimagnesium phosphate, trimagnesium phosphate tetrahydrate, magnesium pyrophosphate and phosphorite, preferably magnesium pyrophosphate;

[0014] Preferably, the amount of the magnesium phosphate catalyst is 2.5-10%, preferably 5-7% of the mass of the m-diisopropylbenzene.

[0015] In a preferred embodiment of the present application, the carbonate stabilizer is selected from one or more of alkaline earth metal carbonates, preferably calcium carbonate, magnesium carbonate and barium carbonate, more preferably calcium carbonate;

[0016] Preferably, the amount of the carbonate stabilizer is 0.1-0.5%, preferably 0.3-0.5% of the mass of the m-diisopropylbenzene.

[0017] In a preferred embodiment of the present application, the oxidant is an oxygen-containing gas, wherein the volume fraction of oxygen is preferably 21-100%, more preferably oxygen or air, further preferably air;

[0018] Preferably, the feeding flow rate of the oxidant is 200-500 mL / min, preferably 300-400 mL / min.

[0019] In a preferred embodiment of the present application, the temperature of the oxidation reaction is 80-100°C, preferably 90-95°C; the time is 10-15 h, preferably 12-13 h.

[0020] The reaction pressure is 0.3-0.7 MPaG, preferably 0.5-0.6 MPaG.

[0021] In a preferred embodiment of the present application, after the completion of the oxidation reaction, the reaction solution is cooled to room temperature, and then the catalyst is recovered by filtration, which can be directly used in the next reaction.

[0022] Compared with the prior art, the technical scheme of the present application has the following beneficial effects:

[0023] The method of the present application adopts a magnesium phosphate catalyst, and the raw material isopropyl can quickly generate free radicals R· and H· (structure as follows), thereby initiating the occurrence of subsequent reactions, the reaction speed is fast, the single-pass conversion rate is high, the oxidation reaction liquid does not need to be repeatedly extracted and used, the subsequent complex treatment process is avoided, the overall selectivity of DHP is high, and the overall production process is simplified; meanwhile, the magnesium phosphate catalyst has a suitable basicity, which effectively avoids the generation of HHP from DHP during the reaction, so that the reaction liquid does not need to be subjected to a secondary oxidation of HHP, which is beneficial to the subsequent production process of resorcinol.

[0024]

[0025] Meanwhile, the presence of a small amount of phosphate introduced by the catalyst can effectively inhibit the generation of polymerized heavy components such as DHP dimers or other peroxide dimers in the oxidation process, reduce the loss in the reaction process, and also avoid the consumption of the catalyst caused by the deposition of heavy components during use; the catalyst can be used repeatedly, has low cost, and is suitable for industrial production.

[0026] The present application also introduces carbonate as an additive during the reaction to stabilize the generated peroxide, reduce the yield loss caused by the decomposition of peroxide, and improve the safety of the reaction.

[0027] In addition, since the present application does not need to add peroxide and alkali as initiators and catalysts during the oxidation reaction, the corrosion of the reactor by alkali is avoided, and the production cost is reduced. DETAILED DESCRIPTION

[0028] The present application will be further described below through specific examples, and the examples described in the present application are only used to illustrate the present application and do not limit the scope of the present application.

[0029] Firstly, the source information of the main raw materials in the examples and comparative examples of the present application is as follows:

[0030] p-cymene, purity > 98%, Wanhua Chemical;

[0031] MgHPO4·3H2O, Mg3(PO4)2, Mg3(PO4)2·4H2O, CaCO3, MgCO3, BaCO3, purchased from Beijing Inokai Technology Co., Ltd.;

[0032] MgPyP2O7, the preparation method is as follows: MgHPO4·3H2O is placed in a muffle furnace, heated from 25℃ to 900℃ at a heating rate of 10℃ / min, and calcined at 900℃ for 6h, and MgPyP2O7 catalyst is obtained after cooling;

[0033] The phosphorite is prepared by placing anhydrous trimagnesium phosphate in a muffle furnace, heating from 25℃ to 900℃ at a heating rate of 10℃ / min, calcining at 900℃ for 6h, and obtaining the phosphorite catalyst after cooling;

[0034] Other raw materials and reagents are commercially available general-purpose chemical reagents unless otherwise specified.

[0035] II. Main analysis methods and instruments used in the examples and comparative examples of the present application:

[0036] Liquid chromatography characterization: Agilent 1260 liquid chromatograph, Sphersorb C18 column (Φ4.6×250mm), UV-visible spectrophotometer Hitachi L7420, chromatography workstation data processing system ChomatoPd C-RIA, stationary phase Zorbax-SIL. Chromatographic conditions: mobile phase is a mixture of methanol / acetonitrile=9 / 1 (v / v), detection temperature is 40℃, flow rate is 1mL / min, wavelength is 254nm. Qualitative and quantitative analysis is performed on the product.

[0037] Example 1

[0038] The steps for preparing dihydroperoxy diisopropylbenzene are as follows:

[0039] Into a 2L reaction kettle, 250.0g of m-diisopropylbenzene, 125g of tert-butylbenzene, 12.5g of magnesium pyrophosphate, and 0.75g of calcium carbonate were added. The reaction system was heated to 90℃, and air was introduced at a speed of 300mL / min. The system was reacted under a constant pressure of 0.5MPa for 12h. The reaction liquid was cooled to room temperature, the catalyst was recovered by filtration, and the liquid part was sampled for liquid phase analysis. The conversion rate of m-diisopropylbenzene was 95.2%, the selectivity of DHP was 90.7%, the selectivity of HHP was 6.1%, and the selectivity of polymerization recombination components and other impurities was 3.2%.

[0040] The recovered catalyst was filtered, and then dihydroperoxy diisopropylbenzene was prepared using the recovered catalyst according to the above method. The results are shown in Table 1:

[0041] Table 1

[0042] Number of runs Conversion % DHP selectivity % HHP selectivity % Polymerization heavies and other impurities selectivity % 2 94.9 91.2 5.9 2.9 5 95.8 90.5 5.7 3.8 10 95.3 90.3 5.5 4.2 20 94.8 91.7 6.0 2.3 30 95.9 91.5 6.2 2.3 50 94.7 91.2 5.8 3.0

[0043] Example 2

[0044] The steps for preparing dihydroperoxy diisopropylbenzene are as follows:

[0045] Into a 2L reactor, 250g of m-diisopropylbenzene, 125g of t-butylbenzene, 6.25g of magnesium pyrophosphate, 0.25g of calcium carbonate were added, the reaction system was heated to 80°C, pure oxygen was bubbled at a rate of 200mL / min, the system was kept at a constant pressure of 0.7MPa for 15h; the reaction liquid was cooled to room temperature, the catalyst was recovered by filtration, the liquid part was sampled for liquid phase analysis, the conversion rate of m-diisopropylbenzene was 97.2%, the selectivity of DHP was 88.7%, the selectivity of HHP was 3.6%, and the selectivity of polymerization heavy components and other impurities was 7.7%.

[0046] Example 3

[0047] The preparation of dihydroperoxy diisopropylbenzene was as follows:

[0048] Into a 2L reactor, 250g of m-diisopropylbenzene, 125g of t-butylbenzene, 25g of magnesium pyrophosphate, 1.25g of calcium carbonate were added, the reaction system was heated to 100°C, air was bubbled at a rate of 500mL / min, the system was kept at a constant pressure of 0.3MPa for 10h; the reaction liquid was cooled to room temperature, the catalyst was recovered by filtration, the liquid part was sampled for liquid phase analysis, the conversion rate of m-diisopropylbenzene was 92.5%, the selectivity of DHP was 90.1%, the selectivity of HHP was 7.5%, and the selectivity of polymerization heavy components and other impurities was 2.4%.

[0049] Example 4

[0050] The preparation of dihydroperoxy diisopropylbenzene was as follows:

[0051] Into a 2L reactor, 250g of m-diisopropylbenzene, 125g of t-butylbenzene, 17.5g of magnesium pyrophosphate, 1g of calcium carbonate were added, the reaction system was heated to 95°C, air was bubbled at a rate of 400mL / min, the system was kept at a constant pressure of 0.6MPa for 13h; the reaction liquid was cooled to room temperature, the catalyst was recovered by filtration, the liquid part was sampled for liquid phase analysis, the conversion rate of m-diisopropylbenzene was 94.8%, the selectivity of DHP was 91.0%, the selectivity of HHP was 5.9%, and the selectivity of polymerization heavy components and other impurities was 3.1%.

[0052] Example 5

[0053] The preparation of dihydroperoxy diisopropylbenzene was as follows:

[0054] Into a 2L reactor, 250g of m-diisopropylbenzene, 125g of t-butylbenzene, 15g of anhydrous trimagnesium phosphate, 1g of barium carbonate were added, the reaction system was heated to 95°C, air was introduced at a speed of 400mL / min, and the system was reacted at a constant pressure of 0.6MPa for 13h. The reaction liquid was cooled to room temperature, the catalyst was recovered by filtration, and the liquid part was sampled for liquid phase analysis. The conversion rate of m-diisopropylbenzene was 92.5%, the selectivity of DHP was 89.6%, the selectivity of HHP was 3.2%, and the selectivity of polymeric heavy components and other impurities was 7.2%.

[0055] Comparative Example 1

[0056] According to the method of Example 1, the only difference is that the catalyst magnesium pyrophosphate is replaced by magnesium sulfate, and other operations and conditions remain unchanged. The conversion rate of m-diisopropylbenzene is 50.0%, the selectivity of DHP is 75.6%, the selectivity of HHP is 3%, and the selectivity of polymeric heavy components and other impurities is 21.4%.

[0057] Comparative Example 2

[0058] According to the method of Example 1, the only difference is that the catalyst magnesium pyrophosphate is replaced by calcium phosphate, and other operations and conditions remain unchanged. The conversion rate of m-diisopropylbenzene is 70.2%, the selectivity of DHP is 70.5%, the selectivity of HHP is 12%, and the selectivity of polymeric heavy components and other impurities is 17.5%.

[0059] Comparative Example 3

[0060] According to the method of Example 1, the only difference is that no calcium carbonate stabilizer is added, and other operations and conditions remain unchanged. The conversion rate of m-diisopropylbenzene is 95.1%, the selectivity of DHP is 70.3%, the selectivity of HHP is 7%, and the selectivity of polymeric heavy components and other impurities is 22.7%.

[0061] Comparative Example 4

[0062] According to the method of Example 1, the only difference is that calcium carbonate is replaced by calcium sulfate, and other operations and conditions remain unchanged. The conversion rate of m-diisopropylbenzene is 94.8%, the selectivity of DHP is 71.2%, the selectivity of HHP is 7.2%, and the selectivity of polymeric heavy components and other impurities is 21.6%.

Claims

1. A method for preparing dicumyl peroxide, characterized in that the steps include... include: Diisopropylbenzene, tert-butylbenzene, magnesium phosphate catalyst and carbonate stabilizer are mixed and then an oxidant is introduced to carry out an oxidation reaction to obtain diisopropylbenzene hydrogen peroxide.

2. The preparation method according to claim 1, characterized in that, The amount of tert-butylbenzene used is 0.3-1 times the mass of m-diisopropylbenzene.

3. The preparation method according to claim 2, characterized in that, The amount of tert-butylbenzene used is 0.5-0.7 times the mass of m-diisopropylbenzene.

4. The preparation method according to claim 1, characterized in that, The magnesium phosphate catalyst is selected from one or more of magnesium phosphate, magnesium hydrogen phosphate trihydrate, anhydrous magnesium triphosphate, magnesium triphosphate tetrahydrate, magnesium pyrophosphate, and magnesium phosphate.

5. The preparation method according to claim 4, characterized in that, The magnesium phosphate catalyst is magnesium pyrophosphate.

6. The preparation method according to claim 1, characterized in that, The amount of the magnesium phosphate catalyst used is 2.5-10% of the mass of m-diisopropylbenzene.

7. The preparation method according to claim 6, characterized in that, The amount of the magnesium phosphate catalyst used is 5-7% of the mass of m-diisopropylbenzene.

8. The preparation method according to claim 1, characterized in that, The carbonate stabilizer is selected from alkaline earth metal carbonates.

9. The preparation method according to claim 8, characterized in that, The carbonate stabilizer is selected from one or more of calcium carbonate, magnesium carbonate, and barium carbonate.

10. The preparation method according to claim 1, characterized in that, The amount of the carbonate stabilizer used is 0.1-0.5% of the mass of m-diisopropylbenzene.

11. The preparation method according to claim 10, characterized in that, The amount of the carbonate stabilizer used is 0.3-0.5% of the mass of m-diisopropylbenzene.

12. The preparation method according to claim 1, characterized in that, The oxidant is an oxygen-containing gas.

13. The preparation method according to claim 12, characterized in that, The oxygen-containing gas has an oxygen volume fraction of 21-100%.

14. The preparation method according to claim 12, characterized in that, The oxidant is oxygen or air.

15. The preparation method according to claim 1, characterized in that, The oxidant feed flow rate is 200-500 mL / min.

16. The preparation method according to claim 15, characterized in that, The oxidant feed flow rate is 300-400 mL / min.

17. The preparation method according to claim 1, characterized in that, The oxidation reaction is carried out at a temperature of 80-100℃ for 10-15 hours.

18. The preparation method according to claim 17, characterized in that, The oxidation reaction is carried out at a temperature of 90-95℃ for 12-13 hours.

19. The preparation method according to claim 1, characterized in that, The oxidation reaction is carried out at a pressure of 0.3-0.7 MPaG.

20. The preparation method according to claim 19, characterized in that, The oxidation reaction is carried out at a pressure of 0.5-0.6 MPaG.

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