Preparation and application of rosinyl trihydroxamic acid (salt)

Abstract

The invention belongs to the field of preparation of organic compounds, and particularly relates to a preparation method and application of rosin-based ternary hydroxamic acid (salt). The preparation method comprises the steps that under the stirring condition, a hydroxylamine solution serves as a substrate, rosin-based ternary acyl chloride or ester is added, the ternary hydroxamic acid compound is synthesized, and the molar ratio of acyl chloride (or ester) to hydroxylamine is 1: 4.5-8. The preparation method comprises the following steps: carrying out D-A addition on natural renewable rosin serving as an initial raw material and unsaturated dibasic acid to obtain tribasic acid, and reacting the activated tribasic acid with a hydroxylamine solution to obtain the rosin-based ternary hydroxamic acid (salt). The synthesized product has a plurality of hydroximic acid groups, has strong coordination ability with metal ores and metal ions, can be used for removing toxic heavy metal cations in environmental water, can also be used for recovering precious metal or rare metal ions in water, and can also be used as a flotation collector for metal ores.

Description

Technical Field

[0001] The invention belongs to the field of organic compound preparation, and in particular relates to a method for preparing ternary hydroxamic acid or hydroxamate. Background Art

[0002] Hydroxamic acid has two tautomers, hydroxamic acid (isohydroxamic acid) and hydroxamic acid. These two isomers exist at the same time, but isohydroxamic acid is the main one, and its general structural formula is RC(OH)=NOH. This structure has oxygen atoms and nitrogen atoms that are close to each other, and these two atoms have lone electron pairs. Due to its efficient chelation, it has a wide range of applications in flotation, metallurgy and medicine. In flotation and metallurgy, hydroxamic acid can chelate with metal ions (Sn2+, Pb2+, Cu2+, Co2+, Ni2+, Cd2+, etc.) on the surface of minerals and in industrial wastewater to form a stable polycyclic metal chelate, so that hydroxamic acid and its hydroxamate compounds are widely used in the fields of flotation of metal minerals, wastewater treatment, etc. In medicine, hydroxamic acid is used in combination with other drugs or protein deacetylase inhibitors to have a wide range of pharmacological effects in treating cancer, cardiovascular disease, HIV, Alzheimer's disease, malaria, and allergic diseases.

[0003] Traditional hydroxamic acid usually has only one hydroxamic acid functional group. The preparation method generally uses hydroxylamine salt and organic acid ester to react in an alkaline solvent. The commonly used solvent is water or methanol. For example, patent CN101519365A discloses a production method of salicylic hydroxamic acid, which uses a strong alkaline aqueous solution to maintain the pH value of the reaction system at about 12.0, and after mixing the measured hydroxylamine aqueous solution and methyl salicylate for a certain period of time, the pH is adjusted to 4.0-5.0 with an acid to obtain salicylic hydroxamic acid; patent CN102513218A discloses a preparation method of a collector for bauxite flotation, which uses hydroxylamine sulfate to react with methyl salicylate. Aqueous amine solution, methyl benzoate and caustic soda solution react in a certain proportion to obtain a hydroxamate product; there are very few products with two or more hydroxamic acid functional groups. For example, Sun Xin et al. prepared phthalic dihydroxamic acid (Synthesis of a new hydroxamic acid collector and its collection mechanism for malachite [J]. Mineral Conservation and Utilization, 2022, 42(1): 9), which is to react dimethyl phthalate, hydroxylamine hydrochloride and sodium hydroxide in a three-necked flask at a molar ratio of 1:2.1:8.4 at 50°C for 4 hours, and then acidify with hydrochloric acid to a pH of 4-5 to obtain phthalic dihydroxamic acid with a dihydroxamic acid group.

[0004] The commonly used hydroxamic acids such as benzohydroxamic acid and salicylic hydroxamic acid currently used in industrial applications have the following problems: ① The raw materials for the preparation of hydroxamic acid compounds mostly come from petrochemical derivatives such as styrene, which is not conducive to green environmental protection and sustainable development; ② Most of the existing isohydroxamic acid molecules have only one hydroxamic acid functional group, which can only chelate with one metal ion, and the low efficiency leads to excessive use of hydroxamic acid, which in turn increases the cost of use in actual production. In order to solve these existing problems, research work is planned to be carried out from the following aspects: ① Use renewable resources as hydroxamic acid raw materials instead of petrochemical derivative raw materials; ② Increase the number of chelating functional groups in hydroxamic acid molecules, improve the adsorption and collection efficiency of hydroxamic acid, and reduce the amount of hydroxamic acid used in production and thus reduce production costs.

[0005] According to the results of literature research, there has been no research report on the use of renewable resource rosin to replace petrochemical products to prepare polyhydroxames. As my country pays more and more attention to environmental issues, the preparation and application of rosin-based trihydroxamic acid (salt) of the present invention are of great significance to the research and development of efficient and environmentally friendly hydroxamic acid and hydroxamic acid salt compounds and the optimization of their preparation process. Summary of the invention

[0006] The present invention mainly provides a rosin-based tribasic hydroxamic acid (salt) and its preparation method and application. Renewable rosin is used as a starting material, and DA addition is carried out with an unsaturated dibasic acid to obtain a tribasic acid. The activated tribasic acid reacts with a hydroxylamine solution to obtain a rosin-based tribasic hydroxamic acid (salt). The synthesized product has multiple hydroxamic acid groups and has a strong coordination ability with metal ores and metal ions. It can be used to remove toxic heavy metal cations in environmental water bodies, and can also be used to recover precious metals or rare metal ions in water, and can also be used as a flotation collector for metal ores. The technical scheme is as follows:

[0007] A method for preparing a tribasic hydroxamic acid comprises the following steps: using a hydroxylamine solution as a substrate, adding rosin trichloride or rosin triester under stirring conditions, and synthesizing rosin trihydroxamic acid (salt) compounds, wherein the molar ratio of rosin trichloride (or ester) to hydroxylamine is 1:4.5-8.

[0008] Preferably, the preparation method comprises the following steps:

[0009] (1) The hydroxylamine solution is prepared from hydroxylamine salt, base and solvent. The hydroxylamine salt, base and solvent in the formula are stirred at 5-35° C. for 0.5-1 h to obtain a hydroxylamine solution.

[0010] (2) The acid chloride is rosin-based triacyl chloride, and the ester is rosin-based triacid ester, and the precursor of both, fumaric rosin, is derived from the modification of rosin, a renewable biomass resource. The solution preparation method comprises taking the formulated amount of acid chloride (or ester) and solvent to prepare an acid chloride (or ester) solution.

[0011] (3) Add the acyl chloride (ester) solution dropwise to the hydroxylamine solution while stirring it at a temperature of -5°C to 95°C, and keep the temperature to react for 2-6 hours; then separate and purify to obtain a hydroxamic acid solution.

[0012] The preparation method of the rosin-based trihydroxamate is as follows: preferably, an alkaline ethanol solution is added to a hydroxamic acid solution, and the solution is centrifuged and dried to obtain the hydroxamate.

[0013] Preferably, in step (1), the hydroxylamine salt is hydroxylamine hydrochloride or hydroxylamine sulfate, and the base is one or two of sodium hydroxide, potassium hydroxide, sodium bicarbonate, sodium carbonate, triethylamine, and pyridine; and the molar ratio of the base to the hydroxylamine salt is 1:1-2.

[0014] Preferably, the concentration of the acyl chloride solution in step (2) is 5%-15%. The concentration of the ester solution is 10%-20%,

[0015] Preferably, the alkaline ethanol solution in the preparation of rosin-based trihydroxamate is one or more of sodium hydroxide, potassium hydroxide, sodium bicarbonate and sodium carbonate.

[0016] Preferably, when used to treat wastewater containing metal ions, a formulated amount of rosin-based trihydroxamic acid is taken, and the sodium salt or its sodium salt is prepared into an aqueous solution and added to the wastewater. The metal ions form a complex with it to produce precipitation, and direct and simple filtration can achieve the purpose of recovering precious metal ions in the wastewater or removing toxic metal ions in the water.

[0017] By adopting the above scheme, the present invention has the following advantages:

[0018] The invention uses renewable rosin as a starting material, performs diene addition reaction with an unsaturated dibasic acid to obtain a tribasic acid, and reacts the activated tribasic acid with a hydroxylamine solution to obtain a rosin-based tribasic isohydroxamic acid (salt). The synthesized product has multiple hydroxamic acid groups, has a strong coordination ability with metal ores and metal ions, can be used to remove toxic heavy metal cations in environmental water bodies, can also be used to recover precious metals or rare metal ions in water, and can also be used as a flotation collector for metal ores, has simple and convenient post-processing, and is environmentally friendly. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 IR spectra of rosin-based tribasic acid and rosin-based trihydroxamic acid prepared in Example 1 of the present invention.

[0020] Figure 2 This is an infrared spectra of rosin-based trihydroxamic acid and rosin-based trihydroxamic acid sodium salt prepared in Example 1 of the present invention.

[0021] Figure 3This is the infrared spectrum of the rosin-based trihydroxamic acid sodium salt after adsorbing metal ions in Examples 3, 4, 5, and 6 of the present invention. DETAILED DESCRIPTION

[0022] The present invention is further illustrated by the following examples. Unless otherwise specified, all of them are conventional methods, and the experimental reagents and materials involved are conventional biochemical reagents and materials unless otherwise specified.

[0023] Example 1

[0024] In this embodiment, hydroxylamine hydrochloride is used as a raw material to react with rosin triacyl chloride to prepare rosin trihydroxamic acid and its sodium salt. The specific synthesis process is as follows:

[0025] 3.00g of triethylamine, 2.60g of hydroxylamine hydrochloride and dichloromethane were stirred at 25°C for 1h to obtain a hydroxylamine solution as a reaction substrate; 2.00g of rosin-based triacyl chloride and a certain amount of dichloromethane were prepared into a 10% acyl chloride solution; at 5°C, the hydroxylamine solution was stirred while the acyl chloride solution was added dropwise, and the temperature was kept for 2h after the addition was completed; the reaction product was filtered to obtain a rosin-based trihydroxamic acid solution, and after drying, a rosin-based trihydroxamic acid solid was obtained, and its infrared spectrum showed Figure 1 ; Add sodium hydroxide ethanol solution to the rosin-based trihydroxamic acid solution, centrifuge and dry to obtain rosin-based trihydroxamic acid sodium salt, the infrared spectrum of which is shown in Figure 2 .

[0026] Example 2

[0027] In this embodiment, hydroxylamine hydrochloride is used as a raw material to prepare rosin-based triisohydroxamic acid and its sodium salt with rosin-based triacid esters. The specific synthesis process is as follows:

[0028] Take 2.42g of sodium hydroxide, 1.21g of hydroxylamine hydrochloride and water and stir for 1h at 25℃ to obtain the reaction substrate hydroxylamine solution; take 2.00g of rosin-based triacid ester and a certain amount of ethyl acetate to prepare a 10% ester solution; add the hydroxylamine solution and the ester solution into a three-necked flask and react at 45℃ for 4h; filter the reaction product to obtain rosin-based trihydroxamic acid solution; add sodium hydroxide aqueous solution to the rosin-based trihydroxamic acid solution, centrifuge and dry to obtain rosin-based trihydroxamic acid sodium salt. .

[0029] Example 3

[0030] This embodiment uses the synthesized sodium salt of rosin-based triisohydroxamic acid as raw material to treat the simulated industrial wastewater containing Cu2+ ions with an initial Cu2+ concentration of 20 mg / L and a pH of 5.0. The specific process is as follows:

[0031] Prepare 25mL of standard solution with an initial concentration of Cu2+ of 20mg / L and pH=5.0, add 25mg of sodium rosin trihydroxamic acid, and statically adsorb at 25℃ for 24h; 96.06% of the Cu2+ ions in the simulated industrial wastewater are adsorbed and recovered by sodium rosin trihydroxamic acid, and the performance is good. After simple filtration, the chelate of Cu2+ ions and sodium rosin trihydroxamic acid is obtained, and its infrared spectrum shows Figure 3 .

[0032] Example 4

[0033] This embodiment uses the synthesized sodium salt of rosin-based trihydroxamic acid as raw material to treat simulated Cd2+ ion-containing wastewater with an initial Cd2+ concentration of 20 mg / L and a pH of 5.0. The specific process is as follows:

[0034] Prepare 25mL of a standard solution with an initial concentration of 20mg / L of Cd2+ and a pH of 5.0, add 25mg of sodium rosin trihydroxamic acid, and perform static adsorption at 25℃ for 24h; 97.23% of the Cd2+ ions in the simulated industrial wastewater are removed by sodium rosin trihydroxamic acid, and the performance is good. After simple filtration, the chelate of Cd2+ ions and rosin trihydroxamic acid is obtained, and its infrared spectrum shows Figure 3 .

[0035] Example 5

[0036] This embodiment uses the synthesized sodium salt of rosin-based triisohydroxamic acid as the raw material to treat the simulated Fe2+ ion-containing wastewater with an initial Fe2+ concentration of 20 mg / L and a pH of 5.0. The specific process is as follows:

[0037] Prepare 25mL standard solution with an initial Fe2+ concentration of 20mg / L and pH=5.0, add 25mg of rosin-based trihydroxamic acid sodium salt, and statically adsorb at 25℃ for 24h; the removal rate of Fe2+ by rosin-based trihydroxamic acid sodium salt reaches 97.28%, and the performance is good. After simple filtration, the chelate of Fe2+ ions and rosin-based trihydroxamic acid is obtained, and its infrared spectrum shows Figure 3 .

[0038] Example 6

[0039] This embodiment uses the synthesized sodium salt of rosin-based triisohydroxamic acid as raw material to treat simulated sewage with an initial Ni2+ concentration of 40 mg / L and a pH of 5.0. The specific process is as follows:

[0040] Prepare 25mL of standard solution with an initial Ni2+ concentration of 40mg / L and pH=5.0, add 25mg of sodium rosin trihydroxamic acid salt, and statically adsorb at 25℃ for 24h; the removal rate of sodium rosin trihydroxamic acid salt on Ni2+ reaches 69.26%. After simple filtration, the chelate of Ni2+ ion and rosin trihydroxamic acid is obtained, and its infrared spectrum shows Figure 3 .

Claims

1. A rosin-based trihydroxamic acid, characterized in that The structure contains rosin phenanthrene ring structure and has corresponding tautomers. The molecular formula is 2. The method for preparing rosin-based trihydroxamic acid according to claim 1, characterized in that: Under stirring conditions, hydroxylamine solution is used as a substrate, rosin trichloride or rosin triester is added to synthesize rosin triisohydroxamic acid (salt) compounds, wherein the molar ratio of rosin trichloride (or ester) to hydroxylamine is 1:4.5-8.

3. The rosin-based trihydroxamic acid according to claim 1, wherein the preparation method thereof is characterized in that the hydroxylamine solution is prepared from a hydroxylamine salt, a base and a solvent.

4. The rosin-based trihydroxamic acid according to claim 1, wherein the acyl chloride described in 2 is rosin-based triacyl chloride, the ester is rosin-based triacid ester, and the precursors of the two are fumaric rosin derived from the modification of rosin from renewable biomass resources. Specifically, fumaric rosin is prepared by reacting rosin and fumaric acid through diene synthesis, and then rosin-based triacyl chloride or rosin-based triacid ester is obtained through chlorination or esterification, and then directly used to prepare rosin-based trihydroxamic acid.

5. The method for preparing rosin-based trihydroxamic acid according to claim 1, characterized in that: The specific preparation method comprises the following steps: (1) taking the formulated amount of hydroxylamine salt, base, and solvent and stirring at 5-35° C. for 0.5-1 h to obtain a hydroxylamine solution; (2) taking a prescribed amount of acyl chloride (or ester) and a solvent to prepare an acyl chloride (or ester) solution; (3) Add the acyl chloride (ester) solution dropwise to the hydroxylamine solution while stirring it at a temperature of -5°C to 95°C, and keep the temperature to react for 2-6 hours; then separate and purify to obtain a hydroxamic acid solution.

6. The rosin-based trihydroxamic acid according to claim 1, wherein the preparation method of the rosin-based trihydroxamic acid salt thereof is as follows: adding an alkaline ethanol solution to the hydroxamic acid solution prepared in 5, centrifuging and drying to obtain the hydroxamic acid salt.

7. The preparation method according to claim 5, characterized in that: In the preparation method step (1), the hydroxylamine salt is hydroxylamine hydrochloride or hydroxylamine sulfate, the base is one or two of sodium hydroxide, potassium hydroxide, sodium bicarbonate, sodium carbonate, triethylamine, and pyridine; the solvent is water, dichloromethane or ethyl acetate, and the molar ratio of the base to the hydroxylamine salt is 1:1-2.

8. The preparation method according to claim 5, characterized in that: The solvent in step (2) of the preparation method is one or more of dichloromethane, ethyl acetate and tetrahydrofuran, the concentration of the acyl chloride solution is 5%-15%, and the concentration of the ester solution is 10%-20%.

9. The method for preparing rosin-based trihydroxamate according to claim 6, characterized in that The alkaline ethanol solution is one or more of sodium hydroxide, potassium hydroxide, sodium bicarbonate and sodium carbonate.

10. A rosin-based trihydroxamic acid according to claim 1, characterized in that When used to treat wastewater containing metal ions, its sodium salt or its sodium salt in aqueous solution is added to the wastewater. The metal ions form a complex with it to produce precipitation. Direct and simple filtration can achieve the purpose of recovering precious metal ions and removing toxic metal ions in the water.

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