A process for the cyclododecanone oximation

Abstract

The application discloses a cyclododecanone oximation method, which adopts cyclododecanone and hydroxylamine salt to react, adopts alcohol ether phosphate as a reaction surfactant, and adopts hydroxamic acid as a metal ion chelating agent, so that the reaction rate of cyclododecanone oximation can be effectively improved, and the utilization rate of hydroxylamine can be improved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of organic synthesis, and relates to a method for oximation of cyclododecanone. BACKGROUND

[0002] Cyclododecanone oxime is a key monomer for the synthesis of nylon 12. Its synthesis methods include the Lassaigne method, the HPO method, the solid hydroxylamine salt oximation method, the co-oximation method, the oxime exchange method, the ammonio-oximation method, and the nitromethane method. The solid hydroxylamine salt oximation method is the most traditional and mature process for synthesizing cyclododecanone oxime.

[0003] Since cyclododecanone has low water solubility, the reaction between cyclododecanone and hydroxylamine is an interfacial reaction, the reaction rate is low, the production efficiency is low, and the equipment investment is large. In order to improve the oximation reaction rate, patent US20130023697 reports adding an additive to an alkane solvent to solve the mass transfer problem of oil-water two phases, thereby shortening the oximation reaction time. The additive is a carboxylic acid or a carboxylic acid salt, but the oximation reaction time is still more than 4 hours; patent CN1860098A reports using an alkyl sulfonate as a phase transfer catalyst, but the oximation reaction time is still more than 8 hours.

[0004] Since free hydroxylamine is unstable, in order to improve the utilization rate of hydroxylamine and reduce the decomposition of hydroxylamine, patent CN110498748A reports using L-arginine and its derivatives as a chelating agent for iron ions, but the content of iron ions is still more than 0.1 ppm, and the decomposition rate of hydroxylamine is more than 0.5%.

[0005] It is of great significance to create a cyclododecanone oximation method with fast oximation reaction rate and high hydroxylamine utilization rate.

[0006] The present application relates to a method for oximation of cyclododecanone, which can significantly improve the oximation reaction rate and the utilization rate of hydroxylamine. The present application uses alcohol ether phosphate as a reaction surfactant and hydroxamic acid as a metal ion chelating agent. The present method can effectively improve the reaction rate of cyclododecanone oximation and the utilization rate of hydroxylamine. By using the present method, the oximation reaction time of cyclododecanone can be reduced to within 2 hours, and the decomposition rate of hydroxylamine can be reduced to below 0.5%.

[0007] To achieve the above technical effects, the present application adopts the following technical solutions:

[0008] A method for oximation of cyclododecanone, comprising the following steps:

[0009] 1) mixing cyclododecanone, a solvent, a surfactant, and a metal ion chelating agent by stirring, replacing with nitrogen, and then back-pressing to 50-80 KPa (G) and heating to 90-100℃ by oil bath;

[0010] 2) Dissolve the hydroxylamine salt in water, neutralize with a basic solution, and then add to the mixed solution of step 1) after preheating.

[0011] 3) After the reaction is completed, stop stirring and separate the oil and water to obtain cyclododecanone oxime.

[0012] The surfactant described in the present application is an alcohol ether phosphate, preferably isomeric tridecanol ether phosphate, dodecanol ether phosphate, tetradocosanol ether phosphate, more preferably isomeric tridecanol ether phosphate or dodecanol ether phosphate, and the amount of alcohol ether phosphate is 0.01-0.5% of the mass of cyclododecanone, preferably 0.1-0.3%.

[0013] The metal ion chelating agent described in the present application is a hydroxamic acid, preferably one or more of salicylhydroxamic acid, benzylhydroxamic acid, octylhydroxamic acid, 1-hydroxy-2-naphthylhydroxamic acid, acetylhydroxamic acid, L-asparagine-B-hydroxamic acid, benzenesulfonylhydroxamic acid, and octylhydroxamic acid, preferably salicylhydroxamic acid or 1-hydroxy-2-naphthylhydroxamic acid; the amount of hydroxamic acid is 0.01-0.1% of the mass of cyclododecanone, preferably 0.02-0.05%.

[0014] The hydroxylamine salt described in the present application includes but is not limited to one or more of hydroxylamine hydrochloride, hydroxylamine sulfate, and hydroxylamine phosphate, preferably hydroxylamine sulfate, and the mass concentration of the aqueous solution of hydroxylamine salt is 10-40%, preferably 20-30%; the molar ratio of the molar mass of the hydroxylamine group in the hydroxylamine salt to the molar mass of cyclododecanone is 1.05:1-1.8:1, preferably 1.2:1-1.5:1.

[0015] In step 2) of the present application, the hydroxylamine salt solution is preheated to 80-95°C before being added to the mixed solution of step 1).

[0016] The solvent described in the present application is an alkane, including but not limited to one or more of methylcyclohexane, ethylcyclohexane, n-propylcyclohexane, isopropylcyclohexane, dimethylcyclohexane, n-dodecane, n-tetradecane, cyclododecane, decahydro naphthalene, and squalane, preferably ethylcyclohexane or isopropylcyclohexane, and the mass ratio of the solvent to cyclododecanone is 3:1-9:1, preferably 3:1-5:1.

[0017] In step 2) of the present application, ammonia is used for neutralization, and the mass concentration of the ammonia is 15-40%, preferably 18-30%.

[0018] In step 3) of the present application, the reaction time is 1-2 hours.

[0019] The alcohol ether phosphate is used as a reaction surfactant in the application, the alcohol ether phosphate can effectively reduce the surface tension of the oil phase and the water phase, increase the oil-water mixing effect, and improve the reaction rate, and the oxygen atom of the alcohol ether phosphate can form a hydrogen bond with the hydrogen of the hydroxylamine to improve the oil solubility of the hydroxylamine. The hydroxamic acid is used as a metal ion chelating agent in the application, the hydroxamic acid is an excellent metal ion chelating agent, which can chelate with metal ions such as iron, chromium and nickel in the system, reduce the content of metal ions in the system, weaken the decomposition of the hydroxylamine, and improve the utilization rate of the hydroxylamine. Meanwhile, the oxime hydroxyl of the hydroxamic acid can also form a hydrogen bond with the oxygen atom of the alcohol ether phosphate to synergistically reduce the surface tension of the system and improve the oximation reaction rate.

[0020] By using the method of the application, the reaction time of cyclododecanone oximation can be reduced to 2 hours or less, and the hydroxylamine decomposition rate can be reduced to 0.5% or less. DETAILED DESCRIPTION

[0021] The application will be further described below in conjunction with examples, and it should be noted that the examples do not constitute a limitation on the scope of protection of the application.

[0022] The detection methods used in the examples are introduced as follows:

[0023] (1) Cyclododecanone conversion rate and cyclododecanone oxime selectivity analysis

[0024] The area correction normalization method of gas chromatography is used to analyze the cyclododecanone conversion rate and selectivity in the application, and the chromatographic analysis conditions are as follows:

[0025] Instrument model: Shimadzu GC2010; chromatographic column: DB-5 (30x0.32x0.25); column temperature: programmed temperature (50℃ for 5min, then increased to 100℃ at a rate of 10℃ / min, then increased to 280℃ at a rate of 30℃ / min, and kept for 10min); injection port temperature: 230℃; FID temperature: 300℃; N2flow rate: 0.5mL / min; H2flow rate: 40mL / min; septum purge (N2) flow rate: 3mL / min; carrier gas (N2) flow rate: 1mL / min; split injection, split ratio: 50; injection volume: 0.03μL.

[0026] (2) Hydroxylamine salt content analysis

[0027] The method of industry standard JHGS 42-2016 is used to analyze the hydroxylamine salt content in the water phase in the application.

[0028] (3) Surface tension test

[0029] The multifunctional surface tension meter of Germany Dataphysics DCAT 9T is used to test the surface tension of the oximation oil and water phase in the application.

[0030] (4) Metal ion content analysis

[0031] The Agilent ICP-OES 720 was used to analyze the metal ion content in the aqueous phase.

[0032] Raw material sources:

[0033] Raw material name Manufacturer Cyclododecanone BASF Hydroxylamine sulfate Jiangsu Aikewei Isomeric tridecanol ether phosphates Jiangsu Hai'an Petrochemical Dodecanol ether phosphates Jiangsu Hai'an Petrochemical Tetracosanol ether phosphates Jiangsu Hai'an Petrochemical Salicylhydroxamic acid Hubei Dongcao Chemical Technology Co., Ltd. 1-Hydroxy-2-naphthalene methyl hydroxamic acid Hubei Dongcao Chemical Technology Co., Ltd. Benzyl hydroxamic acid Hubei Qiniu Chemical Technology Co., Ltd.

[0034] Example 1

[0035] 15 g of cyclododecanone, 45 g of ethylcyclohexane, 0.075 g of isomeric tridecanol ether phosphate, and 0.0015 g of salicylhydroxamic acid were added to a 0.5 L reaction kettle, mixed with stirring, and sampled to analyze the oil phase surface tension, which was 13 mN / m. After nitrogen replacement for 3 times, the back pressure was set to 50 KPa (G), and the temperature was raised to 90°C by oil bath.

[0036] 7.1 g of hydroxylamine sulfate was dissolved in 10.64 g of water, neutralized with 9.81 g of 15 wt% ammonia water, and preheated to 85°C after neutralization. It was added to the above reaction liquid at one time, and the reaction was started.

[0037] After 1.5 h of reaction, the stirring was stopped to separate the oil and water phases, and the oil phase was sampled for gas phase analysis. The analysis showed that the conversion rate of cyclododecanone was 99.67%, the selectivity of cyclododecanone oxime was 99.64%, and the metal ion content, surface tension, and hydroxylamine content of the aqueous phase were analyzed. The analysis showed that the metal ion (iron + chromium + nickel) content in the aqueous phase was 0.02 ppm, the surface tension was 42 mN / m, and the hydroxylamine decomposition rate was 0.29%.

[0038] Example 2

[0039] 15 g of cyclododecanone, 45 g of ethylcyclohexane, 0.075 g of isomeric tridecanol ether phosphate, and 0.0015 g of salicylhydroxamic acid were added to a 0.5 L reaction kettle, mixed with stirring, and sampled to analyze the oil phase surface tension, which was 13 mN / m. After nitrogen replacement for 3 times, the back pressure was set to 50 KPa (G), and the temperature was raised to 90°C by oil bath.

[0040] 10.31 g of hydroxylamine hydrochloride was dissolved in 92.79 g of water, neutralized with 6.3 g of 40 wt% ammonia water, and preheated to 90°C after neutralization. It was added to the above reaction liquid at one time, and the reaction was started.

[0041] After 1.3 hours of reaction, stirring was stopped to separate the oil and water phases, and the oil phase was taken for gas phase analysis. Analysis showed that the conversion rate of cyclododecanone was 99.59%, the selectivity of cyclododecanone oxime was 99.62%, the content of metal ions (iron, chromium and nickel) in the water phase was 0.04 ppm, the surface tension was 43 mN / m, and the decomposition rate of hydroxylamine was 0.35%.

[0042] Example 3

[0043] 15 g of cyclododecanone, 75 g of dimethylcyclohexane, 0.0375 g of tetradecanol ether phosphate and 0.006 g of benzylic hydroxamic acid were added to a 0.5 L reaction kettle, mixed by stirring, and sampled to analyze the surface tension of the oil phase, which was 12 mN / m. After nitrogen replacement for 3 times, the back pressure was set to 60 KPa (G), and the temperature was raised to 95°C by oil bath.

[0044] 7.58 g of hydroxylamine phosphate was dissolved in 17.68 g of water, neutralized with 7.85 g of ammonia water with a concentration of 25 wt%, and preheated to 87°C after neutralization. It was added to the above reaction solution at one time, and the reaction was started.

[0045] After 1.7 hours of reaction, stirring was stopped to separate the oil and water phases, and the oil phase was taken for gas phase analysis. Analysis showed that the conversion rate of cyclododecanone was 99.63%, the selectivity of cyclododecanone oxime was 99.57%, the content of metal ions (iron, chromium and nickel) in the water phase was 0.03 ppm, the surface tension was 41 mN / m, and the decomposition rate of hydroxylamine was 0.33%.

[0046] Comparative Example 1

[0047] 15 g of cyclododecanone and 45 g of ethylcyclohexane were added to a 0.5 L reaction kettle, mixed by stirring, and sampled to analyze the surface tension of the oil phase, which was 24 mN / m. After nitrogen replacement for 3 times, the back pressure was set to 50 KPa (G), and the temperature was raised to 90°C by oil bath.

[0048] 7.1 g of hydroxylamine sulfate was dissolved in 10.64 g of water, neutralized with 9.81 g of ammonia water with a concentration of 15 wt%, and preheated to 85°C after neutralization. It was added to the above reaction solution at one time, and the reaction was started.

[0049] After 1.5 hours of reaction, stirring was stopped to separate the oil and water phases, and the oil phase was taken for gas phase analysis. Analysis showed that the conversion rate of cyclododecanone was 32.01%, the selectivity of cyclododecanone oxime was 99.03%, the content of metal ions (iron, chromium and nickel) in the water phase was 13 ppm, the surface tension was 70 mN / m, and the decomposition rate of hydroxylamine was 15.76%.

[0050] Comparative Example 2

[0051] Into a 0.5 L reactor, 15 g of cyclododecanone, 45 g of ethylcyclohexane and 0.075 g of isomeric tridecanol ether phosphate were added, mixed with stirring, and sampled to analyze the oil phase surface tension, which was 15 mN / m. After nitrogen replacement for 3 times, the back pressure was set to 50 KPa (G), and the temperature was raised to 90°C by oil bath.

[0052] 7.1 g of hydroxylamine sulfate was dissolved in 10.64 g of water, neutralized with 9.81 g of 15 wt% ammonia water, and preheated to 85°C after neutralization. It was added to the above reaction solution at one time, and the reaction was started.

[0053] After 1.5 h of reaction, stirring was stopped to separate the oil and water phases, and the oil phase was sampled for gas phase analysis. The analysis showed that the conversion rate of cyclododecanone was 99.13%, and the selectivity of cyclododecanone oxime was 99.53%. The water phase was analyzed for metal ion content, surface tension and hydroxylamine content. The analysis showed that the metal ion (iron + chromium + nickel) content in the water phase was 12 ppm, the surface tension was 46 mN / m, and the hydroxylamine decomposition rate was 9.49%.

[0054] Comparative Example 3

[0055] Into a 0.5 L reactor, 15 g of cyclododecanone, 45 g of ethylcyclohexane and 0.0015 g of salicylhydroxamic acid were added, mixed with stirring, and sampled to analyze the oil phase surface tension, which was 23 mN / m. After nitrogen replacement for 3 times, the back pressure was set to 50 KPa (G), and the temperature was raised to 90°C by oil bath.

[0056] 7.1 g of hydroxylamine sulfate was dissolved in 10.64 g of water, neutralized with 9.81 g of 15 wt% ammonia water, and preheated to 85°C after neutralization. It was added to the above reaction solution at one time, and the reaction was started.

[0057] After 1.5 h of reaction, stirring was stopped to separate the oil and water phases, and the oil phase was sampled for gas phase analysis. The analysis showed that the conversion rate of cyclododecanone was 99.13%, and the selectivity of cyclododecanone oxime was 99.53%. The water phase was analyzed for metal ion content, surface tension and hydroxylamine content. The analysis showed that the metal ion (iron + chromium + nickel) content in the water phase was 12 ppm, the surface tension was 46 mN / m, and the hydroxylamine decomposition rate was 9.49%.

Claims

1. A process for the cyclododecanone oxime formation, characterized in that, Includes the following steps: 1) Mix cyclododecanone, solvent, surfactant and metal ion chelating agent, purge with nitrogen, pressurize to 50-80 kPa(G) and heat to 90-100°C in an oil bath; 2) Dissolve hydroxylamine salt in water, neutralize with an alkaline solution, preheat, and then add to the mixed solution in step 1); 3) After the reaction is complete, stop stirring and proceed with oil-water phase separation to obtain cyclododecanone oxime; The surfactant is an alcohol ether phosphate ester, and the metal ion chelating agent is hydroxamic acid.

2. The method of claim 1, wherein, The surfactant is selected from isomeric tridecyl ether phosphate, dodecyl ether phosphate, and dodecyltetradecyl ether phosphate.

3. The method of claim 2, wherein, The surfactant is selected from isotridecyl ether phosphate or dodecyl ether phosphate.

4. The method of claim 1, wherein, The amount of alcohol ether phosphate ester used is 0.01-0.5% of the mass of cyclododecanone.

5. The method of claim 4, wherein, The amount of alcohol ether phosphate used is 0.1-0.3% of the mass of cyclododecanone.

6. The method of claim 1, wherein, The hydroxamic acid is selected from one or more of salicylic acid, benzoyl hydroxamic acid, octyl hydroxamic acid, 1-hydroxy-2-naphthomethyl hydroxamic acid, acetyl hydroxamic acid, L-asparagine-B-isohydroxamic acid, benzyl isohydroxamic acid, and octyl isohydroxamic acid.

7. The method of claim 6, wherein, The hydroxamic acid mentioned is salicylic acid or 1-hydroxy-2-naphthomic acid.

8. The method of claim 1, wherein, The amount of hydroxamic acid used is 0.01-0.1% of the mass of cyclododecanone.

9. The method of claim 8, wherein, The amount of hydroxamic acid used is 0.02-0.05% of the mass of cyclododecanone.

10. The method of claim 1, wherein, The hydroxylamine salts mentioned include one or more of hydroxylamine hydrochloride, hydroxylamine sulfate, and hydroxylamine phosphate.

11. The method of claim 10, wherein, The hydroxylamine salt mentioned is hydroxylamine sulfate.

12. The method of claim 1, wherein, The molar ratio of hydroxylamine groups to cyclododecanone in hydroxylamine salts is 1.05:1 to 1.8:

1.

13. The method of claim 12, wherein, The molar ratio of hydroxylamine groups to cyclododecanone in hydroxylamine salts is 1.2:1 to 1.5:

1.

14. The method of claim 1, wherein, In step 2), the hydroxylamine salt solution is preheated to 80-95°C before being added to the mixed solution in step 1).

15. The method of claim 1, wherein, The solvent is an alkane, including one or more of methylcyclohexane, ethylcyclohexane, n-propylcyclohexane, isopropylcyclohexane, dimethylcyclohexane, n-dodecane, n-tetradecane, cyclododecane, decahydronaphthalene, and squalane.

16. The method of claim 15, wherein, The solvent is ethylcyclohexane or isopropylcyclohexane.

17. The method of claim 1, wherein, The mass ratio of solvent to cyclododecanone is 3:1-9:

1.

18. The method of claim 17, wherein, The mass ratio of solvent to cyclododecanone is 3:1-5:

1.

19. The method of claim 1, wherein, In step 2), ammonia water is used for neutralization, and the mass concentration of ammonia water is 15-40%.

20. The method of claim 1, wherein, In step 3), the reaction time is 1-2 hours.