Extractant and method for separating copper and nickel from waste water

Abstract

The present application provides an extractant and a method for separating copper and nickel from wastewater, which belongs to the field of heavy metal purification in industrial wastewater. The overall molecular structure of this extractant is presented in the form of a "bird". Among them, the "bird body" comes from the Cardo ring of the derivative chemical of bisphenol fluorene, and the three-membered ring is coplanar, which reduces the torsional tension of the entire molecular structure and is conducive to subsequent derivatization; the "two wings" are phenyl ether structures, which are conducive to the free rotation of the benzene rings on both sides of the oxygen atom, and can reduce the steric hindrance of the molecule. The end position of the "two wings" is an acyl hydroxamic acid structural fragment, which is the activated chelating point of the extractant. In addition, although the intramolecular chelation of metal ions is more stable, it is not conducive to subsequent stripping, and the Cardo ring isolates the bisacyl hydroxamic acid structural fragments at both ends of the same molecule, which can prevent the intramolecular chelation of metal ions and provide a guarantee for subsequent metal decomposition and recovery.

Description

Technical Field

[0001] The invention relates to the technical field of heavy metal purification in industrial wastewater, and in particular to an extractant and a method for separating copper and nickel in wastewater. Background Art

[0002] Waste liquid containing copper and nickel in the printed circuit board industry can be traced back to the electroplating and cleaning processes. Electroplating waste liquid containing copper and nickel is on the list of hazardous wastes and poses a potential threat to the environment. Currently, the decomposition-coagulation and precipitation technology is used to treat copper and nickel waste liquids. This method converts the existence of copper and nickel from wastewater to waste solids, but this technology has poor selectivity for the target metal and is easily interfered by impurities, resulting in low purification efficiency. The copper and nickel sludge residues produced are also hazardous wastes.

[0003] The extraction method is widely used in the purification of heavy metal-contaminated water bodies to meet discharge standards due to its simple process operation and strong applicability. It has also become the mainstream process for purifying electroplating wastewater containing copper and nickel. In addition, the copper and nickel extracts after extraction can be recycled by stripping and electrolysis processes, which is conducive to the recycling of resources.

[0004] The core technology of the extraction method is to achieve efficient extraction while taking into account the targeted selective extraction effect. The extractants currently on the market have certain limitations: poor selectivity and difficulty in meeting the requirements of multi-component complex electroplating waste liquid systems. In the extraction and enrichment stage, other types of metal ions are often extracted together, which affects the utilization rate of subsequent stripping-electrolysis resources.

[0005] In view of this, it is necessary to design an extractant and a method for separating copper and nickel in wastewater to solve the above problems. Summary of the invention

[0006] In view of the technical problems existing in the background technology, the present application provides an extractant and a method for separating copper and nickel in wastewater, aiming to solve the technical problems of poor selectivity of target metal ions, low stripping rate and easy contamination of the extractant in the existing extractant.

[0007] In a first aspect, an embodiment of the present application provides an extractant, wherein the extractant is based on a Cardo ring as a skeleton and has diacylhydroxamic acid structural fragments introduced at both ends; the structural formula of the extractant is:

[0008] .

[0009] In this embodiment, the Cardo ring in the extractant isolates the diacylhydroxamic acid structure fragments at both ends of the same molecule, which can prevent the intramolecular chelation of metal ions during the subsequent metal extraction process, thereby providing a guarantee for the subsequent metal decomposition and recovery; and the "two wings" in the structure present a phenyl ether structure, which is conducive to the free rotation of the benzene rings on both sides of the oxygen atom and can reduce the spatial steric hindrance of the molecule; in addition, the phenyl ether structure of the "two wings" in the structure can also regulate the axial π-π bond stacking of the molecular space to the greatest extent, weaken the interaction force between molecules, and improve the solubility performance of the prepared extractant.

[0010] In a second aspect, an embodiment of the present application provides a method for separating copper and nickel in wastewater using an extractant, wherein the extraction is performed using the above-mentioned extractant, and specifically comprises the following steps:

[0011] S1, mixing the extractant with sulfonated kerosene, dissolving by ultrasonication, and obtaining a diluent;

[0012] S2. adjusting the pH value of the wastewater containing copper and nickel to a predetermined value;

[0013] S3. Add the diluent in step S1 to the solution obtained in step S2 to extract copper and nickel in the waste water.

[0014] In the technical solution of the embodiment of the present application, by using the "bird body" and "two wings" to regulate the molecular main chain structure and its steric hindrance, the selective chelation of the target metal (copper, nickel) at the activation site of the acylhydroxamic acid structural fragment can be ensured; in addition, the acylhydroxamic acid structural fragment has the ability to assist antibacterial growth, and iron ions are essential nutrients for the normal metabolic activities of bacteria. The acylhydroxamic acid structural fragment can increase the chelation of iron ions in the water body, limit the growth of bacteria, and effectively inhibit the growth and reproduction of bacteria, thereby achieving efficient selective extraction of copper and nickel and cleaning-antibacterial extraction.

[0015] In some embodiments, in the wastewater containing copper and nickel, copper exists in the form of one or more of sulfate anions, chloride ions, nitrate anions, and citrate anions.

[0016] In some embodiments, in the wastewater containing copper and nickel, nickel exists in the form of one or more of sulfate anions, chloride ions, nitrate anions, and citrate anions.

[0017] In some embodiments, the pH value in step S2 ranges from 1 to 5.

[0018] In this embodiment, by adjusting the pH of industrial (electroplating) wastewater containing copper and nickel within the range of 1 to 5, the existence of the diacylhydroxamic acid structure under alkaline conditions is avoided, and the hydroxamic acid group undergoes a hydrolysis reaction to form alcohol and carboxylate, thereby causing the molecular structure to be destroyed, thereby ensuring that the extractant can efficiently extract copper and nickel.

[0019] In some embodiments, in the diluent, the mass ratio of the extractant to sulfonated kerosene is 1:10-100.

[0020] In some embodiments, the wastewater containing copper and nickel includes one or more of catalyst waste liquid, metallurgical waste liquid, electronic waste leaching solution, photovoltaic module etching liquid, and waste circuit board electroplating liquid.

[0021] In some embodiments, the extraction efficiency of the extractant for copper and nickel in wastewater is above 95%.

[0022] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solution of the present application, the following is a brief introduction to the drawings used in the present application. Obviously, the drawings described below are only some embodiments of the present application, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0024] Figure 1 The synthetic route of the extractant in the examples of this application;

[0025] Figure 2 The NMR of the extractant in the present application example is 1 H-NMR spectrum;

[0026] Figure 3 The chemical molecular structure diagram of the extractant in the embodiment of the present application;

[0027] Figure 4 This is a schematic diagram of the structure of the extractant in the embodiment of the present application;

[0028] Figure 5 Actual images of the extractant (left) and extractant diluent (right) provided for this application. DETAILED DESCRIPTION

[0029] The following embodiments of the technical solution of the present application are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0031] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0032] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0033] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0034] In the prior art, most extractants used in the field of wastewater treatment containing copper and nickel use organophosphorus extractants, which can form stable complexes with copper and nickel ions to achieve the extraction of metal ions; however, organophosphorus extractants have certain toxicity and will have long-term effects on aquatic organisms: and the complexes formed by metal ions and extractants are very stable, making it difficult to extract metal ions from the organic phase, affecting the metal recovery efficiency. In the prior art, there are also extractants with the structure of diacylhydroxamic acid, but there are still difficulties in subsequent back extraction due to the fact that the chelates formed by metal ions and extractants are very stable. Therefore, it is particularly important to prepare an extractant that can both efficiently and selectively extract copper and nickel and ensure the high efficiency of back extraction of metal ions.

[0035] In order to solve the above-mentioned technical problems, the present application provides an extractant and a method for separating copper and nickel from wastewater, wherein the Cardo ring of the derivative chemical of bisphenol fluorene presents a coplanar three-membered ring, thereby reducing the torsional tension of the entire molecular structure; the phenyl ether structure located on both sides of the molecule allows the benzene rings on both sides of the oxygen atom to rotate freely; the extreme ends of the "two wings" are acylhydroxamic acid structure fragments, which are the activated chelating points of the extractant, while ensuring that the probability of contact between the molecule and the metal ion is increased and the extraction efficiency is improved, while preventing the metal ion from being chelated intramolecularly during the subsequent metal extraction process, thereby ensuring the subsequent metal complex breaking and recovery.

[0036] Please refer to Figure 1 In the first aspect, the present invention provides an extractant, wherein the extractant is based on a Cardo ring as a skeleton and has diacylhydroxamic acid structural fragments introduced at both ends; the general structural formula of the extractant is:

[0037] .

[0038] The prepared extractant has a molecular structure that is "bird-like". The "bird body" is derived from the Cardo ring of the derivative chemical of bisphenol fluorene, and the three-membered ring formed is coplanar, which reduces the torsional tension of the entire molecular structure and is conducive to subsequent derivatization; the "two wings" present a phenyl ether structure, which is conducive to the free rotation of the benzene rings on both sides of the oxygen atom and can reduce the steric hindrance of the molecule; the end of the "two wings" is the acyl hydroxamic acid structure fragment, which is the activation chelation point of the extractant. In addition, because the intramolecular chelation stability of metal ions is stronger, it is not conducive to subsequent back extraction (decomplexation reaction), and the Cardo ring separates the bisacyl hydroxamic acid structure fragments at both ends of the same molecule, which can prevent the intramolecular chelation of metal ions and provide a guarantee for subsequent metal decomplexation recovery. The phenyl ether structure of the "two wings" can regulate the axial π-π bond stacking of the molecular space to the greatest extent. Through the regulation of the molecular main chain structure and its steric hindrance by the "bird body" and the "two wings", the activation site of the acyl hydroxamic acid structure fragment can be guaranteed to selectively chelate the target metal (copper, nickel).

[0039] In addition, the acylhydroxamic acid structural fragments have the ability to assist in the growth of antibacterial agents. Iron ions are essential nutrients for the normal metabolic activities of bacteria. The acylhydroxamic acid structural fragments can increase the chelated iron ions in the water, limit the growth of bacteria, and effectively inhibit the growth and reproduction of bacteria, thereby achieving efficient selective extraction of copper and nickel and cleaning-antibacterial extraction.

[0040] Furthermore, in some embodiments, the method for preparing the extractant specifically comprises the following steps:

[0041] S1. Put 0.5 mol of bisphenol fluorene into a 3L three-necked round-bottom flask, and dissolve the bisphenol fluorene in a mixed solution of 1L of DMF and 1L of toluene; after it is dissolved, put 1 mol of anhydrous potassium carbonate into the above suspension, heat it under reflux, and remove the generated water and toluene by azeotropic distillation; when no more water is generated, remove the excess toluene by distillation; after the above reaction is completed, reduce the system temperature to 50-60°C, add 1-1.2 mol of p-fluorobenzonitrile (B), and then raise the system temperature to 150-180°C and react for 6-8h; after the reaction is completed, put the suspension into water while it is hot to produce a large amount of white powdery crude product, which is first filtered and extracted for purification, then repeatedly washed with water and methanol solution, and vacuum dried to obtain compound C, wherein the yield is 90-92%;

[0042] S2. Transfer 0.2-0.5 mol of compound C to a 5L three-necked flask and dissolve it in anhydrous tetrahydrofuran solution under nitrogen protection. At this time, the molar concentration of compound C is 2-5 mol / L.

[0043] 1-3 mol of lithium aluminum hydride was added to anhydrous tetrahydrofuran under nitrogen protection, stirred for 30 min, and transferred to a constant pressure titration funnel to obtain a lithium aluminum hydride suspension;

[0044] The three-necked flask containing the mixed solution of compound C and anhydrous tetrahydrofuran solution prepared above is placed in an ice-water bath, and under the protection of nitrogen atmosphere, the prepared lithium aluminum hydride suspension is added dropwise using a constant pressure titration funnel, and the reaction is carried out for 24 to 48 hours; after the reaction is completed, it is filtered; then the liquid is collected, and the solvent in the liquid is removed by vacuum rotary evaporation, and the residue is dissolved in a chloroform solution, and the chloroform solvent is removed by vacuum rotary evaporation again, and finally an oily colorless oil D is collected, wherein the yield is 78 to 81%;

[0045] S3. Pour 0.1-0.2 mol of the oily substance D into a 3L three-necked flask, and add 1L of ethanol solution and 1 mol of sodium ethoxide in sequence, and stir for 0.5-1h; then add 0.15-0.3 mol of N-hydroxybenzenesulfonamide, and react for 6-8h in an ice-water bath; after the reaction, return the temperature to room temperature; then, remove the solvent methanol under rotary evaporation vacuum conditions, and dissolve the residue in 500ml of ether; after complete dissolution, extract with 2mol / L NaOH, and collect the aqueous phase; then, acidify the aqueous phase with hydrochloric acid, extract with ethyl acetate, and after the extraction, remove the ethyl acetate by rotary evaporation vacuum, and finally collect the residual oily substance, i.e., the target extractant, with a yield of 57-63%.

[0046] Please refer to Figure 2In a second aspect, the present application provides a method for separating copper and nickel from wastewater using an extractant, wherein the extraction is performed using the extractant, and specifically comprises the following steps:

[0047] S1, mixing the extractant with sulfonated kerosene, dissolving by ultrasonication, and obtaining a diluent;

[0048] S2. adjusting the pH value of the wastewater containing copper and nickel to a predetermined value;

[0049] S3. Add the diluent in step S1 to the solution obtained in step S2 to extract copper and nickel in the waste water.

[0050] Among them, the use of an extractant that regulates the molecular main chain structure and its steric hindrance by forming a "bird body" and "two wings" structure pattern can ensure that the activation site of the hydroxamic acid structural fragment selectively chelates the target metal (copper, nickel). In addition, the hydroxamic acid structural fragment has antibacterial growth ability, which can effectively inhibit bacterial growth and reproduction during the extraction process, ensuring the cleanliness of the environment.

[0051] Furthermore, in some embodiments, in the wastewater containing copper and nickel, copper exists in the form of one or more of sulfate anions, chloride ions, nitrate anions, and citrate anions.

[0052] Furthermore, in some embodiments, in the wastewater containing copper and nickel, nickel exists in the form of one or more of sulfate anions, chloride ions, nitrate anions, and citrate anions.

[0053] Furthermore, in some embodiments, the pH value in step S2 ranges from 1 to 5.

[0054] By adjusting the pH of industrial wastewater containing copper and nickel to a range of 1 to 5, the existence of the diacylhydroxamic acid structure under alkaline conditions is avoided, and the hydroxamic acid group undergoes a hydrolysis reaction to form alcohol and acid, thereby causing the activation site N + Therefore, the efficient extraction of copper and nickel by the extractant can be ensured.

[0055] Furthermore, in some embodiments, in the diluent, the mass ratio of the extractant to sulfonated kerosene is 1:10-100.

[0056] Furthermore, in some embodiments, the wastewater containing copper and nickel includes one or more of catalyst waste liquid, metallurgical waste liquid, electronic waste leaching solution, photovoltaic module etching liquid, and waste circuit board electroplating liquid.

[0057] Furthermore, in some embodiments, the extraction efficiency of the extractant for copper and nickel in wastewater is above 95%.

[0058] In the technical solution of the embodiment of the present application, the Cardo ring of the derivative chemical of bisphenol fluorene presents a coplanar three-membered ring, which reduces the torsional tension of the entire molecular structure; the phenyl ether structure located on both sides of the molecule allows the benzene rings on both sides of the oxygen atom to rotate freely; the end positions of the "two wings" are acylhydroxamic acid structure fragments, which are the activated chelating points of the extractant. While ensuring that the probability of contact between the molecule and the metal ion is increased and the extraction efficiency is improved, it prevents the metal ion from being chelated intramolecularly during the subsequent metal extraction process, thereby ensuring the subsequent metal complex breaking and recovery, thereby improving the efficiency of extraction and back-extraction.

[0059] Some specific embodiments are listed below. It should be noted that the embodiments described below are exemplary and are only used to explain the present application, and should not be construed as limiting the present application. If specific techniques or conditions are not specified in the embodiments, the techniques or conditions described in the literature in this area or the product specifications are used. The reagents or instruments used without specifying the manufacturer are all conventional products that can be obtained commercially.

[0060] Example 1

[0061] Preparation of efficient, clean and antibacterial extractants:

[0062] like Figure 1 As shown, the preparation method of the extractant comprises the following steps:

[0063] S1. Put 0.5 mol of bisphenol fluorene into a 3L three-necked round-bottom flask, and dissolve bisphenol fluorene in a mixed solution of 1L of DMF and 1L of toluene; after it is dissolved, put 1 mol of anhydrous potassium carbonate into the above suspension, heat and reflux, and remove the generated water and toluene by azeotropic distillation; when no more water is generated, remove the excess toluene by distillation; after the above reaction is completed, reduce the system temperature to 50°C, and add 1 mol of p-fluorobenzonitrile (B); then raise the system temperature to 150°C and react for 6h. After the reaction is completed, put the suspension into water while hot to produce a large amount of white powdery crude product, which is first filtered and extracted for purification, then repeatedly washed with water and methanol solution, and vacuum dried to obtain compound C with a yield of 90%.

[0064] S2, 0.2mol of compound C is transferred to a 5L three-necked flask, dissolved in anhydrous tetrahydrofuran solution under nitrogen protection, and now compound C molar concentration is 2mol / L. 1mol of lithium aluminum hydride is added to anhydrous tetrahydrofuran under nitrogen protection, stirred for 30min, and transferred to a constant pressure titration funnel. The three-necked flask is placed in an ice-water bath, and under nitrogen atmosphere protection, a constant pressure titration funnel is used to dropwise add lithium aluminum hydride suspension, and the reaction is 24h. The reaction terminates, and the liquid is filtered, and the solvent is evaporated in vacuum, and the residue is dissolved in a chloroform solution, and the chloroform solvent is removed by vacuum evaporation again. Oily colorless oil D is collected, and the yield is 78%.

[0065] S3. Add 0.1 mol of oily substance D to a 3L three-necked flask, add 1L of ethanol solution, then add 1 mol of sodium ethoxide and stir for 0.5h. Add 0.15 mol of N-hydroxybenzenesulfonamide to the three-necked flask and react for 6h in an ice-water bath. After the reaction is over, return to room temperature. Remove the solvent methanol under vacuum conditions, and dissolve the residue in 500ml of ether until it is completely dissolved. Extract with 2mol / L NaOH and collect the aqueous phase. Acidify the aqueous phase with hydrochloric acid and finally extract with ethyl acetate. After the extraction is completed, remove the ethyl acetate under vacuum conditions and collect the residual oily substance E.

[0066] S4. After the reaction, the dimethyl sulfoxide solution and excess malonic acid were removed by rotary distillation under reduced pressure, and the brown oil was collected. Deionized water was added, ultrasonically dissolved, and filtered to remove inorganic impurities. Subsequently, tetrahydrofuran and deionized water were added in a volume ratio of 1:1, extracted, and the organic phase was collected, dried over anhydrous magnesium sulfate, filtered, and the liquid phase was collected. The solvent was removed by rotary distillation to obtain a yellow product with a yield of 57%, of which the NMR of the extractant was 1:1. 1 H-NMR spectrum Figure 2 As shown, the corresponding chemical molecular structure and the specific analysis diagram of the structure are as follows Figure 3 and Figure 4 shown.

[0067] The physical form of the extractant is Figure 5 As shown:

[0068] The extractant prepared by the above method has a Cardo ring as a skeleton, and introduces diacylhydroxamic acid structural fragments at both ends; the structural formula of the extractant is:

[0069] .

[0070] Application of extraction agent:

[0071] The method for separating copper and nickel from wastewater by using an extractant specifically comprises the following steps:

[0072] S1, mixing the extractant with sulfonated kerosene, dissolving by ultrasonication, and obtaining a diluent;

[0073] The diluent (such as Figure 4 As shown), the mass ratio of the extractant to the sulfonated kerosene is 1:50;

[0074] S2. Adjust the pH value of the wastewater containing copper and nickel to 1 with hydrochloric acid;

[0075] In the wastewater containing copper and nickel, copper exists in the form of sulfate anions, chloride ions, nitrate anions, and citrate anions; nickel exists in the form of sulfate anions, chloride ions, nitrate anions, and citrate anions;

[0076] The wastewater containing copper and nickel is waste circuit board electroplating liquid;

[0077] S3. At room temperature, add 100 ml of the diluent in step S1 to the 50 ml solution obtained in step S2, and shake in a water bath oscillator for 5 min, then take the organic phase, and use ICP-OES to detect the concentrations of copper and nickel in the inorganic liquid phase solution, and finally calculate the extraction rate of the extractant.

[0078] Embodiment 2~5

[0079] Embodiments 2 to 5 respectively provide an application of an extractant, which differs from Embodiment 1 in that step S2 adjusts the pH value of the wastewater solution containing copper and nickel differently. The pH values ​​of Embodiments 2 to 5 are 2, 3, 4, and 5, respectively. The remaining steps are consistent with Embodiment 1 and are not described again.

[0080] Comparative Example 1~2

[0081] Comparative Examples 1 and 2 respectively provide an application of an extractant, which differs from Example 1 in that step S2 adjusts the pH value of the wastewater solution containing copper and nickel differently. The pH value of Comparative Example 1 is 6; the pH value of Comparative Example 2 is 8. The remaining steps are consistent with Example 1 and are not described again.

[0082] The effects of pH on the adsorption of copper and nickel by the extractants used in Examples 1 to 5 and Comparative Examples 1 to 2 are shown in Table 1.

[0083] Table 1 Extraction capacity of copper and nickel by extractants at different pH values

[0084]

[0085] Note: “—” indicates that the value is below the detection limit of ICP-OES.

[0086] It can be seen from Table 1 that when the pH of industrial wastewater containing copper and nickel is adjusted in the range of 1 to 5, the extractants can efficiently extract copper and nickel, and the extraction effect is more than 95%; when the pH of industrial wastewater containing copper and nickel is ≥6, the extraction ability of the extractant is negatively affected. The main reason is that when the pH is 6, part of the nickel ions precipitate and leave the water phase. The process of extracting metal ions by the extractant belongs to the liquid interface phase transfer reaction, so the deposited nickel compounds cannot be extracted.

[0087] The high-efficiency, clean, and antibacterial extractant prepared in Example 1 was used to extract and separate copper and nickel from various coexisting ion solutions. The specific operation steps are as follows:

[0088] A series of mixed solutions containing copper, nickel, manganese, tin and molybdenum in different concentration ratios were prepared. 100 ml of the dilution of the extractant (the mass ratio of the extractant to sulfonated kerosene was 1:50) was added to 500 ml of the mixed solution, and after shaking for 5 minutes, the inorganic liquid phase was taken and the concentration of each metal ion in the solution was detected by ICP-OES to calculate the extraction rate.

[0089] The extraction effects of the extractants on the metal ions in the blend solution are shown in Table 2.

[0090] Table 2 Extraction ability of the extractant for each metal ion in the blend solution

[0091]

[0092] Note: “—” indicates that the value is below the detection limit of ICP-OES.

[0093] As can be seen from Table 2, the extractant has excellent extraction selectivity for copper and nickel, and basically does not extract the other coexisting metal ions manganese, tin and molybdenum. The main reason is attributed to the unique molecular structure and spatial structure of the prepared efficient, clean and antibacterial extractant, that is, the "bird body", "bird wings" and "functionalized functional group fragments at the tail end of the bird wings" work together to achieve the effect of efficient selective chelating extraction of copper and nickel ions.

[0094] Embodiment 6-10

[0095] Examples 6 to 10 respectively provide an application of an extractant, which differs from Example 1 in that different acids are used in step S2. The acids used in Examples 6 to 10 are shown in Table 3. The remaining steps are consistent with Example 1 and are not described here.

[0096] Embodiment 11

[0097] Example 11 provides an application of an extractant, which is different from Example 6 in that the pH value of the wastewater solution containing copper and nickel is adjusted differently in step S2, and the pH value of Example 11 is 5. The remaining steps are consistent with Example 1 and are not described again.

[0098] Example 12

[0099] Example 12 provides an application of an extractant, which is different from Example 7 in that the pH value of the wastewater solution containing copper and nickel is adjusted differently in step S2, and the pH value of Example 12 is 5. The remaining steps are consistent with Example 1 and are not described again.

[0100] Example 13

[0101] Example 13 provides an application of an extractant, which is different from Example 8 in that the pH value of the wastewater solution containing copper and nickel is adjusted differently in step S2, and the pH value of Example 11 is 5. The remaining steps are consistent with Example 1 and are not described again.

[0102] Embodiment 14

[0103] Example 14 provides an application of an extractant, which is different from Example 9 in that the pH value of the wastewater solution containing copper and nickel is adjusted differently in step S2, and the pH value of Example 14 is 5. The remaining steps are consistent with Example 1 and are not described again.

[0104] Embodiment 15

[0105] Example 15 provides an application of an extractant, which is different from Example 10 in that the pH value of the wastewater solution containing copper and nickel is adjusted differently in step S2, and the pH value of Example 15 is 5. The remaining steps are consistent with Example 1 and are not described again.

[0106] The acids and corresponding pH values ​​used in Examples 11 to 15, and the corresponding extraction effects of copper and nickel are shown in Table 3.

[0107] Table 3 Extraction effect of extractants on copper and nickel at different pH values

[0108]

[0109] As shown in Table 3, the prepared extractant maintains a high extraction capacity for copper and nickel in a complex solution system of various anion species, and the extraction effect is more than 95% in the pH range (1-5).

[0110] In summary, the extractant provided by the present invention and the method for separating copper and nickel in wastewater, the prepared extractant, the overall molecular structure of which is presented in the form of a "bird". Among them, the "bird body" is derived from the Cardo ring of the derivative chemical of bisphenol fluorene, and the three-membered ring formed is coplanar, which reduces the distortion tension of the entire molecular structure and is conducive to subsequent derivatization; the "two wings" are phenyl ether structures, which are conducive to the free rotation of the benzene rings on both sides of the oxygen atom, can reduce the steric hindrance of the molecule, and the phenyl ether structure can adjust the axial π-π bond stacking of the molecular space to the greatest extent, weaken the interaction force between molecules, and improve the solubility of the prepared extractant; in addition, the end position of the "two wings" is the acyl hydroxamic acid structure fragment, which becomes the activation chelating point of the extractant.

[0111] In addition, although the intramolecular chelation of metal ions is more stable, it is not conducive to subsequent stripping. The Cardo ring isolates the diacylhydroxamic acid structural fragments at both ends of the same molecule, which can prevent the intramolecular chelation of metal ions and provide a guarantee for the subsequent metal decomposition and recovery.

[0112] This regulation of the molecular main chain structure and its steric hindrance by forming a "bird body" and "two wings" structure can ensure that the activation site of the hydroxamic acid structural fragment selectively chelates the target metal (copper and nickel). In addition, the hydroxamic acid structural fragment has antibacterial ability and can effectively inhibit bacterial growth and reproduction. The above series of synergistic effects have achieved a qualitative change in the chelation effect of copper and nickel ions, thereby achieving efficient and selective extraction of copper and nickel.

[0113] It should be noted that the present application is not limited to the above-mentioned embodiments. The above-mentioned embodiments are only examples, and the embodiments having the same structure as the technical idea and exerting the same effect within the scope of the technical solution of the present application are all included in the technical scope of the present application. In addition, without departing from the scope of the main purpose of the present application, various modifications that can be thought of by those skilled in the art to the embodiments and other methods of combining some of the constituent elements in the embodiments are also included in the scope of the present application.

Claims

1. An extractant, wherein the extractant is based on a Cardo ring as a skeleton and has diacylhydroxamic acid structural fragments introduced at both ends; the structural formula of the extractant is: 。 2. A method for separating copper and nickel from wastewater using an extractant, characterized in that: The extraction is carried out using the extractant according to claim 1, which specifically comprises the following steps: S1, mixing the extractant with sulfonated kerosene, dissolving by ultrasonication, and obtaining a diluent; S2. Adjusting the pH value of the wastewater containing copper and nickel to a predetermined value; the pH value ranges from 1 to 5; S3. Add the diluent in step S1 to the solution obtained in step S2 to extract copper and nickel in the waste water.

3. The method for separating copper and nickel from waste water by an extractant according to claim 2, characterized in that: In the wastewater containing copper and nickel, copper exists in the form of one or more of sulfate anions, chloride ions, nitrate anions and citrate anions.

4. The method for separating copper and nickel from waste water by an extractant according to claim 2, characterized in that: In the wastewater containing copper and nickel, nickel exists in the form of one or more of sulfate anions, chloride ions, nitrate anions and citrate anions.

5. The method for separating copper and nickel from waste water by an extractant according to claim 2, characterized in that: In the diluent, the mass ratio of the extractant to the sulfonated kerosene is 1:10-100.

6. The method for separating copper and nickel from waste water by an extractant according to claim 2, characterized in that: The wastewater containing copper and nickel includes one or more of catalyst waste liquid, metallurgical waste liquid, electronic waste leaching solution, photovoltaic module etching liquid, and waste circuit board electroplating liquid.

7. The method for separating copper and nickel from waste water by an extractant according to claim 2, characterized in that: The extraction effect of the extractant on copper and nickel in wastewater is more than 95%.

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