Method for preparing dicyclopentadiene monoepoxide

Abstract

The invention provides a method for preparing dicyclopentadiene monoepoxide, which comprises the following steps of: by taking dicyclopentadiene as a reaction raw material, tert-butyl hydroperoxide, tert-amyl hydroperoxide or cumyl hydroperoxide as an oxidizing agent and a titanium silicalite molecular sieve as a catalyst, reacting in an inert solvent at the temperature of 60-80 DEG C for 2-4 hours, thereby obtaining the dicyclopentadiene monoepoxide. According to the method, dicyclopentadiene, an oxidizing agent and a titanium silicalite molecular sieve catalyst are in full contact to generate a catalytic oxidation reaction, a mixed solution containing dicyclopentadiene monoepoxide is generated, the DCPD monoepoxide is prepared through separation and purification, the molar ratio of DCPD to CHP is (1-4): 1, and the reaction temperature is 60-120 DEG C. And the reaction product is subjected to rectification separation, such that the DCPD monoepoxide with a mass fraction of 87.6-92.0% is obtained.

Description

Technical Field

[0001] The present invention belongs to the technical field of catalytic oxidation synthesis of organic epoxy compounds and catalytic oxidation of olefins, and specifically relates to a method for preparing and separating dicyclopentadiene monoepoxide by using dicyclopentadiene as a raw material and titanium silicon molecular sieve as a catalyst. Background Art

[0002] Dicyclopentadiene (DCPD), scientific name is tricyclo[5.2.1.0 2,6 ]Decadiene-3,8, has two double bonds in its molecule. When dicyclopentadiene DCPD is in excess, it undergoes epoxidation reaction with organic peroxides to form two monoepoxides, generally called dicyclopentadiene monoepoxide. Each molecule of this compound contains one epoxy bond and one olefin bond, and has a bifunctional structure. It has good application prospects in the fields of medicine, pesticides and other fine chemicals, epoxy resin composite materials, etc. DCPD reacts with organic peroxides to form DCPD monoepoxide, see reaction formula (1):

[0003]

[0004] DCPD monoepoxide (1), (3), scientific name: 9-oxatetracyclo[5.3.1.0 2,6 .0 8,10 ]Undec-3-ene

[0005] DCPD monoepoxide (2), (4), scientific name: 4-oxatetracyclo[6.2.1.0 2,7 .0 3,5 ]Undec-9-ene

[0006] Existing literature (Huang Zhitong, Han Xiaozu. Four (3,4), (8,9)-bisepoxy-tris[5.2.1.0 2,6 [Synthesis and Configuration of Decane] Acta Chimica Sinica, 1979, 37(1): 23-28) discloses a method for synthesizing DCPD monoepoxide: 77 g of exo-DCPD (0.58 mol) was reacted with 66.8 g (0.29 mol) of 33.6% peracetic acid to produce 28.9 g of DCPD monooxide (1) and (2) with a yield of 67%. According to the method of Pirsch (see reference: J. Pirsch, Monatsh. Chem. 85, 154, 1954), 95.3 g of endo-DCPD was reacted with an equimolar mass fraction of 33.6% peracetic acid to produce 53 g of a mixture of DCPD monoepoxides (3) and (4) with a yield of 50%.

[0007] Since peracetic acid contains 47% acetic acid, 21% water, and 5% sulfuric acid, under the catalysis of sulfuric acid, the olefin bonds in DCPD and the epoxy bonds in DCPD monoepoxides (1), (2) or (3), (4) will react with acetic acid and water to form a variety of by-products, which greatly increases the difficulty of separating and purifying the reaction products. Obviously, the existing peracetic acid method for preparing DCPD monoepoxide has poor process safety. The presence of sulfuric acid and acetic acid in the reaction products makes side reactions prone to occur, equipment corrosion is serious, and a large amount of process wastewater is produced. Peracetic acid is a strong oxidant and is extremely unstable. It will explode at -20°C. It is explosive when the concentration is greater than 45%. It will explode when exposed to high heat, reducing agents, or the presence of metal ions. Peracetic acid is included in the "List of Dangerous Chemicals that Can Be Easily Exploded (2022 Edition)".

[0008] Because the DCPD molecule has two double bonds, adding an organic peroxide will produce both dicyclopentadiene monoepoxide and dicyclopentadiene diepoxide. To control the conversion of DCPD to the monoepoxide, an excess of DCPD must be added. However, this excess DCPD poses numerous challenges to product separation and purification, and also negatively impacts catalyst activity. Summary of the Invention

[0009] An object of the present invention is to provide a method for preparing dicyclopentadiene monoepoxide.

[0010] Another object of the present invention is to provide a method for separating dicyclopentadiene monoepoxide.

[0011] In one aspect, the present invention provides a method for preparing dicyclopentadiene monoepoxide, comprising: using dicyclopentadiene (DCPD) as a raw material, an organic peroxide as an oxidant, and a titanium silicalite as a catalyst; in an inert solvent, the DCPD, the oxidant, and the titanium silicalite catalyst are fully contacted to undergo a catalytic oxidation reaction to generate a mixture containing the DCPD monoepoxide; and separating and purifying the mixture to obtain the DCPD monoepoxide.

[0012] The titanium silicate molecular sieve catalyst is a modified Ti-HMS molecular sieve catalyst with mesoporous characteristics, and its components include: TiO2 mass fraction of 0.10% to 6.42%, nano-carbon fiber mass fraction of 44.68% to 64.11%, SiO2 mass fraction of 28.17% to 45.80%, magnesium oxide mass fraction of 0.01% to 1.98%, and silane mass fraction of 0.44% to 6.93%;

[0013] The catalytic oxidation reaction temperature is 60-120° C., the molar ratio of DCPD to the oxidant is 1-4:1, preferably 3-4:1, and the DCPD monoepoxide has the structure of formula (1), (2), (3) or (4):

[0014]

[0015] Furthermore, the organic peroxide oxidant is tert-butyl hydroperoxide, tert-amyl hydroperoxide or cumene hydroperoxide (CHP).

[0016] Furthermore, the inert solvent used in the epoxy reaction system is an organic hydrocarbon compound such as benzene, toluene, cumene, cyclohexane, heptane, octane, decanane, etc., and cumene is preferably used as the solvent.

[0017] Furthermore, the reaction raw material DCPD can be an endo structure or an exo structure, or a mixture of endo and exo structures. Usually, DCPD with an endo structure DCPD mass fraction of 98% and an exo structure DCPD mass percentage of less than 1% is selected.

[0018] On the other hand, the present invention provides a method for separating dicyclopentadiene monoepoxide, comprising: conveying a mixed liquid to a distillation tower for vacuum distillation separation; the mixture comprises DCPD, DCPD monoepoxide, DCPD diepoxide, an inert solvent and α,α-dimethylbenzyl alcohol.

[0019] The advantages of the present invention are that the HMS titanium silicon molecular sieve with mesoporous characteristics is used as a catalyst to synthesize the DCPD monoepoxide process, the reaction process is highly safe, there are few by-products, separation is simple, the wastewater discharge is small, and industrialization is easy to achieve. Specific embodiments

[0020] The following examples further illustrate the present invention, but the present invention is not limited to the examples. Some definitions in the present invention:

[0021] DCPD conversion rate = (moles of DCPD monoepoxide in the epoxidation reaction product + moles of DCPD diepoxide in the epoxidation reaction product) / total moles of DCPD fed into the epoxidation reactor * 100%;

[0022] DCPD monoepoxide selectivity = moles of DCPD monoepoxide in the epoxidation reaction product / (moles of DCPD monoepoxide in the epoxidation reaction product + moles of DCPD diepoxide in the epoxidation reaction product)*100%;

[0023] DCPD distillation yield = moles of DCPD collected per hour from the distillation tower / moles of DCPD input into the distillation tower per hour * 100%;

[0024] Cumene distillation yield = number of moles of cumene collected per hour from the distillation tower / number of moles of cumene in the material input to the distillation tower per hour * 100%;

[0025] α,α-dimethylbenzyl alcohol distillation yield = number of moles of α,α-dimethylbenzyl alcohol collected per hour from the distillation tower / number of moles of α,α-dimethylbenzyl alcohol in the distillation tower input per hour * 100%;

[0026] DCPD monoepoxide distillation yield = moles of DCPD monoepoxide collected in the distillation tower kettle per hour / moles of DCPD monoepoxide in the distillation tower material input per hour * 100%;

[0027] The process yield of DCPD monoepoxide = the number of moles of DCPD monoepoxide generated in each batch of epoxidation reaction / (the number of moles of DCPD fed into the reactor in this batch - the number of moles of DCPD recovered by distillation separation in this batch) * 100%.

[0028] According to the method provided by this invention, titanium-containing hexagonal mesoporous silica, denoted as Ti / HMS, is used to synthesize DCPD monoepoxide. The main preparation steps are as follows: (1) Preparation of hexagonal mesoporous silica powder: Dissolve an appropriate amount of long-chain fatty amine in an ethanol-water solution and stir to obtain solution A. Dissolve an appropriate amount of tetraethyl orthosilicate in ethanol to obtain solution B. Quickly add solution B to solution A, stir vigorously, and allow to age at room temperature to obtain a precipitate. This precipitate is then filtered, washed, dried, and calcined at high temperature to obtain pure silicon HMS powder. (2) Carrier Formation: Add the HMS powder and additives in a kneader according to a specific ratio, stir thoroughly to mix, then add a binder, knead, extrude, extrude, dry, and calcinate to obtain a shaped HMS carrier. (3) Chemical Vapor Deposition of Titanium: Place the shaped HMS carrier in a quartz tubular reactor, heat under inert gas, and introduce TiCl4 vapor. After a period of reaction, purge with inert gas to obtain a Ti / HMS sample. (4) The Ti / HMS sample prepared above is placed in a quartz tube reactor, and a silanization reagent is introduced by an inert gas. The reaction is carried out for a certain time under dry conditions, and the excess unreacted silanization reagent is removed. The sample is then cooled to room temperature in an inert gas environment.

[0029] According to the method provided by the present invention, titanium-containing hexagonal mesoporous silica Ti / HMS for synthesizing DCPD monoepoxide has a strong absorption peak at a wavelength of 220 nm in the UV-vis spectrum of the Ti / HMS sample before silylation treatment. After alkylation treatment, the UV-vis spectrum of the Ti / HMS sample has a strong absorption peak at a wavelength of 215 nm, and a BET surface area of ​​550.5 m 2 / g, average pore diameter 2.7nm, pore volume 0.65cm 3 / g.

[0030] According to the method provided by the present invention, titanium-containing hexagonal mesoporous silica Ti / HMS for synthesizing DCPD monoepoxide, the preparation method thereof includes but is not limited to the methods disclosed in the following documents: (I) Jin Guojie, Gao Huanxin, Yang Hongyun, et al. Characterization of post-synthesized Ti / HMS catalyst and its catalytic epoxidation performance for propylene [J]. Molecular Catalysis, 2010, 24(1): 6-11. (II) Wang Chao, Jin Guojie, Gao Huanxin, et al. Hydrophobically modified Ti / HMS catalyst for propylene epoxidation process. [C] 2015 Proceedings of the Annual Conference of the Chemical Industry Society of China. Engineering Technology I, 2015: 1-7.

[0031] According to the method provided by the present invention, a Ti / HMS catalyst having mesoporous characteristics is prepared for use in preparing DCPD monoepoxide, and its preparation method includes but is not limited to the methods disclosed in the following Chinese patents: CN102874835B, CN112723377B, CN104437636B, CN104437450B, CN104437618B, CN104437635B, CN113083358A, CN113083359A, and CN113083360A.

[0032] According to the method provided by the present invention, the reactor can be a suspended bed reactor or a solid bed reactor.

[0033] According to the method provided by the present invention, the amount of catalyst used is 0.8% to 12.5% ​​(the percentage of the mass of the catalyst to the total mass of the liquid material fed into the reactor).

[0034] According to the method provided by the present invention, pressure has no significant effect on the reaction, and the reaction can be carried out at normal pressure or under pressure. The reaction pressure is preferably 0.1 to 1.7 MPa.

[0035] According to the method provided by the present invention, the epoxidation reaction temperature is 60 to 120° C., and the reaction materials are preferably fully contacted with the catalyst for 1 to 3 hours.

[0036] According to the method provided by this Fang Ming, the oxidants cumene hydroperoxide, tert-butyl hydroperoxide or tert-amyl hydroperoxide are not included in the "List of Dangerous Chemicals that are Easily Explosive and Preservative (2022 Edition)".

[0037] The preparation method of dicyclopentadiene monoepoxide adopts titanium silicon molecular sieve to catalyze the epoxidation reaction in an inert solvent, is non-corrosive, uses cumene hydroperoxide, tert-butyl hydroperoxide or tert-amyl hydroperoxide as the oxidant, is highly safe, does not require water washing, has a wide reaction temperature operating range, can be subjected to a fixed-bed continuous reaction, and is easy to realize large-scale industrial production.

[0038] According to the method provided by the present invention, after the epoxidation reaction products of DCPD and isopropylbenzene hydroperoxide, tert-butyl peroxide, and tert-amyl peroxide leave the reactor, they are transported to a distillation tower for vacuum distillation separation. The separated inert solvent and DCPD are reused in the DCPD monoepoxidation reaction, and α,α-dimethylbenzyl alcohol, tert-butyl alcohol, and tert-amyl alcohol can be used as by-products.

[0039] In the embodiment, the reaction product used for distillation has the following mass percentage composition: DCPD 1.6% to 21.4%, DCPD monoepoxide 5.1% to 7.7%, DCPD diepoxide 0.6% to 2.5%, inert solvent 59.9% to 80.4%, α,α-dimethylbenzyl alcohol 8.7% to 11.1%, and cumene hydroperoxide <0.2%.

[0040] A two-tower series distillation separation process is employed. The reaction material (the mixed liquid after the epoxidation reaction of DCPD and cumene hydroperoxide) is used as the distillation raw material) is transported to a first distillation tower, where a mixture of DCPD and an inert solvent is collected at the top of the tower. The bottom of the tower is then transported to a second distillation tower; α,α-dimethylbenzyl alcohol is collected at the top of the second distillation tower, while a mixture of DCPD monoepoxide and DCPD diepoxide is collected at the bottom of the tower. The first distillation tower has 6 to 20 stages, a reflux ratio of 1 to 4, a top temperature of 66.4 to 98.3°C, a top pressure of 5 to 18 kPa, and a bottom temperature of 117.7 to 151.6°C. The second distillation tower has 15 to 30 stages, a reflux ratio of 4 to 8, a top temperature of 112.9 to 130.1°C, a top pressure of 5 to 10 kPa, and a bottom temperature of 126.4 to 145.9°C.

[0041] A single-tower distillation separation process was employed. The reaction materials (the mixed liquid after the epoxidation reaction of DCPD and cumene hydroperoxide was used as the distillation raw material) were transported to a distillation tower, where the solvent and DCPD were collected at the top of the tower, and the DCPD monoepoxide was collected in the bottom of the tower. The distillation tower had 6 to 20 stages, a reflux ratio of 1 to 4, a top temperature of 65.5 to 84.9°C, a top pressure of 5 to 15 kPa, and a bottom temperature of 127.0 to 157.4°C.

[0042] The mass percentage composition of the reaction materials of the present invention is determined by gas chromatography analysis. The mass percentage of DCPD monoepoxide in the reaction product is the sum of the mass percentages of the four structures of DCPD monoepoxide in the above reaction formula (1).

[0043] The titanium silicate molecular sieve catalyst used in the following examples is a modified Ti-HMS molecular sieve catalyst with mesoporous characteristics, whose components include: TiO2 mass fraction of 0.10% to 6.42%, nano-carbon fiber mass fraction of 44.68% to 64.11%, SiO2 mass fraction of 28.17% to 45.80%, magnesium oxide mass fraction of 0.01% to 1.98%, and silane mass fraction of 0.44% to 6.93%.

[0044] Example 1

[0045] In a 150-ml stainless steel reactor equipped with magnetic stirring, 6.4 g of DCPD (98% purity), 9.1 g of cumene hydroperoxide (82% purity), 43.5 g of benzene solvent (99% purity), and 0.7 g of HMS titanium silicalite were added. The catalyst composition was: 62.90% by mass of carbon nanofibers, 2.57% by mass of TiO2, 31.32% by mass of SiO2, 0.83% by mass of MgO, and 2.38% by mass of silane groups. The molar ratio of DCPD to cumene hydroperoxide added to the reactor was 1:1, and the catalyst dosage was 1.2% (based on the mass ratio of catalyst to the total mass of liquid materials added to the reactor). The reactor was purged with nitrogen, and the reactor outlet valve was closed. Magnetic stirring was activated, and oil bath heating was used. The reaction temperature was controlled at 90°C. The reaction pressure was maintained at 1.0 MPa by adjusting the valve on the air inlet line connected to the nitrogen line. After 2 hours of reaction, the mixture was cooled to room temperature, sampled, and the product composition was analyzed by gas chromatography. The reaction product contained a DCPD mass fraction of 1.6%, a DCPD monoepoxide mass fraction of 5.1%, and a dicyclopentadiene diepoxide mass fraction of 2.5%. The DCPD conversion was 80.5%, and the selectivity for DCPD monoepoxide was 69.7%.

[0046] Example 2

[0047] In a 150-ml stainless steel reactor equipped with magnetic stirring, 12.9 grams of DCPD (98% purity), 9.1 grams of cumene hydroperoxide (82% purity), 43.5 grams of toluene (99% purity), and 0.7 grams of HMS-structured titanium silicalite were added. The catalyst composition was: 64.11% by mass of carbon nanofibers, 3.63% by mass of TiO₂, 28.17% by mass of SiO₂, 0.01% by mass of MgO, and 4.08% by mass of silane groups. The molar ratio of DCPD to cumene hydroperoxide added to the reactor was 2:1, and the catalyst dosage was 1.1% (based on the mass ratio of catalyst to the total mass of liquid materials added to the reactor). The reactor was purged with nitrogen, and the reactor outlet valve was closed. Magnetic stirring was activated, and oil bath heating was used. The reaction temperature was controlled at 90°C. The reaction pressure was maintained at 1.0 MPa by adjusting the valve on the air inlet line connected to the nitrogen line. After 1.5 hours of reaction, the mixture was cooled to room temperature, sampled, and the product composition was analyzed by gas chromatography. The reaction product had a DCPD mass fraction of 9.2%, a DCPD monoepoxide mass fraction of 7.6%, and a dicyclopentadiene diepoxide mass fraction of 1.1%. The DCPD conversion was 45.6%, and the selectivity for DCPD monoepoxide was 88.1%.

[0048] Example 3

[0049] In a 150-ml stainless steel reactor equipped with magnetic stirring, 19.2 g of DCPD (98% purity), 9.1 g of cumene hydroperoxide (82% purity), 43.5 g of cumene (99% purity), and 0.7 g of HMS titanium silicalite were added. The catalyst composition was: 56.16% by mass of carbon nanofibers, 4.81% by mass of TiO₂, 33.13% by mass of SiO₂, 0.41% by mass of MgO, and 5.49% by mass of silane groups. The molar ratio of DCPD to cumene hydroperoxide added to the reactor was 3:1, and the catalyst dosage was 1.0% (based on the mass ratio of catalyst to the total mass of liquid materials added to the reactor). The reactor was purged with nitrogen, and the reactor outlet valve was closed. Magnetic stirring was activated, and oil bath heating was used. The reaction temperature was controlled at 90°C. The reaction pressure was maintained at 1.0 MPa by adjusting the valve on the air inlet line connected to the nitrogen line. After 1.5 hours of reaction, the mixture was cooled to room temperature, sampled, and the product composition was analyzed by gas chromatography. The reaction product had a DCPD mass fraction of 16.7%, a DCPD monoepoxide mass fraction of 7.1%, and a dicyclopentadiene diepoxide mass fraction of 0.6%. The DCPD conversion was 28.7%, and the selectivity for DCPD monoepoxide was 93.1%.

[0050] Example 4

[0051] In a 150-ml stainless steel reactor equipped with magnetic stirring, 25.4 g of DCPD (98% purity), 9.1 g of cumene hydroperoxide (82% purity), 43.5 g of cyclohexane (99% purity), and 0.7 g of HMS-structured titanium silicalite were added. The catalyst composition was: 53.20% by mass of carbon nanofibers, 6.12% by mass of TiO₂, 38.87% by mass of SiO₂, 0.47% by mass of MgO, and 1.34% by mass of silane groups. The molar ratio of DCPD to cumene hydroperoxide added to the reactor was 4:1, and the catalyst dosage was 0.9% (based on the mass ratio of catalyst to the total mass of liquid materials in the reactor). The reactor was purged with nitrogen, and the reactor outlet valve was closed. Magnetic stirring was activated, and oil bath heating was used. The reaction temperature was controlled at 90°C. The reaction pressure was maintained at 1.0 MPa by adjusting the valve on the air inlet line connected to the nitrogen line. After 1.5 hours of reaction, the mixture was cooled to room temperature, sampled, and the product composition was analyzed by gas chromatography. The reaction product had a DCPD mass fraction of 21.4%, a DCPD monoepoxide mass fraction of 7.7%, and a dicyclopentadiene diepoxide mass fraction of 0.6%. The DCPD conversion was 25.5%, and the selectivity for DCPD monoepoxide was 93.5%.

[0052] Example 5

[0053] In a 150-ml stainless steel reactor equipped with magnetic stirring, 19.2 g of DCPD (98% purity), 9.1 g of cumene hydroperoxide (82% purity), 43.5 g of octane (99% purity), and 9 g of HMS titanium silicalite were added. The catalyst composition was: 45.84% by mass of carbon nanofibers, 0.10% by mass of TiO2, 45.80% by mass of SiO2, 1.98% by mass of MgO, and 6.28% by mass of silane groups. The molar ratio of DCPD to cumene hydroperoxide added to the reactor was 3:1, and the catalyst dosage was 12.5% ​​(based on the mass ratio of catalyst to the total mass of liquid materials added to the reactor). The reactor was purged with nitrogen, and the reactor outlet valve was closed. Magnetic stirring was activated, and oil bath heating was used. The reaction temperature was controlled at 120°C. The reaction pressure was maintained at 1.7 MPa by adjusting the valve on the air inlet line connected to the nitrogen line. After one hour of reaction, the mixture was cooled to room temperature, sampled, and the product composition was analyzed by gas chromatography. The reaction product contained a DCPD mass fraction of 17.8%, a DCPD monoepoxide mass fraction of 8.2%, and a dicyclopentadiene diepoxide mass fraction of 0.7%. The DCPD conversion was 30.7%, and the selectivity for DCPD monoepoxide was 92.4%.

[0054] Example 6

[0055] In a 150 ml stainless steel reactor equipped with magnetic stirring, 19.2 g of DCPD (98% purity), 9.1 g of cumene hydroperoxide (82% purity), 21.4 g of heptane (99% purity), and 0.4 g of HMS titanium silicalite were added. The catalyst composition was: 58.56% by mass of carbon nanofibers, 6.42% by mass of TiO2, 33.94% by mass of SiO2, 0.64% by mass of MgO, and 0.44% by mass of silane groups. The molar ratio of DCPD to cumene hydroperoxide in the reactor was 3:1, and the catalyst dosage was 0.8% (based on the mass of catalyst to the total mass of liquid materials in the reactor). The reactor outlet valve was open to the atmosphere. Magnetic stirring was activated, and heating was performed in an oil bath at a temperature of 60°C. After a 3-hour reaction, the reaction mixture was cooled to room temperature, sampled, and the product composition analyzed by gas chromatography. In the reaction product, the mass fraction of DCPD was 24.4%, the mass fraction of DCPD monoepoxide was 11.5%, the mass fraction of dicyclopentadiene diepoxide was 1.0%, the DCPD conversion rate was 31.3%, and the selectivity for generating DCPD monoepoxide was 92.8%.

[0056] Example 7

[0057] In a 150-ml stainless steel reactor equipped with magnetic stirring, 6.4 grams of DCPD (98% purity), 5.0 grams of tert-amyl hydroperoxide (99% purity), 43.5 grams of decanane solvent (99% purity), and 0.7 grams of HMS titanium silicalite were added. The catalyst composition was: 48.95% by mass of carbon nanofibers, 5.32% by mass of TiO2, 38.65% by mass of SiO2, 0.67% by mass of MgO, and 6.41% by mass of silane groups. The molar ratio of DCPD to tert-amyl hydroperoxide added to the reactor was 1:1, and the catalyst dosage was 1.3% (based on the ratio of the mass of catalyst to the total mass of the liquid materials added to the reactor). The reactor was purged with nitrogen, and the reactor outlet valve was closed. Magnetic stirring was activated, and the reaction temperature was controlled at 90°C with oil bath heating. The reaction pressure was maintained at 1.0 MPa by adjusting the valve on the air inlet line connected to the nitrogen line. After 2 hours of reaction, the mixture was cooled to room temperature, sampled, and the product composition was analyzed by gas chromatography. The reaction product contained a DCPD mass fraction of 1.4%, a DCPD monoepoxide mass fraction of 5.4%, and a dicyclopentadiene diepoxide mass fraction of 2.2%. The DCPD conversion was 82.5%, and the selectivity for DCPD monoepoxide was 73.1%.

[0058] Example 8

[0059] In a 150 ml stainless steel reactor equipped with magnetic stirring, 19.2 g of DCPD (98% purity), 4.3 g of tert-butyl hydroperoxide (99% purity), 21.4 g of cumene (99% purity), and 1.0 g of HMS titanium silicalite were added. The catalyst composition was: 44.68% by mass of carbon nanofibers, 5.65% by mass of TiO2, 41.81% by mass of SiO2, 0.93% by mass of MgO, and 6.93% by mass of silane groups. The molar ratio of DCPD to tert-butyl hydroperoxide added to the reactor was 3:1, and the catalyst dosage was 2.2% (based on the mass of catalyst to the total mass of liquid materials added to the reactor). The reactor outlet valve was open to the atmosphere. Magnetic stirring was activated, and heating was performed in an oil bath at a temperature of 60°C. After a 3-hour reaction, the mixture was cooled to room temperature, sampled, and the product composition analyzed by gas chromatography. In the reaction product, the mass fraction of DCPD was 24.0%, the mass fraction of DCPD monoepoxide was 11.0%, the mass fraction of dicyclopentadiene diepoxide was 1.5%, the DCPD conversion rate was 31.5%, and the selectivity for generating DCPD monoepoxide was 89.0%.

[0060] Examples 9 to 14

[0061] The distillation separation process employed a two-tower series continuous distillation process. The first distillation tower had a feed rate of 50 g / h. The first distillation tower was 2000 mm tall, had an inner diameter of 35 mm, and a bottom volume of 10 L. The second distillation tower was 2000 mm tall, had an inner diameter of 35 mm, and a bottom volume of 5 L. Both towers were packed with stainless steel θ-ring packing (φ3 mm x 3 mm). The number of stages was adjusted by adjusting the packing height. Metering pumps were used for feed and bottom discharge of the first and second distillation towers. The overhead fraction was collected and discharged from the condenser pan into a storage tank using the liquid level difference. The overhead reflux condenser used -5°C low-temperature water for condensation and cooling, while the bottom material was evaporated using electrical heating. A reflux ratio controller controlled the overhead reflux rate. Two rotary vane vacuum pumps evacuated the two distillation towers to ensure that the distillation system pressure met the experimental requirements. The number of stages was calibrated before distillation.

[0062] The reaction product prepared in Example 3 was used as the raw material for the distillation experiment, and its mass percentage composition was: cumene 66.4%, DCPD 16.7%, α,α-dimethylbenzyl alcohol 9.2%, cumene hydroperoxide ∠0.1%, DCPD monoepoxide 7.1%, and DCPD diepoxide 0.6%.

[0063] Experimental steps: (i) Add 5L of distillation raw materials to the first distillation tower kettle, turn on the vacuum oil pump, set the system pressure according to the process requirements, keep the system pressure stable, turn on the electric heating device of the first distillation tower kettle, turn on the condensing water, adjust the kettle material temperature, and when there is distillate at the top of the first distillation tower, reflux for 3 hours. (ii) Turn on the sampling pump to deliver materials to the first distillation tower, adjust the reflux ratio, tower top pressure, tower top temperature, and tower kettle temperature according to the process setting requirements (as shown in Table 1). After the composition of the tower top and tower kettle materials is stable, turn on the discharge pump of the first distillation tower kettle to deliver materials to the second distillation tower, and collect DCPD and inert solvent at the top of the tower. (III) 2 to 3 L of material was collected from the bottom of the second distillation tower, the electric heating device of the bottom of the second distillation tower was turned on, the vacuum pump of the second distillation tower was turned on, and the pressure at the top of the second distillation tower and the temperature of the bottom material were adjusted. When there was a fraction at the top of the second distillation tower, after full reflux for 1 hour, the reflux ratio, bottom temperature, top pressure and top temperature of the second distillation tower were adjusted according to the process requirements (as shown in Table 2). After the operation of the second distillation tower was stable, the discharge pump of the bottom of the second distillation tower was turned on to transport the DCPD monooxide and a small amount of DCPD dioxide in the bottom material to a designated container, and a, a-dimethylbenzyl alcohol was collected from the top of the tower.

[0064] Experimental results: After the double-tower series distillation system was operated continuously and stably, the distillation separation effect was investigated. The experimental results are shown in Tables 1 and 2.

[0065] Table 1 Operating conditions of the first distillation tower for distillation separation of DCPD monoepoxide

[0066]

[0067] Table 2 Operating conditions of the second distillation column for distillation separation of DCPD monoepoxide

[0068]

[0069] As can be seen from Tables 1 and 2, through distillation separation, the DCPD distillation yield at the top of the first distillation tower is 97.1% to 99.5%, and the isopropyl benzene distillation yield is 99.7% to 100%, which can be recycled as reaction materials; α,α-dimethylbenzyl alcohol is collected at the top of the second distillation tower with a distillation yield greater than 96.5%, and the DCPD monoepoxide distillation yield in the bottom of the tower is greater than 99%, the mass percentage of DCPD monoepoxide is 87.6% to 92.0%, and the mass percentage of DCPD diepoxide is 8.0% to 12.4% (not listed in Table 2).

[0070] Examples 15 to 22

[0071] The distillation separation process employed a single-tower distillation process with a feed rate of 50 g / h. The distillation tower was 2000 mm tall, with an inner diameter of 35 mm and a bottom volume of 10 L. The packing consisted of stainless steel θ-ring packing measuring 3 mm x 3 mm in diameter. The number of stages was controlled by adjusting the packing height. Metering pumps were used for feed and bottom discharge. The overhead fraction was extracted and discharged from the condenser pan into a storage tank, utilizing the liquid level differential. The overhead reflux condenser used -5°C low-temperature water for condensation and cooling, while the bottom material was evaporated using electrical heating. A reflux ratio controller controlled the overhead reflux rate, and a rotary vane vacuum pump evacuated the distillation tower to maintain the distillation system pressure to meet experimental requirements. The number of stages was calibrated prior to distillation.

[0072] The reaction product prepared in Example 3 was used as the raw material for the distillation experiment, and its mass percentage composition was: cumene 66.4%, DCPD 16.7%, α,α-dimethylbenzyl alcohol 9.2%, cumene hydroperoxide ∠0.1%, DCPD monoepoxide 7.1%, and DCPD diepoxide 0.6%.

[0073] Experimental steps: (i) Add 5L of distillation raw materials to the distillation tower kettle, turn on the vacuum oil pump, set the system pressure according to the process requirements, keep the system pressure stable, turn on the distillation tower kettle electric heating device, turn on the condensing water, adjust the kettle material temperature, and when there is distillate at the top of the distillation tower, reflux for 3 hours. (ii) Turn on the sampling pump to transport materials to the distillation tower, adjust the reflux ratio according to the process setting requirements, when the system pressure, tower top temperature, tower bottom temperature, and distillate composition are stable, and the tower bottom material composition meets the process requirements, turn on the distillation tower bottom discharge pump to transport DCPD monoepoxide compound to the tower bottom material storage tank. The effect of distillation separation of DCPD monoepoxide compounds under different process conditions was investigated. The experimental process conditions, tower top fraction composition, distillation yield, tower bottom material composition and distillation yield are shown in Tables 3, 4, and 5, respectively.

[0074] Table 3 Distillation separation of DCPD monoepoxide operating conditions

[0075]

[0076] Table 4 Mass percentage composition and distillation yield of the overhead fraction of DCPD monoepoxide separation

[0077]

[0078] Table 5 Distillation separation of DCPD monoepoxide bottom material mass percentage composition and distillation yield

[0079]

[0080] As shown in Tables 3, 4, and 5, the distillation yield of DCPD and cumene is greater than 99% through distillation separation, and the recovered DCPD and cumene can be recycled as reaction materials. The number of distillation plates is ≥10, and the distillation yield of α,α-dimethylbenzyl alcohol is 92.2% to 99.3%. The number of distillation plates is 20, the mass fraction of DCPD monoepoxide is greater than 90%, and the distillation yield is greater than 98%.

[0081] The process of the present invention is used to synthesize DCPD monoepoxide. Excess DCPD fed into the reactor is recovered by distillation, and the distillation yield can be greater than 99%. Therefore, according to the method provided by the present invention, in the epoxidation reaction stage, the molar ratio of DCPD to CHP fed into the reactor is controlled at 3 to 4:1. After reaction and distillation separation, the process yield of DCPD monoepoxide can be greater than 90%.

Claims

1. A method for preparing dicyclopentadiene monoepoxide, comprising: Using dicyclopentadiene as a raw material, an organic peroxide as an oxidant, and a titanium silicon molecular sieve as a catalyst, in an inert solvent, dicyclopentadiene, the oxidant and the titanium silicon molecular sieve catalyst are fully contacted to undergo a catalytic oxidation reaction to generate a mixed liquid containing dicyclopentadiene monoepoxide, and the DCPD monoepoxide is obtained by separation and purification; The titanium silicon molecular sieve catalyst is a modified Ti-HMS molecular sieve catalyst with mesoporous characteristics, and its components include: TiO2 mass fraction of 0.10% to 6.42%, nano carbon fiber mass fraction of 44.68% to 64.11%, SiO2 mass fraction of 28.17% to 45.80%, magnesium oxide mass fraction of 0.01% to 1.98%, silane mass fraction of 0.44% to 6.93%; The catalytic oxidation reaction temperature is 60-120° C., the molar ratio of dicyclopentadiene to oxidant is 1-4:1, and the dicyclopentadiene monoepoxide has a structure of formula (1), (2), (3) or (4):

2. The method according to claim 1, characterized in that The organic peroxide oxidant is tert-butyl hydroperoxide, tert-amyl hydroperoxide or cumene hydroperoxide.

3. The method according to claim 1, characterized in that The molar ratio of dicyclopentadiene to the oxidant is 3 to 4:

1.

4. The method according to claim 1, characterized in that: The amount of the catalyst used is 0.8% to 12.5% ​​of the total mass of the dicyclopentadiene, the oxidant and the inert solvent.

5. The method according to claim 1, characterized in that The inert solvent is an organic hydrocarbon compound such as benzene, toluene, cumene, cyclohexane, heptane, octane, and decane.

6. The method according to claim 5, characterized in that The inert solvent is cumene.

7. The method according to claims 1-7, characterized in that The catalytic oxidation reaction temperature is 60-120° C., and the contact time of the dicyclopentadiene, the oxidant and the titanium silicon molecular sieve catalyst is 1-3 hours.

8. The method according to claim 7, characterized in that The catalytic oxidation reaction is carried out at a pressure of 0.1-1.7 MPa.

9. The method according to claim 1, characterized in that: The organic peroxide oxidant is tert-amyl alcohol hydroperoxide, the molar ratio of dicyclopentadiene to oxidant is 1:1, the amount of the catalyst is 1.3% of the total mass of the dicyclopentadiene, oxidant and inert solvent, the catalytic oxidation reaction temperature is 90° C., the reaction time is 2 hours, and the reaction pressure is 1.0 MPa.

10. The method according to claim 1, characterized in that The organic peroxide oxidant is tert-butyl hydroperoxide, the molar ratio of dicyclopentadiene to oxidant is 3:1, the amount of the catalyst is 2.2% of the total mass of the dicyclopentadiene, oxidant and inert solvent, the catalytic oxidation reaction temperature is 60° C., and the reaction time is 3 hours.

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