Amonolysis process of high-yield taurine

Abstract

The invention discloses an ammonolysis process of high-yield taurine, and relates to the technical field of ammonolysis of taurine. The ammonia water complexing ion catalyst is added into the reaction liquid, a common ammonolysis process is replaced by a microwave ammonolysis process, the filtrate is subjected to high-temperature spray drying treatment, byproducts are removed, and the filtrate is reused as mother liquor, so that the temperature pressure and the reaction time during ammonolysis are reduced, the reaction conditions are milder, and the yield is higher. Meanwhile, by-products are reduced, the yield of the taurine and the ammonolysis efficiency are comprehensively improved, and the environmental problem caused by the residual by-products is avoided; the aluminum oxide in the ammonia water complexing ion catalyst is high in hardness and strength and stable in chemical property, can effectively resist abrasion and crushing in the catalysis process, prolongs the service life, can be recycled and has certain economic benefits.

Description

Technical Field

[0001] The invention relates to the technical field of taurine production, in particular to an ammonolysis process of taurine with high yield. Background Art

[0002] Taurine, chemically known as 2-aminoethanesulfonic acid, is an indispensable non-protein amino acid for humans and animals. It exists in a free state in various organs of the human body and mammals, and plays a key role in promoting the growth and development of the nervous system. As a multifunctional compound, taurine has shown a wide range of application value in many fields such as food, health, and medicine, and is used as a nutritional enhancer and organic synthesis intermediate. Its unique pharmacological and nutritional health effects make taurine a highly anticipated fine chemical in the market.

[0003] There are currently two methods for preparing taurine, namely the ethanolamine method and the ethylene oxide method. The ethylene oxide method has lower costs than the ethanolamine method, but produces more by-products during the ammonolysis process, resulting in low ammonolysis reaction efficiency, more impurities in the mother liquor, and poor separation effect. 2 MoO 4 (PO4) 2 、ZrMo 2 O 8 Although heterogeneous catalysts such as 2-nitrogen ...

[0004] Therefore, we propose a high-yield taurine aminolysis process to solve the problems raised in the above background technology, reduce reaction by-products and reduce costs. Summary of the invention

[0005] The object of the present invention is to provide a high-yield taurine aminolysis process to solve the problems raised in the prior art.

[0006] To achieve the above object, the present invention provides the following technical solution: a high-yield taurine ammonolysis process, comprising the following steps: Step (1): mixing an aqueous sodium hydroxyethyl sulfonate solution, aqueous ammonia and an aqueous ammonia complex ion catalyst, and stirring the mixture to obtain a reaction solution; Step (2): subjecting the reaction solution obtained in step (1) to a microwave ammonolysis reaction to obtain a sodium aminosulfonate solution; Step (3): removing ammonia from the sodium aminosulfate solution obtained in step (2), adjusting the pH to 7-9, and obtaining a crude taurine product and a filtrate after crystallization and filtration; Step (4): The filtrate obtained in step (3) is subjected to high-temperature spray drying treatment, and the obtained solid product is prepared into an aqueous solution, which is reused in step (1) as the mother liquor, and steps (1) to (3) are repeated until the effective ingredients in the mother liquor are completely reacted to obtain taurine.

[0007] Furthermore, in step (1), the mass ratio of sodium isethionate to aqueous ammonia is 1:(10-20); The mass ratio of sodium hydroxyethyl sulfonate to ammonia complex ion catalyst is 1:(0.05-0.1).

[0008] Furthermore, the concentration of the sodium isethionate aqueous solution in step (1) is 30-50%; The concentration of the ammonia water is 25-28%.

[0009] Furthermore, the aminolysis reaction in step (2) is carried out under the action of microwaves, and the reaction conditions are: frequency 915 MHZ; time 0.5-5 min; temperature 80-120° C., and pressure 0.2-3 MPa.

[0010] Furthermore, the temperature of the ammonia removal in step (3) is 155-185°C; The process conditions for the crystallization in step (3) are: temperature 20-40°C, time 3-5h.

[0011] Furthermore, the conditions for high temperature spray drying in step (4) are: inlet air temperature 200-240°C, outlet air temperature 80-120°C, and pressure 5-10 kPa.

[0012] Further, sodium isethionate, CAS No. 107-36-8, was sourced from Shanghai Yuanye Biotechnology Co., Ltd.; Ammonia water, CAS No. 1336-21-6, was obtained from Jinan Yuanhai Chemical Co., Ltd.

[0013] In the above technical scheme, the ammonolysis is carried out by microwave process, the by-products are reduced, the ammonolysis efficiency is improved, and the yield of taurine is improved; the reason is that: in the reaction system of sodium isethionate and ammonia, the raw materials used are polar substances, the dielectric constant and dipole of which are relatively large, and the reaction system exists in an ionic state, which has a strong ability to absorb and conduct microwaves; microwaves activate ammonia, hydroxyl groups and water in the reaction solution, accelerating the reaction; when sodium isethionate reacts with ammonia to form sodium taurine, microwaves make the reaction easily affected by bond angles and steric hindrance, thereby greatly reducing the generation of by-products, such as sodium di-taurate and sodium tri-taurate; By recycling and reusing the mother liquor, the yield of taurine is increased and environmental problems caused by residual by-products are avoided.

[0014] Furthermore, the ammonia complex ion catalyst in step (1) is prepared by the following process: Alumina and sodium citrate are mixed, ultrasonically dispersed, stirred for 6-24 hours, and then ammonia water is added to adjust the pH to 11-13, and the mixture is sealed and stirred for 6-24 hours to obtain an ammonia water complex ion catalyst.

[0015] Furthermore, the mass ratio of aluminum oxide to sodium citrate is 1:(0.5-0.8).

[0016] Furthermore, the ultrasonic dispersion time is 10-60 min.

[0017] Further, alumina, CAS No. 1344-28-1, specific surface area 150-200m 2 / g, from Beijing Dekedaojin Technology Co., Ltd.; Sodium citrate, CAS No. 68-04-2, is from Errek (Shandong) Chemical Group Co., Ltd.

[0018] In the above technical scheme, an ammonia complex ion catalyst is formed by ammonia water and alumina, so that the conditions of the ammonolysis reaction are milder, and the reaction temperature, pressure and ammonolysis time are shorter; the complex ion catalyst formed by alumina and ammonia water has a large surface area, can provide more active sites, increase the contact opportunities between reactants and catalysts, and thus improve the efficiency of ammonolysis; and alumina has high hardness and strength, and stable chemical properties, can effectively resist wear and breakage during the catalytic process, extend its service life, can be recycled and reused, and has certain economic benefits.

[0019] Compared with the prior art, the present invention has the following beneficial effects: 1. Ammonolysis is performed by microwave technology, which reduces by-products, improves the efficiency of ammonolysis, and increases the yield of taurine. The reason is that in the reaction system of sodium hydroxyethyl sulfonate and ammonia, the raw materials used are polar substances with relatively large dielectric constants and dipoles, and the reaction system exists in an ionic state, which has a strong ability to absorb and conduct microwaves. Microwaves activate ammonia, hydroxyl groups, and water in the reaction solution to accelerate the reaction. When sodium hydroxyethyl sulfonate reacts with ammonia to form sodium taurine, microwaves make the reaction easily affected by bond angles and steric hindrance, thereby greatly reducing the generation of by-products, such as sodium di-taurate and sodium tri-taurate.

[0020] 2. By forming an ammonia complex ion catalyst through ammonia water and alumina, the conditions of the ammonolysis reaction are milder, and the reaction temperature, pressure and ammonolysis time are shorter; the complex ion catalyst formed by alumina and ammonia water has a large surface area, which can provide more active sites and increase the contact opportunities between reactants and catalysts, thereby improving the efficiency of ammonolysis; and alumina has high hardness and strength, and stable chemical properties. It can effectively resist wear and breakage during the catalytic process, extend its service life, can be recycled and reused, and has certain economic benefits.

[0021] 3. By recycling and reusing the mother liquor, the yield of taurine is improved and environmental problems caused by residual by-products are avoided. DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] In the following specific implementations, Sodium isethionate, CAS No. 107-36-8, from Shanghai Yuanye Biotechnology Co., Ltd.; Ammonia water, CAS No. 1336-21-6, was obtained from Jinan Yuanhai Chemical Co., Ltd.; Alumina, CAS No. 1344-28-1, surface area 150-200m 2 / g, from Beijing Dekedaojin Technology Co., Ltd.; Sodium citrate, CAS No. 68-04-2, is from Errek (Shandong) Chemical Group Co., Ltd.

[0024] Example 1: A high-yield taurine ammonolysis process comprising the following steps: 1. Preparation of ammonia complex ion catalyst: Alumina and sodium citrate were mixed, ultrasonically dispersed, stirred for 6 hours, and then ammonia water was added to adjust the pH to 11, and the mixture was sealed and stirred for 6 hours to obtain an ammonia complex ion catalyst; the mass ratio of alumina to sodium citrate was 1:0.5; and the ultrasonic dispersion time was 10 minutes.

[0025] 2. Preparation of taurine: Step (1): mixing an aqueous sodium hydroxyethyl sulfonate solution, ammonia water and an ammonia water complex ion catalyst, stirring them uniformly to obtain a reaction solution; step (2): subjecting the reaction solution obtained in step (1) to a microwave ammonolysis reaction to obtain a sodium aminosulfonate solution; step (3): removing ammonia from the sodium aminosulfonate solution obtained in step (2), adjusting the pH to 7, and filtering the solution after crystallization to obtain a crude taurine product and a filtrate; step (4): subjecting the filtrate obtained in step (3) to a high-temperature spray drying treatment, and preparing the obtained solid product into an aqueous solution, which is then recycled to step (1) as a mother liquor, and steps (1) to (3) are repeated until the effective components in the mother liquor are completely reacted to obtain taurine; step (5): removing ammonia from the sodium aminosulfonate solution obtained in step (2), adjusting the pH to 7, and filtering the solution after crystallization to obtain a crude taurine product and a filtrate; step (4): subjecting the filtrate obtained in step (3) to a high-temperature spray drying treatment, and preparing the obtained solid product into an aqueous solution, which is then recycled to step (1) as a mother liquor, and steps (1) to (3) are repeated until the effective components in the mother liquor are completely reacted to obtain taurine; The mass ratio of sodium hydroxyethyl sulfonate to aqueous ammonia in step (1) is 1:10; the mass ratio of sodium hydroxyethyl sulfonate to aqueous ammonia complex ion catalyst is 1:0.05; the concentration of aqueous sodium hydroxyethyl sulfonate in step (1) is 30%; the concentration of aqueous ammonia is 25%; the ammonolysis reaction in step (2) is carried out under the action of microwaves, and the reaction conditions are: frequency 915 MHZ; time 0.5 min; temperature 80°C, pressure 0.2 MPa; the temperature for removing ammonia in step (3) is 155°C; the process conditions for crystallization in step (3) are: temperature 20°C, time 3 h; the conditions for high temperature spray drying in step (4) are: inlet air temperature 200°C, outlet air temperature 80°C, pressure 5 kPa.

[0026] Embodiment 2: A high-yield taurine ammonolysis process, comprising the following steps: 1. Preparation of ammonia complex ion catalyst: Alumina and sodium citrate were mixed, ultrasonically dispersed, stirred for 10 hours, and then ammonia water was added to adjust the pH to 12, and the mixture was sealed and stirred for 10 hours to obtain an ammonia complex ion catalyst; the mass ratio of alumina to sodium citrate was 1:0.6; and the ultrasonic dispersion time was 30 minutes.

[0027] 2. Preparation of taurine: Step (1): mixing an aqueous sodium hydroxyethyl sulfonate solution, ammonia water and an ammonia water complex ion catalyst, stirring them uniformly to obtain a reaction solution; step (2): subjecting the reaction solution obtained in step (1) to a microwave ammonolysis reaction to obtain a sodium aminosulfonate solution; step (3): removing ammonia from the sodium aminosulfonate solution obtained in step (2), adjusting the pH to 8, and obtaining a crude taurine product and a filtrate after crystallization and filtration; step (4): subjecting the filtrate obtained in step (3) to a high-temperature spray drying treatment, and preparing the obtained solid product into an aqueous solution, which is then recycled to step (1) as a mother liquor, and steps (1) to (3) are repeated until the effective components in the mother liquor are completely reacted to obtain taurine. ; In step (1), the mass ratio of sodium hydroxyethyl sulfonate to aqueous ammonia is 1:15; the mass ratio of sodium hydroxyethyl sulfonate to aqueous ammonia complex ion catalyst is 1:0.06; the concentration of aqueous sodium hydroxyethyl sulfonate solution in step (1) is 35%; the concentration of aqueous ammonia is 26%; in step (2), the ammonolysis reaction is carried out under the action of microwaves, and the reaction conditions are: frequency 915 MHZ; time 2 min; temperature 90°C, pressure 1 MPa; in step (3), the temperature for removing ammonia is 165°C; the process conditions for crystallization in step (3) are: temperature 25°C, time 4 h; in step (4), the conditions for high temperature spray drying treatment are: inlet air temperature 220°C, outlet air temperature 90°C, pressure 6 kPa.

[0028] Example 3: A high-yield taurine ammonolysis process comprising the following steps: 1. Preparation of ammonia complex ion catalyst: Alumina and sodium citrate were mixed, ultrasonically dispersed, stirred for 15 hours, and then ammonia water was added to adjust the pH to 12, and the mixture was sealed and stirred for 15 hours to obtain an ammonia complex ion catalyst; the mass ratio of alumina to sodium citrate was 1:0.7; and the ultrasonic dispersion time was 45 minutes.

[0029] 2. Preparation of taurine: Step (1): mixing a sodium hydroxyethyl sulfonate aqueous solution, ammonia water and an ammonia complex ion catalyst, and stirring them uniformly to obtain a reaction solution; step (2): subjecting the reaction solution obtained in step (1) to a microwave ammonolysis reaction to obtain a sodium sulfamate solution; step (3): removing ammonia from the sodium sulfamate solution obtained in step (2), adjusting the pH to 8, and obtaining a crude taurine product and a filtrate after crystallization and filtration; step (4): subjecting the filtrate obtained in step (3) to a high-temperature spray drying treatment, and preparing the obtained solid product into an aqueous solution, which is used as a mother liquor in step (1), and repeating steps (1) to (3) until the effective components in the mother liquor are completely reacted to obtain taurine; The mass ratio of sodium hydroxyethyl sulfonate to aqueous ammonia in step (1) is 1:15; the mass ratio of sodium hydroxyethyl sulfonate to aqueous ammonia complex ion catalyst is 1:0.09; the concentration of the aqueous sodium hydroxyethyl sulfonate solution in step (1) is 45%; the concentration of aqueous ammonia is 27%; the ammonolysis reaction in step (2) is carried out under the action of microwaves, and the reaction conditions are: frequency of 915 MHZ; time of 3 min; temperature of 100° C. and pressure of 2 MPa; the temperature of ammonia removal in step (3) is 175° C.; the process conditions of crystallization in step (3) are: temperature of 35° C. and time of 4 h; the conditions of high temperature spray drying in step (4) are: inlet air temperature of 230° C., outlet air temperature of 100° C. and pressure of 8 kPa.

[0030] Example 4: A high-yield taurine ammonolysis process comprising the following steps: 1. Preparation of ammonia complex ion catalyst: Alumina and sodium citrate were mixed, ultrasonically dispersed, stirred for 24 hours, and then ammonia water was added to adjust the pH to 13, and the mixture was sealed and stirred for 24 hours to obtain an ammonia complex ion catalyst; the mass ratio of alumina to sodium citrate was 1:0.8; and the ultrasonic dispersion time was 60 minutes.

[0031] 2. Preparation of taurine: Step (1): mixing a sodium hydroxyethyl sulfonate aqueous solution, ammonia water and an ammonia complex ion catalyst, stirring them evenly to obtain a reaction solution; step (2): subjecting the reaction solution obtained in step (1) to a microwave ammonolysis reaction to obtain a sodium sulfamate solution; step (3): removing ammonia from the sodium sulfamate solution obtained in step (2), adjusting the pH to 9, and obtaining a crude taurine product and a filtrate after crystallization and filtration; step (4): subjecting the filtrate obtained in step (3) to a high-temperature spray drying treatment, and preparing the obtained solid product into an aqueous solution, which is used as a mother liquor in step (1), and repeating steps (1) to (3) until the effective components in the mother liquor are completely reacted to obtain taurine; The mass ratio of sodium hydroxyethyl sulfonate to aqueous ammonia in step (1) is 1:20; the mass ratio of sodium hydroxyethyl sulfonate to aqueous ammonia complex ion catalyst is 1:0.1; the concentration of the aqueous sodium hydroxyethyl sulfonate solution in step (1) is 50%; the concentration of aqueous ammonia is 28%; the ammonolysis reaction in step (2) is carried out under the action of microwaves, and the reaction conditions are: frequency of 915 MHZ; time of 5 min; temperature of 120° C. and pressure of 3 MPa; the temperature of ammonia removal in step (3) is 185° C.; the process conditions of crystallization in step (3) are: temperature of 40° C. and time of 5 h; the conditions of high temperature spray drying in step (4) are: inlet air temperature of 240° C., outlet air temperature of 120° C. and pressure of 10 kPa.

[0032] Comparative Example 1: Compared with Example 1, no ammonia complex ion catalyst is added to the reaction solution, and other conditions remain unchanged. A high-yield taurine ammonolysis process includes the following steps: Step (1): mixing an aqueous sodium hydroxyethyl sulfonate solution and aqueous ammonia, stirring them evenly to obtain a reaction solution; step (2): subjecting the reaction solution obtained in step (1) to a microwave ammonolysis reaction to obtain a sodium sulfamate solution; step (3): removing ammonia from the sodium sulfamate solution obtained in step (2), adjusting the pH to 7, and obtaining a crude taurine product and a filtrate after crystallization and filtration; step (4): subjecting the filtrate obtained in step (3) to a high-temperature spray drying treatment, and preparing the obtained solid product into an aqueous solution, which is then recycled to step (1) as a mother liquor, and steps (1) to (3) are repeated until the effective components in the mother liquor are completely reacted. The mass ratio of sodium hydroxyethyl sulfonate to ammonia water in step (1) is 1:10; the concentration of the sodium hydroxyethyl sulfonate aqueous solution in step (1) is 30%; the concentration of the ammonia water is 25%; the ammonolysis reaction in step (2) is carried out under the action of microwaves, and the reaction conditions are: frequency 915 MHZ; time 0.5 min; temperature 80°C, pressure 0.2 MPa; the temperature for removing ammonia in step (3) is 155°C; the process conditions for crystallization in step (3) are: temperature 20°C, time 3 h; the conditions for high temperature spray drying in step (4) are: inlet air temperature 200°C, outlet air temperature 80°C, pressure 5 kPa.

[0033] Comparative Example 2: Using Example 1 as a comparison, the mother liquor is not recycled, and other conditions remain unchanged. A high-yield taurine ammonolysis process comprises the following steps: 1. Preparation of ammonia complex ion catalyst: Alumina and sodium citrate were mixed, ultrasonically dispersed, stirred for 6 hours, and then ammonia water was added to adjust the pH to 11, and the mixture was sealed and stirred for 6 hours to obtain an ammonia complex ion catalyst; the mass ratio of alumina to sodium citrate was 1:0.5; and the ultrasonic dispersion time was 10 minutes.

[0034] 2. Preparation of taurine: Step (1): mixing an aqueous sodium hydroxyethyl sulfonate solution, aqueous ammonia and an ammonia complex ion catalyst, stirring them uniformly to obtain a reaction solution; step (2): subjecting the reaction solution obtained in step (1) to a microwave ammonolysis reaction to obtain a sodium aminosulfonate solution; step (3): removing ammonia from the sodium aminosulfonate solution obtained in step (2), adjusting the pH to 7, and filtering the solution to obtain a crude taurine product and a filtrate; step (4): subjecting the filtrate obtained in step (3) to a high-temperature spray drying treatment to remove most of the by-products to obtain taurine; in step (1), the mass ratio of sodium hydroxyethyl sulfonate to aqueous ammonia is 1:10; The mass ratio of sodium ethyl sulfonate to ammonia complex ion catalyst is 1:0.05; the concentration of sodium ethyl sulfonate aqueous solution in step (1) is 30%; the concentration of ammonia water is 25%; the ammonolysis reaction in step (2) is carried out under the action of microwaves, and the reaction conditions are: frequency of 915 MHZ; time of 0.5 min; temperature of 80° C., and pressure of 0.2 MPa; the temperature of ammonia removal in step (3) is 155° C.; the process conditions of crystallization in step (3) are: temperature of 20° C., time of 3 h; the conditions of high temperature spray drying treatment in step (4) are: inlet air temperature of 200° C., outlet air temperature of 80° C., and pressure of 5 kPa.

[0035] Comparative Example 3: Using Example 1 as a comparison, the microwave ammonolysis process is replaced by a common ammonolysis process, and the other conditions remain unchanged. A high-yield taurine ammonolysis process comprises the following steps: 1. Preparation of ammonia complex ion catalyst: Alumina and sodium citrate were mixed, ultrasonically dispersed, stirred for 6 hours, and then ammonia water was added to adjust the pH to 11, and the mixture was sealed and stirred for 6 hours to obtain an ammonia complex ion catalyst; the mass ratio of alumina to sodium citrate was 1:0.5; and the ultrasonic dispersion time was 10 minutes.

[0036] 2. Preparation of taurine: Step (1): mixing an aqueous sodium hydroxyethyl sulfonate solution, aqueous ammonia and an ammonia complex ion catalyst, stirring them uniformly to obtain a reaction solution; Step (2): subjecting the reaction solution obtained in step (1) to an ammonolysis reaction to obtain a sodium aminosulfonate solution; Step (3): removing ammonia from the sodium aminosulfonate solution obtained in step (2), adjusting the pH to 7, and filtering the solution to obtain a crude taurine product and a filtrate; Step (4): subjecting the filtrate obtained in step (3) to a high-temperature spray drying treatment to remove most of the by-products to obtain taurine; the mass fraction of the sodium hydroxyethyl sulfonate and aqueous ammonia in step (1) is 1000 wt %. The mass ratio of sodium hydroxyethyl sulfonate to ammonia complex ion catalyst is 1:10; the mass ratio of sodium hydroxyethyl sulfonate to ammonia complex ion catalyst is 1:0.05; the concentration of sodium hydroxyethyl sulfonate aqueous solution in step (1) is 30%; the concentration of ammonia water is 25%; the process conditions of the ammonolysis reaction in step (2) are: temperature 200°C, pressure 10MPa, time 0.5h; the temperature of ammonia removal in step (3) is 155°C; the process conditions of crystallization in step (3) are: temperature 20°C, time 3h; the conditions of high temperature spray drying treatment in step (4) are: inlet air temperature 200°C, outlet air temperature 80°C, pressure 5kPa.

[0037] Comparative Example 4: Taking Example 1 as a comparison, no ammonia complex ion catalyst is added to the reaction solution, the mother liquor is not recycled, and the microwave ammonolysis process is replaced by a common ammonolysis process, while other conditions remain unchanged to obtain taurine.

[0038] Experiment: Take the taurine obtained in Examples 1-4 and Comparative Examples 1-4, calculate its yield, and detect the residual amount of by-products in the waste liquid; The following table shows the yield of taurine and the residual amount of by-products;

[0039] According to the data in the above table, we can draw the following conclusions: The taurine obtained in Examples 1-4 was compared with the taurine obtained in Comparative Examples 1-4. The test results show that: Compared with Example 1, in Comparative Example 1, no ammonia complex ion catalyst was added to the reaction solution, and the yield of taurine decreased and the residual amount of by-products increased. The reason is that the complex ion catalyst formed by aluminum oxide and ammonia has a large surface area, which can provide more active sites and increase the contact opportunities between reactants and catalysts, thereby improving the efficiency of ammonolysis. Compared with Example 1, in Comparative Example 2, the mother liquor was not recycled, the yield of taurine decreased, and the residual amount of by-products increased; Compared with Example 1, in Comparative Example 3, the microwave ammonolysis process is replaced by the common ammonolysis process, and the yield of taurine decreases significantly, and the residual amount of by-products increases. The reason is that in the reaction system of sodium isethionate and ammonia, the raw materials used are all polar substances, and their dielectric constants and dipoles are relatively large, and the reaction system exists in an ionic state, which has a strong ability to absorb and conduct microwaves; microwaves activate ammonia, hydroxyl groups, and water in the reaction solution, accelerating the reaction; when sodium isethionate reacts with ammonia to generate sodium taurine, microwaves make the reaction easily affected by bond angles and steric hindrance, thereby greatly reducing the generation of by-products; Compared with Example 1, in Comparative Example 4, no ammonia complex ion catalyst was added to the reaction solution, the mother liquor was not recycled, and the microwave ammonolysis process was replaced by a common ammonolysis process. The yield of taurine was greatly reduced, and the residual amount of by-products was greatly increased. It can be seen that the configuration of the process and the materials used in the present application can promote the increase of the yield of the produced taurine and reduce the residual amount of its by-products.

[0040] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be considered exemplary and non-restrictive in all respects, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention.

Claims

1. A high-yield taurine ammonolysis process, characterized in that: The following steps are involved: Step (1): mixing an aqueous sodium hydroxyethyl sulfonate solution, aqueous ammonia and an aqueous ammonia complex ion catalyst, and stirring the mixture to obtain a reaction solution; Step (2): subjecting the reaction solution obtained in step (1) to an ammonolysis reaction to obtain a sodium sulfamate solution; Step (3): removing ammonia from the sodium aminosulfate solution obtained in step (2), adjusting the pH to 7-9, crystallizing, and filtering to obtain a crude taurine product and a filtrate; Step (4): The filtrate obtained in step (3) is subjected to high-temperature spray drying to remove by-products, and the obtained solid product is prepared into an aqueous solution and reused as the mother liquor in step (1). Steps (1) to (3) are repeated until the effective ingredients in the mother liquor are completely reacted to obtain taurine.

2. The high-yield taurine ammonolysis process according to claim 1, characterized in that: The aminolysis reaction in step (2) is carried out under the action of microwaves, and the reaction conditions are: frequency 915 MHZ; time 0.5-5 min; temperature 80-120° C., pressure 0.2-3 MPa.

3. The high-yield taurine ammonolysis process according to claim 1, characterized in that: In step (1), the mass ratio of sodium hydroxyethyl sulfonate to aqueous ammonia is 1:(10-20); The mass ratio of sodium hydroxyethyl sulfonate to ammonia complex ion catalyst is 1:(0.05-0.1).

4. The high-yield taurine ammonolysis process according to claim 1, characterized in that: The concentration of the sodium isethionate aqueous solution is 30-50%; The concentration of the ammonia water is 25-28%.

5. The high-yield taurine ammonolysis process according to claim 1, characterized in that: In step (3), the temperature for removing ammonia is 155-185°C.

6. The high-yield taurine ammonolysis process according to claim 1, characterized in that: The crystallization process conditions in step (3) are: temperature 20-40°C, time 3-5h.

7. The high-yield taurine ammonolysis process according to claim 1, characterized in that: The conditions for high temperature spray drying in step (4) are: inlet air temperature 200-240°C, outlet air temperature 80-120°C, and pressure 5-10 kPa.

8. The high-yield taurine ammonolysis process according to claim 1, characterized in that: The ammonia complex ion catalyst is prepared by the following process: Alumina and sodium citrate are mixed, ultrasonically dispersed, stirred for 6-24 hours, and then ammonia water is added to adjust the pH to 11-13, and the mixture is sealed and stirred for 6-24 hours to obtain an ammonia water complex ion catalyst.

9. The high-yield taurine ammonolysis process according to claim 8, characterized in that: The mass ratio of aluminum oxide to sodium citrate is 1:(0.5-0.8).

10. The high-yield taurine ammonolysis process according to claim 1, characterized in that: The ultrasonic dispersion time is 10-60 min.

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