A method for hydrolyzing 10-aminodecanenitrile

Abstract

The present invention discloses a hydrolysis method of 10-aminodecanenitrile, comprising the following steps: (1) putting the decanedinitrile hydrogenation product containing 10-aminodecanenitrile after removing the solvent into a hydrolysis kettle, starting stirring, heating to 110-130 °C, adding an appropriate amount of alkali solution to reach a certain alkali concentration, and maintaining this alkali solution concentration for hydrolysis reaction; (2) after the hydrolysis reaction is completed, cooling to 65-85 °C, adding a quantitative extractant to extract decanediamine and a small amount of 10-aminodecimine and bisdecimine in the system, and separating them; (3) slowly adding acid to neutralize the aqueous phase after extraction separation, controlling an appropriate pH value to precipitate 10-aminodecanoic acid, and obtaining 10-aminodecanoic acid by solid-liquid separation. The present invention hydrolyzes the decanedinitrile hydrogenation product, then extracts amine substances such as decanediamine, acidifies with acid, and separates to obtain 10-aminodecanoic acid. The process flow of the present invention is short, the operation is simple, and the purity is high.

Description

Technical Field

[0001] The present invention belongs to the technical field of fine chemical products, and particularly relates to a method for hydrolyzing 10-aminodecanenitrile. Background Art

[0002] ω-amino acids belong to fine chemical products and are a kind of chemical raw materials with relatively wide uses. Some products are also monomers for synthesizing AB-type nylon, and AB-type nylon is an engineering plastic with excellent comprehensive properties.

[0003] The method for synthesizing ω-amino acids has the invention patent CN102307848 A, a method for synthesizing ω-amino acids or esters from monounsaturated fatty acids or esters. The process target is a method for synthesizing ω-aminocarboxylic acids or their esters from monounsaturated natural fatty acids through monounsaturated dinitrile type intermediate compounds. This method is only a method for producing ω-amino acids from specific raw materials, monounsaturated fatty acids or esters. The process flow is long, the operation is cumbersome, and the yield is not high.

[0004] As a kind of long carbon chain AB-type nylon, nylon 10 has excellent physical, mechanical and mechanical properties. Since there is currently no engineering method for preparing the monomer (10-aminodecanoic acid) of nylon 10, there is no nylon 10 product sold on the market. Therefore, it is necessary to develop a method for preparing 10-aminodecanoic acid. Summary of the Invention

[0005] The purpose of the present invention is to overcome the deficiencies existing in the prior art and provide a method for hydrolyzing 10-aminodecanenitrile. The present invention hydrolyzes the hydrogenation product of sebaconitrile (co-producing 10-aminodecanenitrile) to obtain 10-aminodecanoate, adds n-butanol to extract decanediamine and a small amount of 10-aminodecimine and bisdecimine, and then acidifies and separates the remaining materials to obtain 10-aminodecanoic acid. The process flow of the present invention is short, the operation is simple, and the yield is high.

[0006] To achieve the above technical purposes, the technical solution adopted in the embodiment of the present invention is: a method for hydrolyzing 10-aminodecanenitrile, comprising the following steps:

[0007] (1) Put the hydrogenation product of sebaconitrile containing 10-aminodecanenitrile after removing the solvent into a hydrolysis kettle, start stirring, raise the temperature to 110-130 °C, add an appropriate amount of alkali solution to reach a certain alkali concentration, and maintain this alkali solution concentration for the hydrolysis reaction;

[0008] (2) After the hydrolysis reaction is completed, cool down to 65-85 °C, add a quantitative extractant to extract decanediamine and a small amount of 10-aminodecimine and bisdecimine in the system, and separate them;

[0009] (3) After extraction and separation, slowly add acid to neutralize the aqueous phase, control the appropriate pH value to precipitate 10-aminodecanoic acid, and obtain 10-aminodecanoic acid by solid-liquid separation.

[0010] Further, the hydrogenation product containing 10-aminodecanenitrile is the product obtained by co-producing 10-aminodecanenitrile by hydrogenation of adiponitrile. The hydrogenation product contains 10-aminodecanenitrile, decanediamine, 10-aminodecaimine, and bis-decaimine components, and the mass content of 10-aminodecanenitrile is 30-45%.

[0011] The product obtained by co-producing 10-aminodecanenitrile by hydrogenation of adiponitrile in step (1) is a system with relatively special physical properties. Because the main components in the hydrogenation product system of adiponitrile are 10-aminodecanenitrile, decanediamine, and a small amount of bis-decaimine and 10-aminodecaimine, among which 10-aminodecanenitrile is insoluble in aqueous media and thus cannot be directly dissolved in water and alkaline solutions. However, decanediamine and a small amount of bis-decaimine and 10-aminodecaimine are miscible with water or low-concentration alkaline solutions when the system temperature reaches above 65°C. Therefore, when the products such as decanediamine and imines are dissolved in the alkaline solution, the phase compatibility of the system changes fundamentally, and 10-aminodecanenitrile can be dissolved in it to approach a homogeneous phase.

[0012] As described above, to strengthen the dissolution process, an axial flow turbine impeller is equipped in the hydrolysis kettle, which has good shearing and mixing functions, and the stirring speed is controlled at 200-300 r / min.

[0013] Further, the alkaline solution in step (1) is a strong alkaline solution, using sodium hydroxide solution and / or potassium hydroxide solution, preferably sodium hydroxide solution.

[0014] Further, the alkali concentration of the system after adding the alkaline solution in step (1) is 1.5-3.5%, and the alkali concentration of the system is maintained at 1.5-3.5% during the hydrolysis reaction process. Since a certain alkali concentration needs to be maintained for the hydrolysis of 10-aminodecanenitrile to 10-aminodecanoic acid, the reaction system can proceed smoothly. When the alkali concentration is less than 1.5%, the concentration of hydroxide ions in the system is low, the reaction rate is slow, and the time consumption is too long; when the alkali concentration is greater than 3.5%, the high alkali concentration will produce a common ion effect, affecting the phase compatibility of the system, and even extruding 10-aminodecanenitrile, making the hydrolysis reaction difficult.

[0015] As described above, 10-aminodecanoic acid generated during the hydrolysis process continuously consumes the alkaline solution. To promote the reaction, it is necessary to continuously replenish the alkaline solution so that the alkaline solution and the organic matter can be miscible in the system.

[0016] In the hydrogenation product containing 10-aminodecanenitrile in step (1), the molar ratio of 10-aminodecanenitrile to the solute in the alkaline solution is 1:1.1-1.2.

[0017] When the molar ratio of the alkali solution to the hydrogenation product containing 10-aminodecanenitrile is less than 1:1.1, due to the small amount of alkali solution, which is close to the theoretical addition amount, the contact opportunity between 10-aminodecanenitrile molecules and the alkali is small, the hydrolysis reaction slows down, and even cannot react completely; 10-aminodecanenitrile can dissolve in the system because when the system temperature reaches above 65 °C, decanediamine is miscible with the alkali solution, and the system becomes lipophilic; on the contrary, when the alkali solution is greater than 1:1.2 with the hydrogenation product of 10-aminodecanenitrile, in the miscible system of decanediamine and the alkali solution, due to the excessive amount of the alkali solution, the dissolution ability of 10-aminodecanenitrile decreases due to the extrusion effect. When the amount of the alkali solution is particularly large, two-phase separation may even occur.

[0018] The hydrolysis temperature in step (1) is 110 - 130 °C; the hydrolysis temperature is set at 110 - 130 °C: because when the temperature is lower than 110 °C, the hydrolysis rate constant of 10-aminodecanenitrile decreases, the reaction rate is significantly slower, and the reaction is not easy to proceed; when the hydrolysis temperature is higher than 130 °C, due to the presence of imine unsaturated hydrogenation products in the system, it is extremely easy to become by-products, and even when the temperature is too high, the materials in the system may undergo a polymerization reaction, resulting in a decrease in the yield of 10-aminodecanoic acid or inability to separate.

[0019] Furthermore, the hydrolysis reaction time in step (1) is 6 - 8 h; from the reaction mechanism, the hydrolysis reaction of 10-aminodecanenitrile to form 10-aminodecanoic acid is divided into two steps: the first step is the hydrolysis of the nitrile group to form an amide group, and this step of the reaction is relatively easy and fast; the second step is the further hydrolysis of the generated amide group into an acid group, which requires high activation energy, is slow, and takes a long time. Without strengthening conditions, it is 1 - 2 orders of magnitude slower than the one-step reaction. Therefore, to ensure the hydrolysis reaction is complete, the time is set at 6 - 8 h; the test data shows that when the time is less than 6 h, the hydrolysis reaction may not be complete and the yield decreases; when the reaction time reaches 8 h, the hydrolysis is already complete.

[0020] Furthermore, the extractant in step (2) is n-butanol. The reason for using n-butanol to extract decanediamine is that after the hydrolysis of the hydrogenation product of adiponitrile, it is mainly 10-aminodecanoic acid and decanediamine, containing a small amount of diimine, amine imine, and an extremely small amount of sebacic acid; among them, sebacic acid and 10-aminodecanoic acid react with the alkali solution to form salts and dissolve in the system. Decanediamine and imine have greater solubility in n-butanol, especially prior to the alkali solution system, and there is an obvious phase boundary between n-butanol and the low-concentration aqueous alkali solution.

[0021] The mass ratio of the extractant to the hydrogenation product of adiponitrile in step (2) is 0.6 - 0.9:1. As an extractant, n-butanol not only needs to consider compatibility and extraction efficiency but also subsequent separation operations. When the mass ratio is lower than 0.6:1, the demarcation effect between the extraction phase and the alkali solution is not good; on the contrary, when the mass ratio is greater than 0.9:1, the dosage is large and uneconomical.

[0022] In step (2), the extraction temperature is controlled within the range of 65 to 85 °C. There are two purposes for this step: on the one hand, the solubility of diamine in the aqueous phase under different temperature conditions needs to be considered (i.e., the influence of temperature on the distribution coefficient of decanediamine between the extraction phase and the aqueous phase); on the other hand, the viscosity and mass transfer ability of the entire hydrolysis system need to be taken into account, that is, it is beneficial to the extraction effect of n-butanol on decanediamine in the hydrolysis reaction products. When the temperature of the hydrolysis product system drops below 65 °C, the consistency of the system increases, which is not conducive to mass transfer and increases the difficulty of extraction. It is necessary to make up for it by extending the extraction time and the intensity of stirring. When the temperature of the hydrolysis product system is controlled above 85 °C, the solubility of decanediamine in the system gradually increases with the increase of temperature, and the extraction efficiency will decrease. At this time, when extracting with n-butanol, the extraction difficulty increases and it is not easy to extract.

[0023] In step (3), the pH of the system after adding acid for neutralization is 6.7 to 6.9. The reaction end point is selected as pH 6.7 to 6.9 because when the acid addition for neutralization reaches pH 6.9, 10-aminodecanoate in the hydrolysis product reacts completely with the acid to be converted into 10-aminodecanoic acid. When the acid addition for neutralization is excessive and the pH value is less than 6.8, the amino group of 10-aminodecanoic acid will react with the acid to form a salt and dissolve back into the product system again, and the effective separation of 10-aminodecanoic acid cannot be achieved.

[0024] The dilute acid used for neutralization in step (3) is dilute hydrochloric acid or dilute sulfuric acid, and the specific concentration is not limited as long as it can be used to adjust the pH value.

[0025] The beneficial effects brought by the technical solution provided by the embodiments of the present invention are as follows:

[0026] 1. Without changing the existing process conditions of decanediamine hydrogenation, the present invention only adjusts some hydrogenation process conditions to co-produce the hydrogenation intermediate 10-aminodecanenitrile. Without separation, the mixture is directly hydrolyzed and then extracted and separated to obtain 10-aminodecanoic acid. The process is simple and easy to operate.

[0027] 2. The hydrogenation products of the present invention are mainly a mixture of decanediamine and 10-aminodecanenitrile, and also contain a small amount of diimine, aminoimine and an extremely small amount of decanedinitrile, which are very difficult to separate by distillation process. Based on the characteristics of the system, the inventor directly hydrolyzes the mixture without separation and cleverly selects n-butanol as the extractant to efficiently extract amines such as decanediamine, diimine and aminoimine in the hydrolyzed mixture system. Only the salt solution of 10-aminodecanoic acid is in the aqueous phase, with high purity. After acidification and separation, the product is obtained, avoiding the separation difficulties in engineering.

[0028] 3. The 10-aminodecanoic acid prepared according to the present invention has a single component and high purity, and can be directly used for synthesizing nylon 10, enriching the varieties of the nylon family. Specific Embodiments

[0029] In order to make the objectives, technical solutions and advantages of the present invention more clear and understandable, the present invention will be further described in detail below in conjunction with embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0030] Example 1

[0031] A method for hydrolyzing 10-aminodecanenitrile, comprising the following steps:

[0032] (1) After removing the solvent ethanol, 1151 g of the adiponitrile hydrogenation product containing 38.2 wt.% of 10-aminodecanenitrile was put into a hydrolysis kettle, the stirring was started, the temperature was raised to the set temperature of 124 °C, 1225 g of sodium hydroxide solution was added, and the alkali concentration of the system was maintained at 3% (total alkali supplement 74 g), and the hydrolysis reaction was carried out for 7.5 h;

[0033] (2) After the hydrolysis reaction was completed, the temperature was lowered to 80 °C, 805 g of n-butanol was added for extraction, and after standing and separating, an extraction phase mainly composed of decanediamine and containing a small amount of 10-aminodecimine and bisdecimine and an alkali liquid phase were obtained;

[0034] (3) Acid was slowly added to the water phase after extraction separation until the pH reached 6.8, 10-aminodecanoic acid was precipitated, and 483.5 g of 10-aminodecanoic acid was obtained by filtration separation. The yield of 10-aminodecanoic acid was 98.8%, and the purity was 99.8%.

[0035] Example 2 (changing the alkali concentration within the allowable range of the present invention, and the other conditions are the same as in Example 1)

[0036] A method for hydrolyzing 10-aminodecanenitrile, comprising the following steps:

[0037] (1) After removing the solvent ethanol, 1151 g of the adiponitrile hydrogenation product containing 38.2 wt.% of 10-aminodecanenitrile was put into a hydrolysis kettle, the stirring was started, the temperature was raised to the set temperature of 124 °C, 1225 g of sodium hydroxide solution was added, and the alkali concentration was maintained at 2% (total alkali supplement 85 g), and the hydrolysis was completed in 7.5 h;

[0038] (2) After the hydrolysis reaction was completed, the temperature was lowered to 80 °C, 805 g of n-butanol was added for extraction, and after standing and separating, an extraction phase containing decanediamine and a small amount of 10-aminodecimine and bisdecimine was obtained;

[0039] (3) Acid was slowly added to the water phase after extraction separation until the pH reached 6.8, 10-aminodecanoic acid was precipitated, and 479.8 g of 10-aminodecanoic acid was obtained by filtration separation. The yield of 10-aminodecanoic acid was 98.04%, and the purity was 99.8%.

[0040] Example 3 (changing the hydrolysis time within the scope permitted by the present invention, with the remaining conditions the same as in Example 1)

[0041] A method for hydrolyzing 10-aminodecanenitrile, comprising the following steps:

[0042] (1) After removing the solvent ethanol, 1151 g of the adiponitrile hydrogenation product containing 38.2 wt.% of 10-aminodecanenitrile was put into a hydrolysis kettle, stirring was started, the temperature was raised to the set temperature of 124 °C, 1225 g of sodium hydroxide solution was added, and the concentration of this alkali solution was maintained at 3% (total additional alkali 74 g), and the reaction was completed after hydrolysis for 6.5 h;

[0043] (2) After the hydrolysis reaction ended, the temperature was lowered to 80 °C, 805 g of n-butanol was added for extraction, and after standing and separating, an extraction phase containing decanediamine, and a small amount of 10-aminodecimine and bisdecimine was obtained;

[0044] (3) Acid was slowly added to the aqueous phase after extraction separation to neutralize to pH 6.8, 10-aminodecanoic acid was precipitated, and 481.2 g of 10-aminodecanoic acid was obtained by filtration separation. The yield of 10-aminodecanoic acid was 98.3%, and the purity was 99.7%.

[0045] Example 4 (changing the hydrolysis temperature within the scope permitted by the present invention, with the remaining conditions the same as in Example 1)

[0046] A method for hydrolyzing 10-aminodecanenitrile, comprising the following steps:

[0047] (1) After removing the solvent ethanol, 1151 g of the adiponitrile hydrogenation product containing 38.2 wt.% of 10-aminodecanenitrile was put into a hydrolysis kettle, stirring was started, the temperature was raised to the set temperature of 116 °C, 1225 g of sodium hydroxide solution was added, and the concentration of this alkali solution was maintained at 3% (total additional alkali 74 g), and the reaction was completed after hydrolysis for 7.5 h;

[0048] (2) After the hydrolysis reaction ended, the temperature was lowered to 80 °C, 805 g of n-butanol was added for extraction, and after standing and separating, an extraction phase containing decanediamine, and a small amount of 10-aminodecimine and bisdecimine was obtained;

[0049] (3) Acid was slowly added to the aqueous phase after extraction separation to neutralize to pH 6.8, 10-aminodecanoic acid was precipitated, and 481.8 g of 10-aminodecanoic acid was obtained by filtration separation. The yield of 10-aminodecanoic acid was 98.4%, and the purity was 99.8%.

[0050] Example 5 (changing the extraction temperature within the scope permitted by the present invention, with the remaining conditions the same as in Example 1)

[0051] A method for hydrolyzing 10-aminodecanenitrile, comprising the following steps:

[0052] (1) After removing the solvent ethanol, 1151 g of the adiponitrile hydrogenation product containing 38.2 wt.% of 10-aminodecanenitrile was put into a hydrolysis kettle, the stirring was started, the temperature was raised to the set temperature of 116 °C, 1225 g of sodium hydroxide solution was added, and the concentration of this alkali solution was maintained at 3% (total alkali supplementation 74 g), and the reaction was completed after hydrolysis for 7.5 h;

[0053] (2) After the hydrolysis reaction was completed, the temperature was lowered to 71 °C, 805 g of n-butanol was added for extraction, and after standing and separating, an extraction phase containing decanediamine, and a small amount of 10-aminodecimine and bisdecimine was obtained;

[0054] (3) After extraction and separation, acid was slowly added to the aqueous phase to neutralize to pH 6.8, 10-aminodecanoic acid was precipitated, and 482.8 g of 10-aminodecanoic acid was obtained by filtration separation. The yield of 10-aminodecanoic acid was 98.6%, and the purity was 99.8%.

[0055] Example 6 (Changing the pH of acid neutralization within the scope permitted by the present invention, and the other conditions are the same as those in Example 1)

[0056] A method for hydrolyzing 10-aminodecanenitrile, comprising the following steps:

[0057] (1) After removing the solvent ethanol, 1151 g of the adiponitrile hydrogenation product containing 38.2 wt.% of 10-aminodecanenitrile was put into a hydrolysis kettle, the stirring was started, the temperature was raised to the set temperature of 116 °C, 1225 g of sodium hydroxide solution was added, and the concentration of this alkali solution was maintained at 3% (total alkali supplementation 74 g), and the reaction was completed after hydrolysis for 7.5 h;

[0058] (2) After the hydrolysis reaction was completed, the temperature was lowered to 80 °C, 805 g of n-butanol was added for extraction, and after standing and separating, an extraction phase containing decanediamine, and a small amount of 10-aminodecimine and bisdecimine was obtained;

[0059] (3) After extraction and separation, acid was slowly added to the aqueous phase to neutralize to pH 6.7, 10-aminodecanoic acid was precipitated, and 483.0 g of 10-aminodecanoic acid was obtained by filtration separation. The yield of 10-aminodecanoic acid was 98.69%, and the purity was 99.6%.

[0060] Comparative Example 1 (Outside the scope permitted by the present invention, changing the alkali solution concentration to 1%, and the other conditions are the same as those in Example 1)

[0061] A method for hydrolyzing 10-aminodecanenitrile, comprising the following steps:

[0062] (1) After removing the solvent ethanol, 1151 g of the adiponitrile hydrogenation product containing 38.2 wt.% of 10-aminodecanenitrile was put into a hydrolysis kettle, the stirring was started, the temperature was raised to the set temperature of 124 °C, 1225 g of sodium hydroxide solution was added, and the concentration of this alkali solution was maintained at 1% (total alkali supplementation 97 g), and the reaction was completed after hydrolysis for 7.5 h;

[0063] After the hydrolysis reaction is completed, the temperature is lowered to 80 °C, and 805 g of n-butanol is added for extraction. After standing and separating, an extraction phase mainly containing sebac diamine, and a small amount of 10-aminodecylimine and bisdecylimine, and an alkaline liquid phase are obtained.

[0064] (3)Slowly add acid to the aqueous phase after extraction and separation until the pH reaches 6.8 to precipitate 10-aminodecanoic acid. 431.2 g of 10-aminodecanoic acid is obtained by filtration separation. The yield of 10-aminodecanoic acid is 88%, and the purity is 99.3%.

[0065] Comparative Example 2 (outside the allowable range of the present invention, the hydrolysis time is changed to 5 h, and the other conditions are the same as in Example 1)

[0066] A method for hydrolyzing 10-aminodecanenitrile, comprising the following steps:

[0067] (1)After removing the solvent ethanol, 1151 g of the hydrogenated product of adiponitrile containing 38.2 wt.% of 10-aminodecanenitrile is put into a hydrolysis kettle, stirring is started, the temperature is raised to the set temperature of 124 °C, 1225 g of sodium hydroxide solution is added, and the concentration of this alkaline solution is maintained at 3% (total additional alkali 74 g). The hydrolysis is completed after 5.0 h.

[0068] (2)After the hydrolysis reaction is completed, the temperature is lowered to 80 °C, and 805 g of n-butanol is added for extraction. After standing and separating, an extraction phase mainly containing sebac diamine, and a small amount of 10-aminodecylimine and bisdecylimine, and an alkaline liquid phase are obtained.

[0069] (3)Slowly add acid to the aqueous phase after extraction and separation until the pH reaches 6.8 to precipitate 10-aminodecanoic acid. 448.6 g of 10-aminodecanoic acid is obtained by filtration separation. The yield of 10-aminodecanoic acid is 91.6%, and the purity is 99.5%.

[0070] Comparative Example 3 (outside the allowable range of the present invention, the hydrolysis temperature is changed to 105 °C, and the other conditions are the same as in Example 1)

[0071] A method for hydrolyzing 10-aminodecanenitrile, comprising the following steps:

[0072] (1)After removing the solvent ethanol, 1151 g of the hydrogenated product of adiponitrile containing 38.2 wt.% of 10-aminodecanenitrile is put into a hydrolysis kettle, stirring is started, the temperature is raised to the set temperature of 105 °C, 1225 g of sodium hydroxide solution is added, and the concentration of this alkaline solution is maintained at 3% (total additional alkali 74 g). The hydrolysis is completed after 7.5 h.

[0073] (2)After the hydrolysis reaction is completed, the temperature is lowered to 80 °C, and 805 g of n-butanol is added for extraction. After standing and separating, an extraction phase mainly containing sebac diamine, and a small amount of 10-aminodecylimine and bisdecylimine, and an alkaline liquid phase are obtained.

[0074] (3) Slowly add acid to neutralize the aqueous phase after extraction and separation to pH 6.8, and 10-aminodecanoic acid will precipitate. 454.0 g of 10-aminodecanoic acid is obtained by filtration separation. The yield of 10-aminodecanoic acid is 92.7%, and the purity is 99.5%.

[0075] Comparative Example 4 (outside the scope allowed by the present invention, the pH value of acid addition and neutralization is changed to 6.6, and the other conditions are the same as in Example 1)

[0076] A method for hydrolyzing 10-aminodecanenitrile, comprising the following steps:

[0077] (1) After removing the solvent ethanol, 1151 g of the hydrogenation product of adiponitrile containing 38.2 wt.% of 10-aminodecanenitrile is put into a hydrolysis kettle, stirring is started, the temperature is raised to the set temperature of 124 °C, 1225 g of sodium hydroxide solution is added, and the concentration of this alkali solution is maintained at 3% (total supplementary alkali 74 g). The reaction is completed after hydrolysis for 7.5 h;

[0078] (2) After the hydrolysis reaction is completed, the temperature is lowered to 80 °C, 805 g of n-butanol is added for extraction, and after standing and separating, an extraction phase mainly containing decanediamine and a small amount of 10-aminodecaimine and bisdecaimine and an alkali liquid phase are obtained;

[0079] (3) Slowly add acid to neutralize the aqueous phase after extraction and separation to pH 6.6, and 10-aminodecanoic acid will precipitate. 434.3 g of 10-aminodecanoic acid is obtained by filtration separation. The yield of 10-aminodecanoic acid is 88.7%, and the purity is 99.2%.

[0080] From the yields of the 10-aminodecanoic acid products prepared in Examples 1-6 above, it can be found that the yield of the 10-aminodecanenitrile hydrolysis method of the present invention is stable and the purity is high; from the yields of the 10-aminodecanoic acid products obtained in Comparative Examples 1-4, after deviating from the process parameters of the present invention, the yields and purities of the products all decrease to a certain extent.

[0081] The hydrogenation product of adiponitrile containing 10-aminodecanenitrile in Examples 1-6 and Comparative Examples 1-4 is obtained by a method for co-producing 10-aminodecanenitrile. The hydrogenation product contains components such as 10-aminodecanenitrile, decanediamine, 10-aminodecaimine, and bisdecaimine, and the mass content of 10-aminodecanenitrile in the hydrogenation product is 30-45%;

[0082] Among them, the method for co-producing 10-aminodecanenitrile:

[0083] Put adiponitrile, ethanol, catalyst and cocatalyst into a hydrogenation reactor in proportion, start stirring after nitrogen replacement, hydrogenate at a given temperature and pressure, terminate the reaction after a certain time, and further remove the solvent to obtain a hydrogenation product containing 10-aminodecanenitrile and decanediamine.

[0084] The above are only the preferred embodiments of the present invention and do not impose any limitations on the present invention. Any simple modifications, changes, and equivalent variations made to the above embodiments based on the essence of the present invention still fall within the scope of protection of the technical solution of the present invention.

Claims

1. A method for hydrolyzing 10-aminodecanenitrile, characterized in that, It includes the following steps: (1) Put the hydrogenation product of dodecanedinitrile containing 10-aminodecanenitrile after removing the solvent into a hydrolysis kettle, start stirring, raise the temperature to 110-130 °C, add an appropriate amount of alkali solution to reach a certain alkali concentration, and maintain this alkali concentration for the hydrolysis reaction; (2) After the hydrolysis reaction is completed, cool down to 65-85 °C, add a quantitative extraction agent to extract decanediamine and a small amount of 10-aminodecylimine and bisdecylimine in the system, and separate them; (3) Slowly add acid to neutralize the aqueous phase after extraction and separation, control the appropriate pH value to precipitate 10-aminodecanoic acid, and obtain 10-aminodecanoic acid by solid-liquid separation; The extraction agent described in step (2) is n-butanol.

2. The hydrolysis method of 10-aminodecanenitrile according to claim 1, characterized in that, The hydrogenation product containing 10-aminodecanenitrile is the product obtained by co-producing 10-aminodecanenitrile by hydrogenating dodecanedinitrile. The hydrogenation product contains components of 10-aminodecanenitrile, decanediamine, 10-aminodecylimine and bisdecylimine, and the mass content of 10-aminodecanenitrile is 30-45%.

3. The hydrolysis method of 10-aminodecanenitrile according to claim 1, characterized in that, The alkali solution described in step (1) is a strong alkali solution, using sodium hydroxide solution and / or potassium hydroxide solution.

4. The hydrolysis method of 10-aminodecanenitrile according to claim 1, characterized in that, The alkali concentration of the system after adding the alkali solution in step (1) is 1.5-3.5%, and the alkali solution concentration of the system is maintained at 1.5-3.5% during the hydrolysis reaction.

5. The hydrolysis method of 10-aminodecanenitrile according to claim 1, wherein The molar ratio of 10-aminodecanenitrile in the hydrogenation product containing 10-aminodecanenitrile to the solute in the alkali solution in step (1) is 1:1.1-1.

2.

6. The hydrolysis method of 10-aminodecanenitrile according to claim 1, characterized in that, The hydrolysis reaction time described in step (1) is 6-8 h.

7. The hydrolysis method of 10-aminodecanenitrile according to claim 1, characterized in that, The mass ratio of the extraction agent to the hydrogenation product of dodecanedinitrile in step (2) is 0.6-0.9:

1.

8. The hydrolysis method of 10-aminodecanenitrile according to claim 1, characterized in that, The pH of the system after adding acid for neutralization in step (3) is 6.7-6.

9.

9. The hydrolysis method of 10-aminodecanenitrile according to claim 1, characterized in that, Hydrochloric acid or sulfuric acid is added during acid addition for neutralization in step (3).