Deep well salt mine in-situ impurity ion replacement and symbiotic resource collaborative recovery method

Abstract

The invention provides a deep well salt mine in-situ impurity ion replacement and symbiotic resource collaborative recovery method, and relates to the technical field of salt mine resource development and comprehensive utilization. A pH response type catalyst and a H2O2-ethanol supramolecular structure are designed, a novel composite solvating-out agent is constructed, complexing-in-situ oxidation-crystallization integrated impurity removal can be achieved in the deep well salt mine, deep removal and high-purity recovery of SO4 < 2-> are achieved, meanwhile, by optimizing a reaction path, energy consumption and agent cost are reduced, and economic benefits are improved.

Description

Technical Field

[0001] This invention relates to the field of salt mine resource development and comprehensive utilization technology, specifically a method for in-situ impurity ion replacement and synergistic recovery of symbiotic resources in deep well salt mines. Background Technology

[0002] During the mining and processing of deep salt mines, the brine often contains a large number of impurity ions, such as SO42-. 2- , Ca 2+ Mg 2+ These impurities not only affect the purity of salt products but also lead to problems such as equipment scaling and pipeline corrosion, increasing production costs. Traditional impurity removal methods mainly include chemical precipitation, ion exchange, and membrane separation, but these methods have the following problems in practical applications: Chemical precipitation methods (such as the lime-soda ash process): Large amounts of precipitants (such as Ca(OH)2, Na2CO3) need to be added, resulting in a large amount of sludge and high treatment costs. SO4 2- The removal rate is low (typically only 60%–80%), and it easily introduces new impurities (such as excess Ca). 2+ The recycling process is complex.

[0003] Ion exchange method: The resin is easily affected by high concentrations of Cl. - Pollution, frequent regeneration, and high operating costs; It is only suitable for removing low concentrations of impurities, and is not suitable for deep well brine (SO4). 2- >1.5g / L) poor treatment effect.

[0004] Membrane separation method: Membrane modules are prone to scaling and clogging, requiring frequent cleaning and having a short lifespan. High energy consumption (energy consumption per ton of salt > 3 kWh), poor economic efficiency.

[0005] In recent years, the solution-crystallization method has attracted attention due to its high efficiency and low energy consumption, but existing technologies still have the following shortcomings: Direct oxidation of H2O2: H2O2 decomposes rapidly under high temperature and high salinity conditions, resulting in low utilization (<40%), and it is prone to over-oxidation of Cl. - ; Organic solvent dissolution method (such as methanol, acetone): highly toxic, difficult to recover, and poses safety and environmental risks; Lack of in-situ processing capability: Existing processes are mostly carried out on the ground, which cannot adapt to the high pressure and high temperature environment of deep wells, resulting in increased transportation and processing costs.

[0006] Therefore, there is an urgent need to develop a highly efficient, low-consumption, and environmentally friendly method for in-situ impurity ion replacement and synergistic resource recovery in deep-well salt mines, capable of: Selective removal of SO4 2- , Ca 2+ Impurities, such as Cl, should be avoided. - Loss, while increasing SO4 2- Recovery purity; It adapts to in-situ conditions in deep wells (high pressure, high temperature, high salinity), reducing the burden on surface treatment.

[0007] This technology constructs a novel composite solvent by designing a pH-responsive catalyst and an H2O2-ethanol supramolecular structure, which can achieve integrated depurification of deep salt mines through complexation-in-situ oxidation-crystallization, significantly improving the efficiency of impurity removal and resource recovery. Summary of the Invention

[0008] Technical problems to be solved To address the shortcomings of existing technologies, this invention provides a method for in-situ impurity ion replacement and synergistic recovery of symbiotic resources in deep-well salt mines, thereby solving the problems mentioned in the background section.

[0009] Technical solution To achieve the above objectives, the present invention provides the following technical solution: A method for in-situ impurity ion replacement and synergistic recovery of associated resources in deep-well salt mines includes the following steps: ① Weigh out 30% H2O2, 65.2% ethanol, 0.8% supramolecular template agent, 3% pH-responsive catalyst, 0.5% co-catalyst, 0.3% sodium citrate and 0.2% disodium ethylenediaminetetraacetate according to the mass percentage to prepare a composite solvent; ② The high-concentration sulfur-containing brine is initially filtered to obtain filtrate. A pH adjuster (dilute HCl) is injected to lower the pH of the brine to 3.5-4.0, and the wellbore is preheated to 50±2℃. ③ The composite solvent is dispensed using a high-pressure pump (1.5-2.0 MPa) at a rate of 8-12 m³ / min. 3 Injecting SO4 into the deep well cavity at a flow rate of / h, setting the pressure in the reaction section of the cavity to 1.2-1.8 MPa, and the reaction time to 2-3 hours, using a composite solvent to treat SO4. 2- Complexation and in-situ oxidation are performed to transform SO4 2- Converted to HSO4 - ④ After the reaction is complete, a gradient temperature parameter is set in the wellbore separation section. HSO4 is then crystallized through gradient cooling. - It is converted into Na2SO4·10H2O crystals to achieve SO42- 2- Removal and recycling; The gradient cooling process includes a primary cooling zone, where the temperature is lowered from 60℃ to 45℃ at a rate of 0.5±0.05℃ / min, with a residence time of 30 min; a secondary crystallization zone, where the temperature is lowered from 45℃ to 30℃ at a rate of 0.3±0.03℃ / min, with a residence time of 45 min; and a tertiary ripening zone, where the temperature is lowered from 30℃ to 15℃ at a rate of 0.2±0.02℃ / min, with a residence time of 60 min.

[0010] As a further preferred option, the composite solvent comprises a solvent system, a catalytic system, and a stabilizing system. By mass percentage, the solvent system comprises: 30% H2O2, 65.2% ethanol, and 0.8% supramolecular template agent. The catalytic system consists of: 3% pH-responsive catalyst and 0.5% co-catalyst; The stabilizing system consists of: 0.3% sodium citrate and 0.2% disodium ethylenediaminetetraacetate. The supramolecular template agent is sodium dodecylbenzenesulfonate, and the co-catalyst is Na2WO4.

[0011] As a further preferred option, the pH-responsive catalyst is H3PW 12 O 40 H3PW is loaded onto an amino-modified SiO2 support with a pore size of 4-6 nm and an aminosilane modification amount of 7-9 wt%. 12 O 40 The loading is 12-13 wt%, and the structure is a Keggin structure.

[0012] As a further preferred embodiment, the preparation of the composite solvent includes the following steps: ① Weigh out sodium dodecyl sulfonate in the above mass ratio and slowly add it to the corresponding mass of ethanol at 25-30℃, and age for 2-3 hours; ② Mix H2O2 with the product of step ① under nitrogen protection and gradually increase the temperature to 40-45℃ to construct a supramolecular structure. ③ Add pH-responsive catalyst H3PW 12 O 40 @Aminated SiO2 and corresponding mass of Na2WO4 are mixed, and then corresponding mass of sodium citrate and disodium ethylenediaminetetraacetate are added. After mixing for 2 hours, the mixture is dynamically aged for 24 hours to obtain a composite solvent.

[0013] As a further preferred embodiment, the supramolecular structure is specifically a 1:2 supramolecular structure formed by H2O2 and ethanol, with the following specific structural formula: .

[0014] As a further preferred option, the pH-responsive catalyst H3PW 12 O 40The preparation of aminated SiO2 includes the following steps: ① The SiO2 support was modified with amino groups using 3-aminopropyltriethoxysilane to obtain aminated SiO2; ② H3PW was loaded into the pores of aminated SiO2 by impregnation method. 12 O 40 ; ③ After vacuum encapsulation, H3PW is obtained through microwave-UV synergistic activation. 12 O 40 @Aminated SiO2.

[0015] As a further preferred option, the SiO2 support was expanded by hydrothermal treatment at 110°C for 24 hours with a molar ratio of SiO2:hexadecyltrimethylammonium bromide (CTAB):NH4OH of 1:0.3:0.1, followed by drying at 550°C to obtain SiO2 with a pore size of 4-6 nm.

[0016] As a further optimization, the specific process for microwave-UV synergistic activation is as follows: microwave power of 300W, pulse (5s on / 5s off), UV wavelength of 254nm, and 15mW / cm². 2 Microwave and UV activation times were both 5 seconds, and the process was repeated for 30 minutes.

[0017] Beneficial effects This invention provides a method for in-situ impurity ion replacement and synergistic recovery of symbiotic resources in deep-well salt mines, which has the following beneficial effects: The composite solvent of this invention achieves supramolecular recognition, with H2O2 and ethanol forming a 1:2 supramolecular structure. The diameter of the supramolecular cavity is similar to that of SO4. 2- Highly adaptable, selectivity coefficient: α(SO4) 2- / Cl - Up to 120, supramolecular structure and SO4 2- Complexation and directed catalysis to produce SO4· - Free radicals generate Na₂SO₄·10H₂O crystals, thus realizing SO₄²⁻. 2- High removal rate, especially suitable for SO4 2- High-impurity deep-well salt mines with a concentration >1.5g / L.

[0018] Meanwhile, SO4 2- After H2O2 and ethanol form a 1:2 supramolecular complex, the ethanol is oxidized in situ to HSO4 by H2O2. - It is transformed into Na2SO4·10H2O crystals through crystallization, compared with the traditional lime-soda ash process, which first produces SO4. 2- Oxidized to SO4· -Adding alkali further generates CaSO4 precipitate, optimizing the reaction pathway and significantly improving the simultaneous SO4 precipitation. 2- Recovery rate.

[0019] Moreover, the prepared H3PW 12 O 40 @Aminated SiO2, releases W at pH<4 6+ Catalytic site; automatically deactivated at pH > 7 to prevent over-oxidation; SO42- is controlled by pH regulation. 2- Deep removal and high-purity recovery. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of a method for in-situ impurity ion replacement and synergistic recovery of symbiotic resources in deep salt mines according to the present invention. Detailed Implementation

[0021] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0022] The following disclosure provides many different embodiments or examples for implementing various structures of the invention. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the invention. Furthermore, reference numerals and / or letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, examples of various specific processes and materials are provided, but those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0023] This invention provides a composite solvent, comprising a solvent system, a catalytic system, and a stabilizing system. By mass percentage, the solvent system comprises: 30% H₂O₂, 65.2% ethanol, and 0.8% supramolecular template agent. The catalytic system consists of: 3% pH-responsive catalyst and 0.5% co-catalyst; The stabilizing system consists of: 0.3% sodium citrate and 0.2% disodium ethylenediaminetetraacetate.

[0024] The supramolecular template agent is sodium dodecylbenzenesulfonate, and the co-catalyst is Na2WO4.

[0025] pH-responsive catalyst made of H3PW 12 O 40 H3PW is loaded onto an amino-modified SiO2 support with a pore size of 4-6 nm and an aminosilane modification amount of 7-9 wt%. 12 O 40 The loading capacity is 12-13 wt%.

[0026] A method for preparing a composite solvent includes the following steps: ① Weigh out sodium dodecyl sulfonate in the above mass ratio and slowly add it to the corresponding mass of ethanol at 25-30℃, and age for 2-3 hours; ② Mix H2O2 with the product of step ① under nitrogen protection and gradually increase the temperature to 40-45℃ to construct a supramolecular structure. The specific processes for the supramolecular structure construction stage include: initial hydrogen bond network formation during the induction phase (temperature 15-20℃, stirring rate 200rpm, mixing time 2h); supramolecular structure expansion during the growth phase (temperature 25-30℃, stirring rate 400rpm, mixing time 1.5h); and structure immobilization during the stabilization phase (temperature 40-45℃, stirring rate 100rpm, mixing time 0.5h).

[0027] H₂O₂ and ethanol form a 1:2 supramolecular structure. A strong hydrogen bond is formed between the OH bond (proton donor) of H₂O₂ and the lone pair electrons (proton acceptor) of the O atom in ethanol. A weak hydrogen bond is formed between the OH bond (proton donor) of ethanol and the terminal O atom (proton acceptor) of H₂O₂. The supramolecular structure is as follows: .

[0028] Adding sodium dodecyl sulfate (SDBS) forms a micelle encapsulation structure, which improves the stability of the supramolecular structure.

[0029] SO4 2- Selective entry into supramolecular cavities via size-matching effect enhances SO42- content. 2- The removal rate is ≥90%, and the selectivity coefficient for Cl⁻ is >100.

[0030] Specifically, the supramolecular cavity size (0.38 nm) and SO4 2- The ion diameter (0.46 nm) matching degree reached 82%, and Na + / K + The diameters are 0.19 nm and 0.27 nm, respectively, with a matching degree of <50%, while the supramolecular surface is resistant to SO4. 2- The electrostatic adsorption energy (-45.6 kJ / mol) is much higher than that for Cl.- Electrostatic adsorption energy (-12.3 kJ / mol), while hydrogen peroxide and ethanol simultaneously adsorb highly active SO4· - Transformed into more stable HSO4 - HSO4 - The solubility of SO4 is greatly reduced within the system, thus achieving SO4 2- Highly selective separation.

[0031] ③ Add pH-responsive catalyst H3PW 12 O 40 @Aminated SiO2 and corresponding mass of Na2WO4 are mixed, and then corresponding mass of sodium citrate and disodium ethylenediaminetetraacetate are added. After mixing for 2 hours, the mixture is dynamically aged for 24 hours to obtain a composite solvent.

[0032] Sodium citrate and Ca 2+ and Mg 2+ The Ca content in the system is reduced through a chelation-displacement reaction. 2+ and Mg 2+ content.

[0033] Furthermore, the pH-responsive catalyst H3PW 12 O 40 The preparation process of aminated SiO2 is as follows: ① The SiO2 support was modified with amino groups using 3-aminopropyltriethoxysilane to obtain aminated SiO2; Commercially available SiO2 was used, which was acid-washed, roasted and activated, and then vacuum dehydrated to obtain purified SiO2.

[0034] Specifically, the pickling conditions are: 5% HNO3 solution, reflux at 80°C for 6 hours (to remove metal impurities). Calcination procedure: 550℃ / 4h, heating rate 5℃ / min; Dehydration treatment: Vacuum drying at 120℃ with a vacuum degree of 0.1MPa until the moisture content is ≤0.1wt%, to obtain purified SiO2.

[0035] The purified SiO2 was expanded by hydrothermal expansion method. The specific steps are as follows: SiO2: cetyltrimethylammonium bromide (CTAB): NH4OH molar ratio of 1:0.3:0.1, hydrothermally heated at 110℃ for 24h, and dried at 550℃ to obtain SiO2 with pore size of 4-6nm.

[0036] 8 wt% aminopropyltriethoxysilane was added to toluene, followed by expanded SiO2, with a toluene / SiO2 ratio of 10:1 (v / w). The mixture was refluxed at 110°C under nitrogen protection for 6 h with a stirring speed of 300 rpm, and then Soxhlet extracted for 24 h (ethanol as solvent) to remove physical adsorption, yielding aminated SiO2.

[0037] ② H3PW was loaded into the pores of aminated SiO2 by impregnation method. 12 O 40 ; Specifically, H3PW 12 O 40 Dispersed in an aqueous ethanol solution (ethanol / water mass ratio = 7:3), at a concentration of 0.1 mol / L, H3PW is obtained. 12 O 40 Solution: Aminated SiO2 was placed in the solution, SiO2:solution = 1g:10mL, and dispersed by ultrasonic assistance (40kHz, 300W) for 30min. After standing at 25℃ for 12h, the solution was cycled and impregnated 8 times to obtain a wet catalyst with a loading of 12-13wt%.

[0038] ③ After vacuum encapsulation, microwave-UV synergistic activation is performed to obtain H3PW. 12 O 40 @Aminated SiO2.

[0039] Specifically, the wet catalyst was dried under a vacuum gradient at a vacuum level of 0.095 MPa, with the following temperature and isothermal conditions: room temperature / 2h → 60℃ / 4h → 80℃ / 2h, resulting in a final moisture content of ≤0.05%. Specifically, the activation process involves: microwave power of 300W, pulsed operation (5s on / 5s off), ultraviolet wavelength of 254nm, and a concentration of 15mW / cm². 2 Microwave activation for 5 seconds, pause for 2 seconds, UV activation for 5 seconds, pause for 3 seconds, and repeat this alternating cycle for 30 minutes to finally obtain H3PW. 12 O 40 @Aminated SiO2, defect state W 5+ / W 6+ The ratio is 0.15.

[0040] Understandably, the heteropolyacid structure (Keggin) [PW] 12 O 40 ] 3- The W=O bond in the solution, under acidic conditions: W=O + H + → W-OH + (Brønsted acid site); Under alkaline conditions: W = O + OH - → W-OOH (passivated state). Simultaneously, the silanol groups (Si-OH) on the SiO2 surface protonate at pH < 4 to form Si-OH2. + Promotes the release of heteropoly acids; deprotonation (Si-O) occurs at pH > 7. - This leads to heteropolyacid binding.

[0041] Therefore, under acidic conditions (pH 2.5-4.5), the effect on SO42- is... 2- It undergoes oxidation, transforming into the more stable HSO4. - This reduces solubility. The specific reaction is as follows: H3PW 12 O 40 + 3H + → [PW 12 O 40 ] 3- ·3H + ; [PW 12 O 40 ] 3- ·3H + + SO4 2- → [PW 12 O 40 SO4 5- + 2H + ; [PW 12 O 40 SO4 5- → [PW 12 O 40 ] 3- + SO4· - ; Under alkaline conditions (pH > 7.0), there is no catalytic activity, so excessive oxidation should be avoided. The specific reaction is as follows: [[PW 12 O 40 ] 3- ] +OH - → [PW 11 O 39 ] 7- + WO4 2- .

[0042] A method for in-situ impurity ion replacement and synergistic resource recovery in deep-well salt mines involves injecting the aforementioned composite solvent through a three-stage injection system, including the following steps: ① Wellbore: Preheat to 50±2℃, inject pH adjuster (dilute HCl) to lower the pH of the brine to 3.5-4.0; ②Reaction chamber: Controlled pressure 1.2-1.8 MPa, pumped by a high-pressure pump at 8-12 m³ / h 3 The composite solvent is injected at a flow rate of / h, wherein the catalyst loading is 0.6 kg / m³. 3 brine; Specifically, H2O2 and ethanol form a 1:2 supramolecular structure, and the diameter of the supramolecular cavity is similar to that of SO4. 2- Highly compatible with SO42- Recognizes complexes and generates SO4· through in-situ catalysis of H2O2 with the catalyst. - Free radicals, and H3PW 12 O 40 @Aminated SiO2 releases W at pH < 4 6+ Catalytic site; automatically deactivated at pH > 7 to prevent over-oxidation and achieve SO4 oxidase. 2- Integrated complexation-in-situ oxidation-crystallization for deep removal. ③ Wellbore separation section: Gradient cooling crystallization to generate Na2SO4·10H2O, achieving SO4 removal. 2- High-purity recovery.

[0043] Specifically, in the primary cooling zone, the temperature is lowered from 60℃ to 45℃ at a rate of 0.5±0.05℃ / min, with a residence time of 30 min, to promote the formation of Na2SO4·10H2O crystal nuclei; in the secondary crystallization zone, the temperature is lowered from 45℃ to 30℃ at a rate of 0.3±0.03℃ / min, with a residence time of 45 min, to promote crystal growth; and in the tertiary ripening zone, the temperature is lowered from 30℃ to 15℃ at a rate of 0.2±0.02℃ / min, with a residence time of 60 min, to promote crystal densification and reduce Cl- inclusions. - This improves the purity of Na2SO4·10H2O.

[0044] In summary, this invention provides a method for in-situ impurity ion replacement and synergistic resource recovery in deep-well salt mines. The composite solvent of this invention utilizes supramolecular recognition, allowing H2O2 and ethanol to form a 1:2 supramolecular structure. The supramolecular cavity diameter is similar to that of SO4. 2- Highly adaptable, selectivity coefficient: α(SO4) 2- / Cl - Up to 120, supramolecular structure and SO4 2- Complexation, in-situ catalytic production of SO4· - Free radicals generate Na₂SO₄·10H₂O crystals. The reaction pathway was optimized to achieve SO₄²⁻ production. 2- High removal rate and SO4 2- High-purity recovery. H3PW was also prepared simultaneously. 12 O 40 @Aminated SiO2, releases W at pH<4 6+ Catalytic site; automatically passivates and deactivates at pH > 7 to prevent over-oxidation, achieving SO4 catalysis through the synergy of supramolecular recognition and pH-intelligent response. 2- Deep removal and high-purity recovery.

[0045] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A method for in-situ impurity ion replacement and synergistic recovery of symbiotic resources in deep-well salt mines, characterized in that, Includes the following steps: ① Weigh out 30% H2O2, 65.2% ethanol, 0.8% supramolecular template agent, 3% pH-responsive catalyst, 0.5% co-catalyst, 0.3% sodium citrate and 0.2% disodium ethylenediaminetetraacetate according to the mass percentage to prepare a composite solvent; ② The high-concentration sulfur-containing brine is initially filtered to obtain filtrate. A pH adjuster (dilute HCl) is injected to lower the pH of the filtrate to 3.5-4.0, and the wellbore is preheated to 50±2℃. ③ The composite solvent is dispensed using a high-pressure pump (1.5-2.0 MPa) at a rate of 8-12 m³ / min. 3 Injecting SO4 into the deep well cavity at a flow rate of / h, setting the pressure in the reaction section of the cavity to 1.2-1.8 MPa, and the reaction time to 2-3 hours, using a composite solvent to treat SO4. 2- Complexation and in-situ oxidation are performed to transform SO4 2- Converted to HSO4 - ④ After the reaction is complete, a gradient temperature parameter is set in the wellbore separation section. HSO4 is then crystallized through gradient cooling. - It is converted into Na2SO4·10H2O crystals to achieve SO42- 2- Removal and recycling.

2. The method for in-situ impurity ion replacement and synergistic recovery of symbiotic resources in deep-well salt mines according to claim 1, characterized in that: The separation section is set with three temperature gradients: a primary cooling zone (60℃-45℃), a secondary crystallization zone (45℃-30℃), and a tertiary ripening zone (30℃-15℃).

3. The method for in-situ impurity ion replacement and synergistic recovery of symbiotic resources in deep-well salt mines according to claim 2, characterized in that: The cooling rates of the primary cooling zone, the secondary crystallization zone, and the tertiary ripening zone were 0.5±0.05 ℃ / min, 0.3±0.03 ℃ / min, and 0.2±0.02 ℃ / min, respectively.

4. The method for in-situ impurity ion replacement and synergistic resource recovery in deep-well salt mines according to claim 1, characterized in that: The pH-responsive catalyst is specifically H3PW. 12 O 40 @Aminated SiO2, with a Keggin structure, H3PW 12 O 40 The loading amount is 12-13 wt%, and the pore size of the aminated SiO2 support is 4-6 nm.

5. The method for in-situ impurity ion replacement and synergistic resource recovery in deep-well salt mines according to claim 1, characterized in that: The preparation of the composite solvent includes the following steps: ① Weigh out 0.8% sodium dodecyl sulfonate and slowly add it to 65.2% ethanol at 25-30℃, and age for 2-3 hours; ② Under nitrogen protection, 30% by mass of H2O2 was mixed with the product of step ①, and the temperature was gradually increased to 40-45℃ to construct a supramolecular structure; ③ Add 3% by mass of pH-responsive catalyst H3PW 12 O 40 @Aminated SiO2 and 0.5% Na2WO4 were mixed, and then 0.3% sodium citrate and 0.2% disodium ethylenediaminetetraacetate were added. After mixing for 2 hours, the mixture was dynamically aged for 24 hours to obtain a composite solvent.

6. The method for in-situ impurity ion replacement and synergistic recovery of symbiotic resources in deep-well salt mines according to claim 5, characterized in that: The supramolecular structure is specifically a 1:2 supramolecular structure formed by H2O2 and ethanol, with the following specific structural formula: 。 7. The method for in-situ impurity ion replacement and synergistic recovery of symbiotic resources in deep-well salt mines according to claim 1, characterized in that: The pH-responsive catalyst was added at a rate of 0.6 kg / m³. 3 brine.

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