阅读说明：本技术 一种丙酮肟的制备方法 (Preparation method of acetoxime ) 是由 段仲刚 周强 徐碧涛 张军良 江煜 于 2020-12-23 设计创作，主要内容包括：本发明涉及化工领域,本发明提供了一种丙酮肟的制备方法,包括：肟化反应,汽提分离,初步纯化和蒸馏纯化等步骤；本发明制备丙酮肟有原料易得,投资周期短,经济效益明显,无三废污染,生产工艺简单,市场情况较好等优点,同时本发明采用一种钛硅改性高岭土催化剂,能大大减少反应的时间,缩短工程周期,节约能耗,降低生产成本。(The invention relates to the field of chemical industry, and provides a preparation method of acetoxime, which comprises the following steps: oximation reaction, stripping separation, primary purification, distillation purification and other steps; the method for preparing the acetone oxime has the advantages of easily available raw materials, short investment period, obvious economic benefit, no three-waste pollution, simple production process, better market condition and the like, and simultaneously, the method adopts the titanium silicon modified kaolin catalyst, so that the reaction time can be greatly shortened, the engineering period can be shortened, the energy consumption can be saved, and the production cost can be reduced.)

1. A method for preparing acetone oxime, which comprises the following steps:

step one, oximation reaction, namely adding 58-72 parts of acetone, 21-32 parts of ammonia gas, 0.05-3 parts of catalyst and 920-1800 parts of hydroxylamine sulfate solution with the mass percent concentration of 18% -24% into a mixer according to the mass parts, cooling the mixture by a cooler, then feeding the mixture into an oximation reactor, controlling the temperature to be 40-60 ℃, carrying out circulating reaction for 60-180min, overflowing reaction liquid in the oximation reactor to an oximation separator for layering, wherein the upper layer is an acetone oxime organic phase, and the lower layer is ammonium sulfate mother liquor;

step two, stripping separation, wherein the ammonium sulfate mother liquor from the oximation separator enters a stripping tower for stripping, acetone oxime and other organic matters in the ammonium sulfate mother liquor are recovered, the organic phase at the top of the tower is conveyed to an inlet of a circulating pump of the oximation reactor through a pump for recycling, and the stripping temperature is 95-120 ℃;

thirdly, primarily purifying, namely sending an acetoxime organic phase on the upper layer of the oximation separator to a crude oxime tank, pumping the acetoxime organic phase into a light component removal tower for light component removal treatment, controlling the top temperature of the light component removal tower to be 90-105 ℃ to remove light components, pumping the heavy components after pressurization by a pump to a dehydration tower for dehydration treatment, controlling the working temperature of the dehydration tower to be 100-120 ℃, obtaining an acetoxime crude product containing a small amount of impurities at the bottom of the tower, and pumping the acetoxime crude product to an acetoxime finished product tower;

and step four, distillation and purification, wherein the crude acetone oxime product is subjected to vacuum distillation in an acetone oxime product tower, the working temperature is about 85-100 ℃, low-pressure steam is continuously introduced into a reboiler of the product tower, high-purity product acetone oxime is obtained after condensation at the tower top, and the high-purity product acetone oxime is conveyed to an acetone oxime product tank through a pump.

2. The method of claim 1, wherein the acetone oxime is prepared by: the catalyst is a titanium-silicon modified kaolin catalyst, and the preparation method comprises the following steps:

weighing 8-12 parts of kaolin powder according to the mass part, dispersing the kaolin powder into 200 parts of pure water of 100-200 parts, then adding 0.5-0.9 part of ethyl orthosilicate and 0.36-0.78 part of hydrolytic agent, controlling the temperature to 45-65 ℃, stirring for reaction for 30-120min, adding 0.12-0.26 part of tetrabutyl titanate and 0.01-0.05 part of ammonium hexamolybdate after the reaction is finished, controlling the temperature to 65-85 ℃, stirring for 40-80min, then adding 0.08-0.14 part of phenylpropyl trimethoxy silane, stirring and mixing uniformly, adding the materials into a high-pressure reaction kettle, controlling the temperature to 160-200 ℃ for reaction for 1-5h, filtering, washing and drying the product, and then calcining for 0.5-5h at 650 ℃ to obtain the titanium-silicon molecular sieve;

step two, according to the mass parts, 50-70 parts of titanium silicalite molecular sieve, 1.4-3.5 parts of 7 cis-hexadecenoic acid and 300 parts of 200-propanoic acid are stirred and reacted for 3-5h at the temperature of 75-80 ℃, and then filtered and dried to obtain the 7 cis-hexadecenoic acid modified titanium silicalite molecular sieve;

adding 1.3-3.5 parts of vinyl methyl bis (butanone oxime) silane, 0.03-0.6 part of 5-9% by mass of isopropanol solution of chloroplatinic acid and 500-600 parts of toluene into a reaction kettle according to the mass parts in a nitrogen atmosphere, stirring and mixing uniformly, adding 120-280 parts of 7 cis-hexadecenoic acid modified titanium silicalite molecular sieve into the reaction kettle under stirring, stirring for 10-20h at 70-90 ℃, filtering and drying to obtain the titanium silicalite modified kaolin catalyst.

3. The method of claim 2, wherein the acetone oxime is prepared by: the kaolin powder is superfine kaolin powder, and the content of kaolin powder with the particle size of less than 2 mu m accounts for 85-95%.

4. The method of claim 2, wherein the acetone oxime is prepared by: the hydrolytic agent is tetraethyl ammonium hydroxide or tetrapropyl ammonium hydroxide or tetraethyl ammonium fluoride.

5. The method of claim 1, wherein the acetone oxime is prepared by: the cooling temperature of the cooler is 5-15 ℃.

6. The method of claim 1, wherein the acetone oxime is prepared by: the stripping tower adopts low-pressure steam for stripping.

7. The method of claim 1, wherein the acetone oxime is prepared by: and water and a small amount of acetone oxime are obtained after the tower top of the dehydrating tower is condensed and are recycled.

Technical Field

The invention relates to the field of chemical industry, in particular to a preparation method of acetoxime.

Background

Oximes are an important class of organic chemical reagents and also important starting materials for the hydrogenation of amines. The oxime synthesis method is various, generally adopts hydroxylamine and ketoxime, and is simple and practical.

CN109593046A relates to a preparation method of acetoxime. The preparation method of acetone oxime of the invention comprises the following steps: 1) dissolving acetone in an organic solvent to prepare an acetone solution, and then adding a TS-1 molecular sieve catalyst and ammonia water into the acetone solution to obtain a pre-reaction solution after mixing; 2) heating the pre-reaction liquid to 40-80 ℃, adding a hydrogen peroxide solution, reacting for 3-10h at 40-80 ℃ and under the pressure of 0-1.0MPa, filtering, rectifying, extracting with an extractant to obtain an extract liquid, and rectifying the extract liquid to obtain the acetoxime. The production process is simple, isopropanol or cyclohexane is adopted to dissolve acetone, the solubility is good, the conversion rate of acetone is improved, the isopropanol or cyclohexane is easy to separate from the generated mixture of acetone oxime at the later stage, the extraction agent is used for purifying acetone oxime, the extraction rate is high, and the whole process has no environmental pollution caused by the traditional process.

CN108069873A relates to a method for preparing acetoxime, which comprises the following steps: a) preparation of a reaction system: adding ketoxime and acetone according to the molar ratio of 1.0:5.0-35.0 in a reactor, adding an acid catalyst and a solvent, and stirring and mixing uniformly in the reactor to form a reaction system, wherein the pH value of the reaction system is 1-5; b) acetone oxime synthesis reaction: heating the reaction system obtained in the step a), controlling the reaction temperature to be 5-100 ℃, and reacting for 5-10 hours under the pressure of 0-2 atm; c) and (3) purifying acetone oxime: purifying the product obtained in step b) to obtain acetoxime. The method has the advantages of high reaction conversion rate and high selectivity of acetone oxime, and is simple in reaction process, environment-friendly, capable of reducing pollution to the environment and easy for industrial production.

CN106478450A discloses a method for purifying acetoxime, which relates to the technical field of organic compound purification. Contacting acetone, ammonia gas or ammonia water, hydrogen peroxide, a solvent and a catalyst, carrying out acetone ammoximation reaction to obtain acetone oxime reaction liquid, wherein the solvent is a mixed liquid of water and an organic solvent, filtering the acetone oxime reaction liquid in the purification process, rectifying the filtrate to remove the organic solvent, extracting the water oxime mixed liquid in a tower kettle by using an extracting agent to obtain an extract liquid, rectifying the extracting agent firstly, and then rectifying pure acetone oxime; the extractant is ethyl acetate, dichloromethane, trichloromethane or toluene. The method has the advantages of easy obtaining of the extracting agent, high extraction rate, easy separation of the extracting agent, simple process, low energy consumption, mild separation conditions, high product purity and the like.

The process and the technology for preparing the acetone oxime in the invention and the prior art have the problems of long reaction time and low yield.

Disclosure of Invention

In order to solve the above problems, the present invention provides a method for preparing acetoxime.

The method takes acetone, ammonia gas and hydroxylamine sulfate as initial raw materials, and carries out oximation reaction under the action of a catalyst to generate acetone oxime, wherein the reaction formula is as follows:

a method for preparing acetone oxime, which comprises the following steps:

step one, oximation reaction, namely adding 58-72 parts of acetone, 21-32 parts of ammonia gas, 0.05-3 parts of catalyst and 920-1800 parts of hydroxylamine sulfate solution with the mass percent concentration of 18% -24% into a mixer according to the mass parts, cooling the mixture by a cooler, then feeding the mixture into an oximation reactor, controlling the temperature to be 40-60 ℃, carrying out circulating reaction for 60-180min, overflowing reaction liquid in the oximation reactor to an oximation separator for layering, wherein the upper layer is an acetone oxime organic phase, and the lower layer is ammonium sulfate mother liquor;

step two, stripping separation, wherein the ammonium sulfate mother liquor from the oximation separator enters a stripping tower for stripping, acetone oxime and other organic matters in the ammonium sulfate mother liquor are recovered, the organic phase at the top of the tower is conveyed to an inlet of a circulating pump of the oximation reactor through a pump for recycling, and the stripping temperature is 95-120 ℃;

thirdly, primarily purifying, namely sending an acetoxime organic phase on the upper layer of the oximation separator to a crude oxime tank, pumping the acetoxime organic phase into a light component removal tower for light component removal treatment, controlling the top temperature of the light component removal tower to be 90-105 ℃ to remove light components, pumping the heavy components after pressurization by a pump to a dehydration tower for dehydration treatment, controlling the working temperature of the dehydration tower to be 100-120 ℃, obtaining an acetoxime crude product containing a small amount of impurities at the bottom of the tower, and pumping the acetoxime crude product to an acetoxime finished product tower;

and step four, distillation and purification, wherein the crude acetone oxime product is subjected to vacuum distillation in an acetone oxime product tower, the working temperature is about 85-100 ℃, low-pressure steam is continuously introduced into a reboiler of the product tower, high-purity product acetone oxime is obtained after condensation at the tower top, and the high-purity product acetone oxime is conveyed to an acetone oxime product tank through a pump.

The catalyst is a titanium-silicon modified kaolin catalyst, and the preparation method comprises the following steps:

weighing 8-12 parts of kaolin powder according to the mass part, dispersing the kaolin powder into 200 parts of pure water of 100-200 parts, then adding 0.5-0.9 part of ethyl orthosilicate and 0.36-0.78 part of hydrolytic agent, controlling the temperature to 45-65 ℃, stirring for reaction for 30-120min, adding 0.12-0.26 part of tetrabutyl titanate and 0.01-0.05 part of ammonium hexamolybdate after the reaction is finished, controlling the temperature to 65-85 ℃, stirring for 40-80min, then adding 0.08-0.14 part of phenylpropyl trimethoxy silane, stirring and mixing uniformly, adding the materials into a high-pressure reaction kettle, controlling the temperature to 160-200 ℃ for reaction for 1-5h, filtering, washing and drying the product, and then calcining for 0.5-5h at 650 ℃ to obtain the titanium-silicon molecular sieve;

and step two, according to the mass parts, controlling the temperature to be 75-80 ℃ and stirring and reacting for 3-5h by using 50-70 parts of the titanium silicalite molecular sieve, 1.4-3.5 parts of 7 cis-hexadecenoic acid and 300 parts of 200-flation acid, filtering and drying to obtain the 7 cis-hexadecenoic acid modified titanium silicalite molecular sieve.

Adding 1.3-3.5 parts of vinyl methyl bis (butanone oxime) silane, 0.03-0.6 part of 5-9% by mass of isopropanol solution of chloroplatinic acid and 500-600 parts of toluene into a reaction kettle according to the mass parts in a nitrogen atmosphere, stirring and mixing uniformly, adding 120-280 parts of 7 cis-hexadecenoic acid modified titanium silicalite molecular sieve into the reaction kettle under stirring, stirring for 10-20h at 70-90 ℃, filtering and drying to obtain the titanium silicalite modified kaolin catalyst.

The reaction mechanism is as follows:

hydroxyl on the surface of the titanium silicalite molecular sieve reacts with 7 cis-hexadecenoic acid, 7 cis-hexadecane ester group is introduced to the surface of the titanium silicalite molecular sieve, and then the titanium silicalite molecular sieve and vinyl methyl bis (butanone oxime) silane undergo hydrosilylation, and a part of reaction equations are simply shown as follows:

thus obtaining the titanium silicon modified kaolin catalyst.

The kaolin powder is superfine kaolin powder, and the content of kaolin powder with the particle size of less than 2 mu m accounts for 85-95%.

The hydrolytic agent is tetraethyl ammonium hydroxide or tetrapropyl ammonium hydroxide or tetraethyl ammonium fluoride.

The cooling temperature of the cooler is 5-15 ℃.

The stripping tower adopts low-pressure steam for stripping.

And water and a small amount of acetone oxime are obtained after the tower top of the dehydrating tower is condensed and are recycled.

The titanium-silicon modified kaolin catalyst prepared by the method is prepared by using superfine kaolin powder which is cheap and easy to obtain and has large specific surface area to load metal molybdenum after titanium-silicon modification, and the catalytic performance of the titanium-silicon modified kaolin catalyst in an oximation reaction is obviously improved.

The invention provides a preparation method of acetoxime, the method has the advantages of easily available raw materials, short investment period, obvious economic benefit, no three-waste pollution, simple production process, better market condition and the like, and simultaneously, the method adopts a titanium-silicon modified kaolin catalyst for catalytic reaction, so that the reaction time can be greatly reduced, the engineering period can be shortened, the energy consumption can be saved, and the production cost can be reduced; in addition, the invention can convert the cheap liquid hydroxylamine sulfate into the solid ammonium sulfate which has the advantages of high price, convenient storage and transportation, safer use and wider application, and has more obvious economic benefit.

Drawings

FIG. 1 is a chromatogram of the acetone oxime product prepared in example 3:

chromatography FL9510 data workstation.

FIG. 2 is a Fourier infrared spectrum of the acetone oxime product prepared in example 3.

Detailed Description

The invention is further illustrated by the following specific examples:

determining the content of acetoxime by gas chromatography; the product yield is calculated according to the feeding amount of acetone, and the calculation equation is as follows:

yield of acetoxime (%) =73.1m₁/58.1m₂×100%

In the formula m₁Is the input amount of acetone, m₂Acetone oxime yield.

Example 1

A method for preparing acetone oxime, which comprises the following steps:

adding 58kg of acetone, 21kg of ammonia gas, 0.05kg of catalyst and 920kg of hydroxylamine sulfate solution with the mass percent concentration of 18% into a mixer, cooling by a cooler, then feeding into an oximation reactor, controlling the temperature at 40 ℃, carrying out a circulating reaction for 60min, overflowing reaction liquid in the oximation reactor to an oximation separator for layering, wherein the upper layer is an acetone oxime organic phase, and the lower layer is ammonium sulfate mother liquor;

step two, stripping separation, wherein the ammonium sulfate mother liquor from the oximation separator enters a stripping tower for stripping, acetone oxime and other organic matters in the ammonium sulfate mother liquor are recovered, the organic phase at the top of the tower is conveyed to an inlet of a circulating pump of the oximation reactor for recycling through a pump, and the stripping temperature is 95 ℃;

thirdly, primarily purifying, namely, oximating an acetone oxime organic phase on the upper layer of the separator to a crude oxime tank, then pumping the acetone oxime organic phase into a light component removal tower for light component removal treatment, controlling the top temperature of the light component removal tower to be 90 ℃ to remove light components, pumping the heavy components after being pressurized by a pump to a dehydration tower for dehydration treatment, controlling the working temperature of the dehydration tower to be 100 ℃, obtaining an acetone oxime crude product containing a small amount of impurities at the bottom of the tower, and pumping the acetone oxime crude product to an acetone oxime finished product tower;

and step four, distillation and purification, wherein the acetone oxime crude product is subjected to vacuum distillation in an acetone oxime finished product tower, the working temperature is about 85 ℃, low-pressure steam is continuously introduced into a reboiler of the finished product tower, high-purity acetone oxime finished product is obtained after condensation at the tower top, and the acetone oxime finished product is conveyed to an acetone oxime finished product tank through a pump.

The catalyst is a titanium-silicon modified kaolin catalyst, and the preparation method comprises the following steps:

weighing 8kg of kaolin powder, dispersing the kaolin powder into 100kg of pure water, then adding 0.5kg of ethyl orthosilicate and 0.368kg of hydrolytic agent, controlling the temperature to 45 ℃, stirring and reacting for 30min, then adding 0.12kg of tetrabutyl titanate and 0.01kg of ammonium hexamolybdate, controlling the temperature to 65 ℃, stirring for 40min, then adding 0.08kg of phenyl propyl trimethoxy silane, stirring and mixing uniformly, then adding the materials into a high-pressure reaction kettle, controlling the temperature to react for 1h at 160 ℃, filtering, washing and drying the product, and then calcining for 0.5h at 500 ℃ to obtain the titanium-silicon molecular sieve.

50kg of titanium silicalite molecular sieve, 1.4kg of 7 cis-hexadecenoic acid and 200kg of water are stirred and reacted for 3 hours at the temperature of 75 ℃, and then the titanium silicalite molecular sieve modified by the 7 cis-hexadecenoic acid is obtained after filtration and drying.

Under the nitrogen atmosphere, 1.3kg of vinyl methyl bis (butanone oxime) silane, 0.03kg of isopropanol solution of chloroplatinic acid with the mass percent concentration of 5 percent and 500kg of toluene are added into a reaction kettle, after uniform stirring and mixing, 120kg of 7 cis-hexadecenoic acid modified titanium silicalite molecular sieve is added into the reaction kettle under stirring, stirred for 10 hours at 70 ℃, filtered and dried, and the titanium silicalite modified kaolin catalyst can be obtained.

The kaolin powder is superfine kaolin powder, and the content of kaolin powder with the particle size of less than 2 mu m accounts for 85 percent.

The hydrolytic agent is tetraethyl ammonium hydroxide.

The cooling temperature of the cooler is 5 ℃.

The stripping tower adopts low-pressure steam for stripping.

And water and a small amount of acetone oxime are obtained after the tower top of the dehydrating tower is condensed and are recycled.

Example 2

A method for preparing acetone oxime, which comprises the following steps:

adding 64kg of acetone, 27kg of ammonia gas, 1.4kg of catalyst and 1400kg of hydroxylamine sulfate solution with the mass percentage concentration of 22% into a mixer, cooling by a cooler, then feeding into an oximation reactor, controlling the temperature at 50 ℃, carrying out a cyclic reaction for 120min, overflowing reaction liquid in the oximation reactor to an oximation separator for layering, wherein the upper layer is an acetone oxime organic phase, and the lower layer is ammonium sulfate mother liquor;

step two, stripping separation, wherein the ammonium sulfate mother liquor from the oximation separator enters a stripping tower for stripping, acetone oxime and other organic matters in the ammonium sulfate mother liquor are recovered, the organic phase at the top of the tower is conveyed to an inlet of a circulating pump of the oximation reactor for recycling through a pump, and the stripping temperature is 105 ℃;

thirdly, primarily purifying, namely, oximating an acetone oxime organic phase on the upper layer of the separator to a crude oxime tank, then pumping the acetone oxime organic phase into a light component removal tower for light component removal treatment, controlling the top temperature of the light component removal tower to be 100 ℃ to remove light components, pumping the heavy components after being pressurized by a pump to a dehydration tower for dehydration treatment, controlling the working temperature of the dehydration tower to be 110 ℃, obtaining an acetone oxime crude product containing a small amount of impurities at the bottom of the tower, and pumping the acetone oxime crude product to an acetone oxime finished product tower;

and step four, distillation and purification, wherein the crude acetone oxime product is subjected to vacuum distillation in an acetone oxime product tower, the working temperature is about 95 ℃, low-pressure steam is continuously introduced into a reboiler of the product tower, high-purity product acetone oxime is obtained after condensation at the tower top, and the high-purity product acetone oxime is conveyed to an acetone oxime product tank through a pump.

The catalyst is a titanium-silicon modified kaolin catalyst, and the preparation method comprises the following steps:

weighing 10kg of kaolin powder, dispersing into 140kg of pure water, then adding 0.7kg of ethyl orthosilicate and 0.54kg of hydrolytic agent, controlling the temperature to 55 ℃, stirring and reacting for 60min, then adding 0.18kg of tetrabutyl titanate and 0.03kg of ammonium hexamolybdate, controlling the temperature to 75 ℃, stirring for 60min, then adding 0.11kg of phenyl propyl trimethoxy silane, stirring and mixing uniformly, then adding the materials into a high-pressure reaction kettle, controlling the temperature to react for 3h at 180 ℃, filtering, washing and drying the product, and then calcining for 2.5h at 550 ℃ to obtain a titanium-silicon molecular sieve;

57kg of titanium silicalite molecular sieve, 1.9kg of 7 cis-hexadecenoic acid and 260kg of water are stirred and reacted for 3.5 hours at the temperature of 77 ℃, and then the titanium silicalite molecular sieve modified by the 7 cis-hexadecenoic acid is obtained after filtration and drying.

Under the nitrogen atmosphere, 1.9kg of vinyl methyl bis (butanone oxime) silane, 0.3kg of isopropanol solution of chloroplatinic acid with the mass percent concentration of 5 percent and 500kg of toluene are added into a reaction kettle, after uniform stirring and mixing, 120kg of 7 cis-hexadecenoic acid modified titanium silicalite molecular sieve is added into the reaction kettle under stirring, stirred for 10 hours at 70 ℃, filtered and dried, and the titanium silicalite modified kaolin catalyst can be obtained.

The kaolin powder is superfine kaolin powder, and the content of the kaolin powder with the particle size of less than 2 mu m accounts for 90 percent.

The hydrolytic agent is tetrapropylammonium hydroxide.

The cooling temperature of the cooler is 10 ℃.

The stripping tower adopts low-pressure steam for stripping.

And water and a small amount of acetone oxime are obtained after the tower top of the dehydrating tower is condensed and are recycled.

Example 3

A method for preparing acetone oxime, which comprises the following steps:

adding 72kg of acetone, 32kg of ammonia gas, 3kg of catalyst and 1800kg of hydroxylamine sulfate solution with the mass percentage concentration of 24% into a mixer, cooling by a cooler, then feeding into an oximation reactor, controlling the temperature at 60 ℃, carrying out a circulating reaction for 180min, overflowing reaction liquid in the oximation reactor to an oximation separator for layering, wherein the upper layer is an acetone oxime organic phase, and the lower layer is ammonium sulfate mother liquor;

step two, stripping separation, wherein the ammonium sulfate mother liquor from the oximation separator enters a stripping tower for stripping, acetone oxime and other organic matters in the ammonium sulfate mother liquor are recovered, the organic phase at the top of the tower is conveyed to an inlet of a circulating pump of the oximation reactor through a pump for recycling, and the stripping temperature is 120 ℃;

thirdly, primarily purifying, namely, oximating an acetone oxime organic phase on the upper layer of the separator to a crude oxime tank, then pumping the acetone oxime organic phase into a light component removal tower for light component removal treatment, controlling the top temperature of the light component removal tower to be 105 ℃ to remove light components, pumping the heavy components after being pressurized by a pump to a dehydration tower for dehydration treatment, controlling the working temperature of the dehydration tower to be 120 ℃, obtaining an acetone oxime crude product containing a small amount of impurities at the bottom of the tower, and pumping the acetone oxime crude product to an acetone oxime finished product tower;

and step four, distillation and purification, wherein the crude acetone oxime product is subjected to vacuum distillation in an acetone oxime product tower, the working temperature is about 100 ℃, low-pressure steam is continuously introduced into a reboiler of the product tower, high-purity product acetone oxime is obtained after condensation at the tower top, and the high-purity product acetone oxime is conveyed to an acetone oxime product tank through a pump.

The catalyst is a titanium-silicon modified kaolin catalyst, and the preparation method comprises the following steps:

weighing 12kg of kaolin powder, dispersing into 200kg of pure water, adding 0.9kg of ethyl orthosilicate and 0.78kg of hydrolytic agent, controlling the temperature to 65 ℃, stirring for reaction for 120min, adding 0.26kg of tetrabutyl titanate and 0.05kg of ammonium hexamolybdate after the reaction is finished, controlling the temperature to 85 ℃, stirring for 80min, adding 0.14kg of phenyl propyl trimethoxy silane, stirring and mixing uniformly, adding the material into a high-pressure reaction kettle, controlling the temperature to react for 5h at 200 ℃, filtering, washing and drying the product, and calcining for 5h at 650 ℃ to obtain the titanium-silicon molecular sieve;

70kg of titanium silicalite molecular sieve, 3.5kg of 7 cis-hexadecenoic acid and 300kg of water are stirred and reacted for 5 hours at the temperature controlled by 80 ℃, and then the titanium silicalite molecular sieve modified by the 7 cis-hexadecenoic acid is obtained after filtration and drying.

Under the nitrogen atmosphere, 3.5kg of vinyl methyl bis (butanone oxime) silane, 0.6kg of isopropanol solution of chloroplatinic acid with the mass percent concentration of 9 percent and 600kg of toluene are added into a reaction kettle, after uniform stirring and mixing, 280kg of 7 cis-hexadecenoic acid modified titanium silicalite molecular sieve is added into the reaction kettle under stirring, stirred for 20 hours at 90 ℃, filtered and dried, and the titanium silicalite modified kaolin catalyst can be obtained.

The kaolin powder is superfine kaolin powder, and the content of the kaolin powder with the particle size of less than 2 mu m accounts for 95 percent.

The hydrolytic agent is tetraethyl ammonium fluoride.

The cooling temperature of the cooler is 15 ℃.

The stripping tower adopts low-pressure steam for stripping.

And water and a small amount of acetone oxime are obtained after the tower top of the dehydrating tower is condensed and are recycled.

The chromatographic analysis of the samples is shown in FIG. 1, the data of which are given in the following table

The content and yield of acetoxime obtained in the above examples are shown in the following table:

	content (%)	Yield (%)
			Example 1	99.02	92.34
Example 2	99.21	93.71
			Example 3	99.92	96.37

Comparative example 1

A method for preparing acetone oxime, which comprises the following steps:

adding 58kg of acetone, 21kg of ammonia gas, 0.05kg of catalyst and 920kg of hydroxylamine sulfate solution with the mass percent concentration of 18% into a mixer, cooling by a cooler, then feeding into an oximation reactor, controlling the temperature at 40 ℃, carrying out a circulating reaction for 60min, overflowing reaction liquid in the oximation reactor to an oximation separator for layering, wherein the upper layer is an acetone oxime organic phase, and the lower layer is ammonium sulfate mother liquor;

step two, stripping separation, wherein the ammonium sulfate mother liquor from the oximation separator enters a stripping tower for stripping, acetone oxime and other organic matters in the ammonium sulfate mother liquor are recovered, the organic phase at the top of the tower is conveyed to an inlet of a circulating pump of the oximation reactor for recycling through a pump, and the stripping temperature is 95 ℃;

thirdly, primarily purifying, namely, oximating an acetone oxime organic phase on the upper layer of the separator to a crude oxime tank, then pumping the acetone oxime organic phase into a light component removal tower for light component removal treatment, controlling the top temperature of the light component removal tower to be 90 ℃ to remove light components, pumping the heavy components after being pressurized by a pump to a dehydration tower for dehydration treatment, controlling the working temperature of the dehydration tower to be 100 ℃, obtaining an acetone oxime crude product containing a small amount of impurities at the bottom of the tower, and pumping the acetone oxime crude product to an acetone oxime finished product tower;

and step four, distillation and purification, wherein the acetone oxime crude product is subjected to vacuum distillation in an acetone oxime finished product tower, the working temperature is about 85 ℃, low-pressure steam is continuously introduced into a reboiler of the finished product tower, high-purity acetone oxime finished product is obtained after condensation at the tower top, and the acetone oxime finished product is conveyed to an acetone oxime finished product tank through a pump.

The catalyst is a kaolin catalyst.

The cooling temperature of the cooler is 5 ℃.

The stripping tower adopts low-pressure steam for stripping.

And water and a small amount of acetone oxime are obtained after the tower top of the dehydrating tower is condensed and are recycled.

Comparative example 2

A method for preparing acetone oxime, which comprises the following steps:

adding 58kg of acetone, 21kg of ammonia gas, 0.05kg of catalyst and 920kg of hydroxylamine sulfate solution with the mass percent concentration of 18% into a mixer, cooling by a cooler, then feeding into an oximation reactor, controlling the temperature at 40 ℃, carrying out a circulating reaction for 60min, overflowing reaction liquid in the oximation reactor to an oximation separator for layering, wherein the upper layer is an acetone oxime organic phase, and the lower layer is ammonium sulfate mother liquor;

step two, stripping separation, wherein the ammonium sulfate mother liquor from the oximation separator enters a stripping tower for stripping, acetone oxime and other organic matters in the ammonium sulfate mother liquor are recovered, the organic phase at the top of the tower is conveyed to an inlet of a circulating pump of the oximation reactor for recycling through a pump, and the stripping temperature is 95 ℃;

thirdly, primarily purifying, namely, oximating an acetone oxime organic phase on the upper layer of the separator to a crude oxime tank, then pumping the acetone oxime organic phase into a light component removal tower for light component removal treatment, controlling the top temperature of the light component removal tower to be 90 ℃ to remove light components, pumping the heavy components after being pressurized by a pump to a dehydration tower for dehydration treatment, controlling the working temperature of the dehydration tower to be 100 ℃, obtaining an acetone oxime crude product containing a small amount of impurities at the bottom of the tower, and pumping the acetone oxime crude product to an acetone oxime finished product tower;

and step four, distillation and purification, wherein the acetone oxime crude product is subjected to vacuum distillation in an acetone oxime finished product tower, the working temperature is about 85 ℃, low-pressure steam is continuously introduced into a reboiler of the finished product tower, high-purity acetone oxime finished product is obtained after condensation at the tower top, and the acetone oxime finished product is conveyed to an acetone oxime finished product tank through a pump.

The catalyst is a titanium-silicon modified kaolin catalyst, and the preparation method comprises the following steps:

weighing 8kg of kaolin powder, dispersing the kaolin powder into 100kg of pure water, then adding 0.5kg of ethyl orthosilicate and 0.368kg of hydrolytic agent, controlling the temperature to 45 ℃, stirring and reacting for 30min, then adding 0.12kg of tetrabutyl titanate, controlling the temperature to 65 ℃, stirring for 40min, then adding 0.08kg of phenyl propyl trimethoxy silane, stirring and mixing uniformly, then adding the materials into a high-pressure reaction kettle, controlling the temperature to react for 1h at 160 ℃, filtering, washing and drying the product, and then calcining for 0.5h at 500 ℃ to obtain the titanium-silicon modified kaolin catalyst.

The kaolin powder is superfine kaolin powder, and the content of kaolin powder with the particle size of less than 2 mu m accounts for 85 percent.

The hydrolytic agent is tetraethyl ammonium hydroxide.

The cooling temperature of the cooler is 5 ℃.

The stripping tower adopts low-pressure steam for stripping.

And water and a small amount of acetone oxime are obtained after the tower top of the dehydrating tower is condensed and are recycled.

Comparative example 3

A method for preparing acetone oxime, which comprises the following steps:

adding 58kg of acetone, 21kg of ammonia gas and 920kg of hydroxylamine sulfate solution with the mass percent concentration of 18% into a mixer, cooling by a cooler, then feeding into an oximation reactor, controlling the temperature at 40 ℃, carrying out a circulating reaction for 60min, overflowing reaction liquid in the oximation reactor to an oximation separator for layering, wherein the upper layer is an acetone oxime organic phase, and the lower layer is ammonium sulfate mother liquor;

step two, stripping separation, wherein the ammonium sulfate mother liquor from the oximation separator enters a stripping tower for stripping, acetone oxime and other organic matters in the ammonium sulfate mother liquor are recovered, the organic phase at the top of the tower is conveyed to an inlet of a circulating pump of the oximation reactor for recycling through a pump, and the stripping temperature is 95 ℃;

thirdly, primarily purifying, namely, oximating an acetone oxime organic phase on the upper layer of the separator to a crude oxime tank, then pumping the acetone oxime organic phase into a light component removal tower for light component removal treatment, controlling the top temperature of the light component removal tower to be 90 ℃ to remove light components, pumping the heavy components after being pressurized by a pump to a dehydration tower for dehydration treatment, controlling the working temperature of the dehydration tower to be 100 ℃, obtaining an acetone oxime crude product containing a small amount of impurities at the bottom of the tower, and pumping the acetone oxime crude product to an acetone oxime finished product tower;

and step four, distillation and purification, wherein the acetone oxime crude product is subjected to vacuum distillation in an acetone oxime finished product tower, the working temperature is about 85 ℃, low-pressure steam is continuously introduced into a reboiler of the finished product tower, high-purity acetone oxime finished product is obtained after condensation at the tower top, and the acetone oxime finished product is conveyed to an acetone oxime finished product tank through a pump.

The cooling temperature of the cooler is 5 ℃.

The stripping tower adopts low-pressure steam for stripping.

And water and a small amount of acetone oxime are obtained after the tower top of the dehydrating tower is condensed and are recycled.

The content and yield of acetoxime obtained in the above examples are shown in the following table:

	content (%)	Yield (%)
			Comparative example 1	97.64	76.29
Comparative example 2	98.17	81.33
			Comparative example 3	96.37	54.26