Method for deeply separating similar metal elements based on Lewis acidity regulation

Abstract

The invention relates to the technical field of separation engineering, in particular to a method for deeply separating similar metal elements based on Lewis acidity regulation, which comprises the following steps: adding one or more organic matter molecules into a to-be-separated metal ion system to form a complex with metal ions so as to change the original Lewis acidity of the metal ions; compared with metal ions in an original system, the Lewis acidity of complexes formed by the added organic matter molecules and the metal ions is obviously different, and deep separation of similar or similar metal elements can be achieved in an adsorption mode by means of the difference; in this way, the technical problems that in the prior art, when an extraction method is adopted for achieving separation of metal ions, a large amount of organic solvent needs to be used, operation is tedious, and an extracting agent is aged and prone to emulsification are solved.

Description

Technical Field

[0001] The invention relates to the technical field of separation engineering, and in particular to a method for deep separation of similar metal elements based on Lewis acid regulation. Background Art

[0002] In the fields of metal processing, mineral extraction and environmental management, it is often necessary to separate and purify mixtures containing multiple metal elements. In particular, when these metal elements have similar properties, traditional physical or chemical separation methods often fail to achieve the desired separation effect. Extraction, as a common method for separating metal ions, mainly relies on the selective binding between the extractant and the target metal ions, and separates the metal ions from the mixture by solvent extraction.

[0003] However, the extraction method requires a large amount of organic solvent to separate metal ions, and there are problems such as cumbersome operation, aging of the extractant and easy emulsification. Summary of the invention

[0004] The purpose of the present invention is to provide a method for deep separation of similar metal elements based on Lewis acid regulation, aiming to solve the technical problems of using a large amount of organic solvent when using the extraction method to separate metal ions in the prior art, and the existence of cumbersome operation, aging of the extractant and easy emulsification.

[0005] To achieve the above object, the present invention adopts a method for deep separation of similar metal elements based on Lewis acid regulation, comprising the following steps: Step 1: First, add one or more organic molecules to the metal ion system to be separated to form a complex; Step 2: Adsorption of one or several metal ion complexes is achieved by selective adsorption, and at least one metal ion complex is not adsorbed, thereby achieving separation; Step 3: Desorb the adsorbed metal ion complex under strong acid or strong base conditions to release the corresponding metal ions, thereby achieving deep separation between metal ions with similar or close properties.

[0006] Among them, the organic molecules added to the metal ion system to be separated are small organic molecules, and the small organic molecules include amino acids, tartaric acid, citric acid, ethylenediaminetetraacetic acid, imidazole, imidazolidinyl urea, imidazole aldehyde, 2-imidazolidinone, 1,2-dimethylimidazole, imidazole aldehyde, guanyl thiourea, thiourea, ethylene thiourea, and allyl thiourea.

[0007] The molar ratio of the amount of organic molecules added to the amount of metal ions in the metal ion system to be separated is 0.1-5.

[0008] After the organic molecules are added into the metal ion system, they are kept at 5°C-55°C for 0-60 minutes.

[0009] After the organic molecules are added to the metal ion system, stirring is performed while the system is maintained, and the stirring time is 0-60 minutes and the rotation speed is 0-300 rpm.

[0010] The stirring method may be continuous stirring or intermittent stirring.

[0011] Selective adsorption refers to the adsorption amount of a certain target substance being 5 times greater than that of the interference substance.

[0012] Wherein, in step 3, when desorption is carried out under strong acid or strong base conditions, strong acid refers to a pH value less than 2, and strong base refers to a pH value greater than 12.

[0013] The present invention discloses a method for deep separation of similar metal elements based on Lewis acidity regulation, wherein one or more organic molecules are added to the metal ion system to be separated so as to form a complex with the metal ions to change the original Lewis acidity of the metal ions. Compared with the metal ions in the original system, there is a significant difference in the Lewis acidity between the complexes formed by the added organic molecules and metal ions, and this difference can be used to achieve deep separation of similar or close metal elements by adsorption. The present invention introduces organic molecules to form complexes with metal ions, so that there is a significant difference in the Lewis acidity between the metal ions to be separated, and this difference is used to achieve the purpose of deep separation between metal ions, thereby solving the technical problems of the prior art that a large amount of organic solvents are needed to achieve separation between metal ions by extraction, and there are cumbersome operations, aging of the extractant, and easy emulsification. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. 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 creative work.

[0015] Figure 1 It is a flow chart of the steps of the method for deep separation of similar metal elements based on Lewis acid regulation of the present invention. DETAILED DESCRIPTION

[0016] Embodiments of the present invention are described in detail below. Examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, but should not be construed as limiting the present invention.

[0017] See also Figure 1 , Figure 1 It is a flow chart of the steps of the method for deep separation of similar metal elements based on Lewis acid regulation of the present invention.

[0018] The present invention provides a method for deep separation of similar metal elements based on Lewis acid regulation, comprising the following steps: S101, firstly, adding one or more organic molecules to the metal ion system to be separated to form a complex; According to this specific embodiment, the organic molecules added to the metal ion system to be separated are small organic molecules, and the small organic molecules include amino acids, tartaric acid, citric acid, ethylenediaminetetraacetic acid, imidazole, imidazolidinyl urea, imidazole aldehyde, 2-imidazolidinone, 1,2-dimethylimidazole, imidazole aldehyde, guanyl thiourea, thiourea, ethylene thiourea, and allyl thiourea; The molar ratio of the amount of organic molecules added to the amount of metal ions in the metal ion system to be separated is 0.1-5; After the organic molecules are added to the metal ion system, they are kept at 5°C-55°C for 0-60 minutes; After the organic molecules are added to the metal ion system, stirring is performed while maintaining the system. The stirring time is 0-60 minutes and the rotation speed is 0-300 rpm. The stirring method can be continuous stirring or intermittent stirring.

[0019] S102, achieving adsorption of one or several metal ion complexes by selective adsorption, wherein at least one metal ion complex is not adsorbed, thereby achieving separation; With respect to this specific embodiment, selective adsorption means that the amount of adsorption of a certain target substance is much greater than 5 times the amount of adsorption of the interferent.

[0020] S103. The adsorbed metal ion complex is desorbed under strong acid or strong base conditions to release the corresponding metal ions, thereby achieving deep separation between metal ions with similar or close properties.

[0021] According to this specific embodiment, when desorption is carried out under strong acid or strong base conditions, strong acid refers to a pH value less than 2, and strong base refers to a pH value greater than 12.

[0022] A method for deep separation of similar metal elements based on Lewis acidity regulation of the present embodiment is used, and one or more organic molecules are added to the metal ion system to be separated, so that they form complexes with metal ions to change the original Lewis acidity of the metal ions. Compared with the metal ions in the original system, there is a significant difference in the Lewis acidity between the complexes formed by the added organic molecules and metal ions, and this difference can be used to achieve deep separation of similar or similar metal elements by adsorption. The present invention introduces organic molecules to form complexes with metal ions, so that there is a significant difference in the Lewis acidity between the metal ions to be separated, and this difference is used to achieve the purpose of deep separation between metal ions, which solves the problem that a large amount of organic solvents are needed to separate metal ions by extraction in the prior art, and there are technical problems such as cumbersome operation, aging of the extractant and easy emulsification. Example

[0023] The present technical solution is used to separate indium ions (In 3+ ) and iron ions (Fe 3+ ) when the indium ion (In 3+ ) and iron ions (Fe 3 + ) as two metal ions with similar properties. In a 1L solution containing indium ions (0.2 mmol / L) and iron ions (5.8 mmol / L), 7.2mmol / L of citric acid was added, and then fully stirred for 30 minutes at room temperature. It was passed through an adsorption column filled with nanofibers. It was found that the concentration of indium ions in the effluent was 0.008 mmol / L, while the concentration of iron ions was 5.794 mmol / L. This shows that the Lewis acidity of indium and iron ions can be regulated by citric acid, and their electron-accepting ability is significantly changed, thereby achieving a deep separation between indium ions and iron ions. Example

[0024] When the technical solution is used to separate cobalt ions and nickel ions, cobalt ions and nickel ions are treated as two similar metal ions. In a 2L solution containing cobalt ions (0.2mmol / L) and nickel ions (0.3mmol / L), 0.6mmol / L of tartaric acid is added, and the mixture is stirred for 30 minutes at room temperature. The mixture is then passed through an adsorption column filled with nanofibers. It is found that the concentration of cobalt ions in the effluent is 0.199mmol / L, while the concentration of nickel ions is only 0.003mmol / L. This indicates that the Lewis acidity of nickel and cobalt ions can be regulated by tartaric acid, and their deep separation can be achieved by adsorption.

[0025] The nanofiber material used for filling the adsorption column in Example 1 and Example 2 can be prepared by using the preparation method of nanofiber adsorption material for deep removal of nickel complexes in water disclosed in the prior art patent application number 202411115498.6.

[0026] What is disclosed above is only a preferred embodiment of the present invention, and it certainly cannot be used to limit the scope of rights of the present invention. Ordinary technicians in this field can understand that all or part of the processes of the above embodiment and equivalent changes made according to the claims of the present invention still fall within the scope of the invention.

Claims

1. A method for deep separation of similar metal elements based on Lewis acid regulation, characterized in that: The steps include: Step 1: First, add one or more organic molecules to the metal ion system to be separated to form a complex; Step 2: Adsorption of one or several metal ion complexes is achieved by selective adsorption, and at least one metal ion complex is not adsorbed, thereby achieving separation; Step 3: Desorb the adsorbed metal ion complex under strong acid or strong base conditions to release the corresponding metal ions, thereby achieving deep separation between metal ions with similar or close properties.

2. The method for deep separation of similar metal elements based on Lewis acidity regulation according to claim 1, characterized in that: The organic molecules added to the metal ion system to be separated are small organic molecules, including amino acids, tartaric acid, citric acid, ethylenediaminetetraacetic acid, imidazole, imidazolidinyl urea, imidazole aldehyde, 2-imidazolidinone, 1,2-dimethylimidazole, imidazole aldehyde, guanyl thiourea, thiourea, ethylene thiourea, and allyl thiourea.

3. The method for deep separation of similar metal elements based on Lewis acidity regulation according to claim 2, characterized in that: The molar ratio of the amount of organic molecules added to the amount of metal ions in the metal ion system to be separated is 0.1-5.

4. The method for deep separation of similar metal elements based on Lewis acidity regulation according to claim 3, characterized in that: After the organic molecules are added to the metal ion system, they are kept at 5°C-55°C for 0-60 minutes.

5. The method for deep separation of similar metal elements based on Lewis acidity regulation according to claim 4, characterized in that: After the organic molecules are added to the metal ion system, stirring is performed while maintaining the system. The stirring time is 0-60 minutes and the rotation speed is 0-300 rpm.

6. The method for deep separation of similar metal elements based on Lewis acidity regulation according to claim 5, characterized in that: The stirring method can be continuous stirring or intermittent stirring.

7. The method for deep separation of similar metal elements based on Lewis acidity regulation according to claim 6, characterized in that: Selective adsorption means that the amount of adsorption of a certain target substance is 5 times greater than that of the interference substance.

8. The method for deep separation of similar metal elements based on Lewis acidity regulation according to claim 7, characterized in that: In step 3, when desorption is carried out under strong acid or strong base conditions, strong acid refers to a pH value of less than 2, and strong base refers to a pH value of greater than 12.

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