CN-122006823-A - Modified cation exchange resin, modification method and application thereof

CN122006823ACN 122006823 ACN122006823 ACN 122006823ACN-122006823-A

Abstract

The invention belongs to the technical field of cation exchange resin modification, and in particular relates to a modified cation exchange resin, a modification method and application thereof, wherein the modification method comprises the following steps of (1) washing a basic cation exchange resin; (2) contacting the washed cation exchange resin with a modifier containing functional groups for reaction, then contacting the washed cation exchange resin with a chelating agent for reaction to obtain a modified cation exchange resin i, or contacting the washed cation exchange resin with the chelating agent for reaction, then contacting the washed cation exchange resin with the modifier containing functional groups for reaction to obtain a modified cation exchange resin i, (3) compositing the modified cation exchange resin i with a nanomaterial to obtain the modified cation exchange resin ii. The modified resin can prevent the resin from being poisoned in an organic amine system, especially in the purification of an iron-containing organic amine solution, improve the adsorption capacity of the resin and realize the high-selectivity removal of iron ions.

Inventors

ZHANG XIN
YAO XUAN
ZHONG HONGLING
QU YUNXIANG
SONG PENG
CUI HAIWEI

Assignees

国能龙源环保有限公司

Dates

Publication Date: 20260512
Application Date: 20260312

Claims (10)

1. A method for modifying a cation exchange resin, comprising the steps of: (1) Washing the basic cation exchange resin; (2) The washed cation exchange resin is contacted with a modifier containing functional groups to react, and then is contacted with a chelating agent to react, so as to obtain modified cation exchange resin i; Or alternatively The washed cation exchange resin is contacted with a chelating agent for reaction, and then is contacted with a modifier containing functional groups for reaction, so that modified cation exchange resin i is obtained; (3) Compounding the modified cation exchange resin i with a nano material to obtain modified cation exchange resin ii; optionally, the modification method further comprises the steps of washing the modified cation exchange resin ii to remove unreacted chemical reagent, and finally drying the modified cation exchange resin to obtain the modified resin.
2. The method of claim 1, wherein the functional group-containing modifier is selected from one or more of vinylamine, propenyl amine, and vinyl diamine.
3. The method according to claim 1, wherein the reaction conditions with the functional group-containing modifier include a reaction temperature of 50 to 60℃for a reaction time of 4 to 8h and a reaction pH of 1 to 3.
4. The method according to claim 1, wherein the mass ratio of the functional group-containing modifier to the cation exchange resin is 1.5 to 2:1.
5. The modification process according to claim 1, wherein the chelating agent is selected from EDTA, DTPA or a combination thereof; the mass ratio of the chelating agent to the cation exchange resin is 1 (0.8-1.2).
6. The method according to claim 1, wherein the conditions for the reaction with the chelating agent include a reaction temperature of 85-90 ℃, a reaction time of 10-12 h, and a reaction pH of 8-9.
7. The method according to any one of claims 1 to 6, wherein the operation conditions for compounding with the nanomaterial in the step (3) include a temperature of 60 to 80 ℃, a time of 4 to 6 hours, and a ph of 2 to 3; The mass ratio of the nano material to the cation exchange resin is (0.15-0.25): 1; the nanomaterial is nano aluminum oxide, nano silicon oxide or a combination thereof.
8. A modified cation exchange resin for use in the removal of iron ions from an organic amine system, characterized in that it is said modified resin produced by the modification process according to any one of claims 1 to 7.
9. The modified cation exchange resin of claim 8, wherein the modified resin has an adsorption capacity for iron ions of greater than or equal to 90 mg/g; the iron ion adsorption capacity of the modified resin is more than 55% of the adsorption capacity of the unmodified resin; After 5 times of recycling, the adsorption capacity of the modified resin is maintained to be more than 80% of the initial adsorption capacity.
10. The modified cation exchange resin prepared by the modification method according to any one of claims 1 to 7 is applied to the fields of metal ion removal, wastewater treatment, metal recovery and environmental remediation in an organic amine system; Preferably, the modified cation exchange resin is used to adsorb iron ions in an organic amine system.

Description

Modified cation exchange resin, modification method and application thereof Technical Field The invention belongs to the technical field of cation exchange resin modification, and particularly relates to a modified cation exchange resin, a modification method and application thereof. Background Cation exchange resin is a high molecular compound with a reticular three-dimensional structure, and is widely applied to various fields including electric power, petroleum, chemical industry, electronics, food fermentation, drinking water, medicine, biological medicine, nonferrous metal, new energy, military, steel and the like. Since the organic amine liquid often contains high concentration of amine substances and various metal ions (such as iron, lead, copper, nickel, etc.), the metal ions may cause poisoning of the resin when competing with exchange sites of the resin. Resin "poisoning" refers to a decrease in the exchange capacity and adsorption capacity of the resin, and the resin surface active sites become occupied or form unstable complexes with metal ions, ultimately leading to resin failure. Therefore, how to prevent the poisoning of cation exchange resin in an organic amine system and improve the selective removal capability of the resin to iron ions is a technical problem to be solved currently. Cation exchange resins are often used to remove iron ions from organic amine systems. However, the existing resins have the following disadvantages in practical applications: (1) Resin poisoning, namely, competition of specific metal ions (such as calcium, magnesium and the like) with active sites on the surface of the resin, so that the resin is invalid and the adsorption capacity is reduced; (2) The adsorption capacity of the resin is reduced under the interference of high-concentration metal ions, and the selectivity of the resin to target iron ions is poor; (3) Poor stability, i.e., long-term exposure to organic amines and metal ions, the resin may undergo degradation or structural changes, resulting in reduced performance; (4) The selectivity is not high, the resin is easy to compete with a plurality of metal ions in a complex system, and the removal efficiency of target iron ions is affected; (5) Surface contamination amine species and organic compounds may deposit on the resin surface, blocking active sites, degrading performance. Therefore, there is a need to develop a technique for modifying cation exchange resins to solve the above-mentioned problems. Disclosure of Invention The invention aims at solving some problems existing when the cation exchange resin removes iron ions in an organic amine system, and provides a modified cation exchange resin, a modification method and application thereof, wherein functional chemical groups (such as amino groups, carboxyl groups, thiol groups and the like) with lipophilic groups are introduced into the surface of basic cation exchange resin, so that the adsorption capacity of the resin to the iron ions is enhanced, and meanwhile, the competitive adsorption of the resin and other metal ions is reduced, so that the service life of the resin is prolonged; can prevent the resin from being poisoned in an organic amine system, especially improves the adsorption capacity of the resin in the purification treatment process of an iron-containing organic amine solution, and realizes high-selectivity removal of iron ions. In order to achieve the above object, the present invention provides the following technical solutions: In a first aspect, there is provided a method of modifying a cation exchange resin comprising the steps of: (1) Washing the basic cation exchange resin; for example, the basic cation exchange resin can be soaked in deionized water to remove impurities and inactive substances in the resin, then washed with an alcohol solvent (such as methanol), and dried for later use; (2) The washed cation exchange resin is contacted with a modifier containing functional groups to react, and then is contacted with a chelating agent to react, so as to obtain modified cation exchange resin i; Or alternatively The washed cation exchange resin is contacted with a chelating agent for reaction, and then is contacted with a modifier containing functional groups for reaction, so that modified cation exchange resin i is obtained; The functional group can be subjected to grafting reaction with the surface of the resin through chemical reaction; (3) Compounding the modified cation exchange resin i with a nano material to obtain modified cation exchange resin ii; For example, by compounding a nanomaterial on the surface of a resin, the surface area and adsorption capacity of the resin can be improved; Optionally, the modification method further comprises washing the modified cation exchange resin ii to remove unreacted chemical reagent, and finally drying the modified cation exchange resin ii (the drying temperature can be 40-70 ℃ and the drying time can be 10-20 h) to obtain the modi