Recycling multi-stage treatment method for copper-containing solid waste

Abstract

The invention discloses a recycling multi-stage treatment method for copper-containing solid waste, and belongs to the technical field of recycling treatment of the copper-containing solid waste. The recycling multi-stage treatment method for the copper-containing solid waste comprises the following steps: (1) crushing the copper-containing solid waste to obtain pretreated copper-containing solid waste; (2) the pretreated copper-containing solid waste is added into a leaching agent and stirred, and a leaching solution and solid-phase residues are separated through a filter press; (3) adding an organic complexing agent into the leachate, stirring, carrying out solid-liquid separation to obtain a precipitate and a first waste liquid, carrying out washing, filter pressing and drying on the precipitate to obtain a copper-containing substance, and extracting and refining the copper-containing substance to obtain metal copper and a second waste liquid; (4) mixing the first waste liquid and the second waste liquid, and filtering to obtain dischargeable water; and (5) adding a stabilizer into the solid-phase residues, heating and stirring to obtain a solidified body. The method can effectively improve the copper recovery rate and reduce environmental pollution.

Description

Technical Field

[0001] The present invention belongs to the technical field of resource recovery treatment of copper-containing solid waste, and particularly relates to a multi-stage resource recovery treatment method for copper-containing solid waste. Background Art

[0002] With the acceleration of global industrialization, large quantities of copper-containing solid waste are continuously generated in fields such as metal smelting, electronics manufacturing, and chemical production. The complexity and diversity of copper-containing solid wastes increase the difficulty of their treatment. These wastes contain not only copper but also potentially harmful elements such as lead, zinc, cadmium, and mercury. If released directly into the environment, these elements will accumulate through the food chain, causing long-term harm to ecosystems and human health. In addition, the varying physical and chemical properties of copper-containing solid wastes, such as copper sulfide minerals such as chalcopyrite, bornite, and chalcocite, as well as gangue minerals such as quartz, feldspar, and mica, require comprehensive consideration of multiple factors during their treatment.

[0003] Against this backdrop, research into multi-stage treatment methods for the resource recovery of copper-containing solid waste is particularly important. This approach aims to transform copper-containing solid waste into a reusable resource through scientific, efficient, and environmentally friendly means, reducing environmental pollution and achieving sustainable resource utilization. This research not only aligns with current global trends in environmental protection and sustainable development but also represents a crucial approach to addressing the problem of copper-containing solid waste disposal.

[0004] Patent CN 116282716 A discloses a method for resource utilization of copper-containing waste residue. This method involves adding copper-containing waste residue to acidic mine water, slurrying, and then flocculating and thickening the residue to produce a de-ironing underflow and a de-ironing overflow. The de-ironing underflow is mixed with a neutralization overflow, washed, and then dewatered by filtration to produce a first press filtrate and a first press residue that meets the requirements of general industrial solid waste. The first press filtrate and the de-ironing overflow are then subjected to a sulfidation treatment to recover copper, producing a sulfided overflow, a second press filtrate, and a second press residue that can be collected as copper slag. The sulfided overflow and second press filtrate are then neutralized to produce a neutralized overflow that meets emission standards, a third press filtrate, and a third press residue that meets the requirements of general industrial solid waste. This method can utilize acidic mine water to treat copper-containing waste residue, achieving deep purification of the mine acidic water. However, this method does not treat or collect copper-containing substances, and wastewater treatment still has room for improvement. Summary of the Invention

[0005] The purpose of the present invention is to provide a multi-stage treatment method for resource recovery of copper-containing solid waste, which is used to solve the technical problems in the prior art of low recovery rate of copper-containing substances in copper-containing solid waste and poor treatment effect of wastewater generated during the treatment process.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] The present invention provides a multi-stage resource treatment method for copper-containing solid waste, comprising the following steps:

[0008] Step (1): crushing the copper-containing solid waste into small particles, removing large impurities by screening, removing ferromagnetic materials by magnetic separation, and removing light materials by air separation to obtain pretreated copper-containing solid waste;

[0009] Step (2): adding the pretreated copper-containing solid waste to the leaching agent, stirring, and separating the leachate and the solid residue by a filter press;

[0010] Step (3): adding an organic complexing agent to the leachate, stirring, and solid-liquid separation to obtain a precipitate and a first waste liquid, washing the precipitate, filter pressing, and drying to obtain a copper-containing substance, and extracting and refining the copper-containing substance to obtain metallic copper and a second waste liquid;

[0011] Step (4): mixing the first waste liquid and the second waste liquid to obtain a mixed waste liquid, filtering the mixed waste liquid to obtain dischargeable water;

[0012] Step (5): adding a stabilizer to the solid phase residue, heating, and stirring to obtain a solidified body.

[0013] Preferably, in step (2), the leaching agent is composed of one or more combinations of sulfuric acid, nitric acid, hydrochloric acid, ammonia water, sodium carbonate, sodium hydroxide and sodium chloride.

[0014] Preferably, the preparation method of the organic complexing agent comprises the following steps:

[0015] Q1: Toluene was added to a container containing carbon tetrachloride, followed by addition of N-bromosuccinimide and benzoyl peroxide. The mixture was heated to reflux, cooled, filtered, washed, dried, and rotary evaporated to obtain intermediate 1.

[0016] Q2: Sodium bicarbonate, dichloromethane, distilled water, tetrabutylammonium iodide and intermediate 1 are added to a container, heated to reflux, and N-hydroxypeptide imide is added to the container. After reflux, the mixture is cooled, separated, and the aqueous layer is extracted. The organic phases are combined, washed, dried, and filtered to obtain intermediate 2;

[0017] Q3: Add intermediate 2 and concentrated hydrochloric acid to a container, heat under reflux, cool to room temperature, and filter to obtain a white solid and a filtrate. The filtrate is concentrated under reduced pressure to obtain a white solid. The white solid is washed and distilled to obtain intermediate 3.

[0018] Q4: Under nitrogen protection, lithium diisopropylamine was added to a round-bottom flask. At low temperature, 3-picoline was added and stirred to obtain a mixed solution. Ethyl 1-adamantanecarboxylate was then added and stirred continuously. The organic phase was washed, dried, distilled, and purified to obtain organic compound 1.

[0019] Q5: Add intermediate 3 to pyridine containing organic matter 1, reflux reaction, add distilled water to the reaction mixture after completion of the reaction, extract, wash the organic phase, dry, distill under reduced pressure, and purify to obtain an organic complexing agent.

[0020] In the above process, benzoyl peroxide is decomposed by heat, and the generated free radicals attack the methyl hydrogen of toluene to generate methyl free radicals and hydrogen bromide. The toluene free radical then reacts with N-bromosuccinimide to generate intermediate 1. Then, under the condition of tetrabutylammonium iodide as a phase transfer catalyst, N-hydroxypeptide imide and intermediate 1 undergo a substitution reaction to generate intermediate 2. Intermediate 2 undergoes a hydrolysis reaction under the action of concentrated hydrochloric acid to obtain intermediate 3. Under nitrogen protection, lithium diisopropylamine and 3-methylpyridine undergo a substitution reaction at low temperature, and then continue to react with 1-adamantane hexanoic acid ethyl ester to obtain organic matter 1. Then, organic matter 1 reacts with intermediate 3 to prepare an organic complexing agent.

[0021] Preferably, in Q1, the molar ratio of toluene, N-bromosuccinimide and benzoyl peroxide is (6-12): (7-14): (0.2-0.4), the heating reflux temperature is 70-80 ° C, the reflux time is 3-5h, washed with 5wt% sodium bicarbonate solution and ice water, and dried with anhydrous magnesium sulfate; in Q2, sodium bicarbonate, dichloromethane, distilled water, tetrabutylammonium iodide, intermediate 1 and N-hydroxy The dosage ratio of peptide imide is (6-9) g: (30-45) mL: (50-75) mL: (3-4.5) g: (6-9) g: (5-7.5) g, the heating reflux temperature is 55-65° C., the time for adding N-hydroxypeptidimide is 30-45 minutes, the reflux time is 2-4 hours, extraction is performed with dichloromethane, washing is performed with 5wt% sodium bicarbonate solution and distilled water, and drying is performed with anhydrous magnesium sulfate.

[0022] Preferably, in Q3, the ratio of intermediate 2 to concentrated hydrochloric acid is (3-6) g: (20-40) mL, the heating reflux temperature is 70-90° C., the time is 3-5 h, and the white solid is washed with acetonitrile.

[0023] Preferably, in Q4, the molar ratio of lithium diisopropylamine, 3-methylpyridine and 1-adamantanecarboxylic acid ethyl ester is (1.7-2.2): (1.8-2.4): (1-1.3), the low temperature is 0-1°C, the stirring time is 1-2h, the stirring time is continued for 3-5h, the product is washed with saturated sodium chloride, extracted with ethyl acetate, the organic phase is washed with distilled water 3-5 times, dried with anhydrous sodium sulfate, and purified with a mixed solution of petroleum ether and ethyl acetate in a volume ratio of 5:1 as an eluent; in Q5, the amount ratio of organic matter 1, intermediate 3 and distilled water is (3-6) mL: (0.65-1.3) g: (10-20) mL, the reflux time is 3-4h, the product is extracted with dichloromethane, the organic phase is washed with distilled water, dried with anhydrous sodium sulfate, and purified with a mixed solution of petroleum ether and ethyl acetate in a volume ratio of 7:1 as an eluent.

[0024] Preferably, in step (4), the mixed waste liquid is filtered using a chitosan composite membrane, and the preparation method of the chitosan composite membrane comprises the following steps:

[0025] S1: Chitosan is dissolved in glacial acetic acid, then diluted with anhydrous ethanol and placed in an ultrasonic cleaner, followed by adding benzaldehyde, heating and shaking to obtain a mixed chitosan solution;

[0026] S2: adding carbon disulfide and sodium hydroxide solution to the mixed chitosan solution, stirring at room temperature, heating to react, then adding hydrochloric acid to adjust the pH, and heating to react to obtain modified chitosan;

[0027] S3: Glutaraldehyde solution and ethanol are mixed evenly and added to a polytetrafluoroethylene reactor. After heating for reaction, the mixture is cooled and rotary evaporated to obtain a viscous liquid. The viscous liquid and modified chitosan are mixed and stirred, and then transferred to a mold. After rapid freezing under liquid nitrogen, the mixture is placed in a freeze dryer and then heated for reaction to obtain a chitosan composite film.

[0028] In the above process, chitosan first reacts with benzaldehyde to obtain a mixed chitosan solution, then a xanthate group is added to the C6 hydroxyl group of the product, and then the imine is converted into a primary amine by acid hydrolysis with hydrochloric acid to prepare a modified chitosan; then, using glutaraldehyde solution and ethanol as raw materials, a viscous liquid is obtained by a solvent thermal method, and the liquid is mixed with the modified chitosan to prepare a chitosan composite membrane.

[0029] Preferably, in S1, the dosage ratio of chitosan, glacial acetic acid, anhydrous ethanol and benzaldehyde is (1-1.5) g: (20-30) mL: (20-30) mL: (0.013-0.019) mL, the volume fraction of glacial acetic acid is 3vt%, the heating and shaking temperature is 70-80°C, and the time is 4-6h.

[0030] Preferably, in S2, the mixed chitosan solution, carbon disulfide and sodium hydroxide solution are used in a ratio of (10-15) mL: (2-3) mL: (50-75) mL, the mass fraction of the sodium hydroxide solution is 5 wt%, the stirring time is 30-45 min, the temperature of the reaction is 40-50 ° C, the time is 3-4 h, the concentration of hydrochloric acid is 1 mol / L, and the pH is adjusted to 9-10.

[0031] Preferably, in S3, the volume ratio of glutaraldehyde solution and ethanol is (15-30): (30-60), the volume fraction of glutaraldehyde solution is 5vt%, the heating reaction temperature is 150-160°C, the time is 2-3h, the rotary evaporation temperature is 40-50°C, the time is 4-6h, the amount ratio of viscous liquid and modified chitosan is (10-12)mL: (8-10)g, the mixing and stirring time is 10-15min, placed in a freeze dryer for 10-12h, the heating reaction temperature is 60-70°C, and the reaction time is 4-6h.

[0032] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0033] 1. The present invention first uses toluene, N-bromosuccinimide, N-hydroxyphthalimide, 3-picoline and 1-adamantanecarboxylic acid ethyl ester as raw materials to prepare an organic complex, and adds the substance to a leachate to effectively adsorb copper ions in the leachate, so that metallic copper is obtained. Subsequently, chitosan, benzaldehyde, carbon disulfide, sodium hydroxide, glutaraldehyde and ethanol are used as raw materials to prepare a chitosan composite membrane, and the chitosan composite membrane is applied to a filtration process of a mixed waste liquid to effectively adsorb heavy metal ions in the mixed waste liquid, thereby making the waste liquid meet the discharge standard and reducing the generation of polluted wastewater.

[0034] 2. The present invention uses toluene, N-bromosuccinimide, N-hydroxyphthalimide, 3-methylpyridine and 1-adamantanecarboxylic acid ethyl ester as raw materials to prepare an organic complex. The organic complex undergoes a complexation reaction with copper ions in a leachate. In the complexation reaction, nitrogen atoms and oxygen atoms in the pyridoxime group of the organic complex have lone pairs of electrons, which can form coordination bonds with empty orbitals of the copper ions. With the formation of the coordination bonds, the copper ions are firmly fixed in the complexing agent molecules to be precipitated, thereby extracting copper-containing substances from the leachate. Metallic copper is then obtained through extraction and refining, thereby improving the recovery rate of copper.

[0035] 3. The present invention uses chitosan, benzaldehyde, carbon disulfide, sodium hydroxide, glutaraldehyde and ethanol as raw materials to prepare a chitosan composite membrane. The chitosan composite membrane contains abundant active groups, such as amino, hydroxyl and xanthate groups. These groups can undergo strong coordination or electrostatic adsorption with heavy metal ions in the mixed waste liquid, effectively removing heavy metal ions in the waste liquid. The porous structure and high specific surface area of ​​the chitosan composite membrane can further enhance its adsorption capacity, so that more heavy metal ions can be trapped in the membrane and on the membrane surface, thereby making the tail water meet the discharge standard. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0037] Figure 1 The present invention is a flow chart of a multi-stage method for resource-based treatment of copper-containing solid waste. DETAILED DESCRIPTION

[0038] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0039] Example 1: This example discloses a method for preparing an organic complexing agent, comprising the following steps:

[0040] Q1: 15.72 mL of toluene was added to a container containing 40 mL of carbon tetrachloride, followed by the addition of 30.89 g of N-bromosuccinimide and 1.2 g of benzoyl peroxide. The mixture was heated at 75°C for 5 h, cooled and filtered, washed with 5 wt% sodium bicarbonate solution and ice water, dried over anhydrous magnesium sulfate, and rotary evaporated to obtain intermediate 1.

[0041] Q2: 7.5 g of sodium bicarbonate, 37.5 mL of dichloromethane, 62.5 mL of distilled water, 3.75 g of tetrabutylammonium iodide and 7.5 g of intermediate 1 were added to a container, heated to reflux at 60°C, and 6.25 g of N-hydroxypeptide imide was added to the container within 30 minutes. After reflux for 3 hours, the mixture was cooled, separated, and the aqueous layer was extracted with dichloromethane. The organic phases were combined, washed with 5 wt% sodium bicarbonate solution and distilled water, dried over anhydrous magnesium sulfate, and filtered to obtain intermediate 2;

[0042] Q3: 4.5 g of intermediate 2 and 30 mL of concentrated hydrochloric acid were added to a container, heated under reflux at 80°C for 4 h, cooled to room temperature, and filtered to obtain a white solid and a filtrate. The filtrate was concentrated under reduced pressure to obtain a white solid, which was washed with acetonitrile and distilled to obtain intermediate 3.

[0043] Q4: Under nitrogen protection, 1.22 g of lithium diisopropylamine was added to a round-bottom flask. At 0°C, 1.16 mL of 3-picoline was added and stirred for 1 h to obtain a mixed solution. Subsequently, 1.37 g of 1-adamantanecarboxylic acid ethyl ester was added and stirring was continued for 5 h. The mixture was washed with saturated sodium chloride and extracted with ethyl acetate. The organic phase was washed five times with distilled water, dried over anhydrous sodium sulfate, and distilled. Purification was performed using a mixed solution of petroleum ether and ethyl acetate in a volume ratio of 5:1 as the eluent to obtain organic compound 1.

[0044] Q5: 0.93 g of intermediate 3 was added to 5 mL of pyridine containing 4.5 mL of organic matter 1, and the reaction was refluxed for 4 h. After the reaction was completed, 15 mL of distilled water was added to the reaction mixture, and the mixture was extracted with dichloromethane. The organic phase was washed with distilled water, dried over anhydrous sodium sulfate, and distilled under reduced pressure. The organic complexing agent was purified using a mixed solution of petroleum ether and ethyl acetate in a volume ratio of 7:1 as the eluent to obtain the organic complexing agent.

[0045] This embodiment discloses a method for preparing a chitosan composite film, comprising the following steps:

[0046] S1: 1.25 g of chitosan was dissolved in 25 mL of 3% glacial acetic acid, then diluted with 25 mL of anhydrous ethanol and placed in an ultrasonic cleaner. 0.016 mL of benzaldehyde was then added and heated at 75°C for 4 h to obtain a mixed chitosan solution.

[0047] S2: To 12.5 mL of the mixed chitosan solution, 2 mL of carbon disulfide and 62.5 mL of a 5 wt% sodium hydroxide solution were added. The mixture was stirred at room temperature for 45 min and then reacted at 50°C for 4 h. 1 mol / L hydrochloric acid was then added to adjust the pH to 9. The mixture was reacted at 35°C for 1.5 h to obtain modified chitosan.

[0048] S3: 27.5 mL of 5% glutaraldehyde solution and 45 mL of ethanol were mixed evenly and added to a polytetrafluoroethylene reactor. The mixture was heated at 155°C for 3 h, cooled, and rotary evaporated at 45°C for 6 h to obtain a viscous liquid. 11 mL of the viscous liquid and 9 g of modified chitosan were mixed and stirred for 15 min, transferred to a mold, quickly frozen under liquid nitrogen, placed in a freeze dryer for 12 h, and then heated at 70°C for 6 h to obtain a chitosan composite film.

[0049] See Figure 1 This embodiment discloses a multi-stage resource treatment method for copper-containing solid waste, comprising the following steps:

[0050] Step (1): crushing the copper-containing solid waste into small particles, removing large impurities by screening, removing ferromagnetic materials by magnetic separation, and removing light materials by air separation to obtain pretreated copper-containing solid waste;

[0051] Step (2): adding the pretreated copper-containing solid waste to sulfuric acid, stirring, and separating the leachate and the solid residue by a filter press;

[0052] Step (3): adding an organic complexing agent to the leachate, stirring, and solid-liquid separation to obtain a precipitate and a first waste liquid, washing the precipitate, filter pressing, and drying to obtain a copper-containing substance, and extracting and refining the copper-containing substance to obtain metallic copper and a second waste liquid;

[0053] Step (4): mixing the first waste liquid and the second waste liquid to obtain a mixed waste liquid, and filtering the mixed waste liquid using a chitosan composite membrane to obtain dischargeable water;

[0054] Step (5): adding a stabilizer to the solid phase residue, heating, and stirring to obtain a solidified body.

[0055] Example 2: This example discloses a method for preparing an organic complexing agent, comprising the following steps:

[0056] Q1: 10.48 mL of toluene was added to a container containing 40 mL of carbon tetrachloride, followed by the addition of 41.18 g of N-bromosuccinimide and 0.8 g of benzoyl peroxide. The mixture was heated at 75°C for 5 h, cooled and filtered, washed with 5 wt% sodium bicarbonate solution and ice water, dried over anhydrous magnesium sulfate, and rotary evaporated to obtain intermediate 1.

[0057] Q2: 9 g of sodium bicarbonate, 45 mL of dichloromethane, 50 mL of distilled water, 4.5 g of tetrabutylammonium iodide and 6 g of intermediate 1 were added to a container, heated to reflux at 60°C, and 5 g of N-hydroxypeptide imide was added to the container within 30 minutes. After reflux for 3 hours, the mixture was cooled, separated, and the aqueous layer was extracted with dichloromethane. The organic phases were combined, washed with 5 wt% sodium bicarbonate solution and distilled water, dried over anhydrous magnesium sulfate, and filtered to obtain intermediate 2;

[0058] Q3: 3 g of intermediate 2 and 40 mL of concentrated hydrochloric acid were added to a container, heated under reflux at 80°C for 4 h, cooled to room temperature, and filtered to obtain a white solid and a filtrate. The filtrate was concentrated under reduced pressure to obtain a white solid, which was washed with acetonitrile and distilled to obtain intermediate 3.

[0059] Q4: Under nitrogen protection, 1.38 g of lithium diisopropylamine was added to a round-bottom flask. At 0°C, 1.33 mL of 3-methylpyridine was added and stirred for 1 h to obtain a mixed solution. Subsequently, 1.19 g of ethyl 1-adamantanecarboxylate was added and stirring was continued for 5 h. The mixture was washed with saturated sodium chloride and extracted with ethyl acetate. The organic phase was washed five times with distilled water, dried over anhydrous sodium sulfate, and distilled. Purification was performed using a mixed solution of petroleum ether and ethyl acetate in a volume ratio of 5:1 as the eluent to obtain organic compound 1.

[0060] Q5: 0.65 g of intermediate 3 was added to 6.5 mL of pyridine containing 6 mL of organic matter 1, and the reaction was refluxed for 4 h. After the reaction was completed, 20 mL of distilled water was added to the reaction mixture, and the mixture was extracted with dichloromethane. The organic phase was washed with distilled water, dried over anhydrous sodium sulfate, and distilled under reduced pressure. The organic phase was purified using a mixed solution of petroleum ether and ethyl acetate in a volume ratio of 7:1 as an eluent to obtain an organic complexing agent.

[0061] This embodiment discloses a method for preparing a chitosan composite film, comprising the following steps:

[0062] S1: 1.5 g of chitosan was dissolved in 30 mL of 3% glacial acetic acid, then diluted with 28 mL of anhydrous ethanol and placed in an ultrasonic cleaner. 0.013 mL of benzaldehyde was then added and heated at 75°C for 4 h to obtain a mixed chitosan solution.

[0063] S2: To 10 mL of the mixed chitosan solution, 2.5 mL of carbon disulfide and 50 mL of a 5 wt% sodium hydroxide solution were added, stirred at room temperature for 45 min, reacted at 50°C for 4 h, and then 1 mol / L hydrochloric acid was added to adjust the pH to 9. The mixture was reacted at 35°C for 1.5 h to obtain modified chitosan.

[0064] S3: Mix 15 mL of 5% glutaraldehyde solution and 30 mL of ethanol evenly and add them to a polytetrafluoroethylene reactor. Heat and react at 155°C for 3 hours, cool, and rotary evaporate at 45°C for 6 hours to obtain a viscous liquid. Mix 10 mL of the viscous liquid and 8 g of modified chitosan and stir for 15 minutes. Transfer it to a mold, quickly freeze it under liquid nitrogen, place it in a freeze dryer for 12 hours, and then heat and react at 70°C for 6 hours to obtain a chitosan composite film.

[0065] See Figure 1 This embodiment discloses a multi-stage resource treatment method for copper-containing solid waste, comprising the following steps:

[0066] Step (1): crushing the copper-containing solid waste into small particles, removing large impurities by screening, removing ferromagnetic materials by magnetic separation, and removing light materials by air separation to obtain pretreated copper-containing solid waste;

[0067] Step (2): adding the pretreated copper-containing solid waste to sulfuric acid, stirring, and separating the leachate and the solid residue by a filter press;

[0068] Step (3): adding an organic complexing agent to the leachate, stirring, and solid-liquid separation to obtain a precipitate and a first waste liquid, washing the precipitate, filter pressing, and drying to obtain a copper-containing substance, and extracting and refining the copper-containing substance to obtain metallic copper and a second waste liquid;

[0069] Step (4): mixing the first waste liquid and the second waste liquid to obtain a mixed waste liquid, and filtering the mixed waste liquid using a chitosan composite membrane to obtain dischargeable water;

[0070] Step (5): adding a stabilizer to the solid phase residue, heating, and stirring to obtain a solidified body.

[0071] Example 3: This example discloses a method for preparing an organic complexing agent, comprising the following steps:

[0072] Q1: Add 20.96 mL of toluene to a container containing 40 mL of carbon tetrachloride, followed by 20.59 g of N-bromosuccinimide and 1.6 g of benzoyl peroxide. Heat under reflux at 75°C for 5 h, cool and filter, wash with 5 wt% sodium bicarbonate solution and ice water, dry over anhydrous magnesium sulfate, and rotary evaporate to obtain intermediate 1.

[0073] Q2: 6 g of sodium bicarbonate, 30 mL of dichloromethane, 75 mL of distilled water, 3 g of tetrabutylammonium iodide and 9 g of intermediate 1 were added to a container, heated to reflux at 60°C, and 7.5 g of N-hydroxypeptide imide was added to the container within 30 minutes. After reflux for 3 hours, the mixture was cooled, separated, and the aqueous layer was extracted with dichloromethane. The organic phases were combined, washed with 5 wt% sodium bicarbonate solution and distilled water, dried over anhydrous magnesium sulfate, and filtered to obtain intermediate 2;

[0074] Q3: 6 g of intermediate 2 and 20 mL of concentrated hydrochloric acid were added to a container, heated under reflux at 80°C for 4 h, cooled to room temperature, and filtered to obtain a white solid and a filtrate. The filtrate was concentrated under reduced pressure to obtain a white solid, which was washed with acetonitrile and distilled to obtain intermediate 3.

[0075] Q4: Under nitrogen protection, 1.06 g of lithium diisopropylamine was added to a round-bottom flask. At 0°C, 1.01 mL of 3-methylpyridine was added and stirred for 1 h to obtain a mixed solution. Subsequently, 1.55 g of ethyl 1-adamantanecarboxylate was added and stirring was continued for 5 h. The mixture was washed with saturated sodium chloride and extracted with ethyl acetate. The organic phase was washed five times with distilled water, dried over anhydrous sodium sulfate, and distilled. Purification was performed using a mixed solution of petroleum ether and ethyl acetate in a volume ratio of 5:1 as the eluent to obtain organic compound 1.

[0076] Q5: 1.3 g of intermediate 3 was added to 3.5 mL of pyridine containing 3 mL of organic matter 1, and the reaction was refluxed for 4 h. After the reaction was completed, 10 mL of distilled water was added to the reaction mixture, and the mixture was extracted with dichloromethane. The organic phase was washed with distilled water, dried over anhydrous sodium sulfate, and distilled under reduced pressure. The organic phase was purified using a mixed solution of petroleum ether and ethyl acetate in a volume ratio of 7:1 as the eluent to obtain an organic complexing agent.

[0077] This embodiment discloses a method for preparing a chitosan composite film, comprising the following steps:

[0078] S1: 1 g of chitosan was dissolved in 20 mL of 3% glacial acetic acid, then diluted with 22 mL of anhydrous ethanol and placed in an ultrasonic cleaner. 0.019 mL of benzaldehyde was then added and heated at 75°C for 4 h to obtain a mixed chitosan solution.

[0079] S2: To 15 mL of the mixed chitosan solution, 3 mL of carbon disulfide and 75 mL of a 5 wt% sodium hydroxide solution were added. The mixture was stirred at room temperature for 45 min and then reacted at 50°C for 4 h. 1 mol / L hydrochloric acid was then added to adjust the pH to 9. The mixture was reacted at 35°C for 1.5 h to obtain modified chitosan.

[0080] S3: Mix 30 mL of 5% by volume glutaraldehyde solution and 60 mL of ethanol, add them to a polytetrafluoroethylene reactor, heat at 155°C for 3 hours, cool, and rotary evaporate at 45°C for 6 hours to obtain a viscous liquid; mix 12 mL of the viscous liquid and 10 g of modified chitosan and stir for 15 minutes, transfer them to a mold, quickly freeze them under liquid nitrogen, place them in a freeze dryer for 12 hours, and then heat at 70°C for 6 hours to obtain a chitosan composite film.

[0081] See Figure 1 This embodiment discloses a multi-stage resource treatment method for copper-containing solid waste, comprising the following steps:

[0082] Step (1): crushing the copper-containing solid waste into small particles, removing large impurities by screening, removing ferromagnetic materials by magnetic separation, and removing light materials by air separation to obtain pretreated copper-containing solid waste;

[0083] Step (2): adding the pretreated copper-containing solid waste to sulfuric acid, stirring, and separating the leachate and the solid residue by a filter press;

[0084] Step (3): adding an organic complexing agent to the leachate, stirring, and solid-liquid separation to obtain a precipitate and a first waste liquid, washing the precipitate, filter pressing, and drying to obtain a copper-containing substance, and extracting and refining the copper-containing substance to obtain metallic copper and a second waste liquid;

[0085] Step (4): mixing the first waste liquid and the second waste liquid to obtain a mixed waste liquid, and filtering the mixed waste liquid using a chitosan composite membrane to obtain dischargeable water;

[0086] Step (5): adding a stabilizer to the solid phase residue, heating, and stirring to obtain a solidified body.

[0087] Comparative Example 1: Compared with Example 1, in Comparative Example 1, ethylenediaminetetraacetic acid is used instead of the organic complexing agent during the treatment of copper-containing solid waste, and other conditions remain unchanged.

[0088] Comparative Example 2: Compared with Example 1, in the process of treating copper-containing solid waste, Comparative Example 2 uses an ordinary filter membrane instead of the chitosan composite membrane, and other conditions remain unchanged.

[0089] Experimental Example: Based on GB 25467-2010 and GB 8978-1996, the dischargeable water was judged to determine whether it met the discharge standards. The copper content in the metallic copper and the copper content in the copper-containing solid waste were measured by chemical analysis and spectral analysis. According to the formula of copper recovery rate = [(total mass of metallic copper × copper content in metallic copper) / (total mass of copper-containing solid waste × copper content in copper-containing solid waste)] × 100%, the test results are shown in Table 1:

[0090] Table 1

[0091]

[0092]

[0093] As shown in the test results in Table 1, the methods of Examples 1-3 of the present invention can effectively treat copper-containing solid waste, achieving excellent copper recovery rates and low environmental pollution. A comparison of Comparative Example 1 with Examples 1-3 shows that the use of an organic complexing agent can effectively improve copper recovery rates. A comparison of Comparative Example 2 with Examples 1-3 shows that the use of a chitosan composite membrane can reduce the heavy metal content in tail water to meet discharge standards.

[0094] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

[0095] The preferred embodiments of the present invention disclosed above are intended only to help illustrate the present invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the present invention to specific embodiments. Obviously, many modifications and variations are possible based on the contents of this specification. These embodiments are selected and described in detail in this specification to better explain the principles and practical applications of the present invention, thereby enabling those skilled in the art to better understand and utilize the present invention. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A multi-stage treatment method for recycling copper-containing solid waste, characterized in that: The following steps are involved: Step (1): crushing the copper-containing solid waste into small particles, removing large impurities by screening, removing ferromagnetic materials by magnetic separation, and removing light materials by air separation to obtain pretreated copper-containing solid waste; Step (2): adding the pretreated copper-containing solid waste to the leaching agent, stirring, and separating the leaching liquid from the solid phase residue by a filter press; Step (3): adding an organic complexing agent to the leaching solution, stirring, and separating the solid and the liquid to obtain a precipitate and a first waste liquid, washing the precipitate, filtering, and drying to obtain a copper-containing substance, and extracting and refining the copper-containing substance to obtain metallic copper and a second waste liquid; Step (4): mixing the first waste liquid and the second waste liquid to obtain a mixed waste liquid, filtering the mixed waste liquid to obtain dischargeable water; Step (5): adding a stabilizer to the solid phase residue, heating, and stirring to obtain a solidified body.

2. The multi-stage treatment method for resource recovery of copper-containing solid waste according to claim 1, characterized in that: In the step (2), the leaching agent is composed of one or more combinations of sulfuric acid, nitric acid, hydrochloric acid, ammonia water, sodium carbonate, sodium hydroxide and sodium chloride.

3. The multi-stage treatment method for resource recovery of copper-containing solid waste according to claim 1, characterized in that: The preparation method of the organic complexing agent comprises the following steps: Q1: Toluene is added to a container containing carbon tetrachloride, followed by N-bromosuccinimide and benzoyl peroxide, heated to reflux, cooled, filtered, washed, dried, and rotary evaporated to obtain intermediate 1; Q2: Sodium bicarbonate, dichloromethane, distilled water, tetrabutylammonium iodide and intermediate 1 are added to a container, heated to reflux, and N-hydroxypeptide imide is added to the container. After the reflux is completed, the mixture is cooled, separated, the aqueous layer is extracted, the organic phases are combined, washed, dried, and filtered to obtain intermediate 2; Q3: Add intermediate 2 and concentrated hydrochloric acid to a container, heat to reflux, cool to room temperature and filter to obtain a white solid and a filtrate. The filtrate is concentrated under reduced pressure to obtain a white solid. The white solid is washed and distilled to obtain intermediate 3. Q4: Under nitrogen protection, lithium diisopropylamine was added to a round-bottom flask, and 3-methylpyridine was added under low temperature conditions, and stirred to obtain a mixed solution, followed by adding 1-adamantanecarboxylic acid ethyl ester, and continued stirring, washing, and extraction. The organic phase was washed, dried, distilled, and purified to obtain organic matter 1; Q5: Add intermediate 3 to pyridine containing organic matter 1, reflux reaction, add distilled water to the reaction mixture after the reaction is completed, extract, wash the organic phase, dry, distill under reduced pressure, purify, and obtain an organic complexing agent.

4. The multi-stage treatment method for resource recovery of copper-containing solid waste according to claim 3, characterized in that: In the Q1, the molar ratio of toluene, N-bromosuccinimide and benzoyl peroxide is (6-12): (7-14): (0.2-0.4), the heating reflux temperature is 70-80°C, the reflux time is 3-5h, washed with 5wt% sodium bicarbonate solution and ice water, and dried with anhydrous magnesium sulfate; in the Q2, sodium bicarbonate, dichloromethane, distilled water, tetrabutylammonium iodide, intermediate 1 and N-hydroxypeptidyl The dosage ratio of imine is (6-9) g: (30-45) mL: (50-75) mL: (3-4.5) g: (6-9) g: (5-7.5) g, the heating reflux temperature is 55-65° C., the time for adding N-hydroxypeptide imide is 30-45 min, the reflux time is 2-4 h, extraction is performed with dichloromethane, washing is performed with 5wt% sodium bicarbonate solution and distilled water, and drying is performed with anhydrous magnesium sulfate.

5. The multi-stage treatment method for resource recovery of copper-containing solid waste according to claim 3, characterized in that: In the Q3, the usage ratio of the intermediate 2 and concentrated hydrochloric acid is (3-6) g: (20-40) mL, the heating reflux temperature is 70-90° C., the time is 3-5 h, and the white solid is washed with acetonitrile.

6. The multi-stage resource treatment method for copper-containing solid waste according to claim 3, characterized in that: In the Q4, the molar ratio of lithium diisopropylamine, 3-methylpyridine and 1-adamantanecarboxylic acid ethyl ester is (1.7-2.2): (1.8-2.4): (1-1.3), the low temperature is 0-1°C, the stirring time is 1-2h, the stirring time is continued for 3-5h, the mixture is washed with saturated sodium chloride, extracted with ethyl acetate, the organic phase is washed with distilled water 3-5 times, dried with anhydrous sodium sulfate, and purified with a mixed solution of petroleum ether and ethyl acetate in a volume ratio of 5:1 as an eluent; in the Q5, the amount ratio of organic matter 1, intermediate 3 and distilled water is (3-6) mL: (0.65-1.3) g: (10-20) mL, the reflux time is 3-4h, the mixture is extracted with dichloromethane, the organic phase is washed with distilled water, dried with anhydrous sodium sulfate, and purified with a mixed solution of petroleum ether and ethyl acetate in a volume ratio of 7:1 as an eluent.

7. The multi-stage treatment method for resource recovery of copper-containing solid waste according to claim 1, characterized in that: In the step (4), the mixed waste liquid is filtered using a chitosan composite membrane, and the preparation method of the chitosan composite membrane comprises the following steps: S1: chitosan is added to glacial acetic acid to dissolve, then diluted with anhydrous ethanol and placed in an ultrasonic cleaner, and then benzaldehyde is added, heated and shaken to react, to obtain a mixed chitosan solution; S2: adding carbon disulfide and sodium hydroxide solution to the mixed chitosan solution, stirring at room temperature, heating to react, then adding hydrochloric acid to adjust the pH, heating to react, and obtaining modified chitosan; S3: After the glutaraldehyde solution and ethanol are mixed evenly, they are added into a polytetrafluoroethylene reactor, heated for reaction, cooled, and rotary evaporated to obtain a viscous liquid; after the viscous liquid and modified chitosan are mixed and stirred, they are transferred into a mold, quickly frozen under liquid nitrogen, placed in a freeze dryer, and then heated for reaction to obtain a chitosan composite film.

8. The multi-stage resource treatment method for copper-containing solid waste according to claim 7, characterized in that: In S1, the dosage ratio of chitosan, glacial acetic acid, anhydrous ethanol and benzaldehyde is (1-1.5) g: (20-30) mL: (20-30) mL: (0.013-0.019) mL, the volume fraction of glacial acetic acid is 3 vt%, the heating and shaking temperature is 70-80° C., and the time is 4-6 h.

9. The multi-stage treatment method for resource recovery of copper-containing solid waste according to claim 7, characterized in that: In the S2, the mixed chitosan solution, carbon disulfide and sodium hydroxide solution are used in a ratio of (10-15) mL: (2-3) mL: (50-75) mL, the mass fraction of the sodium hydroxide solution is 5 wt%, the stirring time is 30-45 min, the heating reaction temperature is 40-50° C., the time is 3-4 h, the concentration of hydrochloric acid is 1 mol / L, and the pH is adjusted to 9-10.

10. The multi-stage resource treatment method for copper-containing solid waste according to claim 7, characterized in that: In the S3, the volume ratio of glutaraldehyde solution and ethanol is (15-30): (30-60), the volume fraction of glutaraldehyde solution is 5vt%, the heating reaction temperature is 150-160°C, the time is 2-3h, the rotary evaporation temperature is 40-50°C, the time is 4-6h, the amount ratio of viscous liquid and modified chitosan is (10-12)mL: (8-10)g, the mixing and stirring time is 10-15min, placed in a freeze dryer for 10-12h, the heating reaction temperature is 60-70°C, and the reaction time is 4-6h.

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