Application of benzyltrimethyl eutectic solvent in extraction of amaranth dye

Abstract

The invention discloses application of a benzyltrimethyl eutectic solvent in extraction of amaranth red dye, and belongs to the technical field of eutectic solvents. The method comprises the following steps: putting an ABS (Acrylonitrile Butadiene Styrene) solution formed by a benzyltrimethyl eutectic solvent and K3PO4 into an aqueous solution containing amaranth, and extracting the amaranth dye under a constant-temperature stirring condition. The benzyltrimethyl eutectic solvent is synthesized from benzyltrimethyl ammonium chloride and triethylene glycol. An ABS (Acrylonitrile Butadiene Styrene) solution formed by the benzyltrimethyl deep-eutectic solvent prepared by the invention and K3PO4 has relatively strong trapping capacity on amaranth dye, and the extraction efficiency of the amaranth dye is up to 98.1% under the condition that the mass ratio of the ABS solution to an aqueous solution containing amaranth is 1: 1. Meanwhile, the benzyltrimethyl eutectic solvent has the advantages of simple synthesis, low price and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of low eutectic solvents, and particularly relates to application of a benzyltrimethylol low eutectic solvent in extracting amaranth dye. Background Art

[0002] The textile industry uses about 10,000 tons of synthetic dyes every year. These synthetic dyes are toxic and their discharge into the aquatic environment as wastewater can lead to the release of polluted effluents containing high concentrations of pollutants. The molecular structure of these toxic dyes is very stable, which makes them difficult to degrade in water treatment plants. Most of the dyes used in the textile industry are azo type (N=N), such as amaranth (RA), which are characterized by water solubility, good stability, and resistance to chemical reagent reactions. Therefore, exploring effective extractants is crucial to achieve rapid and efficient capture and stable storage of amaranth dyes.

[0003] Deep eutectic solvents are a type of "quasi-ionic liquid" composed of hydrogen bond acceptors and hydrogen bond donors in different proportions. In addition to the low vapor pressure, non-volatility, and good thermal stability of ionic liquids, they also have the characteristics of simple synthesis, low raw material cost, and high atomic utilization. They can be applied to more fields and have attracted the attention of more researchers.

[0004] The dye has a greater affinity for the hydrophobic phase (DES-rich upper phase) than the hydrophilic phase (salt-rich phase). This behavior exhibited by anionic azo dyes is due to their inherent high hydrophobicity. Amaranth was successfully extracted and separated from aqueous solution, and based on experience and experiments, a low eutectic solvent with the lowest cost, simplest operation and best extraction effect can be designed to maximize economic benefits. Summary of the invention

[0005] In order to solve the above problems, the present invention provides a method for preparing a benzyltrimethylol low eutectic solvent and its application in extracting amaranth red dye. The method is simple to operate and has excellent effect.

[0006] To achieve the above object, the technical solution adopted by the present invention is:

[0007] The invention discloses an application of a benzyltrimethylol deep eutectic solvent in extracting amaranth dye, and the method is as follows: placing an ABS solution formed by the benzyltrimethylol deep eutectic solvent and K3PO4 in an aqueous solution containing amaranth, and extracting the amaranth under constant temperature stirring conditions.

[0008] Furthermore, in the above application, the mass fraction of K3PO4 in the ABS solution is 40%, and the concentration of amaranth in the aqueous solution containing amaranth is 0.4 g / L.

[0009] Furthermore, in the above application, the mass ratio of the ABS solution formed by the benzyltrimethylol deep eutectic solvent and K3PO4: the aqueous solution containing amaranth is 1:1.

[0010] Furthermore, in the above application, the temperature of the constant temperature stirring is 25°C.

[0011] Furthermore, in any of the above applications, the benzyltrimethylol deep eutectic solvent is synthesized from benzyltrimethylammonium chloride and triethylene glycol having structural formulas as shown in (I) and (II), respectively.

[0012]

[0013] Furthermore, in the above application, the preparation method of the benzyltrimethylol deep eutectic solvent comprises the following steps:

[0014] 1) vacuum drying benzyltrimethylammonium chloride;

[0015] 2) mixing benzyltrimethylammonium chloride and triethylene glycol and stirring to react until a uniform transparent liquid is formed to obtain a benzyltrimethyltriethylene glycol deep eutectic solvent;

[0016] 3) The benzyltrimethyl triglycol low eutectic solvent is vacuum dried.

[0017] Furthermore, in the preparation method of the above-mentioned benzyltrimethylol low eutectic solvent, in step 1), the vacuum drying condition is: vacuum drying at 60° C. for 12 hours.

[0018] Furthermore, in the above-mentioned method for preparing the benzyltrimethylol deep eutectic solvent, in step 2), the molar ratio of benzyltrimethylammonium chloride to triethylene glycol is 1:3.

[0019] Furthermore, in the above-mentioned method for preparing the benzyltrimethylol low eutectic solvent, in step 2), the stirring reaction time is 3 hours.

[0020] Furthermore, in the preparation method of the above-mentioned benzyltrimethylol low eutectic solvent, in step 3), the vacuum drying conditions are: vacuum drying at 60° C. for 12 hours.

[0021] The beneficial effects of the present invention are:

[0022] 1. The benzyltrimethylol deep eutectic solvent of the present invention has simple synthesis operation and low price.

[0023] 2. The present invention provides an application of a benzyltrimethylol low eutectic solvent in the extraction of amaranth red dye. The dye has a greater affinity for the hydrophobic phase (DES-rich upper phase) than the hydrophilic phase (salt-rich phase), and can successfully extract the amaranth red dye from water with a high extraction rate.

[0024] 3. The present invention provides an application of a benzyltrimethylol low eutectic solvent in the extraction of amaranth dye, which is conducive to the concept of green environmental protection and is more conducive to the life and survival of humans, animals and plants. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is the infrared spectrum of the benzyltrimethyl triglycol low eutectic solvent of Example 1. DETAILED DESCRIPTION

[0026] The present invention is further described below by means of specific examples. The present invention is not limited to the examples, and is also applicable to other deep eutectic solvents, and may be slightly modified without departing from the described scope.

[0027] Example 1 A benzyltrimethylol deep eutectic solvent for extracting amaranth dye (I) Preparation method:

[0028] 1) drying benzyltrimethylammonium chloride under vacuum at 60°C for 12h;

[0029] 2) mixing benzyltrimethylammonium chloride and triethylene glycol in a molar ratio of 1:3 and stirring for reaction for 3 hours until a uniform transparent liquid is formed to obtain a benzyltrimethyltriethylene glycol low eutectic solvent;

[0030] 3) The benzyltrimethyltriglycol low eutectic solvent was dried under vacuum at 60° C. for 12 h.

[0031] (II) Characterization methods:

[0032] Infrared spectrum: infrared characterization of benzyltrimethylol deep eutectic solvent is shown in Figure 1 . Analysis of the infrared spectrum shows that the infrared spectrum of the low eutectic solvent contains both characteristic peaks of the hydrogen bond acceptor (benzyltrimethylammonium chloride) and characteristic absorption peaks of the hydrogen bond donor (triethylene glycol), and no new characteristic peaks are generated, indicating that there is no chemical reaction between benzyltrimethylammonium chloride and triethylene glycol to produce new substances, but they are only combined through hydrogen bond interactions.

[0033] Example 2 Application of a benzyltrimethylol deep eutectic solvent in the extraction of amaranth dye

[0034] (I) Extraction and separation experiment

[0035] 1) Take a certain amount of amaranth and dissolve it in water to prepare an aqueous solution containing amaranth at a concentration of 0.4 g / L for later use.

[0036] 2) Weigh 1 g of the ABS solution formed by the benzyltrimethylol low eutectic solvent and K3PO4 into a 10 mL graduated test tube, add 1 g of the aqueous solution containing amaranth, so that the mass ratio of the ABS solution to the aqueous solution containing amaranth is 1:1, and perform an extraction and separation experiment of amaranth dye at 25°C with magnetic stirring.

[0037] 3) After extraction for 15 minutes, the mixture was allowed to stand for 2 hours. The concentration of amaranth dye in the aqueous phase at a wavelength of 520 nm was measured by UV-visible spectrophotometry. The average value of the three measurements was taken, and the relative error was controlled within 3% to ensure the accuracy of the data.

[0038] The extraction efficiency (E%) of amaranth dye was calculated according to the following formula (1-1):

[0039] E%=[(C0-C f ) / C0] × 100% (1-1)

[0040] Where, C0 represents the initial concentration of amaranth in the aqueous solution containing amaranth, C f is the concentration of remaining amaranth dye in the aqueous phase.

[0041] (II) Extraction rate of amaranth red dye by benzyltrimethylol deep eutectic solvent

[0042] After extraction with benzyltrimethylol deep eutectic solvent, it was calculated that the extraction efficiency of benzyltrimethylol deep eutectic solvent for amaranth dye was 98.1%.

Claims

1. A use of a benzyltrimethylol deep eutectic solvent in extracting amaranth dye, characterized in that: The method is as follows: an ABS solution formed by a benzyltrimethylol low eutectic solvent and K3PO4 is placed in an aqueous solution containing amaranth, and the amaranth is extracted under constant temperature stirring conditions.

2. The use according to claim 1, characterized in that: The mass fraction of K3PO4 in the ABS solution is 40%, and the concentration of amaranth in the aqueous solution containing amaranth is 0.4 g / L.

3. The use according to claim 1, characterized in that: In terms of mass ratio, the ABS solution formed by benzyltrimethylol deep eutectic solvent and K3PO4: the aqueous solution containing amaranth red = 1:

1.

4. The use according to claim 1, characterized in that: The temperature of the constant temperature stirring is 25°C.

5. The use according to any one of claims 1 to 4, characterized in that: The benzyltrimethylol deep eutectic solvent is synthesized from benzyltrimethylammonium chloride and triethylene glycol as shown in the structural formulas (I) and (II), respectively.

6. The use according to claim 5, characterized in that: The preparation method of the benzyltrimethylol deep eutectic solvent comprises the following steps: 1) vacuum drying benzyltrimethylammonium chloride; 2) mixing benzyltrimethylammonium chloride and triethylene glycol and stirring to react until a uniform transparent liquid is formed to obtain a benzyltrimethyltriethylene glycol low eutectic solvent; 3) The benzyltrimethyl triglycol low eutectic solvent is vacuum dried.

7. The use according to claim 6, characterized in that: In step 1), the vacuum drying condition is: vacuum drying at 60° C. for 12 h.

8. The use according to claim 6, characterized in that: In step 2), the molar ratio of benzyltrimethylammonium chloride to triethylene glycol is 1:

3.

9. The use according to claim 6, characterized in that: In step 2), the stirring reaction time is 3 h.

10. The use according to claim 6, characterized in that: In step 3), the vacuum drying condition is: vacuum drying at 60° C. for 12 h.

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