阅读说明：本技术 一种环己酮肟的制备方法 (Preparation method of cyclohexanone oxime ) 是由 武亚梅 魏小波 于 2021-11-08 设计创作，主要内容包括：本发明公开了一种环己酮肟的制备方法,属于石油化工技术领域。环己酮肟的制备方法包括：在肟化催化剂的存在下,将环己酮、氨和过氧化氢在溶剂中进行氨肟化反应,其中,溶剂为惰性有机溶剂。本发明提供的环己酮肟的制备方法,氨肟化反应体系中惰性有机溶剂的加入能够提高反应体系传质、溶解及非均相的分离效果,从而得到较高的环己酮肟的反应收率以及后续的悬液分离效率。同时,环己酮肟的制备方法对应的反应体系为非均相体系,无需后续分离提纯,氨肟化反应后得到含有水、油相和肟化催化剂的产物可以直接进行油水分离,将分离出的肟化催化剂返回继续用于氨肟化反应,含有环己酮肟的油相处理得到环己酮肟。(The invention discloses a preparation method of cyclohexanone oxime, belonging to the technical field of petrochemical industry. The preparation method of the cyclohexanone oxime comprises the following steps: ammoximation reaction is carried out on cyclohexanone, ammonia and hydrogen peroxide in a solvent in the presence of an oximation catalyst, wherein the solvent is an inert organic solvent. According to the preparation method of cyclohexanone oxime provided by the invention, the inert organic solvent is added into the ammoximation reaction system, so that the mass transfer, dissolution and heterogeneous separation effects of the reaction system can be improved, and the higher reaction yield of cyclohexanone oxime and the subsequent suspension separation efficiency can be obtained. Meanwhile, a reaction system corresponding to the preparation method of the cyclohexanone oxime is a heterogeneous system, subsequent separation and purification are not needed, a product containing water, an oil phase and an oximation catalyst obtained after an ammoximation reaction can be directly subjected to oil-water separation, the separated oximation catalyst is returned to be continuously used for the ammoximation reaction, and the oil phase containing the cyclohexanone oxime is treated to obtain the cyclohexanone oxime.)

1. A method for preparing cyclohexanone oxime, which is characterized by comprising the following steps: ammoximation reaction of cyclohexanone, ammonia and hydrogen peroxide in a solvent in the presence of an oximation catalyst, wherein the solvent is an inert organic solvent.

2. The method for producing cyclohexanone oxime according to claim 1, wherein the inert organic solvent is an inert organic solvent having a boiling point of more than 110 ℃; preferably, the inert organic solvent comprises at least one of alkanes of C7-C11, cycloalkanes of C8-C10, and aromatics of C7-C10; more preferably, the C7-C12 alkane comprises at least one of n-octane, isooctane, nonane, decane and isomers thereof; more preferably, the C8-C10 cycloalkane comprises at least one of l, 2-dimethylcyclohexane and n-octane; more preferably, the weight ratio of the inert organic solvent to the cyclohexanone is from 50 to 200: 100.

3. the process for producing cyclohexanone oxime as claimed in claim 1, wherein the temperature of the ammoximation reaction is 60 to 120 ℃, preferably 65 to 100 ℃.

4. The process for producing cyclohexanone oxime according to claim 1, wherein the pressure of the ammoximation reaction is 0.1-0.6MPa, and the time is 0.1-80 min; preferably, the pressure of the ammoximation reaction is 0.1-0.5MPa, and the time is 0.5-70 min.

5. The method for preparing cyclohexanone oxime as claimed in claim 1, wherein the hydrogen peroxide is added in the form of hydrogen peroxide, and the concentration of hydrogen peroxide is 27.5%, 30%, 50%, 60%, 70%.

6. The process for producing cyclohexanone oxime according to claim 1, wherein the hydrogen peroxide is used in an amount of 1 to 1.5mol, preferably 1 to 1.25 mol, relative to 1mol of the cyclohexanone; the ammonia is used in an amount of 1 to 2.0mol, preferably 1 to 1.8 mol.

7. The method for producing cyclohexanone oxime as claimed in claim 1, wherein the oximation catalyst is a titanium silicalite catalyst; preferably, the oximation catalyst is at least one selected from TS-1, TS-2 and Ti-B; preferably, the usage of the oximation catalyst accounts for 1 to 10 percent of the total usage of the reaction system by weight percent, and preferably 1.5 to 7.5 percent of the total usage of the reaction system by weight percent.

8. The process for producing cyclohexanone oxime as claimed in claim 1, wherein the ammoximation reaction system is a heterogeneous system; preferably, the ammoximation reaction is carried out under the conditions of stirring and heat extraction; more preferably, the ammoximation reaction is fed by adopting a forced external circulation or internal heat-taking continuous feeding mode.

9. The method for producing cyclohexanone oxime according to claim 8, further comprising: separating the heterogeneous system; preferably, the separation of the heterogeneous system comprises: separating the product of the ammoximation reaction into an oil phase containing cyclohexanone oxime and a water phase containing an oximation catalyst and water; preferably, after the water phase containing the oximation catalyst and water is subjected to solid-liquid separation, the oximation catalyst and the water are separated, the oximation catalyst is recycled for ammoximation reaction, and the water is discharged into a waste water system; preferably, the oil phase containing cyclohexanone oxime is processed to obtain cyclohexanone oxime.

10. The method for producing cyclohexanone oxime according to claim 1, wherein the method for producing cyclohexanone oxime comprises the steps of: dissolving cyclohexanone in an inert organic solvent, adding an oximation catalyst into the inert organic solvent, sending ammonia, hydrogen peroxide and an inert organic solvent solution containing the oximation catalyst and the cyclohexanone into an ammoximation reactor for ammoximation reaction, sending a reaction product into a first oil-water separator which is kept at 65-90 ℃ for separation to obtain an oil phase and a water phase, sending the oil phase at 65-90 ℃ into a second oil-water separator for separation, obtaining the oil phase containing cyclohexanone oxime and the water phase containing the oximation catalyst and water through two times of separation, returning the oximation catalyst separated from the water phase back to the ammoximation reactor for ammoximation reaction, sending the oil phase kept at 65-90 ℃ out, and treating to obtain the cyclohexanone oxime.

Technical Field

The invention relates to the technical field of petrochemical industry, and particularly relates to a preparation method of cyclohexanone oxime.

Background

Cyclohexanone oxime is a white columnar crystal, is an isomer with caprolactam, is an important intermediate for producing caprolactam, and 90 percent of caprolactam all over the world is obtained by rearrangement. The molecular formula of the cyclohexanone oxime is C₆H₁₁NO, relative molar mass 113.16, melting point 89-90 deg.C, boiling point 206-210 deg.C. Dissolving in water, ether, ethanol, methanol, etc.

Among the current commercial processes, there are few manufacturers of HSO, NO and HPO processes, and most manufacturers prefer the ammoximation process. The ammoximation method has the advantages of mild reaction conditions, high yield, short production process flow and low energy consumption, and becomes the optimal method for producing cyclohexanone oxime at present.

The preparation of cyclohexanone oxime by an ammoximation method mainly comprises the following steps: the method takes tertiary butanol as a solvent, gas ammonia, cyclohexanone and hydrogen peroxide as main raw materials, and cyclohexanone ammoximation reaction is carried out at 82-90 ℃ and 0.3-0.4Mpa in the presence of a TS-1 catalyst to generate cyclohexanone oxime, and the method has the advantages of high reaction yield and good separation effect; the method has the disadvantages of long flow path, consumption of a large amount of steam during the separation of the tertiary butanol, more than half of the steam consumption of the whole reaction device, high equipment input amount and high production cost; an extracting agent is added in the post-treatment process, and a large amount of steam is consumed in the extracting agent separation process. The tertiary butanol is used as a solvent in the production process and is recovered in the subsequent process, and the steam consumption of the process accounts for about 58 percent of the steam consumption of the whole oximation device in full-load production. Wherein, the tertiary butanol center is processed into cyclohexanone ammoximation device steam for large households; in addition, extraction and purification of oximes also require the consumption of large amounts of materials and energy.

In view of this, the invention is particularly proposed.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide a preparation method of cyclohexanone oxime.

The invention is realized by the following steps:

the invention provides a preparation method of cyclohexanone oxime, which comprises the following steps: ammoximation reaction is carried out on cyclohexanone, ammonia and hydrogen peroxide in a solvent in the presence of an oximation catalyst, wherein the solvent is an inert organic solvent.

The invention has the following beneficial effects:

the invention provides a preparation method of cyclohexanone oxime, which comprises the following steps: ammoximation reaction is carried out on cyclohexanone, ammonia and hydrogen peroxide in a solvent in the presence of an oximation catalyst, wherein the solvent is an inert organic solvent. In the ammoximation reaction process, in the presence of an oximation catalyst, ammonia and hydrogen peroxide can quickly react in a polar solution to generate hydroxylamine under the action of the catalyst. The generated hydroxylamine and cyclohexanone are subjected to oximation reaction without a catalyst, and the inert organic solvent is used for quickly transferring the generated cyclohexanone oxime into an organic phase, so that high cyclohexanone conversion rate and good cyclohexanone oxime selectivity can be obtained.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.

The invention aims to overcome the defects that the prior ammoximation reaction is adopted to prepare cyclohexanone oxime, the flow is long, the energy consumption is huge when tert-butyl alcohol is separated, and the equipment investment and the production cost are high; the energy consumption in the post-treatment process is large, and a novel preparation method of cyclohexanone oxime is provided.

The invention provides a preparation method of cyclohexanone oxime, which comprises the step of carrying out an ammoximation reaction on cyclohexanone, ammonia and hydrogen peroxide in a solvent in the presence of an oximation catalyst, wherein the solvent is an inert organic solvent.

The inventor of the invention aims at the defects of the current ammoximation method, and through deep research on the reaction mechanism and repeated exploration test, the inventor finds that in the presence of an oximation catalyst, ammonia and hydrogen peroxide can react rapidly to generate hydroxylamine in a polar solution under the action of the catalyst, and simultaneously react to release a large amount of heat. The generated hydroxylamine and cyclohexanone are subjected to oximation reaction without a catalyst, and the inert organic solvent is used for quickly transferring the generated cyclohexanone oxime into an organic phase, so that high cyclohexanone conversion rate and good cyclohexanone oxime selectivity can be obtained.

Based on the above mechanism, the inventors strive to find a solvent more suitable for cyclohexanone ammoximation reaction, and research again on cyclohexanone ammoximation reaction using tert-butyl alcohol as a solvent, and find that in the current ammoximation reaction process, the generated cyclohexanone oxime is usually adsorbed on a catalyst molecular sieve, and under the action of the solvent, the generated oxime is caused to be desorbed and diffused from the inside and outside of a catalyst pore channel to a reaction main fluid as soon as possible, so that the catalyst is prevented from being deactivated by deposition inside and outside the catalyst pore channel, and the solvent acts to transfer the cyclohexanone oxime generated by the reaction in time and promote the continuous reaction, that is, the obtained product cyclohexanone oxime enters the reaction main fluid through the adsorption-desorption process in the whole reaction, so as to obtain a reaction clear solution finally.

If cyclohexanone oxime directly enters a solvent without being adsorbed, the reaction speed and yield are greatly improved. Through a plurality of experiments, the inventor intends to use an inert organic solvent with the boiling point of more than 110 ℃ as a solvent for the ammoximation reaction, and the high-boiling-point organic solvent can be used at higher temperature, so that the selectable temperature range of the ammoximation reaction is improved, the product generated by the reaction can be directly dissolved in the solvent through extraction in a solvent extraction process and desorption from a molecular sieve, namely, the product of the reaction can be directly dissolved in the solvent without basically performing an adsorption-desorption process on the molecular sieve, more importantly, the solubility of the cyclohexanone oxime in the solvent at high temperature is increased, and the mass transfer, dissolution and heterogeneous separation effects of the reaction system can be improved by adding the inert organic solvent in the ammoximation reaction system, so that higher reaction yield and subsequent suspension separation efficiency are obtained. And the cyclohexanone-oxime dissolved in the solvent becomes an oil phase, and is naturally separated from a water phase formed by water and the catalyst, and the oil phase containing the cyclohexanone-oxime and the water phase containing the water and the catalyst can be obtained only by simple oil-water separation.

In addition, the preparation method of cyclohexanone oxime provided by the invention has the corresponding reaction system being a heterogeneous system, and does not need subsequent separation and purification, the product containing water, oil phase and oximation catalyst (usually solid particles) obtained after the ammoximation reaction can be directly separated in an oil-water separator and/or a decanter, the upper layer is separated to obtain the oil phase containing cyclohexanone oxime, and the lower layer is obtained to obtain the suspension containing oximation catalyst and water. The oximation catalyst and water suspension obtained from the lower layer can be separated from each other after solid-liquid separation, the oximation catalyst is recycled for ammoximation reaction, and the water enters a wastewater system. And processing the oil phase containing cyclohexanone oxime to obtain cyclohexanone oxime.

According to the preferred embodiment of the present invention, when the temperature of the ammoximation reaction is 60-100 ℃, higher cyclohexanone conversion rate and cyclohexanone oxime selectivity can be obtained. The reason is considered by the analysis of the experimental results of the inventor, and may be due to: when the temperature of the ammoximation reaction is controlled at 60-100 ℃, the solubility of the cyclohexanone-oxime in the inert solvent is increased rapidly, and the concentration of the cyclohexanone-oxime can reach more than 40 percent (weight), so that the cyclohexanone-oxime can be separated from a pore channel of the oximation catalyst rapidly and enters the inert solvent, the chemical balance of the reaction is broken, the reaction is carried out rapidly towards the direction of generating the cyclohexanone-oxime, and the reaction speed is improved.

In order to achieve the purpose, the invention adopts a technical scheme.

The preparation method of cyclohexanone oxime provided by the invention comprises the step of carrying out an ammoximation reaction on cyclohexanone, ammonia and hydrogen peroxide in a solvent in the presence of an oximation catalyst (TS-1 or a modified product thereof), wherein the solvent is an inert organic solvent.

According to the preparation method of cyclohexanone oxime provided by the invention, the addition of the inert organic solvent in the ammoximation reaction system can improve the mass transfer, dissolution and heterogeneous separation effects of the reaction system, thereby obtaining higher reaction yield and subsequent suspension separation efficiency. The amount of the inert organic solvent used in the present invention is not particularly limited, but in order to obtain higher cyclohexanone conversion and cyclohexanone oxime selectivity, it is preferable that the inert organic solvent accounts for 100% to 200% of the fed cyclohexanone.

The kind of inert organic solvent for the present invention is defined as at least one of alkanes having a boiling point of more than 110 ℃, for example, C7-C11, cycloalkanes having a boiling point of C8-C10, and aromatic hydrocarbons having a boiling point of C7-C10. Specifically, examples of the alkane of C7 to C12 include, but are not limited to, at least one of heptane, n-octane, isooctane, nonane, decane, isomers thereof, and the like. Examples of C8-C10 cycloalkanes include, but are not limited to: l, 2-dimethylcyclohexane, cyclooctane, and the like.

The restriction of the solvent dosage in the ammoximation reaction process of the invention is that the weight ratio of the inert organic solvent to the cyclohexanone is (100-: 100, so that the ammoximation reaction system has a very good mass transfer effect, thereby further improving the conversion rate of cyclohexanone and the selectivity of cyclohexanone oxime. It is usually added in a reasonable amount according to the actual amount of cyclohexanone as the reaction raw material.

According to the preparation method of cyclohexanone oxime provided by the invention, the temperature of the ammoximation reaction is preferably 60-120 ℃, more preferably 65-100 ℃, and when the temperature of the ammoximation reaction is controlled within the preferable range, the reaction is more favorably carried out, so that the conversion rate of cyclohexanone and the selectivity of cyclohexanone oxime can be more remarkably improved. Further, the pressure of the ammoximation reaction may be 0.1 to 0.6MPa, preferably 0.1 to 0.5 MPa. In the present invention, the pressure means absolute pressure. The prolonged reaction time of the ammoximation is advantageous for the improvement of the conversion rate of the reactant and the yield of the reaction product, but the excessive reaction time is not significant for the improvement of the conversion rate of the reactant and the yield of the reaction product, and therefore, the time of the ammoximation is preferably 0.1 to 80 minutes in consideration of all aspects.

The hydrogen peroxide is added in the form of hydrogen peroxide, so that the operation is more convenient, and the accurate setting and adjustment of the ratio among all the substances are more facilitated. The invention has no special limitation on the concentration of hydrogen peroxide, can be reasonably selected according to actual conditions, has high concentration, is favorable for quick reaction and improves the production capacity. For example, hydrogen peroxide may be used in a commercially available concentration of 27.5 wt%, 50 wt%, or 70 wt%.

The amount of each reaction raw material used in the ammoximation reaction process is not particularly limited in the present invention, and may be selected conventionally in the art. For example, the amount of hydrogen peroxide used may be 1 to 1.5mol, preferably 1 to 1.25 mol, relative to 1mol of cyclohexanone; the amount of ammonia used is from 1 to 2.0mol, preferably from 1 to 1.8 mol.

The type of oximation catalyst may be conventionally selected in the art, and for example, it may be a titanium silicalite catalyst, preferably at least one of a titanium silicalite having an MFI structure (e.g., TS-1), a titanium silicalite having an MEL structure (TS-2), and a titanium silicalite having a BETA structure (Ti-B). Further, the oximation catalyst may be used in an amount of 1 to 10% by weight, preferably 1.5 to 7.5% by weight, based on the whole reaction system.

The specific form of the titanium silicalite catalyst of the present invention can be selected according to the specific reaction form, for example, in a slurry bed reactor, the particle size range of the catalyst is required to be: 1-200 microns, can be an unformed titanium silicalite molecular sieve or a modified titanium silicalite molecular sieve, and can also be a formed titanium silicalite molecular sieve or a modified titanium silicalite molecular sieve catalyst.

The titanium silicalite catalyst can be obtained commercially, or can be prepared according to various methods known to those skilled in the art, and further modified. And will not be described in detail herein.

The ammoximation reaction system provided by the invention is a heterogeneous system, so that the ammoximation reaction is preferably carried out under the condition of stirring in order to ensure that the reaction raw materials and the oximation catalyst can be in sufficient contact mass transfer. The degree of stirring is determined to achieve uniform mixing of the whole reaction system and sufficient mass transfer of reactants, and those skilled in the art can know that the degree of stirring will not be described herein. In addition, in order to achieve sufficient contact mass transfer reaction of cyclohexanone, hydrogen peroxide, ammonia, and the like as reaction raw materials, the ammoximation reaction is preferably fed by a forced external circulation continuous feeding method. Wherein, the circulating amount is subject to the realization of sufficient contact mass transfer and the proper discharge amount.

In addition, the preparation method of cyclohexanone oxime provided by the invention also comprises the steps of separating the product of the ammoximation reaction into an oil phase containing cyclohexanone oxime and a water phase containing an oximation catalyst and water, then separating the oximation catalyst from the water phase, and recycling the oximation catalyst for the ammoximation reaction. Wherein the separation of the product of the ammoximation reaction into an oil phase comprising cyclohexanone oxime and an aqueous phase comprising oximation catalyst and water may be performed, for example, in a decanter and/or a decanter. The product of the ammoximation reaction is directly dissolved in an organic solvent as a lighter oil phase, while the oximation catalyst and water are insoluble in the organic solvent as a heavier water phase, thereby obtaining an oil phase containing cyclohexanone oxime and a water phase containing the oximation catalyst and water. The organic solvent may be at least one of 1, 2-dimethylcyclohexane, n-octane, nonane, and the like. The method for separating the oximation catalyst from the aqueous phase may be usually a solid-liquid separation, and specifically may be carried out in a decanter, a membrane filter or the like. In addition, in order to further reduce the water content in the oil phase, the preparation method of cyclohexanone oxime provided by the invention further comprises the step of adding an oil-water separator to the oil phase so as to further separate residual water.

According to a specific embodiment of the invention, the preparation method of cyclohexanone oxime comprises the steps of firstly dissolving cyclohexanone in an inert organic solvent, then adding an oximation catalyst into the inert organic solvent, then sending ammonia, hydrogen peroxide and an inert organic solvent solution containing oximation catalyst cyclohexanone into an ammoximation reactor to carry out ammoximation reaction at 65-90 ℃, sending a reaction product into an oil-water separator with the temperature kept at 80 ℃ for separation, then sending an oil phase with the temperature of 65-90 ℃ into a more precise separation and heat preservation oil-water separator for separation, obtaining an oil phase containing cyclohexanone oxime and a water phase containing oximation catalyst and water, and returning the water phase containing oximation catalyst and water to the ammoximation reactor again after partial dehydration for ammoximation reaction. Sending out the oil phase which is kept at 65-90 ℃ for processing to obtain the cyclohexanone oxime.

The inert organic solvent with high boiling point can not form azeotrope with water, so when the inert organic solvent with high boiling point is used, the reaction can be carried out below the boiling point, namely, the temperature is lower than 125 ℃, thereby solving the problems that the existing solvent has low reaction speed, prolonged reaction time and reduced processing capacity because the boiling point is reduced by the azeotrope and the reaction temperature can not be increased any more.

Such as: as the temperature increases, the solubility of cyclohexanone oxime in n-octane increases. The solubility of cyclohexanone oxime dissolved by n-octane reaches 3g/100g at the temperature of 25 ℃. When the temperature is 60 ℃, the solubility of the cyclohexanone oxime reaches 40g/100 g. When the temperature is 80 ℃, the solubility of cyclohexanone oxime dissolved by n-octane reaches 90g/100 g. The solubility of cyclohexanone oxime dissolved by n-octane reaches 103g/100g at 90 ℃. The outstanding advantage is that n-octane and the like have high solubility to cyclohexanone oxime at high temperature. Thus, the product of the ammoximation reaction can be quickly transferred to n-octane, and the reaction temperature of the next rearrangement reaction is above 70 ℃, so that the rearrangement reaction can be directly carried out. Meanwhile, the high-concentration cyclohexanone-oxime solution is subjected to rearrangement reaction, so that the productivity can be improved, and the economic benefit can be increased.

The traditional ammoximation reaction is carried out in a system with tert-butyl alcohol as a solvent, the conversion rate of cyclohexanone and the selectivity of cyclohexanone oxime are both high, the invention aims to improve the technical route of the prior art, reduce the energy consumption of the technical process and provide economic benefits under the condition of equivalent conversion rate of cyclohexanone and selectivity of cyclohexanone oxime rather than adopting the invention to ensure that the conversion rate and the selectivity of cyclohexanone oxime are superior to those of the prior art.

The features and properties of the present invention are described in further detail below with reference to examples.

In the following examples of the present invention, the raw material sources, components, preparation and experimental methods were the same as those of the comparative examples.

In the following examples and comparative examples:

the oximation catalyst was a titanium silicalite molecular sieve (TS-1 catalyst, purchased from chemical industry institute of Zhengzhou university, titanium oxide content of 2.7 wt.)

The conversion rate of cyclohexanone and the selectivity of cyclohexanone oxime are calculated according to the following formulas:

cyclohexanone conversion = (molar amount of cyclohexanone fed-molar amount of cyclohexanone in product)/molar amount of cyclohexanone fed oxime 100%.

Cyclohexanone oxime selectivity = the molar amount of cyclohexanone oxime in the product/(the molar amount of cyclohexanone in the feed-the molar amount of cyclohexanone in the product) X100%.

Wherein the molar amounts of cyclohexanone and cyclohexanone oxime in the light phase component are obtained by gas chromatography (Agilent 7890, DB-1701 capillary column 30m × 0.25mm × 0.25 u m).

Example 1

The weight ratio of 1, 2-dimethylcyclohexane to cyclohexanone in the mixed solution of cyclohexanone and 1, 2-dimethylcyclohexane used in this example was 140: 100. Firstly, adding 55.4g of mixed solution of cyclohexanone and 1, 2-dimethylcyclohexane, 5.0g of oximation catalyst (TS-1) and 22g of ammonia water with the concentration of 25% into a stainless steel high-pressure reaction kettle with a stirring polytetrafluoroethylene inner container, introducing nitrogen to control the pressure of the reaction kettle to be about 0.35 MPa, starting stirring, controlling the temperature of the reaction system to be 70-80 ℃, continuously feeding hydrogen peroxide (with the concentration of 27.5 weight%) into the reaction kettle at the flow rate of 0.5ml/min within 60 minutes by an advection pump, and after the materials stay in the reaction kettle for 60 minutes, obtaining a reaction product containing cyclohexanone oxime and the oximation catalyst (TS-1). And then keeping the temperature of the reaction product at 90 ℃ and standing for 10 minutes, and quickly decanting and separating an oil phase (light phase) and an aqueous phase (heavy phase) to obtain a 1, 2-dimethylcyclohexane solution containing cyclohexanone oxime as the oil phase and a solution containing an oximation catalyst (TS-1) as the aqueous phase. The light phase component is sent out for rearrangement or refining, the heavy phase component is insulated at the temperature of over 75 ℃, a small amount of 1, 2-dimethylcyclohexane is added again for extraction, and the cyclohexanone oxime is dissolved in the water phase. Then the oximation catalyst (TS-I) and most of water are recycled to the reaction kettle for ammoximation reaction, and a small amount of water is sent to a wastewater treatment center for treatment.

The analysis and calculation result shows that the conversion rate of the cyclohexanone is 99.13 percent, and the selectivity of the cyclohexanone oxime is 99.31 percent.

Example 2

In the mixed liquid of cyclohexanone and n-octane used in this example, the weight ratio of n-octane to cyclohexanone was 150: 100. Firstly, 62.5g of mixed solution of cyclohexanone and n-octane, 8.0g of oximation catalyst (TS-1) and 22g of ammonia water with the concentration of 25 percent are added into a stainless steel high-pressure reaction kettle with a stirring polytetrafluoroethylene inner container, nitrogen is introduced to control the pressure of the reaction kettle to be about 0.35 MPa, stirring is started, the temperature of the reaction system is controlled to be 80-85 ℃, then hydrogen peroxide (with the concentration of 27.5 weight percent) is continuously fed into the reaction kettle at the flow rate of 0.5ml/min within 60 minutes through an advection pump, and after the materials stay in the reaction kettle for 60 minutes, a reaction product containing cyclohexanone oxime and the oximation catalyst (TS-1) is obtained. And then keeping the temperature of the reaction product at 90 ℃ and standing for 10 minutes, and quickly decanting and separating an oil phase (light phase) and an aqueous phase (heavy phase) to obtain an n-octane solution containing cyclohexanone oxime as the oil phase and a solution containing an oximation catalyst (TS-1) as the aqueous phase. The light phase component is sent out for rearrangement or refining, the heavy phase component is insulated at the temperature of more than 70 ℃, a small amount of n-octane is added again for extraction, and the cyclohexanone oxime is dissolved in the water phase. Then the oximation catalyst (TS-I) and most of water are recycled to the reaction kettle for ammoximation reaction, and a small amount of water is sent to a wastewater treatment center for treatment.

The analysis and calculation result shows that the conversion rate of the cyclohexanone is 99.81 percent, and the selectivity of the cyclohexanone oxime is 99.62 percent.

Example 3

In the mixed liquid of cyclohexanone and n-octane used in this example, the weight ratio of n-octane to cyclohexanone was 130: 100. Firstly, adding 57.5g of mixed solution of cyclohexanone and n-octane, 5.0g of oximation catalyst (TS-1) and 22g of ammonia water with the concentration of 25% into a stainless steel high-pressure reaction kettle with a stirring polytetrafluoroethylene inner container, introducing nitrogen to control the pressure of the reaction kettle to be about 0.5MPa, starting stirring, controlling the temperature of a reaction system to be 96-100 ℃, then continuously feeding hydrogen peroxide (with the concentration of 27.5% by weight) into the reaction kettle at the flow rate of 0.8ml/min within 30 minutes by an advection pump, and standing the materials in the reaction kettle for 60 minutes to obtain a reaction product containing cyclohexanone oxime and the oximation catalyst (TS-1). And then keeping the temperature of the reaction product at 90 ℃ and standing for 10 minutes, and quickly decanting and separating an oil phase (light phase) and an aqueous phase (heavy phase) to obtain an n-octane solution containing cyclohexanone oxime as the oil phase and a solution containing an oximation catalyst (TS-1) as the aqueous phase. The light phase component is sent out for rearrangement or refining, the heavy phase component is insulated at the temperature of more than 80 ℃, a small amount of n-octane is added again for extraction, and the cyclohexanone oxime is dissolved in the water phase. Then the oximation catalyst (TS-I) and most of water are recycled to the reaction kettle for ammoximation reaction, and a small amount of water is sent to a wastewater treatment center for treatment.

The analysis and calculation result shows that the conversion rate of the cyclohexanone is 99.96 percent, and the selectivity of the cyclohexanone oxime is 99.76 percent.

Example 4

In the mixed solution of cyclohexanone and 1, 2-dimethylcyclohexane used in this example, the weight ratio of 1, 2-dimethylcyclohexane to cyclohexanone was 120: 100. Firstly, 55.5g of a mixed solution of cyclohexanone and 1, 2-dimethylcyclohexane and 4.0g of an oximation catalyst (TS-1) are added into a stainless steel high-pressure reaction kettle with a stirred polytetrafluoroethylene inner container, and then ammonia and hydrogen peroxide (the concentration is 27.5 weight percent) are continuously fed into the reaction kettle by an advection pump within 60 minutes, wherein the flow rates of the two materials are 0.6ml/min and 0.6ml/min in sequence. Controlling the temperature of the reaction system at 91-95 ℃ and the pressure at 0.4MPa, and after the materials stay in the reaction kettle for 30 minutes, obtaining a reaction product containing cyclohexanone oxime and an oximation catalyst (TS-1). And then keeping the temperature of the reaction product at 90 ℃ and standing for 10 minutes, and quickly decanting and separating an oil phase (light phase) and an aqueous phase (heavy phase) to obtain a 1, 2-dimethylcyclohexane solution containing cyclohexanone oxime as the oil phase and a solution containing an oximation catalyst (TS-1) as the aqueous phase. The light phase component is sent out for rearrangement or refining, the heavy phase component is insulated at the temperature of more than 85 ℃, a small amount of 1, 2-dimethylcyclohexane is added again for extraction, and the cyclohexanone oxime is dissolved in the water phase. Then the oximation catalyst (TS-I) and most of water are recycled to the reaction kettle for ammoximation reaction, and a small amount of water is sent to a wastewater treatment center for treatment.

The analysis and calculation result shows that the conversion rate of the cyclohexanone is 98.23 percent, and the selectivity of the cyclohexanone oxime is 98.74 percent.

Example 5

In the mixed solution of cyclohexanone and 1, 2-dimethylcyclohexane used in this example, the weight ratio of 1, 2-dimethylcyclohexane to cyclohexanone was 120: 100. Firstly, 55.5g of a mixed solution of cyclohexanone and 1, 2-dimethylcyclohexane and 5.0g of an oximation catalyst (TS-1) are added into a stainless steel high-pressure reaction kettle with a stirred polytetrafluoroethylene inner container, and then ammonia and hydrogen peroxide (the concentration is 27.5 weight percent) are continuously fed into the reaction kettle through an advection pump within 60 minutes, wherein the flow rates of the two materials are 0.6ml/min and 0.6ml/min in sequence. Controlling the temperature of the reaction system at 91-95 ℃ and the pressure at 0.4MPa, and after the materials stay in the reaction kettle for 30 minutes, obtaining a reaction product containing cyclohexanone oxime and an oximation catalyst (TS-1). And then keeping the temperature of the reaction product at 90 ℃ and standing for 10 minutes, and quickly decanting and separating an oil phase (light phase) and an aqueous phase (heavy phase) to obtain a 1, 2-dimethylcyclohexane solution containing cyclohexanone oxime as the oil phase and a solution containing an oximation catalyst (TS-1) as the aqueous phase. The light phase component is sent out for rearrangement or refining, the heavy phase component is insulated at the temperature of more than 70 ℃, a small amount of 1, 2-dimethylcyclohexane is added again for extraction, and the cyclohexanone oxime is dissolved in the water phase. Then the oximation catalyst (TS-I) and most of water are recycled to the reaction kettle for ammoximation reaction, and a small amount of water is sent to a wastewater treatment center for treatment.

The analysis and calculation result shows that the conversion rate of the cyclohexanone is 98.23 percent, and the selectivity of the cyclohexanone oxime is 98.74 percent.

Example 6

In this example, a mixed solution of cyclohexanone and n-octane is used, wherein the weight ratio of n-octane to cyclohexanone is 180: 100. The operation was the same as that of example 4, the temperature of the reaction system was controlled at 70-75 deg.C, the pressure was controlled at 0.3 MPa, and the reaction product containing cyclohexanone oxime and the oximation catalyst (TS-1) was obtained after the material stayed in the reaction vessel for 30 minutes. Treated by the same treatment method. The analysis and calculation result shows that the conversion rate of the cyclohexanone is 98.58 percent, and the selectivity of the cyclohexanone oxime is 99.34 percent. Wherein the concentration of the cyclohexanone-oxime reaches more than 39 percent,

example 7

In this example, the reaction was carried out in a tube bundle microreactor system using a weight ratio of n-octane to cyclohexanone of 160: 100. Firstly, 260g of prepared cyclohexanone and n-octane mixed solution and 12.0g of oximation catalyst (TS-1) are added into the n-octane mixed solution and stirred and mixed uniformly. Controlling the pressure of a micro-reactor system to be 0.4-0.5MPa, adding 25% ammonia water from one inlet of a micro-mixer of the micro-reactor according to the flow rate of 3.2g/min, adding 50% hydrogen peroxide from the other inlet of the micro-mixer of the micro-reactor according to the flow rate of 2.7 g/min, mixing, then entering one inlet of the micro-reactor, continuously feeding the cyclohexanone-n-octane solution containing the catalyst into the other inlet of the micro-reactor through a peristaltic pump at the flow rate of 8.5g/min for mixing reaction, controlling the temperature of the reaction system to be 91-95 ℃, and then removing a product mixture flow out of the reactor after reacting for 1.23 minutes. To obtain a reaction product containing cyclohexanone oxime and an oximation catalyst (TS-1). And then keeping the temperature of the reaction product at 90 ℃ and standing for 10 minutes, and quickly decanting and separating an oil phase (light phase) and an aqueous phase (heavy phase) to obtain an n-octane solution containing cyclohexanone oxime, wherein the concentration of the cyclohexanone oxime reaches more than 43%, and the aqueous phase is a solution containing an oximation catalyst (TS-1). The oil phase component is sent out for rearrangement or refining, the water phase component is insulated at the temperature of more than 80 ℃, a small amount of n-octane is added again for extraction, and a small amount of cyclohexanone-oxime dissolved in the water phase is extracted. Then, an oximation catalyst (TS-I) can be added into cyclohexanone and n-octane, the oximation catalyst is circulated back to the microreactor system to carry out an ammoximation reaction again, and a small amount of water is sent to a wastewater treatment center for treatment.

The analysis and calculation result shows that the conversion rate of the cyclohexanone is 99.13 percent, and the selectivity of the cyclohexanone oxime is 99.31 percent.

Example 8

The operation of this example was the same as that of the example, the reaction was carried out in a tube bundle microreactor system using a weight ratio of n-octane to cyclohexanone of 160: 100. Firstly, 260g of prepared cyclohexanone and n-octane mixed solution and 10.0g of oximation catalyst (TS-1) are added into the n-octane mixed solution and stirred and mixed uniformly. Controlling the pressure of a micro-reactor system to be 0.4-0.5MPa, adding 25% ammonia water from one inlet of a micro-mixer of the micro-reactor at the flow rate of 3.5g/min, adding 60% hydrogen peroxide from the other inlet of the micro-mixer of the micro-reactor at the flow rate of 2.1 g/min, mixing, then feeding the mixture into one inlet of the micro-reactor, continuously feeding the cyclohexanone-n-octane solution containing the catalyst into the other inlet of the micro-reactor through a peristaltic pump at the flow rate of 8.5g/min for mixing reaction, controlling the temperature of the reaction system to be 91-95 ℃, and then removing the product mixture flow out of the reactor after reacting for 1.03 minutes. To obtain a reaction product containing cyclohexanone oxime and an oximation catalyst (TS-1). And then keeping the temperature of the reaction product at 90 ℃ and standing for 10 minutes, and quickly decanting and separating an oil phase (light phase) and an aqueous phase (heavy phase) to obtain an n-octane solution containing cyclohexanone oxime, wherein the concentration of the cyclohexanone oxime reaches more than 43%, and the aqueous phase is a solution containing an oximation catalyst (TS-1). The oil phase component is sent out for rearrangement or refining, the water phase component is insulated at the temperature of more than 70 ℃, a small amount of n-octane is added again for extraction, and a small amount of cyclohexanone-oxime dissolved in the water phase is extracted. Then, an oximation catalyst (TS-I) can be added into cyclohexanone and n-octane, the oximation catalyst is circulated back to the microreactor system to carry out an ammoximation reaction again, and a small amount of water is sent to a wastewater treatment center for treatment.

The analysis and calculation result shows that the conversion rate of the cyclohexanone is 99.38 percent, and the selectivity of the cyclohexanone oxime is 99.11 percent.

Comparative example 1

Similar to the procedure of example 1, except that: the solvent is tert-butyl alcohol and deionized water; cyclohexanone: ammonia: hydrogen peroxide: tert-butyl alcohol: the water ratio is as follows: 1: 2: 1.1:15: 2. the conversion rate of cyclohexanone in the patent is 98.1%, and the selectivity of cyclohexanone oxime is 96.5%. The product after reaction needs to be distilled out of the tertiary butanol solvent to obtain cyclohexanone oxime for the next rearrangement reaction.

The advantages of inventive example 1 over this comparative example 1 are: the solvent can directly dissolve cyclohexanone oxime to enter product reaction without distillation, and can reduce the temperature of the inlet of the rearrangement reactor, reduce the intensity of subsequent reaction and better regulate and control the reaction temperature of the rearrangement reaction.

And the ratio of tert-butanol to cyclohexanone in comparative example 1 was 15; while example 1 used a solvent to cyclohexanone ratio of less than 2, the amount of solvent used in example 1 was greatly reduced.

Comparative example 2

Similar to the procedure of example 1, except that: the solvent is cyclohexane, but cyclohexane forms an azeotrope with water, so the azeotropic temperature of 69.8 ℃ is the highest reaction temperature of the heterogeneous cyclohexanone ammoximation reaction with cyclohexane as the solvent under normal pressure. The ammoximation reaction can only be carried out below the temperature, after the reaction time is 1 hour, the conversion rate of cyclohexanone is measured to be 90.6%, and the selectivity of cyclohexanone oxime is measured to be 99.1%, which indicates that the conversion rate is lower in the same reaction time by using cyclohexane as a solvent. The reaction speed can be increased by increasing the reaction temperature, and the reaction temperature cannot be increased continuously by using cyclohexane as a solvent.

In summary, the embodiment of the invention provides a preparation method of cyclohexanone oxime. The preparation method of the cyclohexanone oxime comprises the following steps: in the presence of an oximation catalyst, cyclohexanone, ammonia and hydrogen peroxide are subjected to an ammoximation reaction in a solvent, wherein the solvent is an inert organic solvent. According to the preparation method of cyclohexanone oxime provided by the invention, the inert organic solvent is added into the ammoximation reaction system, so that the mass transfer, dissolution and heterogeneous separation effects of the reaction system can be improved, and the higher reaction yield of cyclohexanone oxime and the subsequent suspension separation efficiency can be obtained. Meanwhile, a reaction system corresponding to the preparation method of the cyclohexanone oxime is a heterogeneous system, subsequent separation and purification are not needed, a product containing water, an oil phase and an oximation catalyst obtained after an ammoximation reaction can be directly subjected to oil-water separation, the separated oximation catalyst is returned to be continuously used for the ammoximation reaction, and the oil phase containing the cyclohexanone oxime is sent out for refining.

The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes will occur to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.