Application method of modified resin in adsorption of gallium in acidic system

Abstract

The invention relates to an application method of modified resin in adsorption of gallium in an acid system, belongs to the technical field of separation and extraction of rare metals, and solves one of the problems of small resin adsorption capacity, poor selectivity and the like in the existing gallium extraction process of a resin adsorption method. Comprising the following steps: adsorption: mixing modified resin with an acidic gallium-containing solution, carrying out adsorption treatment, and then carrying out solid-liquid separation to obtain gallium-loaded saturated modified resin; desorption: mixing the saturated modified resin with a hydrochloric acid aqueous solution to desorb gallium ions from the modified resin, and after desorption is completed, carrying out solid-liquid separation to obtain regenerated modified resin and a gallium-containing desorption solution; the modified resin is resin obtained by introducing at least one functional group of carboxyl, sulfonic acid group, amide group or phosphate group to a macroporous resin skeleton with weakly alkaline active sites through grafting reaction. The adsorption capacity of gallium in an acid system is large.

Description

Technical Field

[0001] This invention relates to the field of rare metal separation and extraction technology, and in particular to a method for applying modified resin to adsorb gallium in an acidic system. Background Technology

[0002] Gallium is an important strategic rare metal with wide applications in semiconductors, optoelectronic materials, and advanced alloys. Due to its extremely low crustal abundance and highly dispersed occurrence (in minerals such as lead-zinc ore, bauxite, and coal gangue), efficient and economical recovery of gallium from complex industrial leachates or wastewaters is extremely challenging.

[0003] Currently, the main technologies for recovering gallium from acidic media include solvent extraction, chemical precipitation, and ion exchange / adsorption. While solvent extraction offers good selectivity, it is complex, requires large amounts of volatile organic solvents, poses safety and environmental risks, and places high demands on equipment for phase separation. Chemical precipitation is simple to operate, but suffers from poor selectivity, easily introduces impurities, has limited recovery rates for low-concentration gallium solutions, and generates difficult-to-treat precipitated sludge. Ion exchange / adsorption, on the other hand, has attracted significant attention due to its ease of operation, environmental friendliness, ability to treat low-concentration solutions, and regenerable resin.

[0004] However, conventional ion exchange resins used in acidic systems (such as strong acid cation exchange resins) are ineffective against Ga... 3+ The selectivity is generally not high, especially in areas rich in Al3+ and Fe. 3+ Zn 2+ In complex leachates containing competing ions, these ions can severely occupy resin exchange sites, leading to a significant decrease in gallium adsorption capacity and purity. Optimizing the adsorption-desorption process to fully utilize the resin's maximum efficiency (including high adsorption capacity, high selectivity, fast kinetics, and excellent cycling stability) in real-world acidic and complex systems is a pressing issue for rare metal separation and extraction. Existing process parameters often lack systematic optimization or fail to adequately consider the synergistic effects between parameters, resulting in low resin adsorption capacity.

[0005] Therefore, optimizing the application method of adsorbing gallium with resin in acidic systems to achieve efficient and selective separation and enrichment of gallium from complex acidic solutions has important industrial application value. Summary of the Invention

[0006] Based on the above analysis, the present invention aims to provide a method for applying modified resin to adsorb gallium in an acidic system, in order to solve at least one of the problems of existing methods for adsorbing gallium in acidic systems, such as small adsorption capacity and poor selectivity.

[0007] The objective of this invention is mainly achieved through the following technical solutions:

[0008] This invention provides a method for applying modified resin to adsorb gallium in an acidic system, comprising the following steps:

[0009] S1: Adsorption, the modified resin is mixed with an acidic gallium-containing solution for adsorption treatment, followed by solid-liquid separation to obtain gallium-loaded saturated modified resin.

[0010] S2: Desorption. The saturated modified resin is mixed with hydrochloric acid aqueous solution to desorb gallium ions from the modified resin. After desorption is completed, solid-liquid separation is performed to obtain regenerated modified resin and gallium-containing desorption solution.

[0011] The modified resin is a resin in which at least one functional group, consisting of a carboxyl group, a sulfonic acid group, an amide group, or a phosphate group, is introduced onto a macroporous resin skeleton with weakly basic active sites through a grafting reaction.

[0012] Furthermore, the pH value of the acidic gallium-containing solution is 1-5.

[0013] Further, in step S1, the mass-to-volume ratio of the modified resin to the acidic gallium-containing solution is (0.01-0.05) g: 60 mL.

[0014] Furthermore, in step S1, the adsorption temperature is 30-60℃.

[0015] Furthermore, in step S1, the adsorption treatment time is 8-36 hours.

[0016] Further, in step S2, the concentration of the hydrochloric acid aqueous solution is 0.1-2 mol / L.

[0017] Further, in step S2, the mass-to-volume ratio of the saturated modified resin to the hydrochloric acid aqueous solution is (0.01-0.05) g: 10 mL.

[0018] Furthermore, in step S2, the desorption temperature is 30-60℃.

[0019] Furthermore, in step S2, the desorption process takes 0.5-8 hours.

[0020] The present invention also provides a method for preparing a modified resin for adsorbing gallium in an acidic system, which is applicable to the above-mentioned application methods.

[0021] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0022] 1. This invention combines optimized application processes with modified resins of specific structures, targeting Ga in complex acidic systems. 3+The adsorption and desorption processes were dually optimized; the parameters such as pH range, temperature, time, and liquid-solid ratio worked synergistically to effectively suppress Al3+ and Fe. 3+ It ensures high adsorption capacity of gallium while co-adsorbing the main competing ions.

[0023] 2. This invention achieves efficient desorption while minimizing chemical and thermal damage to the modified resin structure through the synergistic effect of parameters such as pH range, temperature, time, and liquid-solid ratio, thus ensuring the excellent recyclability of the resin (adsorption capacity retention rate ≥86% after 5 cycles).

[0024] 3. The application method provided by this invention has clear steps and well-defined parameters, making it easy to implement and control in industrial settings. This method is not only suitable for laboratory-scale gallium extraction but also provides a direct and reliable technical solution for the design and operation of industrial gallium recovery devices based on high-performance modified resins in acidic systems. This method is particularly suitable for processing complex acidic leachates (such as coal-based gallium resource leachates), achieving efficient gallium enrichment and high desorption solution concentration, which is beneficial for subsequent electrolysis and other processes, thus improving the overall efficiency of resource recovery.

[0025] 4. This invention selects a macroporous weakly basic resin as the base resin. The macroporous characteristics endow it with a high specific surface area and mass transfer efficiency, which is beneficial for the diffusion and adsorption of target ions within the pores. Furthermore, the macroporous structure is not easily collapsed in strongly acidic media, maintaining the mechanical stability of the resin and making it highly compatible with the acid leaching process for gallium extraction from coal-based gallium resources. The functional groups on its surface, acting as weakly basic active sites, can be selectively replaced by specific functional groups (such as carboxyl groups and sulfonic acid groups) through free radical polymerization, thereby achieving directional regulation of the resin surface chemical properties and enhancing the resin's ability to attract gallium ions (Ga). 3+ It has an affinity for aluminum (Al) while inhibiting its absorption by aluminum (Al). 3+ ), iron (Fe) 3+ The interference of competing ions such as gallium ions significantly improves the adsorption selectivity of gallium ions in acidic solutions.

[0026] 5. This invention significantly increases the number of effective chelating sites per unit volume or their surface charge by high-density grafting of highly electronegative heteroatom polar functional groups onto a macroporous resin framework, thereby improving the total exchange capacity of the modified resin and its selective adsorption capacity for gallium ions. The modified resin prepared by this invention has characteristics such as high stability, high adsorption capacity and long service life.

[0027] 6. This invention, by synergistically introducing two or more different functional groups onto a macroporous resin framework, exhibits stronger adsorption performance compared to single-ligand resins: different functional groups form a multidentate synergistic effect through complementary coordination characteristics, which can construct a more stable metal ion coordination structure, making its adsorption capacity higher than that of single-ligand resins and substrate resins; at the same time, the dual-group system can more accurately identify gallium ions through synergistic screening of steric hindrance effect and charge matching, and significantly enhances the repulsion of interfering ions; this dual-functional synergistic mechanism enables the modified resin to maintain excellent adsorption performance in complex solution systems.

[0028] 7. By optimizing the resin modification process parameters, including the amount of modified monomer, the amount of initiator, the reaction temperature, the reaction time, and the proportion of various modified monomers, this invention significantly improves the grafting rate of functional groups, enabling the modified resin to have both higher total exchange capacity and specific adsorption capacity for gallium ions.

[0029] In this invention, the above-described technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of this invention will be set forth in the following description, and some advantages may become apparent from the description or be learned by practicing the invention. The objects and other advantages of this invention can be realized and obtained from what is particularly pointed out in the description and drawings. Attached Figure Description

[0030] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0031] Figure 1 This is a schematic diagram of the synthetic route and adsorption process for preparing carboxyl-modified resins using acrylic acid as a modifying monomer in Examples 1-5;

[0032] Figure 2 This is a schematic diagram of the synthetic route and adsorption process for preparing sulfonic acid-modified resins using AMPS as the modified monomer in Examples 6-10.

[0033] Figure 3 The above are schematic diagrams of the synthetic routes and adsorption processes for preparing multi-ligand chelate modified resins using acrylic acid and AMPS as modified monomers in Examples 11-16.

[0034] Figure 4 The graph shows the change in gallium adsorption capacity of the modified resin used in Example 13 during 5 adsorption-desorption cycles. Detailed Implementation

[0035] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0036] This invention provides an application of modified resin in adsorbing gallium in an acidic system, the specific process of which is as follows:

[0037] S1: Adsorption, the modified resin is mixed with an acidic gallium-containing solution for adsorption treatment, followed by solid-liquid separation to obtain gallium-loaded saturated modified resin.

[0038] S2: Desorption. The saturated modified resin is mixed with hydrochloric acid aqueous solution to desorb gallium ions from the modified resin. After desorption is completed, solid-liquid separation is performed to obtain regenerated modified resin and gallium-containing desorption solution.

[0039] The modified resin is a resin in which at least one functional group, consisting of a carboxyl group, a sulfonic acid group, an amide group, or a phosphate group, is introduced onto a macroporous resin skeleton with weakly basic active sites through a grafting reaction.

[0040] Specifically, in step S1, the pH value of the acidic gallium-containing solution is 1-5; this pH range is the acidic environment in which the modified resin of the present invention exhibits optimal adsorption performance. When the pH value is too low (<1), the H in the solution... + Too high a concentration will react with Ga 3+ Strong competition for active sites on the resin severely inhibits the adsorption of gallium ions; excessively high pH values ​​(>5, close to neutral or weakly acidic) also hinder the adsorption of gallium ions. 3+ Hydrolysis may begin to form precipitates or hydroxyl complexes, affecting their ionic form and adsorption. On the other hand, impurity ions in the solution (such as Al) 3+ Fe 3+ The behavior of [the system] is also more complex, which may reduce selectivity.

[0041] The mass-to-volume ratio of the modified resin to the acidic gallium-containing solution is (0.01-0.05) g: 60 mL. This ratio range ensures that the resin adsorption sites and the gallium ion concentration in the solution reach equilibrium during the adsorption process. If the ratio is too low (too little resin), the limited adsorption sites cannot fully adsorb gallium in the solution, resulting in a high adsorption capacity but a low total adsorption amount and poor solution treatment capacity. If the ratio is too high (too much resin), although complete adsorption can be ensured, the adsorption capacity per unit mass of resin (mg / g) will be poor due to "excess sites," which is uneconomical and may affect mass transfer due to resin accumulation.

[0042] The adsorption temperature is 30-60℃. During adsorption, stirring or shaking is used to ensure sufficient contact between the modified resin and the acidic gallium-containing solution. Excessive adsorption temperature can lead to desorption of adsorbed gallium ions and may also damage the functional groups on the resin surface, reducing the adsorption capacity. Conversely, excessively low temperatures slow down molecular diffusion, resulting in insufficient contact between the resin and gallium ions and affecting adsorption efficiency. Furthermore, mechanical stirring or shaking can break the static boundary layer between the liquid and solid phases, enhancing the convective mass transfer of gallium ions from the solution to the resin particle surface and promoting uniform dispersion of resin particles in the solution. This prevents sedimentation or agglomeration, ensuring that all adsorption sites are fully exposed and in contact with the target ions, thereby significantly improving the adsorption rate and overall adsorption efficiency.

[0043] The adsorption treatment time is 8-36 hours. If the time is too short (<8 hours), the adsorption reaction will not be fully carried out, and the resin will not reach its saturation adsorption capacity, resulting in insufficient utilization. If the time is too long (>36 hours), it will be far beyond the time required to reach equilibrium for most systems. In industrial applications, this means low equipment utilization, long cycle time, poor economic efficiency, and prolonged stirring may increase the mechanical wear of the resin.

[0044] Specifically, in step S2, the concentration of the hydrochloric acid aqueous solution is 0.1-2 mol / L. If the acid concentration is too low, gallium ions cannot be effectively desorbed, while if it is too high, the resin molecular structure will be damaged and its service life will be shortened.

[0045] The mass-to-volume ratio of saturated modified resin to hydrochloric acid aqueous solution is (0.01-0.05) g: 10 mL. If the ratio is too high (i.e., the resin mass is too high relative to 10 mL of hydrochloric acid aqueous solution, for example, exceeding 0.05 g), too many adsorption sites need to be treated per unit volume of hydrochloric acid aqueous solution, thus providing too much H₂. + The total amount may not be sufficient to completely replace all adsorbed gallium ions, resulting in residual desorption and incomplete regeneration. At the same time, resin particles tend to accumulate under high solid content, causing localized mass transfer problems and possible "localized over-acidity" points, which exacerbates the damage to the resin. If the ratio is too low (i.e., the resin mass is too low relative to 10 mL of hydrochloric acid aqueous solution, for example, less than 0.01 g), although it can ensure complete desorption, it will lead to a significant dilution of the gallium concentration in the hydrochloric acid aqueous solution, increasing the load and cost of subsequent enrichment or electrolysis processes, while generating more waste acid liquid per unit of resin, reducing the economic efficiency and environmental friendliness of the process.

[0046] The desorption temperature is 30-60℃. Within this temperature range, the process of ion exchange / coordination bond breaking can be accelerated while avoiding the risks associated with excessively high temperatures. If the temperature is too high (>60℃), the corrosive and destructive effect of hydrochloric acid on the resin structure will be aggravated. At the same time, the already desorbed gallium ions may undergo unfavorable re-adsorption or hydrolysis side reactions under thermal disturbance. If the temperature is too low (<30℃), the molecular thermal motion is insufficient, the desorption reaction rate is slow, and it takes longer to achieve the same desorption rate, thus reducing the process efficiency.

[0047] The desorption time is 0.5-8h. If the time is too short (<0.5h), the desorption reaction may only occur on the surface or in the shallow layer of the resin, and the gallium ions adsorbed in the internal channels may not be completely removed, resulting in incomplete resin regeneration and a significant reduction in the adsorption capacity of the next cycle. If the time is too long (>8h), it prolongs the exposure time of the resin in the strong acid environment and increases the risk of structural damage.

[0048] During desorption, stirring or shaking can promote full contact between the saturated modified resin and the hydrochloric acid aqueous solution. Similar to the adsorption process, stirring or shaking can enhance the H+ desorption process. + Mass transfer from the bulk solution to the active sites inside the resin particles, and ensuring the desorption of products (Ga 3+ It can quickly leave the resin surface and diffuse into the bulk solution, breaking the local equilibrium, promoting continuous desorption, improving the desorption rate and completeness, and avoiding desorption dead zones caused by resin agglomeration.

[0049] It should be noted that metallic gallium can be further extracted from the gallium-containing desorption solution by electrolysis.

[0050] It should be noted that the above-mentioned modified resin was prepared by the following method, the steps of which are as follows:

[0051] S1: Clean the base resin, wherein the base resin is a macroporous resin with weakly basic active sites.

[0052] S2: Mix the cleaned base resin and the modifier aqueous solution to obtain a mixture. Inert gas is introduced into the reaction vessel, and then the initiator is added to the mixture. Stirring causes a grafting reaction. Inert gas is continuously introduced during the reaction. After the reaction is terminated, solid-liquid separation is performed to obtain wet modified resin.

[0053] S3: The wet modified resin obtained in S2 is washed, filtered, and vacuum dried to obtain the finished modified resin.

[0054] Specifically, in step S1, the base resin is a macroporous resin with weakly basic active sites, including one of D301, D304, D306, D307, 303X2 (704), D301A (701A), 710B, and 709.

[0055] The macroporous nature of the substrate resin endows it with a high specific surface area and mass transfer efficiency, which is beneficial for the diffusion and adsorption of target ions within the pores. Furthermore, the macroporous structure is not easily collapsed in strongly acidic media, maintaining the resin's mechanical stability and making it highly compatible with the acid leaching process for gallium extraction from coal-based gallium resources. The surface groups, acting as weakly basic active sites, can be selectively replaced by specific functional groups (such as carboxyl and sulfonic acid groups) through free radical polymerization, thereby achieving directional regulation of the resin's surface chemical properties and enhancing the resin's ability to attract gallium ions (Ga). 3+ It has an affinity for aluminum (Al) while inhibiting its absorption by aluminum (Al). 3+ ), iron (Fe) 3+ Interference from competing ions such as ions.

[0056] Specifically, in step S1, the cleaning of the base resin to remove unpolymerized monomers and impurities in the pores on the surface of the base resin is carried out by: adding excess deionized water to the base resin and stirring and cleaning; after cleaning, vacuum filtration to remove water, and repeating the stirring and cleaning-vacuum filtration process 3 times; and vacuum drying the treated resin to constant weight.

[0057] During the stirring and cleaning process, the stirring speed is 400-800 rpm and the cleaning time is 3-10 minutes.

[0058] The temperature for vacuum drying is 50-65℃. Too high a temperature will damage the resin skeleton, while too low a temperature will result in excessively long drying time or insufficient drying of the resin, affecting subsequent reactions.

[0059] Specifically, in step S2, the solute in the modified agent aqueous solution contains carboxyl groups (-COOH), sulfonic acid groups (-SO3H), amide groups (-CONH2), and phosphate groups (-PO3). - The monomeric substances are selected from one or a combination of two of the monomeric substances; preferably, the monomeric substances are selected from compounds containing the above-mentioned functional groups, including but not limited to acrylic acid, fumaric acid, acryloyloxyethyl phosphate, 2-acrylamido-2-methylpropanesulfonic acid (AMPS), and acrylamide; that is, the monomeric substances contain polar functional groups with highly electronegative heteroatoms (O or N), including carboxyl groups (-COOH) and phosphate groups (-PO3). - ), sulfonic acid groups (-SO3H), and amide groups (-CONH2) can exist stably under acidic conditions and interact with metal ions / polar molecules through lone pairs of electrons or dissociation.

[0060] For example, when the monomer contains a carboxyl group, the modifier aqueous solution is prepared by mixing the monomer with NaOH in deionized water and adjusting the pH to 7.0±0.2; in one possible design, the monomer is acrylic acid, and the modifier aqueous solution is prepared by mixing acrylic acid, NaOH, and deionized water in a certain proportion to obtain a sodium acrylate solution with a pH of 7.0±0.2.

[0061] The mass concentration (i.e., solute concentration) of the monomer in the aqueous solution of the modifier is 10%-30%. When the solute concentration is less than 10%, there are fewer graftable monomer molecules, fewer functional groups to be grafted onto the surface, and a low resin grafting rate, which affects the resin adsorption performance. When the solute concentration is higher than 30%, the excess monomer will promote homogeneous nucleation and form micelles. The initiator free radicals preferentially initiate homopolymerization, forming densely grafted short chains, which leads to the covering of surface active sites and hinders subsequent monomer diffusion.

[0062] Specifically, in step S2, the initiator is one of ammonium persulfate (APS), benzoyl peroxide, or azobisisobutyronitrile; the amount of initiator is 0.2wt%-2wt% of the total mass of monomers in the modifier aqueous solution. It should be noted that the amount of initiator directly affects the formation of grafting sites and the growth of grafted chains. If the amount of initiator is too small, there will be insufficient free radicals generated in the system, which will not be able to form enough grafting sites, resulting in low grafting efficiency. If the amount of initiator is too large, excessive free radicals will be generated, resulting in the formation of a large amount of homopolymer, which will compete with the grafted chains for monomers and trigger chain termination reactions, reducing the effective chain length. In addition, the initiator residues may also attack the already grafted polymer chains, causing the grafting sites to break and reducing the grafting rate.

[0063] Specifically, in step S2, the reaction temperature of the stirring reaction is controlled at 30-65℃, and the stirring speed is within the range of 300-1000 rpm to ensure that the grafting reaction proceeds. When the reaction temperature is low, the initiator decomposes and the molecular diffusion rate is slow, which will limit the generation rate of grafting sites and the diffusion rate of monomers, resulting in a low grafting rate of the base resin. If the reaction temperature is too high, on the one hand, it is easy to damage the resin structure, and on the other hand, it is easy to trigger homopolymerization and chain termination reactions, affecting the grafting effect of functional monomers on the surface of the base resin.

[0064] It should be noted that the reaction process in step S2 is carried out under an inert atmosphere. Specifically, after adding the modifier solution and before adding the initiator, an inert gas (exemplarily, one of argon, helium, or nitrogen) is introduced into the reaction vessel to remove excess gas for 30-60 minutes. After adding the initiator, the reaction is allowed to proceed for 4-36 hours. During the grafting reaction, an inert gas is continuously introduced to maintain an inert atmosphere and prevent reaction termination due to free radical oxidation. It should be noted that the required reaction time varies depending on the type of monomer. The reaction is terminated when the grafting rate tends to stabilize.

[0065] It should be noted that when the solute in the modifier aqueous solution in step S2 is a single monomeric substance, the resulting modified resin is a monomeric functionalized modified resin; when the solute in the modifier aqueous solution is two monomeric substances, the resulting modified resin is a multi-ligand chelating resin.

[0066] In one possible design, the matrix resin is D301, the modifier aqueous solution solute is acrylic acid, and the initiator is ammonium persulfate (APS) to obtain a carboxyl-modified resin.

[0067] In one possible design, the matrix resin is D301, the modifier aqueous solution solute is 2-acrylamido-2-methylpropanesulfonic acid (AMPS), and the initiator is ammonium persulfate (APS), to obtain a sulfonic acid-modified resin.

[0068] In one possible design, the matrix resin is D301, the modifier aqueous solution solute is acrylic acid and 2-acrylamido-2-methylpropanesulfonic acid (AMPS), and the initiator is ammonium persulfate (APS), to obtain a carboxyl and sulfonic acid dual-ligand chelating resin.

[0069] Specifically, in step S3, the wet modified resin obtained in step S2 is added to deionized water, stirred and washed, and then filtered. The washing-filtration process is repeated 3 times to remove unreacted monomers, homopolymers and residual initiators. Then, vacuum drying is performed. The vacuum drying process includes: vacuum drying the washed modified resin, controlling the vacuum drying temperature at 50-60℃, to obtain the finished modified resin.

[0070] It should be noted that, as Figure 1 , Figure 2 , Figure 3 As shown, the modified resin adsorbs Ga in an acidic solution. 3+ The mechanisms mainly include the following synergistic effects:

[0071] Coordination bond function: O and N atoms in highly electronegative heteroatomic polar functional groups interact with Ga 3+ Multidentate coordination bonds are formed, generating stable ring structures with four or six coordinations (five-membered / six-membered rings);

[0072] Strong electrostatic attraction: The O atoms in the functional group are surrounded by a large number of negative charges, which has a strong effect on Ga. 3+ It has strong electrostatic attraction, thus causing adsorption;

[0073] Chelation effect: Multiple ligands simultaneously react with Ga 3+ Coordinate bonds are formed, and the entropy loss of the system is reduced through multidentate coordination. At the same time, the synergistic effect of multi-coordinate bonds significantly improves the binding strength.

[0074] Physical mass transfer aid: The macroporous structure of the matrix resin can accelerate Ga 3+ It diffuses to the active site, improving the utilization rate of the active site.

[0075] This invention uses a macroporous, weakly basic resin as a substrate, whose high specific surface area and stable structure are well-suited for the acid leaching process of coal-based gallium resources. By densely grafting highly electronegative functional groups such as carboxyl and sulfonic acid groups onto the resin framework and synergistically introducing multiple ligand groups, a multidentate synergistic effect is formed, significantly improving the extraction of gallium from Ga. 3+ It has selective adsorption capacity; at the same time, the optimized modification process enables the resin to have both high grafting rate, strong stability and long service life.

[0076] This invention combines optimized application processes with modified resins of specific structures to target Ga in complex acidic systems. 3+ The adsorption and desorption processes were dually optimized. The parameters such as pH range, temperature, time, and liquid-solid ratio worked synergistically to effectively inhibit Al3+ and Fe3+. 3+ Co-adsorption of major competing ions is achieved, while ensuring high adsorption capacity and excellent recyclability of the resin (adsorption capacity retention ≥86% after 5 cycles).

[0077] The application of modified resin in adsorbing gallium in acidic systems will be described below with reference to specific examples.

[0078] Example 1

[0079] This embodiment provides a method for adsorbing gallium using a monomeric carboxyl-modified resin in an acidic system.

[0080] The extraction of gallium from an acidic gallium-containing solution with a concentration of 50 mg / L and a pH of 3 is performed using the following process:

[0081] S1: Adsorption, the modified resin is mixed with an acidic gallium-containing solution for adsorption treatment, followed by solid-liquid separation to obtain a gallium-loaded saturated modified resin.

[0082] The adsorption temperature was 40℃, the mass-to-volume ratio of carboxyl-modified resin to acidic gallium-containing solution was 0.02g:60mL, and the adsorption time was 28h.

[0083] S2: Desorption. The saturated modified resin is mixed with hydrochloric acid aqueous solution to desorb gallium ions from the modified resin. After desorption is completed, solid-liquid separation is performed to obtain regenerated modified resin and gallium-containing desorption solution.

[0084] The mass-to-volume ratio of saturated modified resin to hydrochloric acid aqueous solution was 0.03 g: 10 mL, the desorption temperature was 40 °C, and the desorption time was 3 h.

[0085] The preparation method of the monomer carboxyl-modified resin includes the following steps:

[0086] S1: Add excess deionized water to 1g D301 (base resin), stir and wash at 500rpm for 8min, then vacuum filter to remove water, and repeat the stirring-washing-vacuum filtration process 3 times. Dry the treated resin under vacuum at 60℃ to constant weight.

[0087] S2: Mix 5g of acrylic acid (modifier), NaOH, and deionized water in a certain proportion to obtain a sodium acrylate solution with a pH of 7.0±0.2 and a monomer mass concentration of 20%.

[0088] Ammonium persulfate (APS, initiator) was mixed with deionized water to prepare an APS aqueous solution with a mass concentration of 1.0% (i.e., the amount of initiator APS was 1.0 wt% of the mass of acrylic acid in the modifier aqueous solution);

[0089] The cleaned D301 and sodium acrylate solution were mixed to obtain a mixture. Nitrogen gas was introduced into the reaction vessel for 40 minutes. Then APS was added to the mixture. The mixture was stirred at 1000 rpm for 4 hours at 45°C under a continuous nitrogen atmosphere. After the reaction was terminated, solid-liquid separation was performed to obtain wet modified resin.

[0090] S3: Add the wet modified resin obtained in step S2 to deionized water, stir and wash, then filter, repeat the washing-filtering process 3 times, and then vacuum dry at 60℃ to obtain the finished modified resin.

[0091] In this embodiment, the mass grafting rate of the functional groups in the monomer carboxyl-modified resin is 25.68%, as detailed in Table 1; the mass grafting rate is obtained using the following formula:

[0092]

[0093] G: Grafting rate of modified resin, %; m0: Mass of base resin before grafting, g; m1: Mass of modified resin after grafting reaction, g.

[0094] The method for calculating the saturated adsorption capacity of the resin is as follows: filter and separate the resin and solution after adsorption, take the solutions before and after adsorption, dilute them, and use ICP to measure the gallium ion concentration in the solutions before and after adsorption, and then calculate the saturated adsorption capacity of the resin.

[0095] The saturated adsorption capacity of the monomer carboxyl-modified resin in this embodiment is 198.34 mg / g. After 5 adsorption-desorption cycles, the adsorption capacity retention rate of the resin for gallium is 87.22%.

[0096] Example 2

[0097] This embodiment provides the application of monomeric carboxyl-modified resin in adsorbing gallium in an acidic system.

[0098] The extraction of gallium from an acidic gallium-containing solution with a concentration of 80 mg / L and a pH of 2.5 is performed using a process similar to that in Example 1, except that:

[0099] In step S1, the adsorption temperature is 50℃, the mass-to-volume ratio of carboxyl-modified resin to acidic gallium-containing solution is 0.04g:60mL, and the adsorption time is 32h.

[0100] In step S2, the mass-to-volume ratio of saturated modified resin to hydrochloric acid aqueous solution is 0.02 g: 10 mL, the desorption temperature is 50 °C, and the desorption time is 2.5 h.

[0101] The preparation method of the monomer carboxyl-modified resin is similar to that of the monomer carboxyl-modified resin in Example 1, except that:

[0102] In step S2, the amount of initiator APS is 1.3 wt% of the mass of acrylic acid in the modified aqueous solution; the reaction is carried out at 50°C and under a continuous nitrogen atmosphere with a stirring speed of 900 rpm for 8 hours.

[0103] In this embodiment, the grafting rate of the functional groups in the monomer carboxyl-modified resin is 27.73%.

[0104] The saturated adsorption capacity of the monomer carboxyl-modified resin used in this embodiment is 196.27 mg / g. After 5 adsorption-desorption cycles, the adsorption capacity retention rate of the resin for gallium is 88.13%.

[0105] Example 3

[0106] This embodiment provides the application of monomeric carboxyl-modified resin in adsorbing gallium in an acidic system.

[0107] The extraction of gallium from an acidic gallium-containing solution with a concentration of 80 mg / L and a pH of 2.5 is performed using a process similar to that in Example 1, except that:

[0108] In step S1, the adsorption temperature is 55℃, the mass-volume ratio of carboxyl-modified resin to acidic gallium-containing solution is 0.05g:60mL, and the adsorption time is 36h.

[0109] In step S2, the mass-to-volume ratio of saturated modified resin to hydrochloric acid aqueous solution is 0.02 g: 10 mL, the desorption temperature is 55 °C, and the desorption time is 3.5 h.

[0110] The preparation method of the monomer carboxyl-modified resin is similar to that of the monomer carboxyl-modified resin in Example 1, except that:

[0111] In step S2, the amount of acrylic acid (modifier) ​​is 7.5g, and the amount of initiator APS is 1.3wt% of the mass of acrylic acid in the modified aqueous solution; the reaction is carried out at 50°C and under a continuous nitrogen atmosphere with a stirring speed of 900rpm for 8h.

[0112] In this embodiment, the grafting rate of the functional groups of the monomer carboxyl modified resin is 37.11%.

[0113] The saturated adsorption capacity of the monomer carboxyl-modified resin used in this embodiment is 278.88 mg / g. After 5 adsorption-desorption cycles, the adsorption capacity retention rate of the resin for gallium is 89.72%.

[0114] Example 4

[0115] This embodiment provides the application of monomeric carboxyl-modified resin in adsorbing gallium in an acidic system.

[0116] The extraction of gallium from an acidic gallium-containing solution with a concentration of 80 mg / L and a pH of 2.5 is performed using a process similar to that in Example 1, except that:

[0117] In step S1, the adsorption temperature is 50℃, the mass-to-volume ratio of carboxyl-modified resin to acidic gallium-containing solution is 0.04g:60mL, and the adsorption time is 34h.

[0118] In step S2, the mass-to-volume ratio of saturated modified resin to hydrochloric acid aqueous solution is 0.02 g: 10 mL, the desorption temperature is 50 °C, and the desorption time is 3.5 h.

[0119] The preparation method of the monomer carboxyl-modified resin is similar to that of the monomer carboxyl-modified resin in Example 1, except that:

[0120] In step S2, the amount of acrylic acid (modifier) ​​is 10g, and the amount of initiator APS is 1.0wt% of the mass of acrylic acid in the modified aqueous solution; the reaction is carried out at 50°C and under a continuous nitrogen atmosphere with a stirring speed of 900rpm for 8h.

[0121] In this embodiment, the functional groups of the monomer carboxyl-modified resin have a grafting rate of 32.69% by mass.

[0122] The saturated adsorption capacity of the monomer carboxyl-modified resin used in this embodiment is 227.14 mg / g. After 5 adsorption-desorption cycles, the adsorption capacity retention rate of the resin for gallium is 88.25%.

[0123] Example 5

[0124] This embodiment provides the application of monomeric carboxyl-modified resin in adsorbing gallium in an acidic system.

[0125] The extraction of gallium from an acidic gallium-containing solution with a concentration of 80 mg / L and a pH of 2.5 is performed using a process similar to that in Example 1, except that:

[0126] In step S1, the adsorption temperature is 45℃, the mass-to-volume ratio of carboxyl-modified resin to acidic gallium-containing solution is 0.04g:60mL, and the adsorption time is 34h.

[0127] In step S2, the mass-to-volume ratio of saturated modified resin to hydrochloric acid aqueous solution is 0.02 g: 10 mL, the desorption temperature is 55 °C, and the desorption time is 3 h.

[0128] The preparation method of the monomer carboxyl-modified resin is similar to that of the monomer carboxyl-modified resin in Example 1, except that:

[0129] The base resin is D307;

[0130] In step S2, the amount of acrylic acid (modifier) ​​used is 7.5g, and the amount of initiator APS is 1.6wt% of the mass of acrylic acid in the modified aqueous solution; the reaction is carried out at 50°C and under a continuous nitrogen atmosphere with a stirring speed of 900rpm for 8h.

[0131] In this embodiment, the grafting rate of the functional groups of the monomer carboxyl modified resin is 29.83%.

[0132] The saturated adsorption capacity of the monomer carboxyl-modified resin used in this embodiment is 202.27 mg / g. After 5 adsorption-desorption cycles, the adsorption capacity retention rate of the resin for gallium is 88.28%.

[0133] Example 6

[0134] This embodiment provides the application of monomeric sulfonic acid-modified resin in adsorbing gallium in an acidic system.

[0135] The extraction of gallium from an acidic gallium-containing solution with a concentration of 200 mg / L and a pH of 2 is performed using a process similar to that in Example 1, except that:

[0136] In step S1, the adsorption temperature is 35℃, the mass-volume ratio of sulfonic acid-modified resin to acidic gallium-containing solution is 0.01g:60mL, and the adsorption time is 28h.

[0137] In step S2, the mass-to-volume ratio of saturated modified resin to hydrochloric acid aqueous solution is 0.04 g: 10 mL, the desorption temperature is 40 °C, and the desorption time is 2 h.

[0138] The preparation method of the monomer sulfonic acid modified resin includes the following steps:

[0139] S1: Add excess deionized water to 1g D301 (base resin), stir and wash at 600rpm for 6min, then vacuum filter to remove water, and repeat the stirring-washing-vacuum filtration process 3 times. Dry the treated resin under vacuum at 60℃ to constant weight.

[0140] S2: Mix 5g of 2-acrylamido-2-methylpropanesulfonic acid (AMPS, modifier) ​​and deionized water in a certain proportion to obtain an AMPS solution with a monomer mass concentration of 20%.

[0141] Ammonium persulfate (APS, initiator) was mixed with deionized water to prepare an APS aqueous solution with a mass concentration of 1.0% (i.e., the amount of initiator APS was 1.0 wt% of the mass of AMPS in the modifier aqueous solution);

[0142] The cleaned D301 and AMPS solutions were mixed to obtain a mixture. Nitrogen gas was introduced into the reaction vessel for 30 minutes. Then, APS was added to the mixture. The mixture was stirred at 900 rpm for 8 hours at 50°C under a continuous nitrogen atmosphere. After the reaction was terminated, solid-liquid separation was performed to obtain wet modified resin.

[0143] S3: Add the wet modified resin obtained in step S2 to deionized water, stir and wash, then filter, repeat the washing-filtering process 3 times, and then vacuum dry at 60℃ to obtain the finished modified resin.

[0144] In this embodiment, the functional groups of the monomer sulfonic acid-modified resin have a grafting rate of 22.34%.

[0145] The saturated adsorption capacity of the monomer sulfonic acid modified resin used in this embodiment is 197.81 mg / g. After 5 adsorption-desorption cycles, the adsorption capacity retention rate of the resin for gallium is 86.84%.

[0146] Example 7

[0147] This embodiment provides the application of monomeric sulfonic acid-modified resin in adsorbing gallium in an acidic system.

[0148] The extraction of gallium from an acidic gallium-containing solution with a concentration of 200 mg / L and a pH of 2 is performed using a process similar to that in Example 1, except that:

[0149] In step S1, the adsorption temperature is 45℃, the mass-volume ratio of sulfonic acid-modified resin to acidic gallium-containing solution is 0.03g:60mL, and the adsorption time is 36h.

[0150] In step S2, the mass-to-volume ratio of saturated modified resin to hydrochloric acid aqueous solution is 0.03 g: 10 mL, the desorption temperature is 50 °C, and the desorption time is 2.5 h.

[0151] The preparation method of the monomer sulfonic acid modified resin is similar to that in Example 6, except that:

[0152] In step S2, the amount of 2-acrylamido-2-methylpropanesulfonic acid (AMPS, modifier) ​​is 10g, and the amount of initiator APS is 0.5wt% of the mass of acrylic acid in the modified aqueous solution; the reaction is carried out at 50°C and under a continuous nitrogen atmosphere with a stirring speed of 900rpm for 8h.

[0153] The grafting rate of the monomer sulfonic acid modified resin used in this embodiment is 30.63%.

[0154] The saturated adsorption capacity of the monomer sulfonic acid modified resin used in this embodiment is 193.27 mg / g. After 5 adsorption-desorption cycles, the adsorption capacity retention rate of the resin for gallium is 87.05%.

[0155] Example 8

[0156] This embodiment provides the application of monomeric sulfonic acid-modified resin in adsorbing gallium in an acidic system.

[0157] The extraction of gallium from an acidic gallium-containing solution with a concentration of 200 mg / L and a pH of 2 is performed using a process similar to that in Example 1, except that:

[0158] In step S1, the adsorption temperature is 55℃, the mass-volume ratio of sulfonic acid-modified resin to acidic gallium-containing solution is 0.05g:60mL, and the adsorption time is 36h.

[0159] In step S2, the mass-to-volume ratio of saturated modified resin to hydrochloric acid aqueous solution is 0.03 g: 10 mL, the desorption temperature is 50 °C, and the desorption time is 4 h.

[0160] The preparation method of the monomer sulfonic acid modified resin is similar to that in Example 6, except that:

[0161] In step S2, the amount of 2-acrylamido-2-methylpropanesulfonic acid (AMPS, modifier) ​​is 10g, and the amount of initiator APS is 0.5wt% of the mass of acrylic acid in the modified aqueous solution; the reaction is carried out at 60°C and under a continuous nitrogen atmosphere with a stirring speed of 600rpm for 20h.

[0162] In this embodiment, the functional groups of the monomer sulfonic acid-modified resin have a grafting rate of 37.23%.

[0163] The saturated adsorption capacity of the monomer sulfonic acid modified resin used in this embodiment is 237.86 mg / g. After 5 adsorption-desorption cycles, the adsorption capacity retention rate of the resin for gallium is 88.41%.

[0164] Example 9

[0165] This embodiment provides the application of monomeric sulfonic acid-modified resin in adsorbing gallium in an acidic system.

[0166] The extraction of gallium from an acidic gallium-containing solution with a concentration of 200 mg / L and a pH of 2 is performed using a process similar to that in Example 1, except that:

[0167] In step S1, the adsorption temperature is 45℃, the mass-volume ratio of sulfonic acid-modified resin to acidic gallium-containing solution is 0.04g:60mL, and the adsorption time is 30h.

[0168] In step S2, the mass-to-volume ratio of saturated modified resin to hydrochloric acid aqueous solution is 0.04 g: 10 mL, the desorption temperature is 45 °C, and the desorption time is 2.5 h.

[0169] The preparation method of the monomer sulfonic acid modified resin is similar to that in Example 6, except that:

[0170] In step S2, the amount of 2-acrylamido-2-methylpropanesulfonic acid (AMPS, modifier) ​​is 15g, and the amount of initiator APS is 1.0wt% of the mass of acrylic acid in the modified aqueous solution; the reaction is carried out at 60°C and under a continuous nitrogen atmosphere with a stirring speed of 600rpm for 20h.

[0171] In this embodiment, the functional groups of the monomer sulfonic acid-modified resin have a grafting rate of 29.25%.

[0172] The saturated adsorption capacity of the monomer sulfonic acid modified resin used in this embodiment is 195.63 mg / g. After 5 adsorption-desorption cycles, the adsorption capacity retention rate of the resin for gallium is 87.43%.

[0173] Example 10

[0174] This embodiment provides the application of monomeric sulfonic acid-modified resin in adsorbing gallium in an acidic system.

[0175] The extraction of gallium from an acidic gallium-containing solution with a concentration of 200 mg / L and a pH of 2 is performed using a process similar to that in Example 1, except that:

[0176] In step S1, the adsorption temperature is 50℃, the mass-volume ratio of sulfonic acid-modified resin to acidic gallium-containing solution is 0.04g:60mL, and the adsorption time is 32h.

[0177] In step S2, the mass-to-volume ratio of saturated modified resin to hydrochloric acid aqueous solution is 0.04 g: 10 mL, the desorption temperature is 45 °C, and the desorption time is 2.5 h.

[0178] The preparation method of the monomer sulfonic acid modified resin is similar to that in Example 6, except that:

[0179] The base resin is D709;

[0180] In step S2, the amount of 2-acrylamido-2-methylpropanesulfonic acid (AMPS, modifier) ​​is 12g, and the amount of initiator APS is 0.8wt% of the mass of acrylic acid in the modified aqueous solution; the reaction is carried out at 60°C and under a continuous nitrogen atmosphere with a stirring speed of 600rpm for 20h.

[0181] In this embodiment, the functional groups of the monomer sulfonic acid-modified resin have a grafting rate of 33.95%.

[0182] The saturated adsorption capacity of the monomer sulfonic acid modified resin used in this embodiment is 194.55 mg / g. After 5 adsorption-desorption cycles, the adsorption capacity retention rate of the resin for gallium is 87.96%.

[0183] Example 11

[0184] This embodiment provides the application of multi-ligand chelate modified resin for gallium adsorption in acidic systems.

[0185] The extraction of gallium from an acidic gallium-containing solution with a concentration of 100 mg / L and a pH of 2 is performed using a process similar to that in Example 1, except that:

[0186] In step S1, the adsorption temperature is 55℃, the mass-to-volume ratio of the multi-ligand chelating modified resin to the acidic gallium-containing solution is 0.03g:60mL, and the adsorption time is 32h.

[0187] In step S2, the mass-to-volume ratio of saturated modified resin to hydrochloric acid aqueous solution is 0.02 g: 10 mL, the desorption temperature is 50 °C, and the desorption time is 2.5 h.

[0188] The preparation method of the multi-ligand chelate modified resin includes the following steps:

[0189] S1: Add excess deionized water to 1g D301 (base resin), stir and wash at 600rpm for 6min, then vacuum filter to remove water, and repeat the stirring-washing-vacuum filtration process 3 times. Dry the treated resin under vacuum at 60℃ to constant weight.

[0190] S2: Acrylic acid and 2-acrylamido-2-methylpropanesulfonic acid (AMPS) are selected as modifiers, wherein the mass ratio of acrylic acid to AMPS is 1:1;

[0191] Sodium acrylate solution (obtained by mixing acrylic acid, NaOH, and deionized water in a certain proportion, with a pH of 7.0±0.2) and AMPS aqueous solution (obtained by mixing AMPS and deionized water in a certain proportion) were prepared separately. The sodium acrylate solution and AMPS aqueous solution were mixed to obtain a modifier aqueous solution, wherein the total mass concentration of the modifier monomer was 10%.

[0192] Ammonium persulfate (APS, initiator) was mixed with deionized water to prepare an APS aqueous solution with a mass concentration of 1.0% (i.e., the amount of initiator APS was 1.0 wt% of the total mass of the mixed monomers in the modifier aqueous solution);

[0193] The cleaned D301 and the mixed modifier aqueous solution were mixed to obtain a mixture. Nitrogen gas was introduced into the reaction vessel for 30 minutes, and then APS was added to the mixture. The mixture was reacted at 50°C with a continuous nitrogen atmosphere and a stirring speed of 900 rpm for 8 hours. After the reaction was terminated, solid-liquid separation was performed to obtain wet modified resin.

[0194] S3: Add the wet modified resin obtained in step S2 to deionized water, stir and wash, then filter, repeat the washing-filtering process 3 times, and then vacuum dry at 60℃ to obtain the finished modified resin.

[0195] In this embodiment, the functional groups of the multi-ligand chelate modified resin have a grafting rate of 22.92%.

[0196] The saturated adsorption capacity of the multi-ligand chelating modified resin used in this embodiment is 198.36 mg / g. After 5 adsorption-desorption cycles, the adsorption capacity retention rate of the resin for gallium is 89.52%.

[0197] Example 12

[0198] This embodiment provides the application of multi-ligand chelate modified resin for gallium adsorption in acidic systems.

[0199] The extraction of gallium from an acidic gallium-containing solution with a concentration of 100 mg / L and a pH of 2 is performed using a process similar to that in Example 1, except that:

[0200] In step S1, the adsorption temperature is 50℃, the mass-to-volume ratio of the multi-ligand chelating modified resin to the acidic gallium-containing solution is 0.04g:60mL, and the adsorption time is 34h.

[0201] In step S2, the mass-to-volume ratio of saturated modified resin to hydrochloric acid aqueous solution is 0.03 g: 10 mL, the desorption temperature is 50 °C, and the desorption time is 2 h.

[0202] The preparation method of the multi-ligand chelate modified resin is similar to that in Example 11, except that:

[0203] In step S2, the total mass concentration of the modified monomer in the modifier aqueous solution composed of sodium acrylate solution and AMPS aqueous solution is 25%.

[0204] In this embodiment, the functional groups of the multi-ligand chelate modified resin have a grafting rate of 41.56%.

[0205] The saturated adsorption capacity of the multi-ligand chelating modified resin used in this embodiment is 313.71 mg / g. After 5 adsorption-desorption cycles, the adsorption capacity retention rate of the resin for gallium is 90.63%.

[0206] Example 13

[0207] This embodiment provides the application of multi-ligand chelate modified resin for gallium adsorption in acidic systems.

[0208] The extraction of gallium from an acidic gallium-containing solution with a concentration of 100 mg / L and a pH of 2 is performed using a process similar to that in Example 1, except that:

[0209] In step S1, the adsorption temperature is 50℃, the mass-to-volume ratio of the multi-ligand chelating modified resin to the acidic gallium-containing solution is 0.05g:60mL, and the adsorption time is 36h.

[0210] In step S2, the mass-to-volume ratio of saturated modified resin to hydrochloric acid aqueous solution is 0.02 g: 10 mL, the desorption temperature is 50 °C, and the desorption time is 3 h.

[0211] The preparation method of the multi-ligand chelate modified resin is similar to that in Example 11, except that:

[0212] In step S2, the total mass concentration of the modified monomer in the modifier aqueous solution composed of sodium acrylate solution and AMPS aqueous solution is 20%.

[0213] The amount of initiator APS is 0.6 wt% of the total mass of the mixed monomers in the modified aqueous solution;

[0214] In this embodiment, the functional groups of the multi-ligand chelate modified resin have a grafting rate of 43.55%.

[0215] The saturated adsorption capacity of the multi-ligand chelating modified resin used in this embodiment is 348.30 mg / g. After 5 adsorption-desorption cycles, the adsorption capacity retention rate of the resin for gallium is 91.24%.

[0216] In this embodiment, the modified resin was subjected to an adsorption-desorption recycling test. Using the resin desorbed in step S2 of the application method as the final amount of resin, the adsorption-desorption process from S1 to S2 was repeated, and the adsorption capacity of the resin after each recycling was recorded. The results are as follows: Figure 4 As shown, after five repeated uses, the adsorption capacity of the modified resin decreased to 309.88 mg / g, a relatively small decrease, indicating that the multi-ligand chelating resin has a certain degree of stability and good reusability.

[0217] Example 14

[0218] This embodiment provides the application of multi-ligand chelate modified resin for gallium adsorption in acidic systems.

[0219] The extraction of gallium from an acidic gallium-containing solution with a concentration of 100 mg / L and a pH of 2 is performed using a process similar to that in Example 1, except that:

[0220] In step S1, the adsorption temperature is 40℃, the mass-to-volume ratio of the multi-ligand chelating modified resin to the acidic gallium-containing solution is 0.03g:60mL, and the adsorption time is 34h.

[0221] In step S2, the mass-to-volume ratio of saturated modified resin to hydrochloric acid aqueous solution is 0.03 g: 10 mL, the desorption temperature is 50 °C, and the desorption time is 2.5 h.

[0222] The preparation method of the multi-ligand chelate modified resin is similar to that in Example 11, except that:

[0223] In step S2, the total mass concentration of the modified monomer in the modifier aqueous solution composed of sodium acrylate solution and AMPS aqueous solution is 20%.

[0224] The amount of initiator APS is 0.6 wt% of the total mass of the mixed monomers in the modified aqueous solution;

[0225] The reaction was carried out at 40°C under a continuous nitrogen atmosphere and stirred at 900 rpm for 8 hours.

[0226] In this embodiment, the functional groups of the multi-ligand chelate modified resin have a grafting rate of 36.04%.

[0227] The saturated adsorption capacity of the multi-ligand chelating modified resin used in this embodiment is 263.55 mg / g. After 5 adsorption-desorption cycles, the adsorption capacity retention rate of the resin for gallium is 90.15%.

[0228] Example 15

[0229] This embodiment provides the application of multi-ligand chelate modified resin for gallium adsorption in acidic systems.

[0230] The extraction of gallium from an acidic gallium-containing solution with a concentration of 100 mg / L and a pH of 2 is performed using a process similar to that in Example 1, except that:

[0231] In step S1, the adsorption temperature is 50℃, the mass-to-volume ratio of the multi-ligand chelating modified resin to the acidic gallium-containing solution is 0.05g:60mL, and the adsorption time is 36h.

[0232] In step S2, the mass-to-volume ratio of saturated modified resin to hydrochloric acid aqueous solution is 0.02 g: 10 mL, the desorption temperature is 50 °C, and the desorption time is 2.5 h.

[0233] The preparation method of the multi-ligand chelate modified resin is similar to that in Example 11, except that:

[0234] In step S2, fumaric acid and acryloyloxyethyl phosphate are selected as modifiers, wherein the mass ratio of fumaric acid to acryloyloxyethyl phosphate is 1:2.

[0235] The total mass concentration of the modifier aqueous solution, which is composed of fumaric acid aqueous solution and acryloyloxyethyl phosphate aqueous solution, is 20%.

[0236] The amount of initiator APS is 0.8 wt% of the total mass of the mixed monomers in the aqueous solution of the modifier;

[0237] The grafting rate of the multi-ligand chelate modified resin used in this embodiment is 42.37%.

[0238] The saturated adsorption capacity of the multi-ligand chelating modified resin used in this embodiment is 368.92 mg / g. After 5 adsorption-desorption cycles, the adsorption capacity retention rate of the resin for gallium is 91.97%.

[0239] Example 16

[0240] This embodiment provides the application of multi-ligand chelate modified resin for gallium adsorption in acidic systems.

[0241] The extraction of gallium from an acidic gallium-containing solution with a concentration of 100 mg / L and a pH of 2 is performed using a process similar to that in Example 1, except that:

[0242] In step S1, the adsorption temperature is 45℃, the mass-to-volume ratio of the multi-ligand chelating modified resin to the acidic gallium-containing solution is 0.04g:60mL, and the adsorption time is 32h.

[0243] In step S2, the mass-to-volume ratio of saturated modified resin to hydrochloric acid aqueous solution is 0.04 g: 10 mL, the desorption temperature is 50 °C, and the desorption time is 2.5 h.

[0244] The preparation method of the multi-ligand chelate modified resin is similar to that in Example 11, except that:

[0245] In step S2, acrylamide and acryloyloxyethyl phosphate are selected as modifiers, wherein the mass ratio of acrylamide to acryloyloxyethyl phosphate is 1:2.

[0246] In the modifier aqueous solution composed of acrylamide aqueous solution and acryloyloxyethyl phosphate aqueous solution, the total mass concentration of the modifier monomer is 20%.

[0247] In this embodiment, the functional groups of the multi-ligand chelate modified resin have a grafting rate of 39.42%.

[0248] The saturated adsorption capacity of the multi-ligand chelating modified resin used in this embodiment is 297.48 mg / g. After 5 adsorption-desorption cycles, the adsorption capacity retention rate of the resin for gallium is 89.93%.

[0249] Comparative Example 1

[0250] This comparative example provides an application of D301 resin in adsorbing gallium in an acidic system, specifically for the extraction of gallium from an acidic gallium-containing solution with a concentration of 50 mg / L and a pH of 3. The specific process is the same as in Example 1.

[0251] The saturated adsorption capacity of the modified resin in this comparative example was 115.76 mg / g. After 5 adsorption-desorption cycles, the adsorption capacity of the resin for gallium was retained at 86.44%.

[0252] Comparative Example 2

[0253] This comparative example provides a method for adsorbing gallium using a monomeric carboxyl-modified resin in an acidic system.

[0254] The monomer carboxyl-modified resin used is the same as that in Example 1.

[0255] The application method is similar to that in Example 1, except that the adsorption time in step S1 is 8 hours.

[0256] The saturated adsorption capacity of the modified resin in this comparative example was 82.41 mg / g. After 5 adsorption-desorption cycles, the adsorption capacity of the resin for gallium was retained at 81.20%.

[0257] Comparative Example 3

[0258] This comparative example provides a method for adsorbing gallium using a monomeric carboxyl-modified resin in an acidic system.

[0259] The monomer carboxyl-modified resin used is the same as that in Example 1.

[0260] The application method is similar to that in Example 1, except that the adsorption temperature in step S1 is 20°C.

[0261] The saturated adsorption capacity of the modified resin in this comparative example was 92.43 mg / g. After 5 adsorption-desorption cycles, the adsorption capacity of the resin for gallium was retained at 80.37%.

[0262] Comparative Example 4

[0263] This comparative example provides a method for adsorbing gallium using a monomeric carboxyl-modified resin in an acidic system.

[0264] The monomer carboxyl-modified resin used is the same as that in Example 1.

[0265] The application method is similar to that in Example 1, except that in step S2, the mass-to-volume ratio of saturated modified resin to hydrochloric acid aqueous solution is 0.08 g: 10 mL.

[0266] The modified resin in this comparative application example has a saturated adsorption capacity of 90.36 mg / g, and after 5 adsorption-desorption cycles, the resin retains 77.46% of its gallium adsorption capacity.

[0267] Comparative Example 5

[0268] This comparative example provides a method for applying multi-ligand chelate modified resins to adsorb gallium in acidic systems.

[0269] The monomer carboxyl-modified resin used is the same as in Example 13.

[0270] The application method is similar to that of Example 13, except that:

[0271] In step S1, the adsorption time is 8 hours;

[0272] The modified resin in this comparative example had a saturated adsorption capacity of 115.08 mg / g, and after 5 adsorption-desorption cycles, the resin retained 82.78% of its gallium adsorption capacity.

[0273] Comparative Example 6

[0274] This comparative example provides a method for applying multi-ligand chelate modified resins to adsorb gallium in acidic systems.

[0275] The monomer carboxyl-modified resin used is the same as in Example 13.

[0276] The application method is similar to that in Example 13, except that the adsorption temperature in step S1 is 20°C.

[0277] The saturated adsorption capacity of the modified resin in this comparative example was 186.53 mg / g. After 5 adsorption-desorption cycles, the adsorption capacity of the resin for gallium was retained at 83.02%.

[0278] Comparative Example 7

[0279] This comparative example provides a method for applying multi-ligand chelate modified resins to adsorb gallium in acidic systems.

[0280] The monomer carboxyl-modified resin used is the same as in Example 13.

[0281] The application method is similar to that of Example 13, except that:

[0282] In step S2, the mass-to-volume ratio of saturated modified resin to hydrochloric acid aqueous solution is 0.08 g: 10 mL.

[0283] The saturated adsorption capacity of the modified resin in this comparative example was 106.86 mg / g. After 5 adsorption-desorption cycles, the adsorption capacity retention rate of the resin for gallium was 80.33%.

[0284] Comparative Example 8

[0285] This comparative example provides a method for applying modified resin to adsorb gallium in an acidic system.

[0286] The extraction of gallium from an acidic gallium-containing solution with a concentration of 100 mg / L and a pH of 2 was performed using the same process as in Example 1.

[0287] The base resin in the single-modified resin used was a non-macroporous 312 resin, and other conditions were the same as in Example 3.

[0288] The grafting rate of the functional groups of the modified resin used in this comparative example was 21.36%.

[0289] The modified resin used in this comparative application had a saturated adsorption capacity of 93.31 mg / g, and after 5 adsorption-desorption cycles, the resin retained 82.05% of its gallium adsorption capacity.

[0290] Comparative Example 9

[0291] This comparative example provides a method for adsorbing gallium using a monomeric carboxyl-modified resin in an acidic system.

[0292] The application method is similar to that in Example 3, except that in the preparation method of the monomer carboxyl modified resin, the amount of initiator APS is 3.0 wt% of the mass of acrylic acid in the modified aqueous solution;

[0293] The grafting rate of the functional groups of the monomer carboxyl-modified resin used in this comparative example was 19.45%.

[0294] The modified resin used in this comparative application had a saturated adsorption capacity of 78.45 mg / g, and after 5 adsorption-desorption cycles, the resin retained 77.43% of its gallium adsorption capacity.

[0295] Comparative Example 10

[0296] This comparative example provides a method for adsorbing gallium using a monomeric carboxyl-modified resin in an acidic system.

[0297] The application method is similar to that in Example 3, except that in the preparation method of the monomer carboxyl modified resin, in step S2, the reaction is carried out at 25°C and under a continuous nitrogen atmosphere with a stirring speed of 900 rpm for 8 hours.

[0298] The grafting rate of the functional groups of the monomer carboxyl-modified resin used in this comparative example was 18.78%.

[0299] The modified resin used in this comparative application had a saturated adsorption capacity of 69.76 mg / g, and after 5 adsorption-desorption cycles, the resin retained 70.32% of its gallium adsorption capacity.

[0300] Comparative Example 11

[0301] This comparative example provides a method for adsorbing gallium using a monomeric carboxyl-modified resin in an acidic system.

[0302] The application method is similar to that in Example 3, except that the amount of acrylic acid (modifier) ​​used in the preparation method of the monomer carboxyl modified resin is 20g.

[0303] The grafting rate of the functional groups of the monomer carboxyl-modified resin used in this comparative example was 21.65%.

[0304] The modified resin used in this comparative application had a saturated adsorption capacity of 95.78 mg / g, and after 5 adsorption-desorption cycles, the resin retained 82.43% of its gallium adsorption capacity.

[0305] Comparative Example 12

[0306] This comparative example provides a method for applying multi-ligand chelate modified resin to adsorb gallium in an acidic system.

[0307] The application method is similar to that in Example 13, except that in the preparation method of the multi-ligand chelate modified resin, in step S2, the total mass concentration of the modified monomer in the modified aqueous solution composed of sodium acrylate solution and AMPS aqueous solution is 40%.

[0308] The grafting rate of the functional groups in the multi-chelate modified resin used in this comparative example was 29.43%.

[0309] The modified resin used in this comparative application had a saturated adsorption capacity of 143.43 mg / g, and after 5 adsorption-desorption cycles, the resin retained 80.45% of its gallium adsorption capacity.

[0310] Comparative Example 13

[0311] This comparative example provides a method for applying multi-ligand chelate modified resin to adsorb gallium in an acidic system.

[0312] The application method is similar to that in Example 13, except that in the preparation method of the multi-ligand chelate modified resin, in step S2, the total mass concentration of the modified monomer in the modified aqueous solution composed of sodium acrylate solution and AMPS aqueous solution is 5%.

[0313] The grafting rate of the functional groups of the modified resin used in this comparative example was 26.77%.

[0314] The modified resin used in this comparative application had a saturated adsorption capacity of 176.45 mg / g, and after 5 adsorption-desorption cycles, the adsorption capacity of the resin for gallium was retained at 81.42%.

[0315] Table 1 shows the adsorption and desorption conditions, adsorption capacity, and resin capacity retention rate of Examples 1-16 and Comparative Examples 1-13. Table 2 shows the preparation conditions and grafting rates of monomer-modified resins of Examples 1-10 and Comparative Examples 8-11; Table 2 also shows the preparation conditions and grafting rates of multi-ligand chelate-modified resins of Examples 11-16 and Comparative Examples 12-13.

[0316] Figure 1 This is a schematic diagram of the synthetic route and adsorption process for preparing carboxyl-modified resins using acrylic acid as a modifying monomer in Examples 1-5; Figure 2 This is a schematic diagram of the synthetic route and adsorption process for preparing sulfonic acid-modified resins using AMPS as the modified monomer in Examples 6-10. Figure 3 The above are schematic diagrams of the synthetic routes and adsorption processes for preparing multi-ligand chelate modified resins using acrylic acid and AMPS as modified monomers in Examples 11-16. Figure 4 The graph shows the change in gallium adsorption capacity of the modified resin used in Example 13 during 5 adsorption-desorption cycles.

[0317] Table 1. Adsorption and desorption conditions, adsorption capacity, and resin capacity retention of Examples 1-16 and Comparative Examples 1-13.

[0318]

[0319]

[0320] Table 2. Preparation conditions and grafting rates of monomer-modified resins in Examples 1-10 and Comparative Examples 8-11

[0321]

[0322] Table 3. Preparation conditions and grafting rates of multiligand chelation modified resins in Examples 11-16 and Comparative Examples 12-13.

[0323]

[0324]

[0325] As can be seen from Tables 1, 2, and 3, the application methods and process parameters of the modified resins provided in Examples 1-16 for gallium extraction in acidic gallium-containing solutions meet the requirements of this invention. Furthermore, the base resin, modifier, and initiator used in the preparation of the modified resins also meet the requirements of this invention.

[0326] Therefore, the modified resin used has a good grafting rate and good adsorption performance for gallium. Under the conditions set by the method of this invention, the modified resin provided by this invention can effectively adsorb gallium and realize the separation and extraction of gallium. While achieving efficient desorption, it minimizes the chemical and thermal damage to the structure of the modified resin and ensures the excellent recycling performance of the resin (adsorption capacity retention rate ≥86% after 5 cycles).

[0327] Comparative Example 1 uses unmodified base resin D301, which is used to extract gallium from the same acidic gallium-containing solution as in Example 1. The saturated adsorption capacity of the modified resin and the retention rate of the adsorption capacity of the resin for gallium after 5 adsorption-desorption cycles both decreased.

[0328] Compared with Example 1, Comparative Example 2 had a lower adsorption capacity due to the shorter adsorption time; Comparative Example 3 had a lower adsorption capacity due to the lower adsorption temperature; Comparative Example 4 had a lower adsorption capacity due to the larger mass-volume ratio of saturated resin to hydrochloric acid solution, resulting in incomplete desorption and a reduced resin adsorption capacity retention rate after 5 adsorption-desorption cycles.

[0329] Compared with Example 13, Comparative Example 5 had a lower adsorption capacity due to the shorter adsorption time; Comparative Example 6 had a lower adsorption capacity due to the lower adsorption temperature; Comparative Example 7 had a lower adsorption capacity after 5 adsorption-desorption cycles because the mass-volume ratio of saturated resin to hydrochloric acid solution was too large.

[0330] The base resin used in Comparative Example 8 was a non-macroporous 312 resin. The other preparation conditions of the resin were the same as in Example 3. Compared with Example 3, the grafting rate of the resin prepared by Comparative Example 8 was significantly reduced. When used to extract gallium from the same acidic gallium-containing solution as in Example 1, the saturated adsorption capacity of the modified resin and the retention rate of the adsorption capacity of the resin for gallium after 5 adsorption-desorption cycles both decreased.

[0331] Compared with Example 3, in Comparative Example 9, the grafting rate decreased due to excessive initiator dosage during resin preparation. Compared with Example 3, in Comparative Example 10, the grafting rate was lower than that of Example 3 due to lower grafting reaction temperature during resin preparation. Compared with Example 3, in Comparative Example 11, the grafting rate decreased due to excessive modified monomer dosage (compared to the mass of the base resin) during resin preparation. The prepared resin was used to extract gallium from the same acidic gallium-containing solution as in Example 1. The saturated adsorption capacity of the modified resin and the retention rate of the adsorption capacity of the resin for gallium after 5 adsorption-desorption cycles both decreased.

[0332] Compared with Example 13, Comparative Examples 12 and 13 showed that the grafting rate was lower than that of Example 13 due to the excessively high or low concentration of the modifier monomer during the resin preparation process. The prepared resin was used to extract gallium from the same acidic gallium-containing solution as in Example 1. The saturated adsorption capacity of the modified resin and the retention rate of the adsorption capacity of the resin for gallium after 5 adsorption-desorption cycles both decreased.

[0333] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for applying modified resin to adsorb gallium in an acidic system, characterized in that, Includes the following steps: S1: Adsorption, the modified resin is mixed with an acidic gallium-containing solution for adsorption treatment, followed by solid-liquid separation to obtain gallium-loaded saturated modified resin. S2: Desorption. The saturated modified resin is mixed with hydrochloric acid aqueous solution to desorb gallium ions from the modified resin. After desorption is completed, solid-liquid separation is performed to obtain regenerated modified resin and gallium-containing desorption solution. The modified resin is a resin in which at least one functional group, consisting of a carboxyl group, a sulfonic acid group, an amide group, or a phosphate group, is introduced onto a macroporous resin skeleton with weakly basic active sites through a grafting reaction.

2. The application method according to claim 1, characterized in that, The pH value of the acidic gallium-containing solution is 1-5.

3. The application method according to claim 1, characterized in that, In step S1, the mass-to-volume ratio of the modified resin to the acidic gallium-containing solution is (0.01-0.05) g: 60 mL.

4. The application method according to claim 1, characterized in that, In step S1, the adsorption temperature is 30-60℃.

5. The application method according to claim 1, characterized in that, In step S1, the adsorption treatment time is 8-36 hours.

6. The application method according to claim 1, characterized in that, In step S2, the concentration of the hydrochloric acid aqueous solution is 0.1-2 mol / L.

7. The application method according to claim 6, characterized in that, In step S2, the mass-to-volume ratio of the saturated modified resin to the hydrochloric acid aqueous solution is (0.01-0.05) g: 10 mL.

8. The application method according to claim 1, characterized in that, In step S2, the desorption temperature is 30-60℃.

9. The application method according to claim 1, characterized in that, In step S2, the desorption process takes 0.5-8 hours.

10. A method for preparing a modified resin for adsorbing gallium in an acidic system, characterized in that, The application method applicable to any one of claims 1 to 9.

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