CN-122013513-A - Aza crown ether functionalized polyacrylonitrile fiber, and preparation method and application thereof

CN122013513ACN 122013513 ACN122013513 ACN 122013513ACN-122013513-A

Abstract

The application is applicable to the technical field of materials, and provides an aza crown ether functionalized polyacrylonitrile fiber and a preparation method and application thereof, wherein the aza crown ether functionalized polyacrylonitrile fiber comprises the steps of heating and refluxing polyacrylonitrile fiber, amine compounds and water for 3.5 hours to prepare amino functionalized fiber; and heating and refluxing the fiber with an acylating reagent and an anhydrous organic solvent for 4 hours in a nitrogen atmosphere to obtain an acylated modified fiber, heating and refluxing the acylated modified fiber with 1, 10-diaza-18-crown ether-6, alkali, water and an alcohol solvent for 15 hours, and performing post-treatment to obtain the target fiber. The method has mild and controllable process, the obtained fiber has good mechanical strength, high-efficiency and specific adsorption on Ca 2+ under neutral or alkaline conditions, the saturated adsorption quantity reaches 1.049 mmol and g ‑1 and 30 min, the adsorption balance can be achieved, the adsorption quantity on other metal ions such as Mg 2+ 、Cu 2+ is extremely low, the raw materials are easy to obtain and easy to recycle, and the method can be widely applied to the field of hard water treatment.

Inventors

HOU FAQIU
CHEN ANXUN
Wu Chuangliang
HU XIAOFENG
TAO MINLI

Assignees

广东启润新材料有限公司

Dates

Publication Date: 20260512
Application Date: 20260318

Claims (10)

1. A method for preparing an aza crown ether functionalized polyacrylonitrile fiber, which is characterized by comprising the following steps: Adding polyacrylonitrile fiber, amine compound and water into a reaction vessel, heating and refluxing for 3.5 h, washing and drying to obtain amino functional fiber; under the nitrogen atmosphere, adding amino functionalized fiber, an acylating reagent and an anhydrous organic solvent into a reaction vessel, heating and refluxing 4h, removing impurities, washing and drying to obtain an acylated modified fiber; Adding the acylated modified fiber, 1, 10-diaza-18-crown ether-6, alkali, water and alcohol solvent into a reaction container, heating and refluxing for 15 h, and carrying out suction filtration, washing, extraction and drying to obtain the aza crown ether functionalized polyacrylonitrile fiber.
2. The method for preparing the aza-crown ether functionalized polyacrylonitrile fiber according to claim 1, wherein the amine compound is one or more of ethylenediamine, 1, 3-propylenediamine, N-methyl-1, 3-propylenediamine, N-dimethyl-1, 3-propylenediamine and hydrazine hydrate.
3. The method for preparing the aza-crown ether functionalized polyacrylonitrile fiber according to claim 1, wherein the acylating agent is chloroacetyl chloride, and the anhydrous organic solvent is one of anhydrous acetonitrile and anhydrous ethanol.
4. The method for preparing the aza-crown ether functionalized polyacrylonitrile fiber according to claim 1, wherein the alkali is sodium carbonate, and the alcohol solvent is one or more of ethylene glycol, ethanol and 1, 4-dioxane.
5. The preparation method of the aza-crown ether functionalized polyacrylonitrile fiber according to claim 1, wherein the mass volume ratio of the polyacrylonitrile fiber, the amine compound and the water is 1.00 g:4-6 mL:8-10 mL.
6. The method for preparing the aza-crown ether functionalized polyacrylonitrile fiber according to claim 1, wherein the mass-volume ratio of the amino-functionalized fiber, the acylating agent and the anhydrous organic solvent is 1.00 g:4-6 mL:18-22 mL.
7. The method for preparing the aza-crown ether functionalized polyacrylonitrile fiber according to claim 1, wherein the mass molar ratio of the acylated modified fiber, the 1, 10-diaza-18-crown ether-6 and the base is 1 g:0.018-0.020mol:0.001-0.003mol.
8. The method for preparing the aza-crown ether functionalized polyacrylonitrile fiber according to claim 1, comprising: Adding polyacrylonitrile fiber, ethylenediamine and secondary distilled water into a reaction vessel according to the mass volume ratio of 1.00g to 5mL to 9mL, heating and refluxing for 3.5h, washing with distilled water at 60-70 ℃ until the filtrate is neutral, and drying in vacuum to obtain amino functionalized fiber; Under the nitrogen atmosphere, adding amino functionalized fiber, chloroacetyl chloride and anhydrous acetonitrile into a reaction vessel according to the mass volume ratio of 1.00g to 5mL to 20mL, heating and refluxing for 4 hours, washing with distilled water at 60-70 ℃, detecting with AgNO 3 solution until no Cl - exists, and drying in vacuum to obtain acylated modified fiber; Adding the acylated modified fiber, 1, 10-diaza-18-crown ether-6, sodium carbonate, deionized water and ethylene glycol into a reaction vessel according to the proportion of 1g to 0.019mol to 0.002mol to 5mL to 10mL, heating and refluxing for 15h under electromagnetic stirring, filtering, washing, and obtaining the aza crown ether functionalized polyacrylonitrile fiber through Soxhlet extraction, washing again and vacuum drying.
9. An aza crown ether functionalized polyacrylonitrile fiber obtained by the preparation method according to any one of claims 1 to 8.
10. Use of an aza-crown ether functionalized polyacrylonitrile fiber according to claim 9 in the selective adsorption of calcium ions in water bodies.

Description

Aza crown ether functionalized polyacrylonitrile fiber, and preparation method and application thereof Technical Field The application belongs to the technical field of materials, and particularly relates to an aza crown ether functionalized polyacrylonitrile fiber, and a preparation method and application thereof. Background The water hardness is mainly determined by the total concentration of Ca 2+ and Mg 2+, and the water hardness is in an ascending trend in the coastal areas due to the fact that the precipitation is rare and the calcium magnesium mineral is rich. The higher water hardness not only shortens the service life of industrial equipment and increases potential safety hazards, but also improves the probability of suffering related diseases of human bodies, wherein the influence of Ca 2+ on the water hardness is far greater than that of Mg 2+, so that the reduction of the Ca 2+ content in the water has important practical significance. The current method for reducing Ca 2+ in water mainly comprises membrane filtration, fractionation and adsorption complexation. The membrane filtration method requires higher external force to enable the water body to pass through the filter membrane, has high energy consumption and treatment cost, and still remains high-hardness water body after filtration, has extremely high energy consumption, can generate a large amount of scale at the bottom of the fractionating tower, reduces the boiler efficiency and even blocks the pipeline. The adsorption complexation method can be performed at normal temperature, has low energy consumption, high efficiency and stability, can repeatedly use the adsorbent and is simple and convenient to operate. Functional groups of the micromolecular adsorbent are loaded on a carrier to prepare the shaped and easily recovered adsorbent, which is a development direction of environmental protection. In the prior art, research on natural rubber immobilized alpha-Fe 2O3, mercerized cellulose immobilized ethylenediamine tetraacetic anhydride and other immobilized adsorption materials proves the application potential of the macromolecule carrier immobilized micromolecule adsorbent in the field of hardness reduction. The polyacrylonitrile fiber (PANF) has excellent chemical stability and low cost, the surface contains cyano groups and ester groups with high reactivity, can realize deep and high-density surface modification, is easy to manually recycle, and is an ideal adsorbent carrier. The cyclic polyether structure of the crown ether can be complexed with alkali metal ions, and the improved aza crown ether can be used for effectively complexing alkaline earth metal ions. In the prior art, however, the technology of grafting the aza crown ether onto the polyacrylonitrile fiber through chemical modification and realizing the selective adsorption of Ca 2+ in water is rarely reported, and meanwhile, in the preparation process of the aza crown ether functional chemical fiber, if the aza crown ether functional chemical fiber is improperly controlled, the problems of reduced mechanical strength, limited adsorption volume and the like of the fiber are caused, so that the adsorption performance and the practical application performance are difficult to be simultaneously considered. Disclosure of Invention The embodiment of the application aims to provide a preparation method of aza crown ether functionalized polyacrylonitrile fiber, which aims to solve the technical problems that in the prior art, the water body hardness reduction method has high energy consumption and poor applicability, the immobilized calcium adsorption material lacks selectivity, and the fiber-based adsorption material is difficult to prepare and has both modification degree and mechanical strength. The embodiment of the application is realized in such a way that the preparation method of the aza crown ether functionalized polyacrylonitrile fiber comprises the following steps: Adding polyacrylonitrile fiber, amine compound and water into a reaction vessel, heating and refluxing for 3.5 h, washing and drying to obtain amino functional fiber; under the nitrogen atmosphere, adding amino functionalized fiber, an acylating reagent and an anhydrous organic solvent into a reaction vessel, heating and refluxing 4h, removing impurities, washing and drying to obtain an acylated modified fiber; Adding the acylated modified fiber, 1, 10-diaza-18-crown ether-6, alkali, water and alcohol solvent into a reaction container, heating and refluxing for 15 h, and carrying out suction filtration, washing, extraction and drying to obtain the aza crown ether functionalized polyacrylonitrile fiber. Another object of an embodiment of the present application is an aza-crown ether functionalized polyacrylonitrile fiber obtained by the above preparation method. Another object of the embodiment of the application is to use the aza-crown ether functionalized polyacrylonitrile fiber in the selective absorption o