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CN-121975052-A - Chelate resin for removing calcium and magnesium ions in water and preparation method and application thereof

CN121975052ACN 121975052 ACN121975052 ACN 121975052ACN-121975052-A

Abstract

The invention relates to the technical field of separation, and relates to a chelate resin for removing calcium and magnesium ions in water, and a preparation method and application thereof. The chelate resin for removing calcium and magnesium ions in water provided by the invention is composed of matrix resin and modified groups, the adsorption capacity and stability of the matrix resin to the calcium and magnesium ions are improved at the same time by introducing the modified groups, the concentration of the calcium ions and the magnesium ions in high-salt sewage can be respectively reduced to below 0.5ppm, the capacity is still kept above 85% after the high-salt sewage is recycled for 15 times, the sewage treatment cost is greatly reduced, and the high-salt sewage treatment method has a wide application prospect.

Inventors

  • LIN GUANGYUE
  • LIN XIONGSHUI
  • CHANG KAI
  • LAN YUNCAI
  • ZHANG YONG

Assignees

  • 同舟纵横（厦门）流体技术有限公司

Dates

Publication Date
20260505
Application Date
20260408

Claims (10)

  1. 1. The chelate resin for removing calcium and magnesium ions in water is characterized by having the following structural formula: , wherein PD represents matrix resin, which is macroporous polystyrene-divinylbenzene resin microsphere with a crosslinking degree of 1% -10%.
  2. 2. The chelating resin for removing calcium and magnesium ions from water according to claim 1, wherein said matrix resin has a particle size of 100 to 200 mesh.
  3. 3. The chelating resin for removing calcium and magnesium ions from water according to claim 1, wherein the water is high-salt sewage, the concentration of sodium ions or potassium ions in the high-salt sewage is not lower than 5000mg/L, and the concentration of calcium ions or magnesium ions is 50-200mg/L.
  4. 4. A process for preparing chelate resin for removing Ca and Mg ions from water according to any one of claims 1-3, which comprises chloromethylating matrix resin, sequentially reacting the chloromethylated matrix resin with ethylenediamine and thienopyridine-2-carboxylic acid, and acylating with propionyl chloride.
  5. 5. The method for preparing chelate resin for removing calcium and magnesium ions in water according to claim 4, wherein the step of chloromethylating the matrix resin comprises the steps of adding the matrix resin into dichloroethane for swelling, adding zinc chloride, stirring for dissolving, adding chloromethyl ether for reflux reaction at 40-45 ℃ for 8-12h, filtering, washing and drying to obtain chloromethylated matrix resin.
  6. 6. The method for preparing chelate resin for removing calcium and magnesium ions in water according to claim 5, wherein the mass-volume ratio of the matrix resin to dichloroethane is 1g:4-6mL, the addition amount of zinc chloride is 25% -35% of the mass of the matrix resin, and the mass-volume ratio of the matrix resin to chloromethyl ether is 1g:1-2mL.
  7. 7. The method for preparing chelate resin for removing calcium and magnesium ions in water according to claim 4, wherein the step of sequentially reacting chloromethylated matrix resin with ethylenediamine and thienopyridine-2-carboxylic acid comprises the steps of swelling chloromethylated matrix resin in N, N-dimethylformamide, slowly dropwise adding ethylenediamine, stirring at 70-80 ℃ for reaction for 20-24 hours, filtering, washing and drying after the reaction is finished to obtain aminated matrix resin, dissolving thienopyridine-2-carboxylic acid, 1-ethyl-3- (3-dimethylaminopropyl) carbodiimide hydrochloride and N-hydroxysuccinimide in 2-morpholinoethanesulfonic acid, stirring at room temperature for 20-30 minutes, slowly dropwise adding to the aminated matrix resin swelled in N, N-dimethylformamide, stirring at room temperature for reaction for 18-20 hours under the protection of nitrogen, filtering, washing and drying after the reaction is finished to obtain thienopyridine-2-carboxylic acid grafted resin.
  8. 8. The method for preparing chelate resin for removing calcium and magnesium ions in water according to claim 7, wherein the mass-volume ratio of chloromethylation matrix resin or amination matrix resin to N, N-dimethylformamide is 1g to 8-10mL, the mass-volume ratio of chloromethylation matrix resin to ethylenediamine is 1g to 2-3mL, the mass ratio of chloromethylation matrix resin to thienopyridine-2-carboxylic acid is 1:0.3-0.4, and the mass ratio of thienopyridine-2-carboxylic acid, 1-ethyl-3- (3-dimethylaminopropyl) carbodiimide hydrochloride and N-hydroxysuccinimide is 1:1-1.5:0.7-0.9 in sequence, and the mass-volume ratio of thienopyridine-2-carboxylic acid to 2-morpholinoethanesulfonic acid is 1g to 15-20mL.
  9. 9. The method for preparing chelate resin for removing calcium and magnesium ions in water according to claim 4, wherein the step of acylation by propionyl chloride comprises the steps of swelling thienopyridine-2-carboxylic acid grafted resin in dichloroethane, adding propionyl chloride, stirring at room temperature for reaction for 5-8h, filtering, washing and drying to obtain chelate resin for removing calcium and magnesium ions in water, wherein the mass-volume ratio of thienopyridine-2-carboxylic acid grafted resin to dichloroethane is 1g:4-5mL, and the mass ratio of thienopyridine-2-carboxylic acid grafted resin to propionyl chloride is 1:0.3-0.5.
  10. 10. Use of the chelating resin for removing calcium and magnesium ions in water according to any one of claims 1 to 3 for separating and removing calcium and magnesium ions in water.

Description

Chelate resin for removing calcium and magnesium ions in water and preparation method and application thereof Technical Field The invention belongs to the technical field of separation, and particularly relates to chelate resin for removing calcium and magnesium ions in water, and a preparation method and application thereof. Background Currently, in the treatment of high-salt wastewater, resin adsorption is often used to remove calcium ions and magnesium ions, but high-salt wastewater generally contains high concentrations of monovalent cations such as Na +、K+ and anions such as Cl -、SO42-. However, the active functional groups of existing chelating resins, such as amino phosphonic acid groups or amino carboxylic acid groups, are not specifically selected for Ca 2+ and Mg 2+, and monovalent cations compete with calcium and magnesium ions for the adsorption sites of the resin. When the concentration of Na + and K + in sewage is far higher than that of calcium and magnesium ions (hundreds times or even thousands times of the concentration of the calcium and magnesium ions), a large amount of active sites of the resin are occupied by sodium ions or potassium ions in an ion exchange mode, so that the adsorption capacity of the resin on Ca 2+ and Mg 2+ is greatly reduced, even the penetration phenomenon of 'adsorption saturation advance' occurs, and the removal efficiency of calcium and magnesium is greatly reduced. In addition, the high-salt sewage is easy to damage the resin structure, so that the swelling degree of the resin is reduced and the adsorption performance is deteriorated in the subsequent repeated use. Disclosure of Invention Aiming at the technical problems, the invention provides a chelate resin for removing calcium and magnesium ions in water, a preparation method and application thereof, the anti-chelate resin can be more prone to selectively adsorb the calcium ions and the magnesium ions in high-salt sewage, meanwhile, the high-temperature-resistant porous ceramic material has higher structural stability, can be repeatedly utilized in a high-salt environment, and keeps higher adsorption effect. In a first aspect, the invention provides a chelate resin for removing calcium and magnesium ions in water, wherein the chelate resin has the following structural formula: , wherein PD represents matrix resin, which is macroporous polystyrene-divinylbenzene resin microsphere with a crosslinking degree of 1% -10%. Macroporous polystyrene-divinylbenzene resin microspheres (PS/DVB resin), also called polystyrene resin, with the product number of P118278, wherein the particle size of the matrix resin is 100-200 meshes. Preferably, the water is high-salt sewage, the concentration of sodium ions or potassium ions in the high-salt sewage is not lower than 5000mg/L, and the concentration of calcium ions or magnesium ions is 50-200mg/L. Preferably, the concentration of sodium ions or potassium ions in the high-salt sewage is not lower than 7000mg/L, and the concentration of calcium ions or magnesium ions is 100-200mg/L. In a second aspect, the invention provides a preparation method of the chelate resin for removing calcium and magnesium ions in water, which comprises the steps of chloromethylating matrix resin, sequentially reacting the obtained chloromethylated matrix resin with ethylenediamine and thienopyridine-2-carboxylic acid, and finally acylating with propionyl chloride to obtain the chelate resin. Preferably, the chloromethylation of the matrix resin comprises the steps of adding the matrix resin into dichloroethane for swelling, adding zinc chloride, stirring for dissolving, adding chloromethyl ether for reflux reaction at 40-45 ℃ for 8-12h, filtering, washing and drying to obtain chloromethylation matrix resin. Preferably, the mass volume ratio of the matrix resin to the dichloroethane is 1g:4-6mL, the addition amount of the zinc chloride is 25% -35% of the mass of the matrix resin, and the mass volume ratio of the matrix resin to the chloromethyl ether is 1g:1-2mL. The chloromethylation matrix resin is swelled in N, N-dimethylformamide, slowly dropwise added with ethylenediamine, stirred and reacted for 20-24 hours at 70-80 ℃ to obtain aminated matrix resin, the thienopyridine-2-carboxylic acid, 1-ethyl-3- (3-dimethylaminopropyl) carbodiimide hydrochloride and N-hydroxysuccinimide are dissolved in 2-morpholinoethanesulfonic acid, stirred for 20-30 minutes at room temperature, then slowly dropwise added into the aminated matrix resin swelled in N, N-dimethylformamide, stirred and reacted for 18-20 hours at room temperature under the protection of nitrogen, filtered, washed and dried after the reaction is finished to obtain the thienopyridine-2-carboxylic acid grafted resin. Preferably, the mass volume ratio of the chloromethylation matrix resin or the aminated matrix resin to N, N-dimethylformamide is 1g to 8-10mL, the mass volume ratio of the chloromethylation matrix resin to ethylenediamine is 1g