A method for synthesizing epoxycyclohexane from cyclohexene by using modified titanium dioxide as a photocatalyst
By using a modified titanium dioxide catalyst to catalyze the synthesis of cyclohexene oxide from cyclohexene under visible light, the problems of low yield and harsh conditions in existing technologies have been solved, achieving efficient and low-cost preparation of cyclohexene oxide, which is suitable for industrial production.
Patent Information
- Application Number
- CN202310784829.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-06-29
- Publication Date
- 2025-11-21
- Estimated Expiration
- 2043-06-29
AI Technical Summary
The yield of cyclohexane oxide in existing technologies is low, the catalytic conditions are harsh, and the photocatalysts have low efficiency under visible light, which limits its industrial application.
A modified titanium dioxide catalyst, specifically a metal phthalocyanine derivative/doped titanium dioxide, is used to catalyze the synthesis of cyclohexene oxide from cyclohexene by reacting with aldehyde co-oxidants and oxygen under visible light.
It improves the conversion rate of cyclohexene and the yield of cyclohexane oxide, with high selectivity, simple operation, low cost, and easy catalyst recovery, making it suitable for industrial applications.
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Figure CN116813570B_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the field of photocatalysis, and particularly relates to a method for synthesizing epoxy cyclohexane by modifying titanium dioxide photocatalysis. BACKGROUND
[0002] Epoxy cyclohexane is a colorless or light yellow liquid with a fragrance, which is insoluble in water, and can be dissolved in volatile substances such as ethanol, acetone and ether, and is an important organic synthesis intermediate in industry. Due to the existence of very active epoxy group in its molecular structure, it is easy to open ring and react with amine, phenol, alcohol, carboxylic acid, water and the like under acidic or alkaline conditions, to generate a series of high-value-added compounds, which can be used for preparing related products such as medicines, pesticides, curing agents, diluents, flame retardants, plasticizers, adhesives and surfactants. It is also a strong organic solvent, which can be used for diluting epoxy resin. Therefore, it has very wide application value.
[0003] In the prior art, epoxy cyclohexane is mainly obtained by recovering from the light oil obtained by fractionation in the process of preparing cyclohexanone and cyclohexanol by oxidizing cyclohexane, and its yield is limited by the yield of the upstream product, thereby restricting the production and development of the downstream products of epoxy cyclohexane.
[0004] In the ordinary chemical synthesis method, cyclohexene epoxidation is used to prepare epoxy cyclohexane, which is a feasible method. In the specific process route, different catalysts can be selected, such as metal porphyrin, metal Schiff base, metal-EDTA, metal pyridine heterocycle, metal phthalocyanine, heteropoly acid and metal salt; different oxidants are selected, in addition to common oxygen and air, TBHP, NaOCl, H2O2, PhIO, NaIO4 and the like are usually used. However, the selectivity of cyclohexene oxidation is complex, and there are two possible oxidation sites, the oxidation site may occur on the double bond or on the allyl group, resulting in low yield of epoxy cyclohexane, and the catalytic conditions are harsh. Therefore, there is an urgent need for a preparation method with high yield and mild conditions.
[0005] After decades of development, photocatalysis in organic synthesis is becoming more and more mature. Mojarrad et al. reported that under the driving of photocatalysis, the complexes of para- or ortho-substituted meso-tetraarylporphyrin and Lewis acid were used as photocatalysts to oxidize olefins, and the best conversion rate of cyclohexene was 93%, and the best conversion rate of cyclooctene was 89%. (Mojarrad AG, et al. European Journal of Inorganic Chemistry, 2017, 21, 2854-2862.) Hosseini-Sarvari M et al. used Pd / ZnO nanoparticles to selectively oxidize styrene to form epoxystyrene under visible light, and the best conversion rate of styrene was 90%, and the best yield of epoxystyrene was 80%. (Hosseini-Sarvari M, et al. Chemistry Select, 2020, 5(28): 8853-8857.) Huang et al. prepared a photocatalyst (CuNPs / TiN) loaded with copper nanosheets (CuNPs) on titanium nitride (TiN), which was not only stable in air, but also could catalyze various olefins under light, and could catalyze styrene in air, with a conversion rate of 100% and a selectivity of epoxystyrene of 89%. (Huang Y, et al. ACS, 2017, 7, 4975-4985.)
[0006] Photocatalytic oxidation is a catalysis that occurs under the action of external light source, which uses semiconductor as catalyst, air, oxygen and the like as oxidant, and light as energy, and has the characteristics of green, strong oxidation, mild reaction conditions and the like. Common photocatalysts include metal oxides, metal sulfides, Bi-based photocatalysts, Ag-based photocatalysts, g-C3N4, metal-organic framework materials and the like, but most of them have a large energy gap, a narrow light response range and only have activity under ultraviolet light, so that the photocatalytic efficiency under visible light is low, and the application in real life is not high. SUMMARY
[0007] The purpose of the present application is to overcome at least one of the defects of the prior art and provide a modified titanium dioxide photocatalytic cyclohexene synthesis method for synthesizing epoxycyclohexane, which has high catalytic efficiency, high yield, high selectivity, high stability and low cost.
[0008] The inventors found that under the catalysis of metal phthalocyanine derivatives / doped titanium dioxide, aldehydes were used as auxiliary oxidants, and under visible light irradiation, cyclohexene was catalyzed by molecular oxygen to prepare epoxycyclohexane, and after optimization of the reaction conditions, the conversion rate of cyclohexene was greater than 90%, and the yield of epoxycyclohexane in the product was greater than 80%, the reaction had high selectivity and was simple to operate.
[0009] The purpose of the present application can be achieved by the following technical solutions:
[0010] A method for synthesizing epoxy cyclohexane by modified titanium dioxide photocatalysis of cyclohexene, comprising the following steps:
[0011] Taking cyclohexene as raw material, adding an oxygen aid, then adding an organic solvent, and then adding a modified titanium dioxide catalyst, and then irradiating with light and passing oxygen during the reaction, and then heating and stirring to obtain epoxy cyclohexane.
[0012] Further, the oxygen aid includes isobutyraldehyde or benzaldehyde.
[0013] Further, the organic solvent includes any one of 1,2-dichloroethane, ethyl acetate or acetonitrile. Among them, 1,2-dichloroethane is an aprotic nonpolar solvent, ethyl acetate is an aprotic weak polar solvent, and acetonitrile is an aprotic strong polar solvent.
[0014] Further, the modified titanium dioxide catalyst is a metal phthalocyanine derivative / doped titanium dioxide catalyst.
[0015] Further, the metal phthalocyanine derivative is sulfonated cobalt phthalocyanine, and the doped titanium dioxide is iron-titanium dioxide. Among them, the metal phthalocyanine derivative is a dye (photosensitizer), and dye sensitization is widely used in the method for preparing photocatalysts, which can expand the catalytic region from the ultraviolet light range to the visible light range. By loading the photosensitizer with strong light absorption performance in the visible light region and matching the energy level structure of the photocatalyst onto the surface of the photocatalyst through physical adsorption or chemical bond combination, the application range is improved. In addition to using metal phthalocyanine derivatives as a load, doped titanium dioxide is also used as a carrier. It is found through experiments that the selectivity of doped titanium dioxide to epoxy cyclohexane is higher than that of pure titanium dioxide, and the use of isobutyraldehyde also greatly improves the conversion rate of cyclohexene and the selectivity of epoxy cyclohexane.
[0016] Further, the preparation method of the metal phthalocyanine derivative / doped titanium dioxide catalyst comprises the following steps:
[0017] Titanium n-butyrate and glacial acetic acid are dissolved in anhydrous ethanol, water is added dropwise, and stirring is continued to form a stable titanium dioxide sol; iron trichloride hexahydrate is dissolved in anhydrous ethanol, and is slowly added dropwise into the prepared titanium dioxide sol, and stirring is continued to obtain a composite semiconductor sol doped with iron ions. After standing and calcination, a titanium dioxide powder doped with iron is obtained, which is denoted as Fe-TiO2.
[0018] Fe-TiO2 is dispersed in a methanol solution to obtain a Fe-TiO2 suspension; a silane coupling agent is added into the methanol solution, and then ammonia is added to obtain a reaction liquid; the Fe-TiO2 suspension is added into the reaction liquid while stirring to obtain Fe-TiO2-NH2; after centrifugation and drying, CoPcS and Fe-TiO2-NH2 are added into water, and then stirring, centrifugation and drying are performed to obtain CoPcS / Fe-TiO2.
[0019] Further, the silane coupling agent is 3-aminopropyl triethoxysilane (APTES).
[0020] Further, the wavelength of the light is 400-800 nm. In the present application, the metal phthalocyanine is introduced as a catalyst to introduce the wavelength of the photocatalysis into the range of visible light, because Fe-TiO2 can be excited at about 400 nm only and has a narrow application range, and the metal phthalocyanine can be excited in the range of visible light, which is 400-800 nm. Therefore, the wavelength of the light is selected to be 400-800 nm, and preferably 400-760 mm.
[0021] Further, the reaction time is 12-27 h, and the reaction temperature is 10-50 ℃.
[0022] Further, the mass ratio between the cyclohexene and the modified titanium dioxide catalyst is 1:(0.015-0.05); the mass ratio between the cyclohexene and the auxiliary oxidant is 1:(0.5-3); the mass ratio between the cyclohexene and the organic solvent is 1:(4-30); and the ratio between the content of the cyclohexene and the flow rate of the oxygen introduced is 1 mol:(800-3500 mL / min).
[0023] Compared with the prior art, the present application has the following advantages:
[0024] (1) The present application uses light as energy and oxygen as an oxidant, and the source of oxygen is extensive and clean, thereby reducing the reaction cost and having the characteristics of greenness, strong oxidizing property and mild reaction conditions.
[0025] (2) The modified titanium dioxide catalyst selected in the present application is a metal phthalocyanine derivative / doped titanium dioxide, the carrier of which is doped titanium dioxide, and CoPcS is loaded on the surface of Fe-TiO2 by aminosilane method.
[0026] (3) The present application uses a metal phthalocyanine derivative / doped titanium dioxide as a catalyst, oxygen as an oxidant and aldehydes as an auxiliary oxidant to catalyze the preparation of cyclohexene oxide from cyclohexene, and the reaction has high catalytic efficiency, high selectivity and high yield of cyclohexene oxide.
[0027] (4) The method for preparing the metal phthalocyanine derivative / doped titanium dioxide is novel, simple in operation, good in loading effect, and the prepared catalyst has high conversion rate of cyclohexene and high selectivity of cyclohexene oxide, the catalyst is easy to separate and recycle, the catalytic effect is still high after multiple uses, the catalyst use cost is greatly reduced, and the method has good industrial application prospect.
[0028] (5) The method has the advantages of green and environmental protection of the oxidant, cheap and easy preparation of the catalyst, easy separation from the product, small dosage of the auxiliary oxidant, mild reaction condition, simple operation and the like, and is a green preparation method of cyclohexene oxide. BRIEF DESCRIPTION OF DRAWINGS
[0029] Figure 1 is the FT-IR diagram of CoPcS / Fe-TiO2 and Fe-TiO2 in Example 1;
[0030] Figure 2 is the UV-VIS diagram of CoPcS / Fe-TiO2 and Fe-TiO2 in Example 1;
[0031] Figure 3 is the scanning electron microscope diagram of Fe-TiO2 in Example 1;
[0032] Figure 4 is the scanning electron microscope diagram of CoPcS / Fe-TiO2 in Example 1. DETAILED DESCRIPTION
[0033] The application will be described in detail below in combination with the drawings and specific examples. The present embodiment is implemented on the premise of the technical scheme of the present application, and detailed implementation modes and specific operation processes are given, but the protection scope of the present application is not limited to the following examples.
[0034] Example 1
[0035] I. Preparation method of CoPcS / Fe-TiO2 catalyst
[0036] 17g of n-butyl titanate and 5g of glacial acetic acid were weighed and dissolved in 25g of anhydrous ethanol, 1g of water was added dropwise and stirring was continued for 1h to form a stable titanium dioxide sol. Then 0.2g of iron trichloride hexahydrate was weighed and dissolved in 10g of anhydrous ethanol, which was slowly added dropwise into the prepared titanium dioxide sol, and stirring was continued for 1h to obtain a composite semiconductor sol doped with iron ions. After standing for 1d, it was placed in a 500℃ muffle furnace for 3h to obtain iron-doped titanium dioxide powder.
[0037] 0.2 g of Fe-TiO2 nanoparticles were added to 15 g of methanol solution to prepare a Fe-TiO2 suspension. Then, 2 g of APTES was added to 15 g of methanol solution, followed by 2 g of ammonia water to prepare a reaction solution. The Fe-TiO2 suspension was added dropwise to the reaction solution under vigorous stirring for 24 h to form Fe-TiO2-NH2. After centrifugation and drying, distilled water was added to form a Fe-TiO2-NH2 aqueous solution. Then, 0.02 g of CoPcS was added to the Fe-TiO2-NH2 aqueous solution, and the mixture was stirred in the dark for 2 h. Finally, the mixture was centrifuged and vacuum dried at 80 °C to obtain the CoPcS / Fe-TiO2 catalyst.
[0038] In this embodiment, the structures of Fe-TiO2 and CoPcS / Fe-TiO2 were characterized using FT-IR. Figure 1 It can be seen that both Fe-TiO2 and CoPcS / Fe-TiO2 have 459, 1626, and 3430 cm⁻¹ values. -1 The absorption peaks are around 459 cm⁻¹. -1 The absorption peaks correspond to the stretching vibrations of Ti-O-Fe, while the peaks at 1626 and 3430 cm⁻¹ correspond to the stretching vibrations of Ti-O-Fe. -1 The absorption peaks correspond to the bending and stretching vibrations of the -OH group, indicating that the sample contains moisture and may not have been completely dried during testing. In the infrared spectrum of CoPcS / Fe-TiO2, peaks at 730, 756, 782, 1230, 1320, 1376, and 2923 cm⁻¹ were also observed. -1 The absorption peaks are at 730, 756, and 782 cm⁻¹. -1 The absorption peaks are those of the phthalocyanine ring, at 1230 and 1320 cm⁻¹. -1 The absorption peak corresponds to the CN and C C bonds on the phthalocyanine ring, at 1376 cm⁻¹. -1 The absorption peak at 2923 cm⁻¹ is a characteristic absorption peak of the O=S=O stretching vibration of the sulfonic acid group. -1 The absorption peak at that point corresponds to the stretching vibration of the CH bond, confirming the structure of CoPcS and indicating that CoPcS has been loaded onto Fe-TiO2.
[0039] In this embodiment, the structures of CoPcS and CoPcS / Fe-TiO2 were also characterized using ultraviolet-visible absorption spectroscopy. According to the literature (Mugadza T, Nyokong T. Electrochimica Acta. 2009, 54(26): 6347-6353.), metal phthalocyanines and their complexes have absorption peaks in the ultraviolet region of 300-400 nm and the visible region of 600-800 nm. Figure 2UV-Vis absorption spectra of CoPcS and CoPcS / Fe-TiO2 after dissolving in DMSO. CoPcS has maximum absorption wavelength at about 354 nm and 673 nm, while CoPcS / Fe-TiO2 also has maximum absorption wavelength at about 355 nm and 672 nm, indicating that CoPcS has been successfully loaded on the surface of Fe-TiO2.
[0040] In this embodiment, the structure of Fe-TiO2 and CoPcS / Fe-TiO2 was also characterized by SEM. Figure 3 Scanning electron microscope image of Fe-TiO2 at 10000 times magnification, Figure 4 Scanning electron microscope image of CoPcS / Fe-TiO2 at 10000 times magnification. From Figure 3 it can be observed that there are some particles on the surface of TiO2, and they are firmly attached, indicating that iron ions have successfully entered the interior of TiO2. From Figure 4 it can be observed that there are larger particles on the surface of Fe-TiO2, and they are firmly attached, indicating that sulfonated cobalt phthalocyanine has been successfully loaded on the surface of Fe-TiO2.
[0041] II. Synthesis of cyclohexene oxide from cyclohexene
[0042] In two reaction tubes, 0.03 g of catalyst (CoPcS / Fe-TiO2), 0.8 g of cyclohexene, 1.6 g of isobutyraldehyde, and 8 g of acetonitrile were added in sequence, and irradiation was performed with visible light of 620 nm wavelength. Then, oxygen was introduced at a flow rate of 20 mL / min under normal pressure, and constant temperature stirring was carried out at 30°C for 18 h. Finally, GC detection analysis was performed, and the conversion rate of cyclohexene was 80.11%, and the yield of cyclohexene oxide was 59.92%.
[0043] The ratio of cyclohexene, isobutyraldehyde, and acetonitrile used was calculated by mass ratio, i.e. cyclohexene:isobutyraldehyde:acetonitrile = 1:2:10; the addition amount of catalyst was calculated by mass ratio of cyclohexene to catalyst, i.e. cyclohexene:catalyst = 1:0.0375; the oxygen flow rate was calculated by oxygen flow rate per 1 mol of cyclohexene, i.e. 2050 mL / min.
[0044] Example 2
[0045] In this embodiment, the preparation process of CoPcS / Fe-TiO2 catalyst was consistent with that of Example 1.
[0046] In two reaction tubes, 0.03 g of catalyst (CoPcS / Fe-TiO2), 0.8 g of cyclohexene, 1.6 g of isobutyraldehyde, and 12 g of 1,2-dichloroethane were sequentially added, visible light with a wavelength of 670 nm was used for irradiation, then oxygen was introduced at a flow rate of 20 mL / min under normal pressure, constant temperature stirring was carried out at 30°C for 18 h, and finally GC detection analysis was performed, the conversion rate of cyclohexene was 65.63%, and the yield of cyclohexene oxide was 51.57%.
[0047] The ratio of cyclohexene, isobutyraldehyde, and 1,2-dichloroethane used was calculated according to the mass ratio, i.e., cyclohexene:isobutyraldehyde:1,2-dichloroethane was 1:2:15; the addition amount of catalyst was calculated according to the mass ratio of cyclohexene to catalyst, i.e., cyclohexene:catalyst was 1:0.0375; the oxygen flow rate was calculated according to the oxygen flow rate of 2050 mL / min per 1 mol of cyclohexene.
[0048] Example 3
[0049] In this embodiment, the preparation process of the CoPcS / Fe-TiO2 catalyst was consistent with that of Example 1.
[0050] In two reaction tubes, 0.03 g of catalyst (CoPcS / Fe-TiO2), 0.8 g of cyclohexene, 1.6 g of isobutyraldehyde, and 12 g of 1,2-dichloroethane were sequentially added, visible light with a wavelength of 670 nm was used for irradiation, then oxygen was introduced at a flow rate of 20 mL / min under normal pressure, constant temperature stirring was carried out at 30°C for 18 h, and finally GC detection analysis was performed, the conversion rate of cyclohexene was 65.63%, and the yield of cyclohexene oxide was 51.57%.
[0051] The ratio of cyclohexene, isobutyraldehyde, and 1,2-dichloroethane used was calculated according to the mass ratio, i.e., cyclohexene:isobutyraldehyde:1,2-dichloroethane was 1:2:15; the addition amount of catalyst was calculated according to the mass ratio of cyclohexene to catalyst, i.e., cyclohexene:catalyst was 1:0.0375; the oxygen flow rate was calculated according to the oxygen flow rate of 2050 mL / min per 1 mol of cyclohexene.
[0052] Example 4
[0053] In this embodiment, the preparation process of the CoPcS / Fe-TiO2 catalyst was consistent with that of Example 1.
[0054] In two reaction tubes, 0.03 g of catalyst (CoPcS / Fe-TiO2), 0.8 g of cyclohexene, 1.6 g of isobutyraldehyde, and 12 g of 1,2-dichloroethane were sequentially added, visible light with a wavelength of 670 nm was used for irradiation, then oxygen was introduced at a flow rate of 20 mL / min under normal pressure, constant temperature stirring was carried out at 30°C for 18 h, and finally GC detection analysis was performed, the conversion rate of cyclohexene was 65.63%, and the yield of cyclohexene oxide was 51.57%.
[0055] The ratio of cyclohexene, isobutyraldehyde and acetonitrile used is calculated by mass ratio, i.e. cyclohexene: isobutyraldehyde: acetonitrile = 1:2:10; the amount of catalyst added is calculated by mass ratio of cyclohexene to catalyst, i.e. cyclohexene: catalyst = 1:0.03125; the oxygen flow is calculated by oxygen flow per 1 mol of cyclohexene, which is 2050 mL / min.
[0056] Example 5
[0057] In this example, the preparation process of the CoPcS / Fe-TiO2 catalyst is consistent with that of Example 1.
[0058] In two reaction tubes, 0.025 g of catalyst (CoPcS / Fe-TiO2), 0.8 g of cyclohexene, 1.6 g of isobutyraldehyde and 8 g of acetonitrile were sequentially added, irradiated with visible light of 670 nm wavelength, then oxygen was introduced at a flow rate of 20 mL / min under normal pressure, and stirred at a constant temperature of 25°C for 21 h. Finally, GC detection analysis showed that the conversion rate of cyclohexene was 88.56% and the yield of epoxycyclohexane was 77.01%.
[0059] The ratio of cyclohexene, isobutyraldehyde and acetonitrile used is calculated by mass ratio, i.e. cyclohexene: isobutyraldehyde: acetonitrile = 1:2:10; the amount of catalyst added is calculated by mass ratio of cyclohexene to catalyst, i.e. cyclohexene: catalyst = 1:0.03125; the oxygen flow is calculated by oxygen flow per 1 mol of cyclohexene, which is 2050 mL / min.
[0060] Example 6
[0061] In this example, the preparation process of the CoPcS / Fe-TiO2 catalyst is consistent with that of Example 1.
[0062] In two reaction tubes, 0.025 g of catalyst (CoPcS / Fe-TiO2), 0.8 g of cyclohexene, 1.6 g of isobutyraldehyde and 8 g of acetonitrile were sequentially added, irradiated with visible light of 670 nm wavelength, then oxygen was introduced at a flow rate of 20 mL / min under normal pressure, and stirred at a constant temperature of 25°C for 21 h. Finally, GC detection analysis showed that the conversion rate of cyclohexene was 88.56% and the yield of epoxycyclohexane was 77.01%.
[0063] The ratio of cyclohexene, isobutyraldehyde and acetonitrile used is calculated by mass ratio, i.e. cyclohexene: isobutyraldehyde: acetonitrile = 1:2:10; the amount of catalyst added is calculated by mass ratio of cyclohexene to catalyst, i.e. cyclohexene: catalyst = 1:0.03125; the oxygen flow is calculated by oxygen flow per 1 mol of cyclohexene, which is 2050 mL / min.
[0064] Example 7
[0065] The CoPcS / Fe-TiO2 catalyst was prepared according to the method of Example 1.
[0066] In two reaction tubes, 0.025 g of catalyst (CoPcS / Fe-TiO2), 0.8 g of cyclohexene, 1.2 g of isobutyraldehyde, and 8 g of acetonitrile were sequentially added, and irradiation was performed using visible light with a wavelength of 670 nm. Then, oxygen was introduced at a flow rate of 30 mL / min under normal pressure, and constant temperature stirring was performed at 25°C for 21 h. Finally, GC detection analysis was performed, and the conversion rate of cyclohexene was 90.22%, and the yield of cyclohexene oxide was 76.09%.
[0067] The ratio of cyclohexene, isobutyraldehyde, and acetonitrile used was calculated according to the mass ratio, i.e., cyclohexene:isobutyraldehyde:acetonitrile was 1:1.5:10; the amount of catalyst added was calculated according to the mass ratio of cyclohexene to catalyst, i.e., cyclohexene:catalyst was 1:0.03125; and the oxygen flow rate was calculated according to the oxygen flow rate per 1 mol of cyclohexene, which was 3075 mL / min.
[0068] The above description is only a preferred embodiment of the present application, and is not intended to limit the present application in other forms. Any person skilled in the art can modify or change the above-mentioned technical content into equivalent embodiments. However, any simple modification, equivalent change, and modification of the above-mentioned embodiments, which do not deviate from the technical solution of the present application, and which are based on the technical essence of the present application, still belong to the protection scope of the present application.
Claims
1. A method for synthesizing cyclohexene oxide from cyclohexene using photocatalysis with modified titanium dioxide, characterized in that, Includes the following steps: Cyclohexene was used as a raw material. In the presence of an oxygen-providing agent, an organic solvent was added, followed by the addition of a modified titanium dioxide catalyst. During the reaction, the mixture was irradiated with light and oxygen was introduced. The reaction was heated and stirred to obtain cyclohexane oxide. The modified titanium dioxide catalyst is a metal phthalocyanine derivative / doped titanium dioxide catalyst; The metal phthalocyanine derivative is sulfonated cobalt phthalocyanine, and the doped titanium dioxide is iron-titanium dioxide; The preparation method of the metal phthalocyanine derivative / doped titanium dioxide catalyst includes the following steps: Weigh out tetrabutyl titanate and glacial acetic acid and dissolve them in anhydrous ethanol. Add water dropwise and continue stirring to form a stable titanium dioxide sol. Weigh out ferric chloride hexahydrate and dissolve it in anhydrous ethanol. Add it dropwise to the prepared titanium dioxide sol and continue stirring to obtain an iron-doped composite semiconductor sol. After standing and calcining, iron-doped titanium dioxide powder is obtained, denoted as Fe-TiO2. Fe-TiO2 was dispersed in a methanol solution to obtain a Fe-TiO2 suspension; a silane coupling agent was added to the methanol solution, followed by ammonia to obtain a reaction solution; the Fe-TiO2 suspension was added to the reaction solution while stirring to obtain Fe-TiO2-NH2; after centrifugation and drying, CoPcS and Fe-TiO2-NH2 were added to water, and after stirring, centrifugation, and drying, CoPcS / Fe-TiO2 was obtained; The silane coupling agent is 3-aminopropyltriethoxysilane.
2. The method for synthesizing cyclohexene oxide from modified titanium dioxide via photocatalysis according to claim 1, characterized in that, The oxygen-providing agents include isobutyraldehyde or benzaldehyde.
3. The method for synthesizing cyclohexene oxide from modified titanium dioxide via photocatalysis according to claim 1, characterized in that, The organic solvent includes any one of 1,2-dichloroethane, ethyl acetate, or acetonitrile.
4. The method for synthesizing cyclohexene oxide from modified titanium dioxide via photocatalysis according to claim 1, characterized in that, The wavelength of the light is 400–800 nm.
5. The method for synthesizing cyclohexene oxide from modified titanium dioxide via photocatalysis according to claim 1, characterized in that, The reaction time is 12–27 h; the reaction temperature is 10–50 °C.
6. The method for synthesizing cyclohexene oxide from modified titanium dioxide via photocatalysis according to claim 1, characterized in that, The mass ratio of cyclohexene to the modified titanium dioxide catalyst is 1: (0.015~0.05); The mass ratio of cyclohexene to the pro-oxidant is 1:(0.5-3); The mass ratio between the cyclohexene and the organic solvent is 1:(4-30); The ratio between the cyclohexene content and the oxygen flow rate is 1 mol: (800-3500 mL / min).