A method for preparing cyclohexenone by high-selectivity oxidation of cyclohexene using a rare earth-based perovskite
By mixing rare earth-based perovskite catalysts with cyclohexene and a liquid medium in a photoreactor, introducing oxygen, and stirring under light, the problems of environmental unfriendliness and harsh reaction conditions in existing cyclohexene oxidation methods are solved. This method achieves highly selective and high-conversion cyclohexenone preparation, which is suitable for large-scale production.
Patent Information
- Application Number
- CN202311713733.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-12-14
- Publication Date
- 2026-01-30
- Estimated Expiration
- 2043-12-14
AI Technical Summary
Existing methods for preparing cyclohexenone by cyclohexene oxidation have problems such as being not environmentally friendly enough, having unmild reaction conditions, or having long reaction times.
Rare earth-based perovskite catalysts are mixed with cyclohexene and liquid reaction medium in a photoreactor, and oxygen is introduced as an oxidant. The reaction is carried out under light and stirring conditions. The reaction temperature, time and light source are optimized, oxygen is selectively introduced, and the catalyst is separated and recycled after the reaction.
The method achieves highly selective oxidation of cyclohexene to cyclohexenone under low-temperature and pressureless conditions, with high cyclohexene conversion, good selectivity, and high catalyst stability. It is suitable for large-scale production, is environmentally friendly, and has low cost.
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Abstract
Description
Technical Field
[0001] This invention relates to the field of cyclohexene oxidation to cyclohexenone technology, specifically a method for the highly selective oxidation of cyclohexene to cyclohexenone using rare earth-based perovskites. Background Technology
[0002] The catalytic oxidation of alkenes to produce high-value-added oxygen-containing derivatives is a fundamental reaction in organic chemistry. The resulting products are valuable and abundant commercial intermediates that can undergo further reactions. In particular, the allyl oxidation of cyclohexene, a representative of cycloalkenes, is crucial. Cyclohexene is an inexpensive, abundant, and readily available industrial raw material, primarily produced through the selective hydrogenation of benzene. Although cyclohexene has a simple chemical structure, its molecular structure contains two oxidation sites: the allyl CH bond and the C=C bond, leading to a complex distribution of oxidation products. Oxidation of cyclohexene at the allyl CH bond produces a 2-cyclohexen-1-hydroperoxide intermediate, which then decomposes into 2-cyclohexen-1-ol or dehydrates to 2-cyclohexen-1-one. Simultaneously, oxidation of the C=C bond produces cyclohexane oxide, which hydrolyzes to cyclohexane-1,2-diol. Further oxidation of cyclohexane-1,2-diol leads to adipic acid through ring-opening. Among them, the generated cyclohexenone is an important fine chemical intermediate with high industrial value and is widely used in fragrances, pharmaceuticals, pesticides, surfactants, polymer materials and other fields.
[0003] Traditional oxidants for cyclohexene oxidation typically include iodobenzene, sodium hypochlorite, and chromium trioxide. While these strong oxidants can improve product yield, their application is limited by high cost, inconvenient transportation, explosiveness, environmental pollution, and low atom economy. Therefore, developing green processes for catalytic oxidation of cyclohexene is becoming increasingly important. In recent years, several green oxidants have been applied to the oxidation of cyclohexene, including molecular oxygen (O2), tert-butyl hydroperoxide (TBHP), and hydrogen peroxide (H2O2). Among these oxidants, H2O2 is produced industrially through anthraquinone oxidation, which is difficult to consider a green route because it requires high energy input and generates a large amount of waste. Since TBHP is a product of the reaction between tert-butanol and H2O2 in acidic solution, it is subject to environmental limitations, similar to H2O2. Molecular oxygen, due to its low price, abundant reserves, and environmental friendliness, has received widespread attention in academic research and industrial applications.
[0004] Currently, the selective controlled oxidation of cyclohexene has been extensively studied. Existing catalysts for the catalytic oxidation of cyclohexene include complex catalysts, noble metal catalysts, heteropolyacid catalysts, and molecular sieve catalysts.
[0005] (1) Complex catalyst (ACS Applied Materials & Interfaces, 2020, 12(20): 23060-23075.): Kosari et al. converted mesoporous aluminum silica spheres into submicron aluminum silica copper hollow spheres by a one-pot hydrothermal method, and used them to catalyze the oxidation of cyclohexene. The reaction temperature was 70℃, TBHP was used as the oxidant, and the reaction time was 12 hours. The reaction process is as follows:
[0006]
[0007] This method achieves a cyclohexene conversion rate of 92.1% and a selectivity of 70.3% for cyclohexenone. However, the main drawback of this reaction system is the use of TBHP as an oxidant, which is not environmentally friendly.
[0008] (2) Noble Metal Catalysts (Materials Chemistry and Physics, 2018, 213:472-481.): Kohantorabi et al. successfully synthesized a flower-like core-shell structured Fe3O4@Au / metal-organic framework (Fe3O4@Au / MOF) nanocomposite material via hydrothermal synthesis and tested its catalytic performance. The reaction was carried out at 80℃ and 13 bar O2 for 18 h, and the reaction process is as follows:
[0009]
[0010] This method achieves a cyclohexene conversion of 58% and a cyclohexenone selectivity of 90%. The main drawbacks of this catalytic system are its uneconomical nature and long processing time.
[0011] (3) Heteropolyacid catalysts (Industrial & Engineering Chemistry Research, 2021, 61(1):299-306.): Wu et al. prepared a novel heteropolyacid-based polymer as a heterogeneous catalyst for the oxidation of cyclohexene allyl using molecular oxygen as an oxidant. The catalyst exhibited good activity and selectivity. The reaction was carried out at 130℃ and 8 bar O2 for 6 h. The reaction process is as follows:
[0012]
[0013] The method achieved a cyclohexene conversion rate of 85.7% and a selectivity for cyclohexenone of 51.9%, with no significant loss of activity or selectivity after five repetitions. The main drawback of this catalytic reaction system is the high temperature and high pressure.
[0014] (4) Molecular sieve catalysts (Applied Catalysis A:General, 2008, 346(1-2):112-116.): Dapurkar et al. used mesoporous CrMCM-41 molecular sieve catalysts to carry out mild oxidation of cycloolefins under 1 atm O2 and 70 °C conditions without organic solvents for 24 hours. The reaction process is as follows:
[0015]
[0016] This method achieves a cyclohexene conversion rate of 52.2% and a selectivity for cyclohexenone of 71.2%. The main drawback of this catalytic system is its long reaction time.
[0017] In summary, the current research direction for the catalytic oxidation of cyclohexene to cyclohexenone is to achieve a greener and pollution-free preparation process by using environmentally friendly catalysts, reacting at lower temperatures for shorter times, without the participation of auxiliary agents. This process also aligns with the needs of green chemistry and national development. Summary of the Invention
[0018] The purpose of this invention is to provide a method for the highly selective oxidation of cyclohexene to cyclohexenone using rare earth-based perovskites, in order to solve the problems of existing methods being either not environmentally friendly enough, having unmild reaction conditions, or having long reaction times.
[0019] To achieve the above objectives, the present invention provides the following technical solution: a method for the highly selective oxidation of cyclohexene to cyclohexenone using rare earth-based perovskite, comprising adding cyclohexene, a rare earth-based perovskite catalyst and a liquid-phase reaction medium to a photoreaction tube, heating the resulting mixture to 60-80°C and maintaining the temperature, intermittently introducing oxygen as an oxidant, and reacting fully under light and stirring conditions to obtain the product.
[0020] To obtain the best reactant conversion rate and selectivity for cyclohexenone, the reaction time is preferably 12 hours.
[0021] Specifically, the general chemical formula of the above-mentioned rare earth-based perovskite catalyst is ABO3, where A is a rare earth element and B is a transition metal element; the molar ratio of cyclohexene to catalyst added in the photoreactor is 1:(0.01~0.05).
[0022] To obtain optimal reactant conversion and selectivity for cyclohexenone, the catalyst is further preferably La2Co. 1.4 Cu 0.6 O6 or La2Co 1.6 Cu 0.4 O6.
[0023] Preferably, the above-mentioned liquid-phase reaction medium is acetonitrile; the ratio of cyclohexene to acetonitrile added to the photoreaction tube is 1 mol:(1-3 L).
[0024] Preferably, the above-mentioned method of intermittent oxygen introduction involves introducing oxygen for several seconds at regular intervals, with the oxygen flow rate controlled at 10-16 ml / min.
[0025] Alternatively, in the above preferred embodiment, oxygen can be introduced for 60 seconds every 30 minutes.
[0026] To obtain the best reactant conversion rate and selectivity for cyclohexenone, preferably, the above illumination uses a xenon lamp as the light source, and the illumination is a 420nm cutoff light.
[0027] The above product is filtered or centrifuged, and the liquid portion is separated by evaporation or crystallization to obtain cyclohexenone. In a preferred scheme, the cyclohexene conversion rate can reach 89.4%, and the selectivity for cyclohexenone can reach 72.2%.
[0028] Preferably, after the above product is filtered or centrifuged, the catalyst in the solid part is recycled for five more reactions, and the catalytic activity and selectivity do not decrease significantly.
[0029] Compared with the prior art, the beneficial effects of the present invention are:
[0030] 1. The method for using rare earth-based perovskite to produce cyclohexenone with high selectivity of cyclohexene is simple and convenient to operate. Catalytic oxidation can be completed in a short time under mild reaction conditions with low temperature and no pressure required. The reaction process is green and mild. The conversion rate of cyclohexene is greatly improved by light irradiation. The selectivity for cyclohexenone is also high. The production cost is low and it is suitable for large-scale production.
[0031] 2. The method for using rare earth-based perovskite to produce cyclohexenone with high selectivity of cyclohexene employs a rare earth-based perovskite catalyst, which has high activity for selective oxidation of cyclohexene. The raw materials are cheap and readily available, and the preparation process is simple and environmentally friendly. In this invention, the rare earth-based perovskite catalyst has relatively stable activity, and its activity and selectivity do not decrease significantly after being recycled 5 times.
[0032] 3. The method for using this rare earth-based perovskite to produce cyclohexenone through highly selective oxidation of cyclohexene uses oxygen as an oxidant, which is green, environmentally friendly, economical and efficient. Detailed Implementation
[0033] A method for the highly selective oxidation of cyclohexene to cyclohexenone using rare earth-based perovskites includes:
[0034] Cyclohexene, rare earth-based perovskite catalyst, and liquid-phase reaction medium were added to the photoreaction tube;
[0035] The resulting mixture was heated to 60–80°C and maintained at that temperature, while oxygen was intermittently introduced.
[0036] The product is obtained by reacting under illumination and stirring conditions, with a preferred reaction time of 12 hours. Xenon lamps can be used as the light source for illumination. When using 420nm cutoff light, the conversion rate of cyclohexene and the selectivity for cyclohexenone are better. Good results can also be obtained under certain single wavelengths of light above 420nm. Alternatively, a wavelength range above 420nm can be selected, such as 600-800nm, to obtain good results. The specific stirring speed has little impact on this method, and 1000rpm can be used as a reference.
[0037] The catalyst added to the photoreactor has the specific chemical formula ABO3 (i.e., ABX3, where theoretically X can be an anion with a small atomic radius, such as oxygen). This formula should be understood to include positive integer multiples thereof, as is well known to those skilled in the art, such as bis-perovskite A2B. x C 2-x 06, triperovskite A3B2C1O9, etc., where A is a rare earth element and B is a transition metal element. The C in the aforementioned diperovskite and triperovskite is also a transition metal element, just like B. x is 0–2. The molar ratio of cyclohexene to catalyst added to the photoreactor can be further optimized to 1:(0.01–0.05). More preferably, the catalyst is La2Co. 1.4 Cu 0.6 O6 or La2Co 1.6 Cu 0.4 Based on extensive experimental results, the conversion rate of cyclohexene by these two catalysts can reach about 90%, and the selectivity for cyclohexenone can exceed 70%. Of course, other catalysts can achieve this effect, or even exceed it, but only the better option is provided here.
[0038] The catalysts mentioned above can be purchased directly from the market or prepared using various existing methods, such as the sol-gel method. For specific details, please refer to the following steps: Weigh the required stoichiometric amount of metal nitrate, add an appropriate amount of deionized water, stir until the mixture becomes a clear solution, add citric acid complexing agent, and after the citric acid is completely dissolved, add urea to obtain a mixture. Stir at 80°C and 700 rpm until a gel state is reached, and then place it in an oven to dry at 180°C for 12 hours. After drying, grind the obtained solid sol, and calcine the resulting powder at 650°C for 4 hours to obtain the catalyst.
[0039] The preferred liquid reaction medium added to the photoreaction tube is acetonitrile, and the ratio of cyclohexene to acetonitrile added to the photoreaction tube can be further preferred to be 1 mol:(1-3 L). Acetonitrile has excellent solvent properties, can dissolve a variety of organic, inorganic and gaseous substances, has high stability, is environmentally friendly, and is a renewable resource. In addition to acetonitrile, methanol, ethanol or other solvents that can dissolve cyclohexene and its oxides well can also be used as substitutes.
[0040] In addition, the intermittent introduction of oxygen during the reaction is used as an oxidant for reference. Specifically, oxygen can be introduced for several seconds at regular intervals, and the flow rate of oxygen can be further controlled to 10-16 ml / min, for example, oxygen can be introduced for 60 seconds every 30 minutes.
[0041] The product obtained by the method of the present invention can be separated into solid and liquid parts by filtration or centrifugation. The solid part is the catalyst. After experimental testing, it was found that after recycling this part of the catalyst for five reactions of the present invention, the catalytic activity and selectivity did not decrease significantly, thus saving a lot of catalyst preparation or purchase costs. The liquid part after solid-liquid separation can be separated into cyclohexenone by simple evaporation or crystallization. Of course, it can also be separated by commonly used methods in the chemical industry, such as vacuum distillation. The remaining solvent after separation can also be recycled to further improve the green and environmentally friendly characteristics of this method.
[0042] In a preferred embodiment provided by the following embodiments of the present invention, the cyclohexene conversion rate can reach 89.4%, the selectivity for cyclohexenone reaches 72.2%, and compared with the existing catalytic oxidation methods of cyclohexene, the present invention is carried out under mild conditions with lower temperature and no pressure, the oxidant is green and environmentally friendly, the preparation time is shorter, and the economy is better, so it is easy to apply to large-scale production.
[0043] The following are embodiments of the present invention, which are provided to better understand the preferred solutions of the present invention. These embodiments are intended to illustrate, rather than limit, the scope of the present invention.
[0044] Example 1:
[0045] Cyclohexene (3 mmol), acetonitrile (5 mL), and La2CoCuO6 were added to a 10 mL photoreaction tube. Oxygen was intermittently introduced, and the reaction mixture was reacted at 60-80 °C under 420 nm cutoff light for 12 h. After the reaction was completed, the cyclohexene conversion rate was 67.5% and the selectivity was 75.1% by GC analysis.
[0046] Example 2:
[0047] Add cyclohexene (3 mmol), acetonitrile (5 mL), and La2Co to a 10 mL photoreaction tube. 1.2Cu 0.8 O6 was intermittently introduced, and the reaction mixture was reacted at 60-80℃ under 420nm cutoff light for 12 hours. After the reaction was completed, GC analysis showed that the cyclohexene conversion rate was 69.9% and the selectivity was 59.6%.
[0048] Example 3:
[0049] Add cyclohexene (3 mmol), acetonitrile (5 mL), and La2Co to a 10 mL photoreaction tube. 1.4 Cu 0.6 O6 was intermittently introduced, and the reaction mixture was reacted at 60-80℃ under 420nm cutoff light for 12 hours. After the reaction was completed, GC analysis showed that the cyclohexene conversion rate was 89.4% and the selectivity was 72.2%.
[0050] Example 4:
[0051] Add cyclohexene (3 mmol), acetonitrile (5 mL), and La2Co to a 10 mL photoreaction tube. 1.6 Cu 0.4 O6 was intermittently introduced, and the reaction mixture was reacted at 60-80℃ under 420nm cutoff light for 12 hours. After the reaction was completed, GC analysis showed that the cyclohexene conversion rate was 71.2% and the selectivity was 68.6%.
[0052] Example 5:
[0053] Add cyclohexene (3 mmol), acetonitrile (5 mL), and La2Co to a 10 mL photoreaction tube. 1.8 Cu 0.2 O6 was intermittently introduced, and the reaction mixture was reacted at 60-80℃ under 420nm cutoff light for 12 hours. After the reaction was completed, GC analysis showed that the cyclohexene conversion rate was 68% and the selectivity was 55.8%.
[0054] Example 6:
[0055] Cyclohexene (3 mmol), acetonitrile (5 mL), and LaCoO3 were added to a 10 mL photoreaction tube. Oxygen was intermittently introduced, and the reaction mixture was reacted for 12 h at 60-80 °C under 420 nm cutoff light. After the reaction was completed, the cyclohexene conversion rate was 71.4% and the selectivity was 68.0% by GC analysis.
[0056] Example 7:
[0057] Cyclohexene (3 mmol), acetonitrile (5 mL), and LaCuO3 were added to a 10 mL photoreaction tube. Oxygen was intermittently introduced, and the reaction mixture was reacted for 12 h at 60-80 °C under 420 nm cutoff light. After the reaction was completed, the cyclohexene conversion rate was 60.3% and the selectivity was 66.7% by GC analysis.
[0058] Example 8:
[0059] Cyclohexene (3 mmol), acetonitrile (5 mL), and La2CoNiO6 were added to a 10 mL photoreaction tube. Oxygen was intermittently introduced, and the reaction mixture was reacted at 60-80 °C under 420 nm cutoff light for 12 h. After the reaction was completed, the cyclohexene conversion rate was 69.5% and the selectivity was 78.2% by GC.
[0060] Example 9:
[0061] Cyclohexene (3 mmol), acetonitrile (5 mL), and LaNiO3 were added to a 10 mL photoreaction tube. Oxygen was intermittently introduced, and the reaction mixture was reacted for 12 h at 60-80 °C under 420 nm cutoff light. After the reaction was completed, the cyclohexene conversion rate was 76.1% and the selectivity was 70.5% by GC analysis.
[0062] Example 10:
[0063] Add cyclohexene (3 mmol), acetonitrile (5 mL), and La2Co to a 10 mL photoreaction tube. 1.4 Cu 0.6 O6 was intermittently introduced, and the reaction mixture was reacted at 60-80℃ in the dark for 12 hours. After the reaction was completed, GC analysis showed that the cyclohexene conversion rate was 33.6% and the selectivity was 71.2%.
[0064] Compared with Example 3, this example lacks light conditions, which greatly affects the conversion rate of cyclohexene, but the selectivity of the product is still good.
[0065] Example 11:
[0066] Add cyclohexene (3 mmol), acetonitrile (5 mL), and La2Co to a 10 mL photoreaction tube. 1.4 Cu 0.6 O6 was intermittently introduced, and the reaction mixture was reacted at 40-50℃ under 420nm cutoff light for 3 hours. After the reaction was completed, GC analysis showed that the cyclohexene conversion rate was 21.0% and the selectivity was 59.7%.
[0067] Compared with Example 3, the reaction temperature in this example is significantly reduced, and the conversion rate of cyclohexene and the selectivity of the product are both significantly reduced.
[0068] Example 12:
[0069] Add cyclohexene (3 mmol), acetonitrile (5 mL), and La2Co to a 10 mL photoreaction tube. 1.4 Cu 0.6 O6 was intermittently introduced, and the reaction mixture was reacted at 50-60℃ under 420nm cutoff light for 1 hour. After the reaction was completed, GC analysis showed that the cyclohexene conversion rate was 18.6% and the selectivity was 59.1%.
[0070] Compared with Example 3, this example has a lower reaction temperature, a significantly reduced reaction time, and a significant decrease in both cyclohexene conversion and product selectivity.
[0071] Example 13:
[0072] Add cyclohexene (3 mmol), acetonitrile (5 mL), and La2Co to a 10 mL photoreaction tube. 1.4 Cu 0.6 O6 was intermittently introduced, and the reaction mixture was reacted at 60-80℃ under 420nm cutoff light for 1 hour. After the reaction was completed, GC analysis showed that the cyclohexene conversion rate was 21.6% and the selectivity was 59.3%.
[0073] Compared with Example 3, this example only significantly reduces the reaction time, and the cyclohexene conversion rate and product selectivity are both significantly reduced. However, compared with Example 12, the reaction temperature is higher, and the cyclohexene conversion rate is slightly improved.
[0074] Example 14:
[0075] Add cyclohexene (3 mmol), acetonitrile (5 mL), and La2Co to a 10 mL photoreaction tube. 1.4 Cu 0.6 O6 was intermittently introduced, and the reaction mixture was irradiated with light at 60-80℃ and a wavelength of 500nm for 12 hours. After the reaction was completed, GC analysis showed that the cyclohexene conversion rate was 39.8% and the selectivity was 68.6%.
[0076] Compared with Example 3, this embodiment uses a single 500nm light source, which significantly reduces the cyclohexene conversion rate and slightly decreases the product selectivity.
[0077] Example 15:
[0078] Add cyclohexene (3 mmol), acetonitrile (5 mL), and La2Co to a 10 mL photoreaction tube.1.4 Cu 0.6 O6 was intermittently introduced, and the reaction mixture was irradiated with light at 60-80℃ and a wavelength of 600nm for 12 hours. After the reaction was completed, GC analysis showed that the cyclohexene conversion rate was 51.6% and the selectivity was 76.4%.
[0079] Compared with Example 3, this embodiment uses a single 600nm light source, which significantly reduces the cyclohexene conversion rate, but improves the product selectivity.
[0080] Example 16:
[0081] Add cyclohexene (3 mmol), acetonitrile (5 mL), and La2Co to a 10 mL photoreaction tube. 1.4 Cu 0.6 O6 was intermittently introduced, and the reaction mixture was irradiated with light at 60-80℃ and a wavelength of 700nm for 12 hours. After the reaction was completed, GC analysis showed that the cyclohexene conversion rate was 61.2% and the selectivity was 84.4%.
[0082] Compared with Example 3, this embodiment uses a single 600nm light source, which reduces the cyclohexene conversion rate but significantly improves product selectivity.
[0083] Example 17:
[0084] Cyclohexene (3 mmol), acetonitrile (5 mL), and the catalyst La2Co isolated from the product of Example 3 were added to a 10 mL photoreaction tube. 1.4 Cu 0.6 O6 was intermittently introduced, and the reaction mixture was reacted at 60-80℃ under 420nm cutoff light for 12 hours. After the reaction was completed, the catalyst was separated and reused up to 5 times using the same method. GC analysis showed that the cyclohexene conversion rate was 87.1% and the selectivity was 69.4%.
[0085] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.
[0086] Any aspects of this invention not described in detail are well-known to those skilled in the art.
Claims
1. A process for the high selective oxidation of cyclohexene to cyclohexenone using a rare earth based perovskite, characterized in that: The method comprises adding cyclohexene, a rare earth-based perovskite catalyst and a liquid phase reaction medium into a photo-reaction tube, heating the obtained mixture to 60-80 DEG C and keeping the temperature, intermittently feeding oxygen as an oxidant, and reacting sufficiently under light and stirring to obtain a product; the rare earth-based perovskite catalyst is selected from La2CoCuO6, La2Co 1.2 Cu 0.8 O6, La2Co 1.4 Cu 0.6 O6, La2Co 1.6 Cu 0.4 O6, La2Co 1.8 Cu 0.2 O6, LaCoO3, LaCuO3, La2CoNiO6, LaNiO3; the molar ratio of cyclohexene to the catalyst added into the photo-reaction tube is 1:(0.01-0.05); the light uses a xenon lamp as a light source, and the light is 420 nm cut-off light.
2. A process for the high selective oxidation of cyclohexene to cyclohexenone using a rare earth based perovskite catalyst as claimed in claim 1, wherein: The reaction time is 12 hours.
3. A process for the high selective oxidation of cyclohexene to cyclohexenone using a rare earth based perovskite catalyst as claimed in claim 1, wherein: The liquid reaction medium is acetonitrile; the ratio of cyclohexene to acetonitrile added in the photo reaction tube is 1 mol:(1-3 L).
4. The process for the high selective oxidation of cyclohexene to cyclohexenone using a rare earth based perovskite catalyst as claimed in claim 1, wherein: The method of intermittent oxygen feeding is to feed oxygen for several seconds every certain time interval, and the oxygen flow is controlled at 10-16 ml / min.
5. A process for the high selective oxidation of cyclohexene to cyclohexenone using a rare earth based perovskite catalyst as claimed in claim 4, wherein: Oxygen is fed for 60 seconds every 30 minutes.
6. A process for the high selective oxidation of cyclohexene to cyclohexenone using a rare earth based perovskite according to any one of claims 1 to 5, characterized in that: The product is filtered or centrifuged, the liquid part is separated to obtain cyclohexenone by evaporation or crystallization, the conversion rate reaches 89.4%, and the selectivity to cyclohexenone reaches 72.2%.
7. A process for the high selective oxidation of cyclohexene to cyclohexenone using a rare earth based perovskite according to any one of claims 1 to 5, characterized in that: The catalyst in the solid part of the product is recycled for 5 times of the reaction, and the catalytic activity and selectivity do not decrease obviously.