CN102702152B - Method for preparing organic lactone - Google Patents

Abstract

The invention provides a method for preparing organic lactone. It is characterized in that Co-MFI, a supported catalyst with a hexagonal prism shape, is used as a catalyst, and the catalyst is prepared by hydrothermal crystallization; organic ketones are used as substrates, oxygen or air is used as an oxygen source, and organic aldehydes are used as substances. Reducing agent, organic solvent was added to the reaction system. The method has the advantages of simple preparation of the catalyst; mild reaction conditions, safety, reliability, and environmental protection; the selectivity and yield of the target product obtained are close to 100%; the catalyst can be reused many times. The method solves the disadvantages of poor safety and low yield in the traditional preparation process of lactone, and has good industrial application prospects.

Description

A kind of method for preparing organic lactone

【Technical field】

The invention relates to the field of industrial catalysis in the petrochemical industry, in particular to a catalytic method for preparing organic lactones by oxidation of organic ketones.

【Background technique】

Organic lactone is an important organic synthesis intermediate, mainly used in the synthesis of polyester and copolymerization or blending modification with other esters, for example, polyε-caprolactone (PCL) is derived from ε-caprolactone (CL ) Linear aliphatic polyester obtained by ring-opening polymerization. Lactone can also be used as a strong solvent to dissolve many polymer resins, and has good solubility for some insoluble resins. For example, caprolactone can dissolve chlorinated polyolefin resins and "ESTANE" polyurethane resins.

So far, the synthesis of organic lactones has problems in raw material quality, production safety and product stability, and the synthesis technology is difficult. Currently, only a few companies in the United States, Britain, Japan and other countries are producing, and my country mainly relies on imports.

In recent years, with the continuous expansion of the application fields of organic lactones (especially ε-caprolactone), the market demand has also been increasing, and the development of lactone synthesis technology has also received more and more attention. The synthesis methods of organic lactones reported in the literature mainly include peroxyacid oxidation, low-concentration H ₂ O ₂ , O ₂ /air, etc. as oxidants to oxidize cyclohexanone to synthesize lactones, and biological oxidation. However, these methods generally do not use catalysts, and the efficiency is very low; even if some catalysts are used, the activity and selectivity of the catalysts are very low, and the catalysts are difficult to recycle.

In view of the shortcomings of the existing organic lactone synthesis process, the industry is focusing on the design and development of an efficient method and catalyst for the oxidation of organic ketones to prepare organic lactones with strong development and application prospects.

【Content of invention】

The object of the present invention is to provide a method for preparing organic lactones by catalytic oxidation of organic ketones, so as to overcome the above-mentioned defects in the prior art.

In order to achieve the purpose of the invention, the present invention proposes the following technical solutions:

A method for preparing organic lactones by catalytically oxidizing organic ketones, comprising the steps of: taking a reaction amount of catalyst, organic ketones, organic aldehydes and organic solvents and mixing them in a reactor; introducing oxygen, stirring at room temperature to After reacting at 100°C for 0.5-10 hours, the target product lactone can be obtained.

In the above method for preparing organic lactones, the catalyst used is a supported catalyst Co-MFI with a hexagonal prism shape.

In the above-mentioned organic lactone preparation method, it also includes the step of pre-preparing the supported catalyst Co-MFI of hexagonal prism shape, including:

S1. Take the template agent tetrapropylammonium hydroxide of reaction amount and be made into solution A in deionized water;

S2. Dissolve cobalt salts (such as cobalt nitrate, cobalt chloride, cobalt acetate, etc.) of the reaction amount in deionized water to form an aqueous solution containing cobalt ions;

S3. Under vigorous stirring, add the aqueous solution containing cobalt ions and the reaction amount of orthosilicate to solution A drop by drop (pH=9 or so after dropping), stir at 0°C for 1.5 hours after dropping, then raise the temperature up to room temperature;

S4. Pour the above solution into the reaction kettle, and crystallize at 170°C for 72 hours;

S5. Wash the precipitate twice with deionized water and ethanol, dry at 80°C, and roast at 550°C for 7 hours to obtain the catalyst.

In the above-mentioned organic lactone preparation method, organic ketone refers to cyclopentanone, 2-methylcyclopentanone, 3-methylcyclopentanone, cyclohexanone, 2-methylcyclohexanone, 3-methylcyclohexanone, 4-methylcyclohexanone, etc.

In the above-mentioned method for preparing organic lactones, monoaldehyde refers to acetaldehyde, butyraldehyde, benzaldehyde, o-chlorobenzaldehyde, p-chlorobenzaldehyde and the like.

In the above method for preparing organic lactones, the organic solvent refers to acetonitrile, ethyl acetate, 1,2-dichloroethane, chloroform, tetrachloromethane and the like.

In the above method for preparing organic lactones, the mass ratio of the catalyst to the organic ketone is [0.01-0.2]: 1, the molar ratio of the organic aldehyde to the organic ketone is [1-4]: 1, and the molar ratio of the oxygen to the organic ketone is [ 1-50]:1.

Preferably, in the above method for preparing the organic lactone, the temperature of the reaction system is controlled at 30-80° C. and the reaction is continued for 2-5 hours.

The method for preparing lactone by catalytic oxidation of ketone provided by the invention has a mild and easy-to-control reaction process. While obtaining high yield and selectivity, the method is safe, environmentally friendly, and the catalyst used is cheap, simple to prepare, high in stability, and can be reused many times, so it has good industrial application prospects.

【Brief description of the drawings】

Shown in Fig. 1 is the electron micrograph of the hexagonal prism morphology Co supported MFI molecular sieve catalyst adopted in the present invention;

Shown in Fig. 2 is the XRD spectrogram of the hexagonal prism shape Co supported MFI molecular sieve catalyst adopted in the present invention;

Fig. 3 shows the Fourier transform infrared spectrogram of the hexagonal prism shape Co supported MFI molecular sieve catalyst used in the present invention.

【Detailed ways】

The present invention will be further described below in conjunction with the embodiments of the present invention and comparative examples:

The structural analysis of the reaction product in the following examples of the present invention and comparative examples adopts the gas phase-mass spectrometer coupled instrument GC/MS (6890N/ 5973N). The analysis of the selectivity and yield of the target product was carried out by Agilent GC 7820A, a gas chromatograph equipped with a hydrogen flame detector and an AB-FFAP capillary column (30m×0.25mm×0.25μm).

1. Catalyst preparation

The catalyst used in the following examples of the present invention is all prepared by following method:

Get 25.8 grams of tetrapropylammonium hydroxide and 13 milliliters of deionized water to configure solution A; get 0.13 grams of cobalt nitrate hexahydrate and dissolve it in 10 milliliters of deionized water to configure cobalt nitrate solution. Under vigorous stirring, cobalt nitrate solution and 15.5 g of tetraethyl orthosilicate were added dropwise to solution A (pH=9 or so after dropping), stirred at 0°C for 1.5 hours and then warmed up to room temperature. Then it was poured into the reactor and crystallized at 170°C for 72 hours. Finally, the precipitate was washed twice with deionized water and ethanol, dried at 80°C, ground and calcined at 550°C for 7 hours to obtain the catalyst Co-MFI (n(Si)/n(Co) =100), and its electron microscope image is shown in Figure 1.

In the above steps, other cobalt salts such as cobalt chloride and cobalt acetate can be used to replace cobalt nitrate, and a Co-supported MFI molecular sieve catalyst with a hexagonal prism shape can also be prepared.

Shown in accompanying drawing 2 is the XRD spectrogram of the above-mentioned hexagonal prism shape Co loaded MFI molecular sieve catalyst that makes, can find out therefrom, the hexagonal prism type crystal that makes has good crystalline form, and crystal particle is even, it is characterized in that, Using Cu-Ka radiation, X-ray powder diffraction expressed in 2θ angle and interplanar distance (d value) is at about 7.99 (11.051), 8.89 (9.9357), 15.94 (5.5564), 23.23 (3.8257), 23.93 (3.7155) , there are characteristic peaks at 29.87 (2.9883) and 45.26 (2.0018). According to the comparative standard card JCPDS 47-0715, these diffraction peaks are typical XRD characteristic peaks of all-silicon molecular sieves, indicating that the catalyst Co-MFI synthesized by the above hydrothermal synthesis method maintains the morphology and structure of MFI and has a high crystallinity degree and orderliness.

Fig. 3 shows the Fourier transform infrared spectrum of the Co-supported MFI molecular sieve catalyst with hexagonal prism morphology prepared above. The sample shows that the centers of major vibrational bands are concentrated at 3452, 1225, 1105, 798, 557, and 458 cm ^-1 , while many smaller vibrational peaks exist between 600 and 800 cm ^-1 . Among them, 3452 cm ^-1 and 1635 cm ^-1 are mainly the absorption peaks of the stretching vibration and bending vibration of the OH bond in the water molecules existing in the molecular sieve. The absorption peaks of MFI appear at 1225, 1105, 798, 458 and 557 cm ^-1 . Among them, 1225 cm ^-1 is the antisymmetric stretching vibration absorption peak of Si-O-Si in the outer SiO4 tetrahedron. The 1105 cm ^-1 is the Si-O-Si antisymmetric stretching vibration absorption peak in the molecular sieve framework (inner SiO4 tetrahedron). The 798 cm ^-1 is the symmetric stretching vibration absorption peak of Si-O-Si in the outer SiO4 tetrahedron. The 458 cm ^-1 is the Si-O-Si bending vibration absorption peak in the zeolite framework, and the 557 cm ^-1 is the vibration absorption peak of the MFI secondary structure unit of the zeolite molecular sieve. In addition, the absorption peaks between 600 and 800 cm ^-1 mainly come from the Co-OH stretching vibration and the absorption peaks of the Co-O-Co vibration band. It shows that the Co-doped catalyst Co-MFI still maintains the typical MFI molecular sieve complex structure, indicating that the catalyst was successfully prepared.

2. Preparation of organic lactones by catalytic oxidation

Example 1

Add 0.5 g of the above-mentioned synthesized hexagonal prism-shaped Co-MFI catalyst, 10 g of cyclopentanone, 10 g of benzaldehyde, and 200 ml of carbon tetrachloride in sequence into a three-necked glass bottle, and feed oxygen at a flow rate of 100 ml /min, after reacting at 40 DEG C under stirring for 4 hours, the gas chromatography-mass spectrometry analysis result shows that the product is the target product valerolactone, and the gas chromatography analysis result shows that the selectivity and yield of valerolactone are respectively 100 % and 99%. After the catalyst was recycled 10 times, the selectivity and yield of valerolactone were still 100% and 99.2%, respectively.

Example 2

Add 0.2 g of the Co-MFI catalyst with hexagonal prism shape synthesized above, 10 g of cyclohexanone, 20 g of butyraldehyde, and 200 ml of 1,2-dichloroethane into a three-necked glass bottle in sequence, and then inject oxygen, oxygen Flow velocity is 200 milliliters/minute, after reacting at 80 ℃ under stirring for 1 hour, gas chromatography-mass spectrometry analysis result shows that product is target product caprolactone, and gas chromatography analysis result shows the selectivity and recovery of caprolactone. The rates are 100% and 99.5%, respectively.

Example 3

Add 0.8 g of the above-mentioned hexagonal prism-shaped Co-MFI catalyst, 10 g of 2-methylcyclohexanone, 40 g of p-chlorobenzaldehyde, and 200 ml of acetonitrile into a three-necked glass bottle in sequence, and then introduce oxygen at a flow rate of Be 400 milliliters/minute, after reacting at 30 ℃ under stirring for 9 hours, gas chromatography-mass spectrometry analysis result shows that product is target product 2-methyl caprolactone, and gas chromatography analysis result shows that 2-methyl caprolactone The selectivity and yield of lactone are both 100%.

Example 4

Add 1.0 g of the above-mentioned synthesized hexagonal prism-shaped Co-MFI catalyst, 10 g of 3-methylcyclohexanone, 30 g of p-chlorobenzaldehyde, and 200 ml of acetonitrile into a three-necked glass bottle in sequence, and then feed oxygen at a flow rate of Be 300 milliliters/minute, after reacting at 60 ℃ under stirring for 5 hours, gas chromatography-mass spectrometry analysis result shows that product is target product 3-methyl caprolactone, and gas chromatography analysis result shows that 3-methyl caprolactone The selectivity and yield of lactone were 100% and 99.6%, respectively.

Example 5

Add 1.5 grams of the above-mentioned synthesized hexagonal prism-shaped Co-MFI catalyst, 10 grams of 4-methylcyclohexanone, 20 grams of butyraldehyde, and 200 milliliters of chloroform into a three-necked glass bottle in turn, and feed oxygen, oxygen The flow rate is 150 ml/min. After reacting at 40° C. for 10 hours under stirring, the gas chromatography-mass spectrometry analysis results show that the product is the target product 4-methyl caprolactone, and the gas chromatography analysis results show that 4-methyl caprolactone The selectivity and yield of caprolactone were 100% and 99.8%, respectively.

Example 6

Add 1.2 grams of the above-mentioned synthesized hexagonal prism-shaped Co-MFI catalyst, 10 grams of 2-methylcyclopentanone, 20 grams of benzaldehyde, and 200 milliliters of 1,2-dichloroethane into a three-necked glass bottle in sequence. Enter oxygen, and the flow rate of oxygen is 50 milliliters/minute, after reacting at 80 ℃ under stirring for 2 hours, gas chromatography-mass spectrometry analysis result shows that product is target product 2-methylvalerolactone, and gas chromatography analysis result shows The selectivity and yield of 2-methylvalerolactone were 100% and 99.5%, respectively.

Example 7

Add 0.4 g of the above-mentioned synthesized hexagonal prism-shaped Co-MFI catalyst, 10 g of 3-methylcyclopentanone, 30 g of p-benzaldehyde, and 200 ml of carbon tetrachloride in sequence into a three-necked glass bottle, and feed in oxygen. Oxygen flow rate is 140 milliliters/minute, after reacting at 60 ℃ under stirring for 3 hours, gas chromatography-mass spectrometry analysis result shows that product is target product 3-methylvalerolactone, and gas chromatography analysis result shows that 3-methylvalerolactone The selectivity and yield of valerolactone are 100% and 100%.

Example 8

Add 0.3 g of the Co-MFI catalyst with a hexagonal prism shape synthesized above, 10 g of 4-methylcyclopentanone, 30 g of o-benzaldehyde and 200 ml of ethyl acetate into a three-necked glass bottle in sequence, and introduce oxygen, oxygen The flow rate is 250 ml/min. After reacting at 50° C. for 2 hours under stirring, the gas chromatography-mass spectrometry analysis results show that the product is the target product 4-methylvalerolactone, and the gas chromatography analysis results show that 4-methylvalerolactone The selectivity and yield of valerolactone were 100% and 99.5%, respectively. After the catalyst was recycled 10 times, the selectivity and yield of 4-methylvalerolactone were still 100% and 99.4%, respectively.

Example 9

Add 0.4 grams of the above-mentioned synthesized hexagonal prism-shaped Co-MFI catalyst, 10 grams of 2-methylcyclopentanone, 20 grams of butyraldehyde, and 200 milliliters of carbon tetrachloride into a three-necked glass bottle in sequence, and feed oxygen, oxygen The flow rate is 150 ml/min. After reacting at 60° C. for 3 hours under stirring, the gas chromatography-mass spectrometry analysis results show that the product is the target product 2-methylvalerolactone, and the gas chromatography analysis results show that 2-methylvalerolactone The selectivity and yield of valerolactone were 100% and 99.4%, respectively.

Example 10

Add 0.5 g of the above-mentioned synthesized hexagonal prism-shaped Co-MFI catalyst, 10 g of 3-methylcyclopentanone, 25 g of p-chlorobenzaldehyde, and 200 ml of acetonitrile into a three-necked glass bottle in sequence, and then feed oxygen at a flow rate of It was 300 ml/min, and after reacting at 80° C. for 2 hours under stirring, the analysis result of gas chromatography-mass spectrometry showed that the product was the target product 3-methylvalerolactone, and the analysis result of gas chromatography showed that 3-methylvalerolactone The selectivity and yield of lactone were 100% and 99.4%, respectively.

Example 11

Add 1.2 grams of the above-mentioned synthesized hexagonal prism-shaped Co-MFI catalyst, 10 grams of cyclopentanone, 15 grams of benzaldehyde, and 200 milliliters of acetonitrile into a three-necked glass bottle in sequence, and feed oxygen at a flow rate of 120 milliliters/minute. After reacting at 70°C under stirring for 2 hours, the gas chromatography-mass spectrometry analysis results showed that the product was the target product valerolactone, and the gas chromatography analysis results showed that the selectivity and yield of valerolactone were 100% and 99.6% respectively. %.

Example 12

Add 0.9 g of the above-mentioned hexagonal prism-shaped Co-MFI catalyst, 10 g of cyclopentanone, 8 g of acetaldehyde, and 200 ml of 1,2-dichloroethane into a three-neck glass bottle in sequence, and feed oxygen, oxygen Flow velocity is 80 milliliters/minute, after reacting at 50 ℃ under stirring for 4 hours, gas chromatography-mass spectrometry analysis result shows that product is target product valerolactone, and gas chromatography analysis result shows the selectivity and yield of valerolactone. The rate is 100%.

Example 13

Add 1.5 grams of the above-mentioned synthesized hexagonal prism-shaped Co-MFI catalyst, 10 grams of cyclopentanone, 25 grams of p-chlorobenzaldehyde and 200 milliliters of carbon tetrachloride in the three-necked glass bottle, and feed oxygen at a flow rate of 250 milliliters per minute, after stirring at 60 ℃ for 2 hours, gas chromatography-mass spectrometry analysis results show that the product is the target product valerolactone, and the gas chromatography analysis results show that the selectivity and yield of valerolactone are respectively 100% and 99.8%.

Example 14

Add 1.0 g of the above synthesized hexagonal prism-shaped Co-MFI catalyst, 10 g of cyclohexanone, 250 g of benzaldehyde, and 200 ml of 1,2-dichloroethane in sequence into a three-neck glass bottle, and feed oxygen, oxygen Flow velocity is 150 milliliters/minute, after reacting at 80 ℃ under stirring for 2 hours, gas chromatography-mass spectrometry analysis result shows that product is target product caprolactone, and gas chromatography analysis result shows the selectivity and recovery of caprolactone. The rates are 100% and 99.6% respectively.

Example 15

Add 0.4 grams of the above-mentioned synthesized hexagonal prism-shaped Co-MFI catalyst, 10 grams of 2-methylcyclopentanone, 15 grams of benzaldehyde, and 200 milliliters of carbon tetrachloride into a three-necked glass bottle in sequence, and feed oxygen, oxygen The flow rate is 100 ml/min, and after reacting at 30° C. for 4 hours under stirring, the gas chromatography-mass spectrometry analysis result shows that the product is the target product 2-methylvalerolactone, and the gas chromatography analysis result shows that 2-methylvalerolactone The selectivity and yield of valerolactone were 100% and 99.5%, respectively.

Example 16

Add 1.2 grams of the above-mentioned synthesized hexagonal prism-shaped Co-MFI catalyst, 10 grams of 4-cyclopentanone, 25 grams of p-chlorobenzaldehyde and 200 milliliters of ethyl acetate into a three-necked glass bottle in sequence, and feed oxygen at a flow rate of Be 200 milliliters/minute, after reacting at 60 ℃ under stirring for 2 hours, gas chromatography analysis result shows that gas chromatography-mass spectrometry analysis result shows that product is target product 4-valerolactone, the selection of 4-valerolactone The yield and yield were 100% and 99.8%, respectively.

Example 17

Add 0.8 grams of the above-mentioned synthesized hexagonal prism-shaped Co-MFI catalyst, 10 grams of cyclohexanone, 30 grams of benzaldehyde, and 200 milliliters of carbon tetrachloride into a three-necked glass bottle in sequence, and feed oxygen at a flow rate of 120 milliliters. /min, after stirring at 50°C for 3 hours, the analysis result of gas chromatography-mass spectrometry showed that the product was the target product caprolactone, and the gas chromatography analysis result showed that the selectivity and yield of caprolactone were respectively 100 % and 99.8%.

Example 18

Add 1.2 grams of the above-synthesized Co-MFI catalyst with a hexagonal prism shape, 10 grams of 2-methylcyclohexanone, 35 grams of p-chlorobenzaldehyde and 200 ml of 1,2-dichloroethane into a three-neck glass bottle in sequence , feed oxygen, the oxygen flow rate is 120 milliliters/minute, after stirring at 70 ℃ for 1 hour, gas chromatography-mass spectrometry analysis results show that the product is the target product 2-methylcaprolactone, gas chromatography analysis The results showed that the selectivity and yield of 2-methylcaprolactone were 100% and 99.0%, respectively.

Example 19

Add 0.4 g of the above-mentioned synthesized hexagonal prism-shaped Co-MFI catalyst, 10 g of 2-methylcyclohexanone, 20 g of acetaldehyde, and 200 ml of carbon tetrachloride into a three-necked glass bottle in sequence, and then feed oxygen, oxygen The flow rate is 100 ml/min, and after stirring for 3 hours at 50° C., the target product 2-methylcaprolactone is obtained. The gas chromatography analysis results show that the selectivity and yield of 2-methylcaprolactone are respectively 100% and 99.4%.

Example 20

Add 0.4 g of the above-mentioned synthesized hexagonal prism-shaped Co-MFI catalyst, 10 g of 2-methylcyclohexanone, 25 g of benzaldehyde, and 200 ml of dichlorodiethane into a three-necked glass bottle, and feed in oxygen. Oxygen flow rate is 120 milliliters/minute, after reacting at 45 ℃ under stirring for 7 hours, gas chromatography-mass spectrometry analysis result shows that the product is target product 2-methylcaprolactone, and gas chromatography analysis result shows that 2-methylcaprolactone The selectivity and yield of caprolactone were 100% and 99.6%, respectively.

3. Comparative example

In order to further illustrate the superiority of the catalyst of the present invention, the following catalysts are selected as comparative examples.

Comparative example 1

Add 0.4 grams of synthesized Fe-MFI catalyst, 10 grams of 2-methylcyclohexanone, 20 grams of acetaldehyde and 200 milliliters of 1,2-dichloroethane to a three-necked glass bottle in turn, and feed oxygen at a flow rate of 100 Milliliters per minute, after stirring at 50 ℃ for 3 hours, gas chromatography-mass spectrometry analysis results show that the product is the target product 2-methylcaprolactone, and gas chromatography analysis results show that 2-methylcaprolactone The selectivity and yield were 95% and 85%, respectively.

Comparative example 2

Add 0.4 grams of synthesized Ni-MFI catalyst, 10 grams of 2-methylcyclohexanone, 20 grams of acetaldehyde and 200 milliliters of 1,2-dichloroethane into a three-necked glass bottle in turn, and feed oxygen at a flow rate of 100 Milliliters per minute, after stirring at 50 ℃ for 3 hours, gas chromatography-mass spectrometry analysis results show that the product is the target product 2-methylcaprolactone, and gas chromatography analysis results show that 2-methylcaprolactone The selectivity and yield were 95% and 30.6%, respectively.

Comparative example 3

Add 0.4 grams of synthesized Mn-MFI catalyst, 10 grams of 2-methylcyclohexanone, 20 grams of acetaldehyde and 200 milliliters of 1,2-dichloroethane to a three-neck glass bottle in turn, and feed oxygen at a flow rate of 100 Milliliters per minute, after stirring at 50 ℃ for 3 hours, gas chromatography-mass spectrometry analysis results show that the product is the target product 2-methylcaprolactone, and gas chromatography analysis results show that 2-methylcaprolactone The selectivity and yield were 90% and 20.6%, respectively.

Comparative example 4

Add 0.4 grams of commercially available MFI catalyst, 10 grams of 2-methylcyclohexanone, 20 grams of acetaldehyde and 200 milliliters of 1,2-dichloroethane into a three-necked glass bottle in sequence, and feed oxygen at a flow rate of 100 milliliters /min, after reacting at 50 DEG C under stirring for 3 hours, the gas chromatography-mass spectrometry analysis result showed that the product was the target product 2-methylcaprolactone, and the gas chromatography analysis result showed that the content of 2-methylcaprolactone The selectivity and yield were 90% and 10.2%, respectively.

Can find out by above-mentioned embodiment and comparative example, do not adopt in the comparative example of catalyst of the present invention, the selectivity and yield of target product lactone are all lower, and adopt catalyst of the present invention, have reduced reaction condition, make reaction process Gentle and easy to control. In addition, the catalyst is cheap and easy to obtain, simple to prepare, high in stability, and can be repeatedly used to reduce costs.

The above-mentioned embodiments only express several implementation modes of the present invention, and the description thereof is relatively specific and detailed, but should not be construed as limiting the patent scope of the present invention. It should be pointed out that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent for the present invention should be based on the appended claims.

Claims (6)

1. A method for preparing organic lactones by catalytic oxidation of organic ketones, comprising the steps of: Get the catalyst of reaction amount, organic cyclic ketone, monoaldehyde and organic solvent and place in reaction vessel, mix; Introduce oxygen into the reaction system, and react at 25-100°C for 0.5-10 hours under stirring to obtain; Wherein, the catalyst is a Co-loaded MFI molecular sieve of hexagonal prism morphology; The Co-loaded MFI molecular sieve of the hexagonal prism morphology is prepared in the following manner: Get the template agent of reaction amount and deionized water and be made into solution A; Get the cobalt salt of reaction amount and be dissolved in deionized water and be made into the aqueous solution containing cobalt ion; Under vigorous stirring, the aqueous solution containing cobalt ions and the reaction amount of tetraethyl orthosilicate were added dropwise to solution A, and the temperature was raised to room temperature after stirring at 0°C for a period of time; Pour the above solution into a reaction kettle, crystallize, wash the precipitate with deionized water, dry, grind, and roast to obtain the product. the 2. the method for preparing organic lactone by organic ketone catalytic oxidation according to claim 1, is characterized in that, described organic cyclic ketone is cyclopentanone, 2-methylcyclopentanone, 3-methylcyclopentanone , cyclohexanone, 2-methylcyclohexanone, 3-methylcyclohexanone or 4-methylcyclohexanone. the 3. The method for preparing organic lactones by catalytic oxidation of organic ketones according to claim 1, characterized in that, the monoaldehyde is acetaldehyde, butyraldehyde, benzaldehyde, o-chlorobenzaldehyde or p-chlorobenzaldehyde. the 4. the method for preparing organic lactone by organic ketone catalytic oxidation according to claim 1, is characterized in that, described organic solvent is acetonitrile, ethyl acetate, 1,2-dichloroethane, trichloromethane or tetrachloromethane Chloromethane. the 5. The method for preparing organic lactones by catalytic oxidation of organic ketones according to claim 1, characterized in that the mass ratio of the catalyst to the organic ketone is [0.01-0.2]: 1, the mole of the organic aldehyde to the organic ketone The ratio is [1-4]:1, and the molar ratio of oxygen to organic ketone is [1-50]:1. the 6. The method for preparing organic lactones by catalytic oxidation of organic ketones according to claim 1, characterized in that the temperature of the reaction system is preferably controlled at 30-80°C and the reaction is continued for 2-5 hours. the