阅读说明：本技术 一种谷氨酸螯合剂的制备及应用 (Preparation and application of glutamic acid chelating agent ) 是由 陈洪龄 曹添 吴亚军 于 2020-05-22 设计创作，主要内容包括：本发明提供一种新的谷氨酸螯合剂,具有较高的螯合能力及较好的生物降解性。谷氨酸具有两个羧基,同时又具有活性基团氨基,马来酸酐中碳氧双键可以与谷氨酸钠中的氨基反应,形成氨基多羧酸结构,在结构方面不同于EDTA,其中间连接基团为酰胺基而不是EDTA的烷基胺,酰胺结构具有更好的生物降解性。该谷氨酸螯合剂溶于水后,三个羧基的结构为其提供良好的螯合能力,能更好地结合金属离子,可在日用洗涤、水处理、纺织、造纸、农业、医药等领域有着广泛的应用。(The invention provides a novel glutamic acid chelating agent which has higher chelating capacity and better biodegradability. Glutamic acid has two carboxyl groups and active group amino, carbon-oxygen double bond in maleic anhydride can react with amino in sodium glutamate to form an aminopolycarboxylic acid structure, the aminopolycarboxylic acid structure is different from EDTA in the aspect of structure, the intermediate connecting group is an amido group instead of alkylamine of EDTA, and the amide structure has better biodegradability. After the glutamic acid chelating agent is dissolved in water, the structure of three carboxyl groups provides good chelating capacity for the glutamic acid chelating agent, and the glutamic acid chelating agent can better combine metal ions and can be widely applied to the fields of daily washing, water treatment, spinning, papermaking, agriculture, medicine and the like.)

1. The preparation and application of a glutamic acid chelating agent are characterized in that the chelating agent is generated by the amide bond linking reaction of maleic anhydride and glutamic acid;

the preparation method of the chelating agent comprises the following steps: dissolving a certain amount of maleic anhydride in an organic solvent, fully and uniformly stirring, adding sodium glutamate at a certain temperature, fully reacting to obtain a crude product, and directly using the crude product or washing the crude product with absolute ethyl alcohol after filtering to obtain a high-purity sample.

2. The preparation and use of a glutamic acid sequestering agent according to claim 1, wherein said organic solvent is acetone or 1, 4-dioxane.

3. The preparation and use of a glutamic acid sequestering agent according to claim 1, wherein the molar ratio of maleic anhydride to sodium glutamate is 1-1.1: 1.

4. The preparation and use of a glutamic acid sequestering agent according to claim 1, wherein said reaction temperature is 20 to 55 ℃.

5. The preparation and use of a glutamic acid sequestering agent according to claim 1, wherein said reaction time is 4 to 6 hours.

6. The glutamic acid chelating agent of claim 1, which can be used in combination with other polycarboxylic chelating agents to achieve better chelating effect.

7. The glutamic acid chelating agent of claim 1, which is applicable to detergents, water treatment agents, corrosion inhibitors, electroplating industries, pharmaceutical industries, textile dyeing, catalytic synthesis, extraction and separation.

8. The glutamic acid chelating agent of claim 1, in an amount of 1 to 5% when used.

Technical Field

The invention relates to a glutamic acid chelating agent, and also relates to a preparation method and application of the chelating agent.

Background

The metal atom or ion reacts with a ligand containing two or more coordinating atoms to produce a chelate having a cyclic structure. Such ligand substances capable of forming chelates are called chelating agents. The chelating agent has special stability after being combined with metal ions, and a small amount of the chelating agent is added into a required system, so that the metal ions in the system can be effectively combined, and the concentration of the metal ions is reduced to enable the metal ions to meet the process requirements. The method is widely applied to the fields of daily washing, water treatment, spinning, papermaking, agriculture, medicine and the like.

The chelating agents commonly used are mainly phosphates, hydroxy acids, amino acids and carboxylic acid polymers. Phosphate is mainly Sodium Tripolyphosphate (STPP), but because the discharge of phosphorus causes eutrophication of the environment to form pollution, and related regulations are also provided in various countries to limit the use of phosphorus-containing chemicals, so that phosphate chelating agents are gradually fading out of the market. The hydroxy acid mainly comprises sodium gluconate, sodium citrate, sodium tartrate and the like, is green and environment-friendly, but has a common chelating effect, so that the hydroxy acid is not used in a large amount. The amino acid chelating agent has good chelating effect, the Ethylene Diamine Tetraacetic Acid (EDTA) can complex various metal ions to form a 1:1 compound with the various metal ions, the chelating performance is good, but the biodegradability of the EDTA is questioned and is not environment-friendly. Chelate generated by nitrilotriacetic acid (NTA) is stable and has an advantage in price, but the chelate can be carcinogenic when the concentration is too high; diethylenetriaminepentaacetic acid (DTPA) may be harmful to humans and fetuses.

The chelating agent with good chelating effect, green and environmental protection is more and more emphasized, and the market demand is more and more increased.

The invention provides a novel glutamic acid chelating agent, which has higher chelating ability and better biodegradability, improves the defects of the chelating agent and is a novel green environment-friendly chelating agent. Glutamic acid has two carboxyl groups and active group amino, carbon-oxygen double bond in maleic anhydride can react with amino in sodium glutamate to form an aminopolycarboxylic acid structure, the aminopolycarboxylic acid structure is different from EDTA in the aspect of structure, the intermediate connecting group is an amido group instead of alkylamine of EDTA, and the amide structure has better biodegradability. After the glutamic acid chelating agent is dissolved in water, the structure of three carboxyl groups provides good chelating capacity for the glutamic acid chelating agent, and the glutamic acid chelating agent can better combine metal ions and can be widely applied to the fields of daily washing, water treatment, spinning, papermaking, agriculture, medicine and the like.

Disclosure of Invention

The invention aims to provide a novel glutamic acid chelating agent, and a preparation method and application thereof

In order to achieve the purpose, the invention adopts the following technical scheme:

a glutamic acid sequestering agent having the formula:

the glutamic acid chelating agent is obtained by reacting sodium glutamate with maleic anhydride.

The invention provides a preparation method of the glutamic acid chelating agent

Dissolving a certain amount of maleic anhydride in an organic solvent, and fully and uniformly stirring. At a certain temperature, sodium glutamate is added for full reaction to obtain a crude product which can be directly used, or after filtration, the crude product is washed by absolute ethyl alcohol to obtain a high-purity sample.

The organic solvent is usually acetone or 1, 4-dioxane.

The molar ratio of the maleic anhydride to the sodium glutamate is 1-1.1:1

The reaction temperature is 20-55 deg.C

The reaction time is 4-6h

The glutamic acid chelating agent can be compounded with other polycarboxylic acid chelating agents for use, so that a better effect is achieved.

The glutamic acid chelating agent can be applied to detergents, water treatment agents, corrosion inhibitors, scale inhibitors, electroplating industries, medicine industries, dyeing processes, catalytic synthesis, extraction and separation, and the usage amount is 1-5%.

The invention has the beneficial effects that:

the glutamic acid chelating agent is obtained by reacting sodium glutamate with maleic anhydride, the sodium glutamate is rich in raw materials and is green and environment-friendly, and the chelating agent obtained by reacting the sodium glutamate with the maleic anhydride conforms to the concept and trend of sustainable development. The prepared glutamic acid chelating agent has 2 carboxyl groups and 1 sodium carboxylate group, has stable structure and good water solubility, can be better combined with metal ions, is an environment-friendly chelating agent, and has wide application industry and practical popularization value. The chelating agent prepared by the method has mild conditions, and the subsequent purification and separation process is simple and suitable for large-scale production.

The specific implementation method comprises the following steps:

the following examples are given for the purpose of illustration, and the present invention is not limited to the following examples. The experimental protocol, in which the specific conditions are not specified in the examples, is generally carried out according to the conventional conditions or conditions recommended by the manufacturer.

Examples and comparative examples of glutamic acid chelating agent preparation