Green production process of zinc glycinate

Abstract

The invention discloses a green production process of zinc glycinate, which comprises the following steps: adding deionized water into a reaction kettle, heating, adding glycine for dissolving, adding zinc hydroxide or zinc oxide after dissolving, reacting at 80-95 DEG C, keeping the temperature for 15-25 minutes, after the reaction is finished, filtering out unreacted zinc oxide, adding into the reaction kettle again, cooling and crystallizing the filtered mother liquor, and filtering to obtain the zinc glycinate. And centrifugally separating to obtain a wet product and separated mother liquor, completely circulating the separated mother liquor, re-putting the separated mother liquor into the reaction kettle, and drying, screening and packaging the wet zinc glycinate product to obtain a finished product. According to the production process, no additional antioxidant needs to be introduced, the prepared zinc glycinate is high in purity, energy is saved, environment friendliness is achieved, and continuous industrial green production is achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of zinc glycinate production, in particular to a green production process of zinc glycinate. BACKGROUND

[0002] Zinc glycinate is a compound formed by the chelation of zinc ions and the amino acid glycine. Due to its unique chemical structure and biological properties, it has significant advantages in the fields of nutrition supplementation, medical treatment, and agriculture. Zinc glycinate can promote the growth and development of children, enhance immunity, and improve taste and appetite, making it the best supplement for zinc deficiency symptoms.

[0003] Currently, zinc glycinate is obtained through a one-step reaction of glycine and zinc compounds. There are many synthesis methods, among which the synthesis method of glycine and zinc oxide aqueous solution has become the mainstream process. Patent document CN120136715A discloses a preparation method of zinc glycinate chelate. Glycine and nano-zinc oxide are pre-mixed and then added to water. The mixture is treated under microwave and ultrasonic assistance. Glycine suspension is prepared. After adding L-ascorbic acid, stirring is performed. Then, the temperature is maintained at 58-62℃ for 30-40min, and then the temperature is increased to 74-80℃ for 2-3h. Then, the temperature is decreased to room temperature. After standing, centrifugal separation is performed. After drying, zinc glycinate chelate is obtained. This production process uses microwave and ultrasonic assistance to improve the coordination efficiency, which consumes a lot of energy. In addition, L-ascorbic acid is introduced into the reaction system. After the reaction synthesis, the mother liquor contains a large amount of organic matter, which is difficult to handle.

[0004] Patent document CN118530131A discloses a preparation and application of high-purity medical-grade zinc glycinate. First, a suitable amount of pure water is added to the reactor and heated to 80-90℃. Then, excess glycine is slowly added under stirring to obtain a reaction solution. The chelation reaction is continued for 1.5h. The reaction solution is filtered while hot and placed in a crystallization container. The temperature is cooled to below 30℃ for crystallization. The crystallized zinc glycinate is separated from the mother liquor by suction filtration. The mother liquor is recycled. The pure zinc glycinate crystals are dried at 80℃, and then crushed and sieved to obtain high-purity medical-grade zinc glycinate. The raw material used in the preparation process is analytical pure zinc oxide. In the factory scale-up test, the impurity content of the raw material is high. The recycling of the mother liquor improves the utilization rate, but also further increases the impurity content in the reaction system, which seriously reduces the purity of the final product. The purity of the factory production is difficult to guarantee.

[0005] How to realize the high-purity and large-scale green production of zinc glycinate is the research focus of enterprises. SUMMARY

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide a green production process for zinc glycinate, so as to solve the problems of high energy consumption, pollution and low purity in the industrial production of zinc glycinate in the prior art.

[0007] The objective of this invention is achieved through the following technical solution: a green production process for zinc glycinate, comprising the following steps,

[0008] S1. Add deionized water to the reaction vessel, heat it, and add glycine to dissolve it;

[0009] S2. After dissolving, add zinc oxide and react at 80-95℃ for 15-25 minutes.

[0010] S3. After the reaction is complete, filter out the unreacted zinc hydroxide or zinc oxide and put it back into the reaction vessel. Cool the filtered mother liquor to crystallize, and centrifuge to obtain the wet product and the separated mother liquor.

[0011] S4. The entire mother liquor is recycled back into the reactor. The wet zinc glycinate is dried, sieved, and packaged to obtain the finished product.

[0012] Preferably, the process also includes step S5, where the centrifuged mother liquor is recycled to a specified number of times, then concentrated and crystallized under reduced pressure, the wet product is separated by centrifugation and put back into the reaction vessel, and the concentrated mother liquor is treated as wastewater.

[0013] Preferably, the centrifuged mother liquor is recycled 10 times.

[0014] Preferably, the unqualified products after sieving are put into the centrifugal mother liquor for vacuum concentration and crystallization.

[0015] Preferably, the molar ratio of glycine to zinc hydroxide or zinc oxide in the reaction system is 2:1, and the mass ratio of glycine to deionized water is 1:2.

[0016] Preferably, the vacuum degree of the vacuum concentration is -0.05 MPa, and the vacuum concentration temperature is 85°C.

[0017] Preferably, the wet zinc glycinate is dried at 95°C for 1.5 hours.

[0018] The present invention has the following advantages:

[0019] 1. This invention uses the cooling crystallization method in aqueous solution synthesis to achieve the industrial production of zinc glycine chelate. The production process does not introduce antioxidants such as iron powder and ascorbic acid, and no additional processing steps are required, making it more energy-efficient and environmentally friendly.

[0020] 2. Compared with other processes, the production process of this invention shortens the reaction synthesis time, recycles the mother liquor multiple times, ensures continuous large-scale production capacity, improves raw material utilization, and reduces the impurity content introduced into the reaction system during the mother liquor recycling process by concentrating and reprocessing the mother liquor after multiple cycles. This achieves a high purity of 99% for zinc glycine, ensuring the purity of industrial production and avoiding the impact of high impurity content and fluctuations in impurity content on product purity. Attached Figure Description

[0021] Figure 1 This is a simplified process flow diagram of the present invention. Detailed Implementation

[0022] The present invention will be further described in detail below with reference to the embodiments.

[0023] The reaction equation for the synthesis of zinc glycine dihydrate from zinc oxide is as follows:

[0024] ZnO+2NH2CH2COOH→Zn(NH2CH2COO)2+H2O

[0025] A green production process for 1800 tons of zinc glycine per year, such as... Figure 1 As shown, it includes the following steps:

[0026] S1. Add 4 tons of deionized water to the reactor, heat it up and add 2 tons of glycine to dissolve it;

[0027] S2. After dissolving, add zinc oxide and react at 80-95℃ for 15-25 min. The initial molar ratio of glycine to zinc hydroxide or zinc oxide in the reaction system is 2:1, and the mass ratio of glycine to deionized water is 1:2.

[0028] S3. After the reaction is complete, filter out the unreacted zinc oxide and put it back into the reactor. Cool the filtered mother liquor to 25°C to crystallize, and centrifuge to obtain the wet product and the separated mother liquor.

[0029] S4. The mother liquor is completely recycled back into the reactor. The wet zinc glycinate is dried at 95℃ for 1.5 hours, sieved, and packaged to obtain the finished product.

[0030] S5. After the centrifuged mother liquor is recycled up to 10 times, it is concentrated and crystallized under reduced pressure. The vacuum degree of the reduced pressure concentration is -0.05 MPa and the temperature of the reduced pressure concentration is 85°C. The wet product is separated by centrifugation and put back into the reaction vessel. The concentrated mother liquor is treated as wastewater.

[0031] The material balance table for the entire process of producing 1800 t / a of zinc glycinate is shown below.

[0032]

[0033] Although the present application has been described in detail with reference to the foregoing embodiments, the technical solutions recorded in the foregoing embodiments can be modified, or some of the technical features can be replaced by equivalent features, by those skilled in the art, any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A green production process for zinc glycinate, characterized in that: Includes the following steps, S1. Add deionized water to the reaction vessel, heat it, and add glycine to dissolve it; S2. After dissolving, add zinc hydroxide or zinc oxide, and react at 80-95℃ for 15-25 minutes. S3. After the reaction is complete, filter out the unreacted zinc oxide and put it back into the reactor. Cool the filtered mother liquor to crystallize, and centrifuge to obtain the wet product and the separated mother liquor. S4. The entire mother liquor is recycled back into the reactor. The wet zinc glycinate is dried, sieved, and packaged to obtain the finished product.

2. The green production process for zinc glycinate according to claim 1, characterized in that: It also includes step S5, in which the centrifuged mother liquor is recycled to a specified number of times, then concentrated and crystallized under reduced pressure, the wet product is separated by centrifugation and put back into the reaction vessel, and the concentrated mother liquor is treated as wastewater.

3. The green production process for zinc glycinate according to claim 2, characterized in that: The centrifuged mother liquor is recycled 10 times.

4. The green production process for zinc glycinate according to claim 2, characterized in that: The unqualified products after sieving are put into the centrifugal mother liquor for vacuum concentration and crystallization.

5. The green production process for zinc glycinate according to claim 1, characterized in that: The molar ratio of glycine to zinc oxide in the reaction system is 2:1, and the mass ratio of glycine to deionized water is 1:

2.

6. The green production process for zinc glycinate according to claim 2, characterized in that: The vacuum degree of the vacuum concentration is -0.05 MPa, and the vacuum concentration temperature is 85°C.

7. The green production process for zinc glycinate according to claim 1, characterized in that: The wet glycine zinc product was dried at 95°C for 1.5 hours.

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