Method and system for preparing epoxy dioxide compound

Abstract

The invention provides a method and a system for preparing an epoxy dioxide compound. The method comprises the following steps: enabling dialkene and cumyl hydroperoxide to be subjected to an oxidation reaction to obtain a mixture flow, enabling the mixture flow to be in contact with a basic catalyst, enabling the cumyl hydroperoxide to be subjected to a decomposition reaction to generate acetophenone and methanol, and then performing post-treatment separation to obtain the epoxy dioxide compound. According to the method, cumyl hydroperoxide is decomposed under the high-temperature alkaline condition, the product is methanol / acetophenone, the risk that epoxide dioxide is subjected to ring-opening hydrolysis to become a by-product is avoided, and the yield of subsequent products is ensured.

Description

Technical Field

[0001] The present invention relates to the field of epoxides, and more particularly to a method and system for preparing diepoxides. Background Art

[0002] Epoxides are a class of compounds with a three-membered ring ether structure. Due to the ring strain, they are much more reactive than ordinary ethers and can undergo ring-opening reactions with various reagents, having a variety of applications. Diepoxides with two epoxy groups in a single molecule, such as dicyclopentadiene dioxide, vinylcyclohexene dioxide, dimethylvinylcyclohexene dioxide, dipentene dioxide, etc., have wide uses and can be used as cross-linking agents, resins, biochemical reagents, plasticizers, etc. For the production of diepoxides, the traditional chlorohydrin method has serious equipment corrosion, a large amount of "three wastes" generation, and serious environmental pollution. Currently, the industrial preparation method mainly uses the peracetic acid method, in which peracetic acid reacts with dienes. It has many operating units, serious equipment corrosion, high requirements for process operation accuracy, low safety, small production scale, and difficult to increase the output.

[0003] In addition, although the method using other organic peroxides as oxidants avoids the problem of equipment corrosion, the process of producing diepoxides also requires the use of excessive organic peroxides to ensure the complete reaction of the raw material diene to obtain diepoxides and avoid the appearance of impurities of incomplete oxidation products. However, in the subsequent separation and purification steps of the material, the material containing organic peroxides needs to undergo a rectification process, which often brings potential safety hazards.

[0004] Patent CN101143919A discloses a method for catalytically synthesizing alicyclic epoxy resins from unsaturated alicyclic compounds, in which hydrogen peroxide solution or alkyl hydroperoxide solution reacts with dienes to synthesize diepoxides. When the peroxide is used insufficiently, this method will cause product loss and difficulty in separating incomplete epoxidation by-products; when the peroxide is in excess, an aqueous solution of sodium salt containing low-valent sulfur is used to consume the peroxide, which may introduce sulfur impurities and requires new treatment and detection units, and the process is complex.

[0005] Patent CN114426549A discloses a method for preparing dicyclopentadiene dioxide (DCPDDO) and 2-phenyl-2-propanol. Cumene hydroperoxide is used to react with dicyclopentadiene, and the unreacted raw materials or incompletely oxidized monocyclopentadiene monoxide are reused after separation steps such as rectification and crystallization. This method has difficulty in controlling incomplete oxidation products when the products are mixed, easily causes loss of the final product, and decreases the yield. Summary of the Invention

[0006] To solve the problems existing in the above synthesis process technology of dioxygenated compounds, the present invention provides a new process means. After the epoxidation reaction unit of cumene hydroperoxide (CHP) and diolefin, a cumene hydroperoxide decomposition reaction unit is introduced. Excess CHP is catalytically decomposed by a basic catalyst under high temperature conditions, and the generated methanol and acetophenone can be removed by distillation. The method of the present invention overcomes the problem of difficult separation of organic peroxides existing in the prior art, ensures the consumption of organic peroxides before the material enters the separation unit, guarantees the safety of the device without adding new logistics, and saves the material and catalyst costs. This method can be used in the synthesis and industrial production of dioxygenated compounds such as dicyclopentadiene dioxide, vinylcyclohexene dioxide, dimethylvinylcyclohexene dioxide, dipentene dioxide, etc.

[0007] One object of the present invention is to provide a method for preparing a dioxygenated compound, which includes contacting a mixed stream obtained by the oxidation reaction of a diolefin and cumene hydroperoxide with a basic catalyst, causing the cumene hydroperoxide to undergo a decomposition reaction to generate acetophenone and methanol, and then performing post-treatment separation to obtain the dioxygenated compound.

[0008] In a preferred embodiment, the method for preparing a dioxygenated compound includes the following steps:

[0009] (1) In the presence of a catalyst, causing a diolefin and cumene hydroperoxide to undergo an oxidation reaction to obtain a mixed stream containing cumene hydroperoxide, α,α-dimethylbenzyl alcohol, dioxygenated compound, and cumene;

[0010] (2) Contacting the mixed stream with a basic catalyst to cause the cumene hydroperoxide to undergo a decomposition reaction to generate acetophenone and methanol;

[0011] (3) Performing post-treatment on the stream obtained in step (2) to separate and obtain the dioxygenated compound.

[0012] In a preferred embodiment, the diolefin is at least one of dicyclopentadiene, vinylcyclohexene, dimethylvinylcyclohexene, and dipentene.

[0013] In a preferred embodiment, cumene hydroperoxide is a CHP oxidation solution containing cumene.

[0014] In step (1) of the present invention, first, a diolefin (dicyclopentadiene, vinylcyclohexene, dimethylvinylcyclohexene, dipentene) is used as a reaction raw material, and cumene hydroperoxide (CHP) is used as an oxidant. A catalytic oxidation reaction occurs when the diolefin, CHP, and the catalyst are in full contact in cumene, generating a main product of epoxidized compound dioxide (dicyclopentadiene dioxide, vinylcyclohexene dioxide, dimethylvinylcyclohexene dioxide, dipentene dioxide). At the same time, the reaction mixture stream after the reaction also includes cumene hydroperoxide, α,α-dimethylbenzyl alcohol (DMBA), cumene, etc.

[0015] The present invention uses CHP to epoxidize the diolefin, and designs an excess of CHP with the aim of epoxidizing both double bonds in the diolefin.

[0016] In a preferred embodiment, in step (1), the molar ratio of cumene hydroperoxide to the diolefin is (2 - 20):1, preferably (2 - 10):1, and more preferably (2 - 3):1.

[0017] In a preferred embodiment, in step (1), the oxidation reaction temperature is 0 - 200 °C and the pressure is 0 - 20 MPa.

[0018] In a more preferred embodiment, in step (1), the oxidation reaction temperature is 50 - 150 °C and the pressure is 0 - 10 MPa.

[0019] In a further preferred embodiment, in step (1), the oxidation reaction temperature is 50 - 130 °C and the pressure is 0.1 - 5.0 MPa.

[0020] In the most preferred embodiment, in step (1), the oxidation reaction temperature is 70 - 130 °C and the pressure is 0.5 - 3.0 MPa.

[0021] In a preferred embodiment, in step (1), the catalyst is selected from at least one of titanium silicalite, titanium silicon mixed oxide, and titanium-supported silica.

[0022] In step (2) of the present invention, the mixture stream containing residual CHP and epoxidized compound dioxide is introduced into a CHP decomposition reactor. CHP undergoes a high-temperature decomposition reaction under the action of a basic catalyst to generate methanol and acetophenone. The mixture stream after the decomposition reaction is a mixture containing epoxidized compound dioxide, methanol, acetophenone, cumene hydroperoxide, α,α-dimethylbenzyl alcohol, and cumene.

[0023] In a preferred embodiment, in step (2), the conditions for the decomposition reaction are: the reaction is carried out at 0 - 300 °C and 0 - 5.0 MPa;

[0024] In a further preferred embodiment, the reaction is carried out at 100 - 300 °C and 0.5 - 3.0 MPa.

[0025] In a still further preferred embodiment, the reaction is carried out at 100 - 200 °C and 1 - 2.0 MPa.

[0026] Among them, the CHP decomposition reaction is carried out in the presence of a catalyst. The catalyst used for the CHP decomposition reaction can be a solid basic catalyst, preferably but not limited to metal oxides, KF supported on porous compounds, metal oxygen-containing salts, and styrene-based anion exchange resins.

[0027] The metal oxide is preferably at least one selected from CaO, MgO, SrO, and BaO.

[0028] In step (3) of the present invention, the mixed stream obtained in step (2) is post-treated to separately obtain epoxide dioxide, methanol, acetophenone, cumene, and DMBA.

[0029] In a preferred embodiment, the post-treatment includes rectification, water washing, and recrystallization.

[0030] In a preferred embodiment, the post-treatment sequentially includes primary rectification, water washing, secondary rectification, tertiary rectification, and recrystallization; wherein the stream obtained in step (2) is subjected to primary rectification to separate methanol, the stream after water washing is subjected to secondary rectification and tertiary rectification to separately obtain a mixture of cumene, acetophenone, and α,α-dimethylbenzyl alcohol and obtain a crude epoxide dioxide stream, and the crude epoxide dioxide stream is subjected to recrystallization to obtain epoxide dioxide.

[0031] In a preferred embodiment, the post-treatment may include the following steps:

[0032] Step 3.1: Introduce the stream obtained in step (2) into the first rectification tower, and separate the light component methanol from the top of the tower;

[0033] Preferably, the top temperature of the first rectification tower is 0 - 150 °C, and the pressure is -0.01 - 11 MPa.

[0034] More preferably, the top temperature of the first rectification tower is 50 - 100 °C, and the pressure is 0 - 5 MPa.

[0035] Step 3.2: Introduce the stream after primary rectification into a water washing kettle, wash the mixed material with deionized water, and after phase separation, the upper layer is an organic phase with metal ions and other substances removed, and the lower layer is a waste liquid containing metal ions, which is discharged from the bottom.

[0036] Preferably, the weight ratio of deionized water to the stream after the first rectification is (0.001 - 15):100.

[0037] Step 3.3: Introduce the upper-layer stream of the water-washing kettle into the second rectification column. Cumene is obtained at the top of the column, and a mixed stream containing acetophenone, α,α-dimethylbenzyl alcohol, and dioxirane is obtained at the bottom of the column.

[0038] Preferably, the top temperature of the second rectification column is 50 - 140 °C, and the pressure is -0.01 - 0.10 MPa.

[0039] More preferably, the top temperature of the second rectification column is 60 - 120 °C, and the pressure is 0 - 0.08 MPa.

[0040] Step 3.4: Introduce the mixed stream of the second rectification column into the third rectification column. A mixed stream of acetophenone and most of the α,α-dimethylbenzyl alcohol is obtained at the top of the column, and a crude dioxirane stream containing dioxirane and a small amount of α,α-dimethylbenzyl alcohol is obtained at the bottom of the column.

[0041] Preferably, the top temperature of the third rectification column is 60 - 120 °C, and the pressure is -0.06 - 0.10 MPa.

[0042] More preferably, the top temperature of the third rectification column is 70 - 110 °C, and the pressure is 0 - 0.08 MPa.

[0043] In step (4) of the present invention, the crude dioxirane stream is recrystallized to obtain a refined dioxirane product.

[0044] In a preferred embodiment, the recrystallization is preferably carried out in a crystallization kettle.

[0045] In a preferred embodiment, the recrystallization is carried out under the following conditions: using petroleum ether and / or C5 - C10 alkanes as solvents, at normal pressure and a temperature of -20 - 50 °C, to obtain a refined dioxirane product.

[0046] In the present invention, step (1) can be carried out in an epoxidation fixed-bed reactor, and step (2) can be carried out in a CHP decomposition reactor.

[0047] In the present invention, to epoxidize both double bonds of the diene, an excessive amount of CHP is used to participate in the epoxidation reaction. Therefore, a certain amount of CHP remains in the mixed material at the end of the reaction. To prevent the residual CHP from entering the separation unit, the present invention uses a CHP decomposition reactor to consume the residual CHP in the system.

[0048] The method of the present invention is a new and efficient process for preparing dioxirane with mild reaction process conditions, environmental friendliness, and good technical economy. It can be used in large-scale industrial production and has good technical application prospects.

[0049] The second object of the present invention is to provide a system for preparing dioxirane, which is used to carry out the method as described above, including:

[0050] Epoxidation reaction device: It is configured to receive diene and cumene hydroperoxide, and discharge a mixed stream containing cumene hydroperoxide, α,α-dimethylbenzyl alcohol, dioxirane, and cumene;

[0051] Decomposition reaction device: It is configured to receive the mixed stream containing cumene hydroperoxide, α,α-dimethylbenzyl alcohol, dioxirane, and cumene, and discharge a mixed stream containing methanol, acetophenone, α,α-dimethylbenzyl alcohol, dioxirane, and cumene;

[0052] Post-treatment device: It includes a first distillation column, a water washing kettle, a second distillation column, a third distillation column, and a crystallization kettle connected in series in sequence. The first distillation column receives the mixed stream containing methanol, acetophenone, α,α-dimethylbenzyl alcohol, and dioxirane, and the crystallization kettle discharges dioxirane.

[0053] In a preferred embodiment, the epoxidation reaction device uses an epoxidation fixed-bed reactor.

[0054] In a preferred embodiment, the decomposition reaction device uses a CHP decomposition reactor.

[0055] Compared with the prior art, the present invention has the following beneficial effects:

[0056] (1) The method of the present invention uses an excessive amount of cumene hydroperoxide to ensure the yield of the reaction product and avoid product loss.

[0057] (2) By adopting the series connection mode of an epoxidation reactor and a CHP decomposition reactor, the unreacted CHP is completely consumed and enters the separation unit.

[0058] (3) By decomposing CHP under high-temperature alkaline conditions, the products are methanol / acetophenone, avoiding the risk of ring-opening hydrolysis of dioxirane into by-products, which is beneficial to ensuring the yield of subsequent products. Brief Description of the Drawings

[0059] Figure 1 It is a process flow schematic diagram of a method for preparing dioxirane according to the present invention.

[0060] Figure 1 Marking Explanation:

[0061] 1: Epoxidation fixed-bed reactor;

[0062] 2: CHP decomposition reactor;

[0063] 3: Water washing kettle;

[0064] 4: Crystallization kettle;

[0065] C1: First distillation column;

[0066] C2: Second distillation column;

[0067] C3: Third distillation column;

[0068] A: Mixed stream containing cumene hydroperoxide, α,α-dimethylbenzyl alcohol, epoxidized compound dioxide, and cumene;

[0069] B: Mixed stream after decomposition reaction;

[0070] C: Stream after primary distillation;

[0071] D: Deionized water;

[0072] E: Stream after water washing;

[0073] F: Stream after secondary distillation;

[0074] 11: Methanol;

[0075] 12: Waste water;

[0076] 13: Cumene;

[0077] 14: Stream containing most of α,α-dimethylbenzyl alcohol and acetophenone;

[0078] 15: Crude epoxidized compound dioxide stream containing a small amount of α,α-dimethylbenzyl alcohol.

[0079] Figure 1In it, the epoxidation of diolefin and cumene hydroperoxide occurs in a fixed-bed reactor 1 to obtain a mixed stream A containing cumene hydroperoxide, α,α-dimethylbenzyl alcohol, epoxidized compound dioxide and cumene. The mixed stream A enters a CHP decomposition reactor 2. Cumene hydroperoxide decomposes under the action of a basic catalyst to generate methanol and acetophenone. The mixed stream B after the decomposition reaction enters a first distillation column C1. Methanol 11 flows out from the top of the column. The stream C after the first distillation flowing out from the bottom of the column enters a water washing kettle 3. The lower-layer wastewater 12 separated after washing with deionized water D is discharged from the system. The upper-layer stream E after water washing enters a second distillation column C2. Cumene 13 flows out from the top of the column. The stream F after the second distillation flowing out from the bottom of the column enters a third distillation column C3. The stream 14 containing most of α,α-dimethylbenzyl alcohol and acetophenone flows out from the top of the column. The crude epoxidized compound dioxide stream 15 containing a small amount of α,α-dimethylbenzyl alcohol flowing out from the bottom of the column enters a crystallization kettle 4. After recrystallization, a refined epoxidized compound dioxide product is obtained. Specific Embodiments

[0080] The present invention will be specifically described below in conjunction with specific embodiments. It is necessary to point out here that the following embodiments are only for further illustration of the present invention and cannot be construed as limiting the protection scope of the present invention. Some non-essential improvements and adjustments made by those skilled in the art according to the content of the present invention still fall within the protection scope of the present invention.

[0081] In addition, it should be noted that the various specific technical features described in the following specific embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the present invention will not separately describe various possible combination methods.

[0082] In addition, any combination can be made between various different embodiments of the present invention as long as it does not violate the idea of the present invention. The technical solutions formed thereby belong to a part of the original public content of this specification and also fall within the protection scope of the present invention.

[0083] In the following embodiments, unless otherwise specified, the experimental methods used are all conventional methods, and the materials, reagents, etc. used can be purchased from domestic chemical companies.

[0084] The reaction is carried out according to the following process in the embodiments:

[0085] The epoxidation reaction of diolefin and cumene hydroperoxide occurs in the fixed-bed reactor 1, and the resulting mixed stream A containing cumene hydroperoxide, α,α-dimethylbenzyl alcohol, epoxidized compound dioxide, and cumene enters the CHP decomposition reactor 2. Cumene hydroperoxide decomposes into methanol and acetophenone under the action of an alkaline catalyst. The resulting mixed stream B after the decomposition reaction enters the first distillation column C1. Methanol 11 flows out from the top of the column, and the stream C after the first distillation flowing out from the bottom of the column enters the water washing kettle 3. The lower-layer wastewater 12 separated after washing with deionized water D is discharged from the system, and the upper-layer stream E after water washing enters the second distillation column C2. Cumene 13 flows out from the top of the column, and the stream F after the second distillation flowing out from the bottom of the column enters the third distillation column C3. The stream 14 containing most of α,α-dimethylbenzyl alcohol and acetophenone flows out from the top of the column, and the crude epoxidized compound dioxide stream 15 containing a small amount of α,α-dimethylbenzyl alcohol flowing out from the bottom of the column enters the crystallization kettle 4. After recrystallization, the refined epoxidized compound dioxide product is obtained.

[0086]

Example 1

[0087] The epoxidation reaction of 50% CHP oxidation liquid and dicyclopentadiene (DCPD) is carried out in an epoxidation fixed-bed reactor equipped with titanium-loaded HMS mesoporous molecular sieve (Shanghai Research Institute of Petrochemical Technology, CHPO-2000 series Ti-HMS catalyst) to generate dicyclopentadiene dioxide (DCPDDO) and α,α-dimethylbenzyl alcohol (DMBA). Among them, CHP / DCPD = 3:1 (mole), WHSV(DCPD) = 1 h -1 , the reaction temperature is 90 °C, and the reaction pressure is 1.0 MPa. Using on-line chromatography for quantitative analysis, the contents of each component in the product are: cumene 40%, DMBA 27%, DCPDDO 20%, CHP 12%, DCPD and other undetermined components 1%. The conversion rate of DCPD is 99.5%, and the selectivity of DCPDDO is 99.9%.

[0088] The reaction material at the outlet of the above epoxidation fixed-bed reactor is introduced into the CHP decomposition reactor, the catalyst is porous calcium oxide, the reaction temperature is 110 °C, and the pressure is 1.0 MPa. After sufficient reaction, the remaining CHP decomposes into methanol and acetophenone. The conversion rate of CHP is 99.9%, and the selectivity of methanol and acetophenone is 99.5%. The contents of each component in the product are: cumene 40%, DMBA 27%, DCPDDO 20%, methanol 3%, acetophenone 9%, DCPD and other undetermined components 1%.

[0089] The materials at the outlet of the CHP decomposition reactor are subjected to operations such as distillation, water washing, and recrystallization:

[0090] (1) Introduce into the first distillation column C1, and separate the light component methanol generated by the reaction from the top of the column; the conditions of the first distillation column are: the top temperature is 60 °C, and the pressure is 0 MPa;

[0091] (2) The conditions for water washing are as follows: the ratio of deionized water to the material flow after the first rectification is 10:100.

[0092] (3) The conditions for the second rectification column C2 are as follows: the top temperature is 100 °C and the pressure is 0.04 MPa.

[0093] (4) The conditions for the third rectification column C3 are as follows: the top temperature is 100 °C and the pressure is 0.04 MPa.

[0094] (5) The crude dicyclopentadiene dioxide is subjected to recrystallization in a crystallization kettle using petroleum ether as a solvent under normal pressure and at 10 °C to obtain a refined DCPDDO product. After the recrystallization step, the total product yield is calculated to be 73%, the product content analyzed by GC is 99.2%, and the content of other unknown components is 0.8%.

[0095]

Example 2

[0096] 40% CHP oxidation liquid is subjected to an epoxidation reaction with 4-vinylcyclohexene in an epoxidation fixed-bed reactor equipped with titanium-loaded HMS mesoporous molecular sieve (Shanghai Research Institute of Petrochemical Technology, CHPO-2000 series Ti-HMS catalyst) to produce vinylcyclohexene dioxide and α,α-dimethylbenzyl alcohol (DMBA). Among them, CHP / 4-vinylcyclohexene = 2.5:1 (mole), WHSV(4-vinylcyclohexene) = 1 h -1 , the reaction temperature is 90 °C, and the reaction pressure is 1.0 MPa. Using on-line chromatography for quantitative analysis, the contents of each component in the product are as follows: cumene 57%, DMBA 20%, vinylcyclohexene dioxide 13%, CHP 9%, 4-vinylcyclohexene and other undetermined components 1%. The conversion rate of 4-vinylcyclohexene is 99.5%, and the selectivity of vinylcyclohexene dioxide is 99.6%.

[0097] The reaction material at the outlet of the above epoxidation fixed-bed reactor is fed into a CHP decomposition reactor with a macroporous strongly basic styrene-based anion exchange resin (Tianyuan Shanghai Resin Factory, D202 type anion exchange resin) as the catalyst, the reaction temperature is 100 °C, and the pressure is 1.0 MPa. After sufficient reaction, the remaining CHP is decomposed into methanol and acetophenone. The conversion rate of CHP is 99.9%, and the selectivity of methanol and acetophenone is 99.6%. The contents of each component in the product are as follows: the contents of each component in the product are: cumene 57%, DMBA 20%, vinylcyclohexene dioxide 13%, methanol 2%, acetophenone 7%, 4-vinylcyclohexene and other undetermined components 1%.

[0098] The material at the outlet of the CHP decomposition reactor is subjected to operations such as rectification, alkali washing, and recrystallization:

[0099] (1) Introduce the first distillation column C1, and separate the light component methanol generated by the reaction from the top of the column; the conditions of the first distillation column C1 are: the top temperature is 60 °C, the pressure is 0.07 MPa,

[0100] (2) The conditions for water washing are: the ratio of deionized water to the material flow after the first distillation is 10:100.

[0101] (3) The conditions of the second distillation column C2 are: the top temperature is 70 °C, the pressure is 0.03 MPa;

[0102] (4) The conditions of the third distillation column C3 are: the top temperature is 100 °C, the pressure is 0.03 MPa;

[0103] (5) Recrystallize the crude vinyl cyclohexene dioxide in a crystallization kettle, using petroleum ether as the solvent, under normal pressure and at 10 °C, to obtain the refined vinyl cyclohexene dioxide product. After the recrystallization step, calculate the total product yield to be 72%, the product content analyzed by GC is 99.0%, and other unknown components are 1.0%

[0104]

Comparative Example 1

[0105] Add acetic acid and 30 wt% H 2 O 2 to an enamel reaction kettle in a molar ratio of acetic acid to H 2 O 2 of 3:1. Then add 98% concentrated sulfuric acid to the above reaction kettle as a catalyst, and the addition amount of concentrated sulfuric acid is 0.5% of the total mass of acetic acid and H 2 O 2 . Stir and react at 40 - 45 °C for 2.5 h, stop stirring, and use the prepared peracetic acid as the oxidant for the epoxidation reaction.

[0106] Add DCPD to another enamel reaction kettle containing an appropriate amount of sodium acetate trihydrate, and stir and preheat the material in the reaction kettle to 40 °C. Slowly add the above-prepared peracetic acid solution to the DCPD mixture, where the molar ratio of DCPD to peracetic acid is 1:3, control the reaction temperature at 40 - 45 °C, the addition time of peracetic acid is about 5 h. After the addition of peracetic acid is completed, continue to stir and react for 2 h. When the mass fraction of peracetic acid in the kettle is lower than 5%, stop the reaction.

[0107] After the epoxidation mixture is subjected to operations such as vacuum distillation, neutralization, washing, and drying, the DCPDDO product is obtained. The melting point of the product is 184 °C, and the yield is 70%.

[0108]

Comparative Example 2

[0109] Take 100 mL of the oxidized organic reaction solution collected from the outlet of the epoxidation fixed-bed reactor in the first step of Example 1, add 50 mL of 10% aqueous ammonia solution, stir at 50 °C for 2 hours, then transfer it to a separatory funnel and let it stand. Collect the upper organic phase. The content of CHP is measured to be about 11%, which is basically equivalent to the content of the reaction solution at the reactor outlet.

[0110]

Comparative Example 3

[0111] Take 100 mL of the oxidized organic reaction solution collected from the outlet of the epoxidation fixed-bed reactor in the first step of Example 1, add 50 mL of 10% sulfuric acid solution, stir at 50 °C for 2 hours, then transfer it to a separatory funnel and let it stand. Collect the upper organic phase. The content of cumene is measured to be 48%, DMBA 33%, DCPDDO 1%, phenol 9%, acetone 5%, and DCPD and other undetermined components 4%. A large amount of DCPDDO is lost.

[0112] The method of the present invention avoids the use of peracetic acid, greatly improves the reaction safety, and also avoids the problem of corrosion of the reaction vessel.

Claims

1. A method for preparing epoxy dioxide, comprising contacting a mixture obtained by oxidation reaction of diene and cumene hydroperoxide with an alkaline catalyst to decompose cumene hydroperoxide to produce acetophenone and methanol, and then performing post-treatment to separate and obtain epoxy dioxide.

2. The method according to claim 1, characterized in that The following steps are involved: (1) in the presence of a catalyst, allowing a diene to undergo an oxidation reaction with cumene hydroperoxide to obtain a mixed stream comprising cumene hydroperoxide, α,α-dimethylbenzyl alcohol, a dioxide epoxy compound and cumene; (2) contacting the mixed stream with an alkaline catalyst to decompose cumene hydroperoxide to produce acetophenone and methanol; (3) post-treating the logistics obtained in step (2) to separate and obtain the epoxy dioxide compound.

3. The method according to claim 2, characterized in that In step (1): The diene is at least one of dicyclopentadiene, vinyl cyclohexene, dimethyl vinyl cyclohexene and dipentene; The catalyst is selected from at least one of titanium silicon molecular sieve, titanium silicon mixed oxide, and titanium-supported silicon dioxide; and / or, The molar ratio of cumene hydroperoxide to diene is (2-20):1, preferably (2-10):1; and / or, The conditions of the oxidation reaction are: temperature 0-200° C., pressure 0-20 MPa, preferably: temperature 50-150° C., pressure 0-10 MPa.

4. The method according to claim 2, characterized in that In step (2): The alkaline catalyst is a solid base catalyst, and the alkaline catalyst is preferably at least one selected from metal oxides, KF supported by porous compounds, metal oxyacid salts, and styrene-based anion exchange resins, and the metal oxide is more preferably at least one selected from CaO, MgO, SrO, and BaO; and / or, The conditions for the decomposition reaction are: temperature 0-300° C., pressure 0-5 MPa; preferably: 100-300° C., 0.5-3 MPa.

5. The method according to claim 2, characterized in that In step (3): The post-treatment includes primary distillation, water washing, secondary distillation, tertiary distillation and recrystallization in sequence.

6. The method according to claim 5, characterized in that: In the primary distillation, the temperature at the top of the distillation tower is 0 to 150°C, and the pressure is -0.01 to 11 MPa.

7. The method according to claim 5, characterized in that: In the water washing, the weight ratio of water to the logistics after the primary distillation is (0.001-15):

100.

8. The method according to claim 5, characterized in that: The temperature of the top of the distillation tower in the secondary distillation is 50-140°C and the pressure is -0.01-0.10 MPa; and / or the temperature of the top of the distillation tower in the tertiary distillation is 60-120°C and the pressure is -0.06-0.10 MPa.

9. The method according to claim 5, characterized in that: The solvent for recrystallization is petroleum ether and / or C5-C10 alkane, and / or, The recrystallization temperature is -20 to 50°C.

10. A system for preparing epoxy dioxide, for carrying out the method according to any one of claims 1 to 9, comprising: An oxidation reaction unit: the oxidation reaction unit is configured to receive dienes and cumene hydroperoxide and discharge a mixed stream containing cumene hydroperoxide, α,α-dimethylbenzyl alcohol, epoxide dioxide and cumene; A decomposition reaction device: the decomposition reaction device is configured to receive a mixed stream containing cumene hydroperoxide, α,α-dimethylbenzyl alcohol, epoxy dioxide and cumene, and discharge a mixed stream containing methanol, acetophenone, α,α-dimethylbenzyl alcohol, epoxy dioxide and cumene; The post-processing device comprises a first distillation tower, a water washing kettle, a second distillation tower, a third distillation tower and a crystallization kettle which are connected in series in sequence, wherein the first distillation tower receives a mixed flow containing methanol, acetophenone, α,α-dimethylbenzyl alcohol and epoxy dioxide, and the crystallization kettle discharges epoxy dioxide.

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