Efficient separation and recovery method for rare earth and leaching agent in rare earth leaching solution

Abstract

The invention discloses an efficient separation and recovery method for rare earth and a leaching agent in rare earth leaching liquid. Comprising the following steps: obtaining the ion adsorption type rare earth ore leaching mother liquor, pretreating (settling, flocculating and filtering) the leaching mother liquor, activating a rare earth element chemical bond of the leaching mother liquor, activating a surface functional group of a transformation material, reconstructing the rare earth element chemical bond of the mother liquor and recovering a leaching agent, and breaking the rare earth element chemical bond of the transformation material and recovering a rare earth ore concentrate product. The rare earth and the leaching agent in the rare earth leaching mother liquor are efficiently and synchronously recycled through selective separation, the concentration of the rare earth mother liquor is increased, the circulating water amount in the rare earth recycling link is reduced, and the circulating time of the leaching agent is shortened; two independent water systems are formed in the rare earth recovery link and the cyclic leaching link, so that mutual interference of the two links is avoided, the land cost is saved, and the risk of pollution exposure of a leaching agent is reduced; various precipitation processes can be selected in the independent rare earth recovery link, so that the industrial wastewater in the recovery link is effectively prevented from flowing back to a mining area.

Description

Technical Field

[0001] The invention belongs to the field of mining, mineral processing and hydrometallurgical utilization, and particularly relates to a method for efficiently separating and recovering rare earth and a leaching agent in a rare earth leaching solution. Background Art

[0003] Since the rare earth grade in ionic rare earth ores is generally low (0.05-0.2wt%), it is extremely difficult to improve its industrial grade through traditional gravity separation, magnetic separation, electrostatic separation and flotation technologies. Therefore, the current mainstream process is based on the principle of cation exchange extraction. The rare earth elements in the minerals are leached in situ through cationic leaching agents such as ammonium salts (ammonium sulfate), magnesium salts (magnesium sulfate) and calcium salts (calcium chloride) to obtain a high-concentration rare earth mother liquor. Subsequently, the rare earth elements in the leached mother liquor are precipitated through impurities, solid-liquid separation, and roasting to obtain rare earth oxide concentrate products, which are finally further extracted and separated into rare earth products. In this mainstream process link, the separation and recovery stage of rare earth leaching mother liquor involves a large amount of industrial water circulation process, which brings huge construction land costs and pollution exposure risks. Taking the traditional ammonium salt in situ leaching process with an annual output of 2,000 tons of rare earth concentrate as an example, the daily processing of 8,000m 3 The rare earth leaching mother liquor needs to go through the ammonium bicarbonate impurity removal process for about 8 hours and ammonium bicarbonate precipitation for 6 hours in batches before the recyclable leaching agent and rare earth concentrate crude product can be obtained. In this process, the daily industrial circulating water volume is about 8000m 3 , the ammonia nitrogen concentration is about 2000ppm, far exceeding the ammonia nitrogen limit of Class III surface water in GB 3838-2002 standard, and the treatment cost is as high as 300,000 yuan / year. The magnesium salt in situ leaching-precipitation process and the calcium salt in situ leaching process also face similar bottleneck problems. The separation and recovery stage involves a large amount of industrial water circulation process and high concentration of inorganic salts (Mg 2+ , Ca 2+ , SO 4 2- ) exposure risk. In recent years, researchers have developed a magnesium salt in-situ leaching-centrifugal extraction process to further improve the recovery efficiency of high-value rare earth elements in the rare earth leaching mother liquor separation and recovery stage. This process efficiently and quickly realizes the enrichment process of high-concentration rare earth mother liquor, but the centrifugal extraction integrated device is expensive and has high subsequent operating costs, increasing the direct cost by about 30% per ton of REO. In addition, the highly toxic extract and the raffinate directly returned to the mining area will further increase the risk of exposure to pollution in the mine ecological environment.

[0004] Therefore, in order to solve the high cost problem and pollution exposure risk caused by the large amount of industrial circulating water in the leaching mother liquor separation and recovery stage in the current ionic rare earth mining process, the present invention discloses a method for efficiently separating and recovering rare earths and leaching agents in rare earth leachate. By separating the rare earth recovery link and the circulating leaching link into two independent water metallurgical systems, the recovery cost of rare earth concentrate products can be effectively reduced while realizing the rapid reuse process of the leaching agent. Summary of the invention

[0005] The purpose of the present invention is to provide a method for efficiently separating and recovering rare earth and leaching agent in rare earth leachate, and to effectively solve the common defects and bottlenecks existing in the separation and recovery of rare earth leaching mother liquor in the mining process of inorganic salts such as ammonium salts, magnesium salts and calcium salts based on the cation exchange extraction principle.

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

[0007] A method for efficiently recovering rare earth and leaching agent from ionic rare earth ore leaching mother liquor comprises the following steps:

[0008] S1. Obtaining ion adsorption type rare earth ore leaching mother liquor;

[0009] S2, pretreatment of leaching mother liquor (sedimentation, flocculation, filtration);

[0010] S3, chemical bond activation of rare earth elements in leaching mother liquor;

[0011] S4, activation of functional groups on the surface of transition materials;

[0012] S5, reconstruction of chemical bonds of rare earth elements in mother liquor and recovery of leaching agent;

[0013] S6. Breaking of chemical bonds of rare earth elements in transition materials and recovery of rare earth concentrate products;

[0014] Furthermore, in step S1, the ionic rare earth ore leaching mother liquor source may include leaching mother liquor obtained by conventional cation exchange leaching processes such as ammonium salt, magnesium salt, calcium salt and aluminum salt;

[0015] Furthermore, in step S2, the purpose of the sedimentation treatment is to remove large particles of mud, gravel and other insoluble matter by natural sedimentation, and the sedimentation time is 2 to 5 hours; the purpose of the flocculation treatment is to remove suspended matter and most of the colloidal matter, and the flocculants used include but are not limited to organic polymer flocculants such as sodium polyacrylate, dimethyl diallyl ammonium chloride and polyacrylamide, and the flocculation time is 2 to 5 hours; the purpose of the filtration treatment is to further remove suspended matter and colloidal matter to ensure the efficient operation of subsequent transformation materials, and the filtration methods used include but are not limited to bag filtration, multi-media filtration and glass filter filtration.

[0016] Furthermore, in step S3, the chemical bond activation method of the rare earth element in the leaching mother solution is to stabilize the pH value of the leaching mother solution by introducing a pH regulator to ensure the high efficiency operation of the subsequent transformation material. The pH regulator includes but is not limited to conventional agents such as hydrochloric acid, sulfuric acid, sodium hydroxide and potassium hydroxide, and the stable pH value of the mother solution is 2 to 7.

[0017] Furthermore, in step S4, the activation method of the surface functional groups of the transformation material is to wash with conventional industrial water such as pure water, soft water, tap water, etc., the activation time is 0.5 to 2 hours, the washing rate is 2 to 8 BV / h, and the activation environment temperature is 10 to 40°C; the transformation material includes but is not limited to adsorption materials with styrene, acrylic acid, phenolic acid, epoxy, vinylpyridine, urea formaldehyde, vinyl chloride as the skeleton structure and acidic groups such as sulfonic acid group, carboxylic acid group, phosphoric acid group and chelating groups such as amino acid group, aminophosphoric acid group, sulfur group as the functional group;

[0018] Furthermore, in step S5, the mother liquor rare earth element chemical bond reconstruction process refers to passing the pretreated activated mother liquor in steps S3 and S2 through the activated transformation material in step S4 at a flow rate of 1 to 10 BV / h, and the reaction environment temperature is 10 to 40°C. When the transformation material is saturated with the rare earth element, step S6 is immediately executed.

[0019] Furthermore, in step S5, the leaching agent recovery refers to directly collecting the rare earth mother liquor filtrate after the activated transformation material. In particular, the recovered leaching agent solution needs to adjust the pH to 3-5 before it can be used. Based on this, the first water circulation system of the present invention is formed: rare earth leaching mother liquor → recovery of leaching agent (liquid) → in situ leaching solution → rare earth leaching mother liquor, such as attached Figure 1 shown.

[0020] Furthermore, in step S6, the chemical bond breaking of the rare earth element of the transition material is to destroy the chemical bond formed between the surface functional group of the transition material and the rare earth element through a strong acid solution of a certain concentration. In particular, the strong acid solution includes but is not limited to hydrochloric acid, sulfuric acid, etc., the concentration is 2-15wt%, the elution time is 0.5-2h, the elution rate is 2-8BV / h, and the activation environment temperature is 10-40°C.

[0021] Furthermore, in step S6, the concentrate product recovery is carried out by subjecting the strong acid eluent (containing a high concentration of rare earth elements) to a traditional impurity removal and precipitation operation. In particular, the impurity removers include but are not limited to carbonates, bicarbonates and calcium oxide, etc., the impurity removal pH is 4.0-4.5, and the temperature is 5-40°C; the precipitants include but are not limited to carbonates, bicarbonates and organic precipitants, etc., the precipitation pH is 4.6-7.0, and the temperature is 5-40°C. Based on this, the second water circulation system described in the present invention is formed: strong acid eluent → impurity removal precipitation supernatant → mine water → strong acid eluent, as shown in the attached Figure 2 shown.

[0022] The present invention aims at the problems faced by the current on-site mining process of ionic rare earth mineral ammonium / magnesium / calcium salt single water circulation system, such as large industrial circulating water volume, high pollution risk, low leaching agent recycling efficiency, etc., and constructs a high-efficiency recovery method of rare earth and leaching agent in the leaching mother liquor based on the principle of rare earth element chemical bond reconstruction and rupture. On the one hand, the present invention utilizes the high exchange capacity of the transformation material to effectively realize the reconstruction process of the chemical bonds of the rare earth elements in the leaching mother liquor (egRe(H 2 O) n (SO 4 ) m +Mat→Mat-Re+SO 4 2- +H 2 O) to achieve efficient rare earth element enrichment; then, through the breaking process of rare earth element chemical bonds, a high concentration rare earth solution (egMat-Re+H + →+Re 3+ +Mat-H); finally, rare earth concentrate products are obtained through traditional impurity removal and precipitation process. In this process, the circulating water volume of the leaching mother liquor in the subsequent impurity removal and precipitation process can be reduced to 2% to 5%, and the rare earth element concentration can be increased by 20 to 100 times, forming an independent water circulation system. On the other hand, the present invention utilizes the efficient and rapid elution ability of the transformation material for the rare earth elements in the leaching mother liquor, which can effectively realize the separation process of rare earth elements and leaching agent (egRe(H 2 O) n(aq) +NH 4+(aq) +Mat (S) →Mat-Re (S) +NH 4+(aq) +H 2 O (aq) ). In this process, the leaching agent circulation time can be reduced to 30% to 50% of the original process time, forming another independent water circulation system. In short, the two water circulation systems for leaching agent recycling and rare earth concentrate product recovery operate independently, which can effectively reduce the pollution exposure risk of leaching agents in the mining water metallurgy stage and improve the efficiency of the ore mining stage.

[0023] The present invention has at least the following technical effects:

[0024] (1) Rare earth and leaching agent in rare earth leaching mother liquor are selectively separated to achieve efficient and synchronous recovery, which increases the concentration of rare earth mother liquor, reduces the amount of circulating water in the rare earth recovery link, and effectively shortens the leaching agent circulation time;

[0025] (2) The rare earth recovery link and the circulating leaching link form two independent water systems, which effectively avoids the mutual interference between the two links, saves the land cost of the water metallurgy workshop, and reduces the risk of leaching agent pollution exposure;

[0026] (3) A variety of precipitation processes can be used in the independent rare earth recovery process, such as oxalic acid precipitation, ammonium bicarbonate precipitation and hydroxide precipitation, which can effectively prevent industrial wastewater from the recovery process from flowing back to the mining area. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 The water circulation system 1 of the present invention;

[0028] Figure 2 This is the water circulation system 2 described in the present invention. DETAILED DESCRIPTION

[0029] In order to make the technical purpose, technical solution and technical effect of the present invention clearer, the technical solution of the present invention is clearly and completely described in combination with the embodiments below. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. In combination with the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] The weight of the relevant components mentioned in the description of the embodiments of the present invention may not only refer to the specific content of each component, but also indicate the weight ratio between the components. Therefore, as long as the content of the relevant components is proportionally enlarged or reduced according to the description of the embodiments of the present invention, it is within the scope disclosed in the description of the embodiments of the present invention. Specifically, the weight described in the description of the embodiments of the present invention may be a mass unit known in the chemical industry such as μg, mg, g, kg, etc.

[0031] Embodiment 1:

[0032] Use 3% ammonium sulfate (C (NH4+)=0.82%) leaching ionic rare earth ore to obtain rare earth leaching mother liquor, rare earth concentration is 0.5g / L, then stand for 3h for standby. Prepare a sodium polyacrylate solution with a concentration of 0.02%, add it to the leaching mother liquor at a uniform speed, flocculate and stand for 3h before filtering, and add a small amount of sulfuric acid to the filtered leaching solution, adjust the pH value of the leaching mother liquor to 4.5, and stir and activate it at 30°C for 0.5h. Fill a certain volume of amino acid-based styrene-based adsorption material into the elution column, and pass ultrapure water into the working house at a flow rate of 5BV / h to activate the adsorption material, and the activation time is 1h. After the activation of the adsorption material is completed, the leaching mother liquor is passed through the elution column at a flow rate of 10BV / h, the reaction temperature is 25°C, and the residual liquid is collected and the rare earth element concentration in the solution is detected by inductively coupled plasma-atomic emission spectroscopy (ICP-OES), and the ammonium ion concentration in the solution is detected by ion chromatograph (IC). When the adsorption bed of the elution column penetrates, the amount of solution passing through the elution column is 35BV, the time is 3.5h, the rare earth concentration of the transformation residual solution is 30mg / L, the ammonium ion concentration is 0.74%, the rare earth element recovery rate is 99.5%, and the leaching agent loss rate is 9.8%. Subsequently, the ammonium ion concentration in the transformation residual solution is supplemented to 0.82%, the leaching process is repeated and the rare earth leaching mother liquor is collected. At this time, the rare earth leaching is 95.7%. Based on this, the first independent water circulation system is formed, with a circulating water volume of 35BV and a time of 3.5h.

[0033] Subsequently, 5% hydrochloric acid was used to elute the transformation material under appropriate conditions and the hydrochloric acid eluate was collected. The eluent flow rate was 4BV / h, the eluent time was 0.5h, and the ambient temperature was 10-40°C. The concentration of rare earth elements in the eluent was detected using ICP-OES. At this time, the volume of hydrochloric acid passing through the eluent column was 2BV, the rare earth concentration was 8.7g / L, and the rare earth element elution rate was 99.4%. Finally, the rare earth concentrate was recovered by the traditional impurity removal and precipitation process. The impurity removal stage was left to stand for 1h, the precipitation stage was left to stand for 1h, and the rare earth recovery rate was 98.6%. Based on this, a second independent water circulation system was formed, with a circulating water volume of 2BV and a time consumption of 2h.

[0034] Comparative Example 1:

[0035] Use 3% ammonium sulfate (C (NH4+)=0.82%) to leach ionic rare earth ore to obtain rare earth leaching mother liquor, with a rare earth concentration of 0.5g / L, and then take the corresponding 35BV leaching mother liquor in Example 1 and let it stand for 3h for use. A sodium polyacrylate solution with a concentration of 0.02% is configured and added to the leaching mother liquor at a uniform speed. After flocculation and standing for 3h, it is filtered, and a small amount of sulfuric acid is added to the filtered leaching solution. The pH value of the leaching mother liquor is adjusted to 4.5, and it is stirred and activated at 30°C for 0.5h. Subsequently, the rare earth concentrate is directly recovered by the traditional impurity removal and precipitation process. The impurity removal stage is allowed to stand for 5h, and the precipitation stage is allowed to stand for 5h. The total rare earth recovery rate is 89.5%. Based on this, an independent water circulation system is formed, with a circulating water volume of 35BV and a time consumption of 10h.

[0036] Embodiment 2:

[0037] Use 3% ammonium sulfate (C (NH4+) =0.82%) leaching ionic rare earth ore to obtain rare earth leaching mother liquor, rare earth concentration is 0.5g / L, then stand for 3h for standby. Prepare a sodium polyacrylate solution with a concentration of 0.02%, add it to the leaching mother liquor at a uniform speed, flocculate and stand for 3h before filtering, and add a small amount of sulfuric acid to the filtered leaching solution, adjust the pH value of the leaching mother liquor to 4.5, and stir and activate it at 30°C for 0.5h. Fill a certain volume of aminophosphoryl styrene-based adsorbent into the elution column, pass ultrapure water into the working house at a flow rate of 5BV / h to activate the adsorbent material, and the activation time is 1h. After the activation of the adsorbent material is completed, the leaching mother liquor is passed through the elution column at a flow rate of 10BV / h, the reaction temperature is 25°C, and the residual liquid is collected and the rare earth element concentration in the solution is detected by inductively coupled plasma-atomic emission spectroscopy (ICP-OES), and the ammonium ion concentration in the solution is detected by ion chromatograph (IC). When the adsorption bed of the elution column penetrates, the amount of solution passing through the elution column is 32BV, the time is 3.2h, the rare earth concentration of the transformation residual solution is 30mg / L, the ammonium ion concentration is 0.72%, the rare earth element recovery rate is 97.1%, and the leaching agent loss rate is 12.2%. Subsequently, the ammonium ion concentration in the transformation residual solution is supplemented to 0.82%, the leaching process is repeated and the rare earth leaching mother liquor is collected. At this time, the rare earth leaching is 91.2%. Based on this, the first independent water circulation system is formed, with a circulating water volume of 32BV and a time of 3.2h.

[0038] Subsequently, 5% hydrochloric acid was used to elute the transformation material under appropriate conditions and the hydrochloric acid eluate was collected. The eluent flow rate was 4BV / h, the eluent time was 0.5h, and the ambient temperature was 10-40°C. The concentration of rare earth elements in the eluent was detected using ICP-OES. At this time, the volume of hydrochloric acid passing through the eluent column was 2BV, the rare earth concentration was 8.0g / L, and the rare earth element elution rate was 98.1%. Finally, the rare earth concentrate was recovered by the traditional impurity removal and precipitation process. The impurity removal stage was left to stand for 1h, the precipitation stage was left to stand for 1h, and the rare earth recovery rate was 96.6%. Based on this, a second independent water circulation system was formed, with a circulating water volume of 2BV and a time consumption of 2h.

[0039] Embodiment 3:

[0040] Use 5% magnesium sulfate (C (Mg2+) =1.0%) to leach ionic rare earth ore to obtain rare earth leaching mother liquor, with a rare earth concentration of 0.5g / L, and then stand for 3h for standby. Prepare a sodium polyacrylate solution with a concentration of 0.02%, add it to the leaching mother liquor at a uniform speed, flocculate and stand for 3h, then filter, and add a small amount of sulfuric acid to the filtered leaching solution, adjust the pH value of the leaching mother liquor to 4.5, and stir and activate it at 30°C for 0.5h. Fill a certain volume of amino acid-based styrene-based adsorption material into the elution column, and pass ultrapure water into the working house at a flow rate of 5BV / h to activate the adsorption material, and the activation time is 1h. After the activation of the adsorption material is completed, the leaching mother liquor is passed through the elution column at a flow rate of 10BV / h, the reaction temperature is 25°C, and the residual liquid is collected and the concentration of rare earth elements and magnesium ions in the solution is detected using inductively coupled plasma-atomic emission spectroscopy (ICP-OES). When the adsorption bed of the elution column penetrates, the elution column now passes 30BV of solution, takes 3h, the rare earth concentration of the transition residual solution is 30mg / L, the magnesium ion concentration is 0.88%, the rare earth element recovery rate is 98.1%, and the leaching agent loss rate is 12%. Subsequently, the magnesium ion concentration in the transition residual solution is supplemented to 1.0%, the leaching process is repeated and the rare earth leaching mother liquor is collected. At this time, the rare earth leaching is 92.1%. Based on this, the first independent water circulation system is formed, with a circulating water volume of 30BV and a time of 3.0h.

[0041] Subsequently, 5% hydrochloric acid was used to elute the transformation material under appropriate conditions and the hydrochloric acid eluate was collected. The eluent flow rate was 4BV / h, the eluent time was 0.5h, and the ambient temperature was 10-40°C. The concentration of rare earth elements in the eluent was detected using ICP-OES. At this time, the volume of hydrochloric acid passing through the eluent column was 2BV, the rare earth concentration was 7.5g / L, and the rare earth element elution rate was 99.2%. Finally, the rare earth concentrate was recovered by the traditional impurity removal and precipitation process. The impurity removal stage was left to stand for 1h, the precipitation stage was left to stand for 1h, and the rare earth recovery rate was 98.6%. Based on this, a second independent water circulation system was formed, with a circulating water volume of 2BV and a time consumption of 2h.

[0042] Embodiment 4:

[0043] Use 5% calcium chloride (C (Ca2+) =1.8%) to leach ionic rare earth ore to obtain rare earth leaching mother liquor, with a rare earth concentration of 0.5g / L, and then stand for 3h for standby. Prepare a sodium polyacrylate solution with a concentration of 0.02%, add it to the leaching mother liquor at a uniform speed, flocculate and stand for 3h before filtering, and add a small amount of sulfuric acid to the filtered leaching solution, adjust the pH value of the leaching mother liquor to 4.5, and stir and activate it at 30°C for 0.5h. Fill a certain volume of amino acid-based styrene-based adsorption material into the elution column, and pass ultrapure water into the working house at a flow rate of 5BV / h to activate the adsorption material, and the activation time is 1h. After the activation of the adsorption material is completed, the leaching mother liquor is passed through the elution column at a flow rate of 10BV / h, the reaction temperature is 25°C, and the residual liquid is collected and the concentration of rare earth elements and calcium ions in the solution is detected using inductively coupled plasma-atomic emission spectroscopy (ICP-OES). When the adsorption bed of the elution column penetrates, the elution column now passes 20BV of solution, takes 2h, the rare earth concentration of the transition residual solution is 30mg / L, the calcium ion concentration is 1.5%, the rare earth element recovery rate is 92.3%, and the leaching agent loss rate is 16.7%. Subsequently, the calcium ion concentration in the transition residual solution is supplemented to 1.8%, the leaching process is repeated and the rare earth leaching mother liquor is collected. At this time, the rare earth leaching is 89.4%. Based on this, the first independent water circulation system is formed, with a circulating water volume of 20BV and a time of 2h.

[0044] Subsequently, 5% hydrochloric acid was used to elute the transformation material under appropriate conditions and the hydrochloric acid eluate was collected. The eluent flow rate was 4BV / h, the eluent time was 0.5h, and the ambient temperature was 10-40°C. The concentration of rare earth elements in the eluent was detected using ICP-OES. At this time, the volume of hydrochloric acid passing through the eluent column was 2BV, the rare earth concentration was 5.0g / L, and the rare earth element elution rate was 98.1%. Finally, the rare earth concentrate was recovered by the traditional impurity removal and precipitation process. The impurity removal stage was left to stand for 1h, the precipitation stage was left to stand for 1h, and the rare earth recovery rate was 95.6%. Based on this, a second independent water circulation system was formed, with a circulating water volume of 2BV and a time consumption of 2h.

[0045] Embodiment 5:

[0046] Use 3% ammonium sulfate (C (NH4+)=0.82%) to leach ionic rare earth ore to obtain rare earth leaching mother liquor, with a rare earth concentration of 0.5g / L, and then stand for 3h for standby. Prepare a sodium polyacrylate solution with a concentration of 0.02%, add it to the leaching mother liquor at a uniform speed, flocculate and stand for 3h, then filter, and add a small amount of sulfuric acid to the filtered leaching solution, adjust the pH value of the leaching mother liquor to 4.5, and stir and activate it at 30°C for 0.5h. Fill a certain volume of sulfonic acid styrene-based adsorbent material into the elution column, and pass ultrapure water into the working house at a flow rate of 5BV / h to activate the adsorbent material, and the activation time is 1h. After the activation of the adsorbent material is completed, the leaching mother liquor is passed through the elution column at a flow rate of 10BV / h, the reaction temperature is 25°C, and the residual liquid is collected and the rare earth element concentration in the solution is detected by inductively coupled plasma-atomic emission spectroscopy (ICP-OES), and the ammonium ion concentration in the solution is detected by ion chromatograph (IC). When the adsorption bed of the elution column penetrates, the amount of solution passing through the elution column is 20BV, the time is 2h, the rare earth concentration of the transformation residual solution is 30mg / L, the ammonium ion concentration is 0.70%, the rare earth element recovery rate is 96.1%, and the leaching agent loss rate is 12.2%. Subsequently, the ammonium ion concentration in the transformation residual solution is supplemented to 0.82%, the leaching process is repeated and the rare earth leaching mother liquor is collected. At this time, the rare earth leaching is 97.3%. Based on this, the first independent water circulation system is formed, with a circulating water volume of 20BV and a time of 2h.

[0047] Subsequently, 5% hydrochloric acid was used to elute the transformation material under appropriate conditions and the hydrochloric acid eluate was collected. The eluent flow rate was 4BV / h, the eluent time was 0.5h, and the ambient temperature was 10-40°C. The concentration of rare earth elements in the eluent was detected using ICP-OES. At this time, the volume of hydrochloric acid passing through the eluent column was 2BV, the rare earth concentration was 5.0g / L, and the rare earth element elution rate was 93.1%. Finally, the rare earth concentrate was recovered by the traditional impurity removal and precipitation process. The impurity removal stage was left to stand for 1h, the precipitation stage was left to stand for 1h, and the rare earth recovery rate was 97.7%. Based on this, a second independent water circulation system was formed, with a circulating water volume of 2BV and a time consumption of 2h.

[0048] Embodiment 6:

[0049] Use 3% ammonium sulfate (C (NH4+)=0.82%) leaching ionic rare earth ore to obtain rare earth leaching mother liquor, rare earth concentration is 0.5g / L, then stand for 3h for standby. Prepare a sodium polyacrylate solution with a concentration of 0.02%, add it to the leaching mother liquor at a uniform speed, flocculate and stand for 3h before filtering, and add a small amount of sulfuric acid to the filtered leaching solution, adjust the pH value of the leaching mother liquor to 4.5, and stir and activate it at 30°C for 0.5h. Fill a certain volume of carboxylic acid-based styrene-based adsorbent material into the elution column, and pass ultrapure water into the working house at a flow rate of 5BV / h to activate the adsorbent material, and the activation time is 1h. After the activation of the adsorbent material is completed, the leaching mother liquor is passed through the elution column at a flow rate of 10BV / h, the reaction temperature is 25°C, and the residual liquid is collected and the rare earth element concentration in the solution is detected by inductively coupled plasma-atomic emission spectroscopy (ICP-OES), and the ammonium ion concentration in the solution is detected by ion chromatograph (IC). When the adsorption bed of the elution column penetrates, the amount of solution passing through the elution column is 28BV, the time is 2.8h, the rare earth concentration of the transition residual solution is 30mg / L, the ammonium ion concentration is 0.72%, the rare earth element recovery rate is 94.2%, and the leaching agent loss rate is 12.2%. Subsequently, the ammonium ion concentration in the transition residual solution is supplemented to 0.82%, the leaching process is repeated and the rare earth leaching mother liquor is collected. At this time, the rare earth leaching is 91.9%. Based on this, the first independent water circulation system is formed, with a circulating water volume of 28BV and a time of 2.8h.

[0050] Subsequently, 5% hydrochloric acid was used to elute the transformation material under appropriate conditions and the hydrochloric acid eluate was collected. The eluent flow rate was 4BV / h, the eluent time was 0.5h, and the ambient temperature was 10-40°C. The concentration of rare earth elements in the eluent was detected using ICP-OES. At this time, the volume of hydrochloric acid passing through the eluent column was 2BV, the rare earth concentration was 7.0g / L, and the rare earth element elution rate was 98.1%. Finally, the rare earth concentrate was recovered by the traditional impurity removal and precipitation process. The impurity removal stage was left to stand for 1h, the precipitation stage was left to stand for 1h, and the rare earth recovery rate was 97.9%. Based on this, a second independent water circulation system was formed, with a circulating water volume of 2BV and a time consumption of 2h.

[0051] Embodiment 7:

[0052] Use 3% ammonium sulfate (C (NH4+)=0.82%) to leach ionic rare earth ore to obtain rare earth leaching mother liquor, with a rare earth concentration of 0.5g / L, and then stand for 3h for standby. Prepare a sodium polyacrylate solution with a concentration of 0.02%, add it to the leaching mother liquor at a uniform speed, flocculate and stand for 3h, then filter, and add a small amount of sulfuric acid to the filtered leaching solution, adjust the pH value of the leaching mother liquor to 4.5, and stir and activate it at 30°C for 0.5h. Fill a certain volume of phosphate-based styrene-based adsorbent material into the elution column, and pass ultrapure water into the working house at a flow rate of 5BV / h to activate the adsorbent material, and the activation time is 1h. After the activation of the adsorbent material is completed, the leaching mother liquor is passed through the elution column at a flow rate of 10BV / h, the reaction temperature is 25°C, and the residual liquid is collected and the rare earth element concentration in the solution is detected by inductively coupled plasma-atomic emission spectroscopy (ICP-OES), and the ammonium ion concentration in the solution is detected by ion chromatograph (IC). When the adsorption bed of the elution column penetrates, the amount of solution passing through the elution column is 25BV, the time is 2.5h, the rare earth concentration of the transition residual solution is 30mg / L, the ammonium ion concentration is 0.69%, the rare earth element recovery rate is 92.7%, and the leaching agent loss rate is 15.6%. Subsequently, the ammonium ion concentration in the transition residual solution is supplemented to 0.82%, the leaching process is repeated and the rare earth leaching mother liquor is collected. At this time, the rare earth leaching is 93.7%. Based on this, the first independent water circulation system is formed, with a circulating water volume of 25BV and a time of 2.5h.

[0053] Subsequently, 5% hydrochloric acid was used to elute the transformation material under appropriate conditions and the hydrochloric acid eluate was collected. The eluent flow rate was 4BV / h, the eluent time was 0.5h, and the ambient temperature was 10-40°C. The concentration of rare earth elements in the eluent was detected using ICP-OES. At this time, the volume of hydrochloric acid passing through the eluent column was 2BV, the rare earth concentration was 6.25g / L, and the rare earth element elution rate was 94.4%. Finally, the rare earth concentrate was recovered by the traditional impurity removal and precipitation process. The impurity removal stage was left to stand for 1h, the precipitation stage was left to stand for 1h, and the rare earth recovery rate was 93.1%. Based on this, a second independent water circulation system was formed, with a circulating water volume of 2BV and a time consumption of 2h.

[0054] The above is an explanation of the embodiments of the present invention. However, the present invention is not limited to the above embodiments. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for efficiently recovering rare earth and leaching agent from ionic rare earth ore leaching mother liquor, comprising the following steps: S1. Obtaining ion adsorption type rare earth ore leaching mother liquor; S2, the leaching mother liquor is pre-treated by sedimentation, flocculation and filtration to obtain a pre-treated mother liquor; S3, adding a small amount of pH regulator to the pre-treated mother liquor for activation to obtain an activated mother liquor; S4, activating the surface functional groups of the transformation material to obtain an activated transformation material; S5, reconstructing the chemical bonds of the rare earth elements in the activated mother solution and recovering the leaching agent; S6. Breaking of chemical bonds of rare earth elements in transitional materials and recovery of rare earth concentrate products.

2. The efficient recovery method according to claim 1, wherein: The ionic rare earth ore leaching mother liquor in step S1 is the leaching mother liquor obtained by the cation exchange leaching process.

3. The efficient recovery method according to claim 2, wherein: The cations include ammonium ions, magnesium ions, calcium ions and aluminum ions.

4. The efficient recovery method according to claim 1, wherein: The sedimentation time in step S2 is 2 to 5 hours; The flocculants used in the flocculation process include sodium polyacrylate, dimethyl diallyl ammonium chloride and polyacrylamide; the flocculation time is 2 to 5 hours; The filtering methods include bag filtering, multi-media filtering and glass filter material filtering.

5. The efficient recovery method according to claim 1, wherein: The pH adjusting agent in step S3 includes: hydrochloric acid, sulfuric acid, sodium hydroxide and potassium hydroxide; The pH adjuster adjusts the pH value of the mother solution to 2-7.

6. The efficient recovery method according to claim 1, wherein: Step S4: Activating the surface functional groups of the transformation material by eluting with industrial water for 0.5 to 2 hours, at a elution rate of 2 to 8 BV / h, and at an activation ambient temperature of 10 to 40°C; The transformation material includes: adsorption materials with styrene, acrylic acid, phenolic acid, epoxy, vinylpyridine, urea-formaldehyde, vinyl chloride as skeleton structure, sulfonic acid group, carboxylic acid group, phosphoric acid group as acidic group and amino acid group, aminophosphoric acid group, sulfur group as functional group.

7. The efficient recovery method according to claim 1, wherein: The step S5 of reconstructing the chemical bonds of the rare earth elements in the activated mother solution comprises: The activated mother solution is passed through the activated transformation material at a flow rate of 1 to 10 BV / h, and the reaction environment temperature is 10 to 40° C. When the transformation material is saturated with the rare earth element, step S6 is immediately performed.

8. The efficient recovery method according to claim 1, wherein: The step S5 of recovering the leaching agent comprises: directly collecting the rare earth mother liquor filtrate after the activated transformation material; The pH of the recovered leaching agent needs to be adjusted to 3-5.

9. The efficient recovery method according to claim 1, wherein: In step S6, the breaking of the chemical bonds of the rare earth elements in the transformation material includes: eluting the transformation material with a strong acid at a concentration of 2 to 15 wt% to destroy the chemical bonds formed between the surface functional groups of the transformation material and the rare earth elements, the elution time is 0.5 to 2 h, the elution rate is 2 to 8 BV / h, and the activation environment temperature is 10 to 40°C.

10. The efficient recovery method according to claim 1, wherein: The concentrate product recovery in step S6 includes: removing impurities and precipitating the strong acid washing solution; Impurity removers include: carbonate, bicarbonate and calcium oxide; the impurity removal pH is 4.0-4.5, and the temperature is 5-40°C; The precipitants include carbonates, bicarbonates and organic precipitants; the precipitation pH is 4.6-7.0 and the temperature is 5-40°C.

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