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CN-120384207-B - Membrane separation and extraction method of ionic rare earth

CN120384207BCN 120384207 BCN120384207 BCN 120384207BCN-120384207-B

Abstract

The application discloses a membrane separation and extraction method of ionic rare earth, which belongs to the technical field of rare earth extraction and is used for solving the technical problems of large environmental pollution caused by extracting ionic rare earth from rare earth minerals, low extraction rate and difficult extraction of ionic rare earth by membrane direct filtration and separation in the prior art. The application optimizes the elution process of rare earth minerals and is matched with the adsorption filler prepared by the application, thereby not only effectively improving the extraction rate of ionic rare earth and the adsorption capacity of the adsorption filler to the ionic rare earth, but also effectively reducing the pollution and the production cost of the ionic rare earth extraction to ecological soil.

Inventors

  • NIE JINRONG
  • LU YUJIN

Assignees

  • 广东立源环保科技有限公司

Dates

Publication Date
20260508
Application Date
20250428

Claims (9)

  1. 1. The membrane separation and extraction method of the ionic rare earth is characterized by comprising the following steps of: S1, loading dry ionic rare earth ores into a leaching column, adding impregnating solution into the leaching column, enabling the impregnating solution to completely permeate the ionic rare earth ores, preserving heat and impregnating for 2-3 hours at room temperature, and leaching and eluting by using leaching solution to obtain eluent; S2, delivering the eluent into a pH adjusting tank, adjusting the pH of a system to be between 5.7 and 5.9, filtering, carrying out nanofiltration adsorption on filtrate through a nanofiltration adsorption film group filled with adsorption filler, and then desorbing and eluting to prepare nanofiltration concentrated solution; s3, performing alkaline precipitation on the nanofiltration concentrated solution, and filtering and roasting to obtain ionic rare earth; the adsorption filler is obtained by processing the following steps: A1, adding graphene oxide, sulfonated cellulose, hydroxypropyl distarch phosphate and sodium hydroxide into deionized water, performing ultrasonic dispersion for 40-60min, adding an emulsion into a reaction system in a stirring state, stirring for 20-30min, increasing the reaction temperature to 60-70 ℃, adding an epoxy resin solution into the reaction system, performing heat preservation reaction for 2-3h, performing aftertreatment, and adsorbing a filler precursor; A2, mixing and stirring an adsorption filler precursor, triethoxysilane modified PAN and absolute ethyl alcohol, increasing the temperature of a reaction system to 50-60 ℃, adding a catalyst into the reaction system, carrying out heat preservation reaction for 80-90min, and carrying out aftertreatment to obtain the adsorption filler, wherein the triethoxysilane modified PAN is obtained by carrying out condensation reaction on hydroxyl on 1- (2-pyridine azo) -2-naphthol molecules and isocyanate groups on isocyanatopropyl triethoxysilane molecules.
  2. 2. The method for membrane separation and extraction of ionic rare earth according to claim 1, wherein in the step S1, the volume ratio of the immersion liquid to the leaching solution is 1:3, the immersion liquid is obtained by adjusting the ph=3 to 3.6 of a magnesium sulfate solution with a concentration of 0.3 to 0.5mol/L composed of magnesium sulfate and purified water, and the leaching solution is obtained by adjusting the ph=5 of a magnesium sulfate solution with a concentration of 0.08 to 0.12mol/L composed of magnesium sulfate and purified water.
  3. 3. The membrane separation and extraction method of the ionic rare earth according to claim 1, wherein in the step S2, the nanofiltration adsorption membrane group comprises a dialysis membrane bag and an adsorption filler, the adsorption filler is filled in the dialysis membrane bag, the molecular weight cut-off of the dialysis membrane bag is 13000-15000, the desorption elution method comprises the steps of adding the adsorption saturated adsorption filler into an elution column, circularly eluting the elution liquid for 30-50min, circularly eluting the elution liquid for 20-30min by using purified water, combining the elution liquid to obtain nanofiltration concentrated solution, taking the adsorption filler out of the elution column, washing the adsorption filler to be neutral by using purified water to obtain regenerated adsorption filler, the volume ratio of the adsorption saturated adsorption filler, the elution liquid and the purified water is 1:7:3, and the elution liquid is 0.8-1.2mol/L sulfuric acid aqueous solution.
  4. 4. The membrane separation and extraction method of the ionic rare earth according to claim 1, wherein in the step S3, sodium hydroxide is added into nanofiltration concentrated solution, the pH value of a system is regulated to be 10, suction filtration is carried out, filter cakes are washed to be neutral by purified water and then pumped to be dried, the filter cakes are transferred into a drying box with the temperature of 70-80 ℃ and dried for 4-6 hours, and then transferred into a roasting furnace with the temperature of 500-550 ℃ and are roasted for 3-5 hours in a heat preservation way, so that the ionic rare earth is obtained.
  5. 5. The membrane separation and extraction method of the ionic rare earth according to claim 1, wherein in the step A1, the dosage ratio of graphene oxide, sulfonated cellulose, hydroxypropyl distarch phosphate, sodium hydroxide, deionized water, emulsion and epoxy resin solution is 1g to 3g to 5g to 0.5g to 30mL to 20mL to 10mL, and in the step A2, the dosage ratio of the adsorption filler precursor, triethoxysilane modified PAN, absolute ethyl alcohol and catalyst is 5g to 1g to 30mL to 7mL, and the catalyst is 0.5mol/L sodium hydroxide solution.
  6. 6. The method for separating and extracting the ionic rare earth membrane according to claim 1, wherein the preparation method of the triethoxysilane modified PAN is characterized in that under the protection of inert gas, 1- (2-pyridine azo) -2-naphthol and tetrahydrofuran are stirred and mixed, the temperature of a reaction system is increased to 40-50 ℃, the isocyanatopropyl triethoxysilane is added into the reaction system, and the reaction is carried out for 40-60min under the heat preservation, so that the triethoxysilane modified PAN is obtained.
  7. 7. The method for separating and extracting the ionic rare earth by using the membrane according to claim 6, wherein the dosage ratio of 1mol to 1mol of 1- (2-pyridine azo) -2-naphthol to propyltriethoxysilane is 1g to 7mL of 1- (2-pyridine azo) -2-naphthol to tetrahydrofuran.
  8. 8. The membrane separation and extraction method of ionic rare earth according to claim 1, wherein the preparation method of sulfonated cellulose is characterized in that ‌ hydroxypropyl cellulose and N, N-dimethylformamide are stirred and mixed under the protection of inert gas, the reaction temperature is reduced to 0-5 ℃, chlorosulfonic acid solution is dropwise added into a reaction system, the reaction system is naturally heated to 25-35 ℃ after the dropwise addition is completed, the reaction is carried out for 3-4 hours under the condition of heat preservation, and the sulfonated cellulose is obtained after the post-treatment.
  9. 9. The membrane separation and extraction method of ionic rare earth according to claim 8, wherein the dosage ratio of ‌ hydroxypropyl cellulose, N-dimethylformamide to chlorosulfonic acid solution is 10g:70mL:7mL, and the chlorosulfonic acid solution consists of chlorosulfonic acid and N, N-dimethylformamide according to 1g:3 mL.

Description

Membrane separation and extraction method of ionic rare earth Technical Field The invention relates to the technical field of rare earth extraction, in particular to a membrane separation and extraction method of ionic rare earth. Background The ion type is a rare earth mineral which is absorbed on minerals such as kaolin, montmorillonite and the like in an ion form, most of which are like earth, the content is 0.3-0.05%, and the rare earth mineral can be leached out by electrolyte. The ionic rare earth ore is an important strategic resource in China, and the extraction technology directly relates to the resource utilization rate and the environmental protection. In the prior art, the method for extracting rare earth from rare earth minerals is usually carried out by leaching the rare earth minerals with high-concentration sulfuric acid or hydrochloric acid, so as to improve the extraction rate of ionic rare earth, various ammonia nitrogen compounds are added into the rare earth minerals, on one hand, a large amount of acidic wastewater is discharged, the impurity ions such as iron and aluminum in the leaching solution are high in content, the subsequent separation cost is obviously increased, on the other hand, the ammonia nitrogen compounds are remained in mineral soil for a long time and cause serious pollution to the soil environment, the membrane separation technology is carried out by nano filtration interception, the separation of rare earth ions and alkaline earth is realized, the concentration of eluent is avoided, and the production cost is reduced, but when ionic rare earth is extracted by membrane separation, the ionic rare earth is usually in gel shape to block a die hole, so that the membrane separation is difficult. In view of the technical drawbacks of this aspect, a solution is now proposed. Disclosure of Invention The invention aims to provide a membrane separation and extraction method of ionic rare earth, which is used for solving the technical problems of great environmental pollution caused by extracting ionic rare earth from rare earth minerals, low extraction rate and difficult operation of directly filtering, separating and extracting ionic rare earth by a membrane in the prior art. The aim of the invention can be achieved by the following technical scheme: A membrane separation and extraction method of ionic rare earth comprises the following steps: S1, loading dry ionic rare earth ores into a leaching column, adding impregnating solution into the leaching column, enabling the impregnating solution to completely permeate the ionic rare earth ores, preserving heat and impregnating for 2-3 hours at room temperature, and leaching and eluting by using leaching solution to obtain eluent; S2, delivering the eluent into a pH adjusting tank, adjusting the pH of a system to be between 5.7 and 5.9, filtering, carrying out nanofiltration adsorption on filtrate through a nanofiltration adsorption film group filled with adsorption filler, and then desorbing and eluting to prepare nanofiltration concentrated solution; s3, filtering and roasting the nanofiltration concentrated solution after alkaline precipitation to obtain the ionic rare earth. Further, in the step S1, the volume ratio of the infiltration liquid to the leaching liquid is 1:3, the length-diameter ratio of the leaching column is 3:1, the bottom of the leaching column is provided with a interception filter cloth, the infiltration liquid is obtained by adjusting pH value of a magnesium sulfate solution with concentration of 0.3-0.5mol/L composed of magnesium sulfate and purified water to 3-3.6 through sulfuric acid, and the leaching liquid is obtained by adjusting pH value of a magnesium sulfate solution with concentration of 0.08-0.12mol/L composed of magnesium sulfate and purified water to 5 through sulfuric acid. In step S2, the nanofiltration adsorption film group comprises a dialysis film bag and an adsorption filler, wherein the adsorption filler is filled in the dialysis film bag, the interception molecular weight of the dialysis film bag is 13000-15000, the desorption elution method comprises the steps of adding the adsorption saturated adsorption filler into an elution column, circularly eluting the elution column for 30-50min with eluent, circularly eluting the elution column for 20-30min with purified water, merging the eluent to obtain nanofiltration concentrated solution, taking the adsorption filler out of the elution column, washing the adsorption filler to be neutral with purified water to obtain regenerated adsorption filler, the volume ratio of the adsorption saturated adsorption filler, the eluent and the purified water is 1:7:3, the eluent is 0.8-1.2mol/L sulfuric acid aqueous solution, and the length-diameter ratio of the elution column is 8:1. In the step S3, sodium hydroxide is added into the nanofiltration concentrated solution, the pH value of the system is regulated to be 10, the solution is subjected to su