阅读说明：本技术 一种分离提纯粗碲化亚铜渣的方法 (Method for separating and purifying crude cuprous telluride slag ) 是由 潘锦功 傅干华 段杰明 周毅 郑林 彭寿 马立云 于 2020-05-08 设计创作，主要内容包括：本发明公开了一种分离提纯粗碲化亚铜渣的方法,它是先将粗碲化亚铜渣进行氧化酸浸除去粗碲化亚铜渣中的银、硒等杂质,得到含有铜、碲的浸出液；再通过调节浸出液的pH值和铜含量后,用羟胯萃取剂对其进行萃取和反萃操作,实现铜、碲的分离。本发明方法不通过反复酸浸中和除杂等传统工艺,直接通过萃取剂的选择来实现碲、铜的分离,减少了设备的投入、缩短了工艺路线。通过本发明方法可以解决现有常规通过酸浸、中和、碱溶、再中和、除杂、酸浸等工序分离粗碲化亚铜渣带来的高成本多设备的问题,并且本发明方法可以减少在分离过程中出现的环境污染、分离不彻底等问题。(The invention discloses a method for separating and purifying crude cuprous telluride residues, which comprises the steps of firstly carrying out oxidation acid leaching on the crude cuprous telluride residues to remove impurities such as silver, selenium and the like in the crude cuprous telluride residues, and obtaining a leaching solution containing copper and tellurium; and then, after the pH value and the copper content of the leachate are adjusted, a hydroxyl-ketone extractant is used for extracting and back-extracting the leachate, so that the separation of copper and tellurium is realized. The method provided by the invention does not adopt traditional processes such as repeated acid leaching, neutralization and impurity removal, and the like, and directly adopts the selection of an extracting agent to realize the separation of tellurium and copper, so that the investment of equipment is reduced, and the process route is shortened. The method can solve the problems of high cost and multiple devices caused by separating the crude cuprous telluride slag through the conventional processes of acid leaching, neutralization, alkali dissolution, secondary neutralization, impurity removal, acid leaching and the like, and can reduce the problems of environmental pollution, incomplete separation and the like in the separation process.)

1. A method for separating and purifying crude cuprous telluride slag is characterized by comprising the following steps: the method comprises the following steps:

(1) pulping the crude cuprous telluride residues, adding the pulped crude cuprous telluride residues into acid liquor containing an oxidant, and performing oxidation acid leaching to remove impurities such as silver, selenium and the like in the crude cuprous telluride residues to obtain leachate containing copper and tellurium;

(2) adjusting the pH value of the leaching solution to 1.5-2.5, diluting the copper content to 10-15g/L, precipitating for 2h, cooling to 30-40 ℃, and filtering for later use;

(3) and (3) adding the liquid obtained in the step (2) into an extraction box for extraction operation, selecting a hydroxyl-ketone extractant as the extractant, extracting to obtain a copper-containing extractant and a tellurium tetrachloride solution, and adding sulfuric acid into the copper-containing extractant for back extraction to obtain a copper sulfate solution.

2. The method for separating and purifying the crude cuprous telluride slag according to claim 1, wherein the method comprises the following steps: and (2) the solid-liquid ratio of the coarse cuprous telluride slag pulping in the step (1) is 1: 3-7.

3. The method for separating and purifying the crude cuprous telluride slag according to claim 1, wherein the method comprises the following steps: and (2) performing oxidation acid leaching twice in the step (1), namely adding the crude cuprous telluride slurry into acid liquor containing an oxidant after pulping to perform primary oxidation acid leaching to obtain acid leaching residue and primary leaching liquor, adding the acid leaching residue into the acid liquor containing the oxidant to perform secondary oxidation acid leaching to obtain secondary leaching liquor and filter residue, and mixing the primary leaching liquor and the secondary leaching liquor to obtain leaching liquor containing copper and tellurium.

4. The method for separating and purifying the crude cuprous telluride slag according to claim 1 or 3, wherein the method comprises the following steps: the acid solution in the step (1) is hydrochloric acid, sulfuric acid or a mixed acid of the hydrochloric acid and the sulfuric acid, and the oxidant is one of hydrogen peroxide, sodium chlorate and potassium permanganate.

5. The method for separating and purifying the crude cuprous telluride slag according to claim 4, wherein the method comprises the following steps: the mass concentration percentage of the sulfuric acid solution is 98%, the mass concentration percentage of the hydrochloric acid solution is 31-35%, the mass concentration percentage of the hydrogen peroxide solution is 29%, the mass concentration of the sodium chlorate is 50-70 g/L, and the mass concentration of the potassium permanganate solution is 30-60 g/L.

6. The method for separating and purifying the crude cuprous telluride slag according to claim 4, wherein the method comprises the following steps: the addition amount of the oxidant in the step (1) is 2-5L of oxidant per Kg of crude cuprous telluride slag slurry or 0.5-1.5L of oxidant per Kg of acid leaching slag, and the addition amount of the acid solution is 2-6L of acid solution per Kg of crude cuprous telluride slag slurry or 0.5-2L of acid solution per Kg of acid leaching slag.

7. The method for separating and purifying the crude cuprous telluride slag according to claim 1, wherein the method comprises the following steps: the volume percentage of the hydroxy crotch extractant in the step (3) is 20 percent.

Technical Field

The invention relates to the technical field of non-ferrous metal smelting, in particular to a method for separating and purifying crude cuprous telluride slag.

Background

Tellurium belongs to a rare dispersion element, and is widely applied to the metallurgy and chemical industry as an additive. In addition, tellurium plays an important role in the preparation of materials such as electronics, optics and the like in the modern high-tech field. Tellurium is often associated with minerals such as copper, lead and bismuth, and often few separate deposits of tellurium are present. At present, tellurium is mainly obtained from byproducts generated in the non-ferrous metal smelting process through comprehensive recovery, and copper anode slime and bismuth refining slag are main sources for industrial recovery of tellurium.

The method for pretreating the copper anode mud mainly comprises a sulfating roasting-water leaching process, an air stirring sulfuric acid direct leaching process, a low-temperature oxidizing roasting-dilute sulfuric acid leaching process, a sodium chlorate oxidizing leaching process, a hydrogen peroxide oxidizing process, a pressurized sulfuric acid leaching process and the like. The solution containing tellurium produced by the process is often added with copper powder to precipitate tellurium, so as to obtain cuprous telluride slag. The cuprous telluride slag is rich in tellurium and copper, and also contains part of precious metals such as gold and silver, and has extremely high economic value.

The existing method for recovering the cuprous telluride residues realizes the separation of copper and tellurium by a plurality of procedures of acid leaching, alkali dissolution, impurity removal, neutralization and alkali dissolution of crude cuprous telluride, and because the procedures are various, the material loss of each procedure is serious, and the discharged waste materials are correspondingly increased, the waste of raw and auxiliary materials and human resources is easily caused, the environmental protection problem in the production process is increasingly prominent, and a large amount of investment is required for corresponding environmental protection facilities, so that the environmental protection is influenced, and the control of the production cost is not facilitated. The report of directly carrying out alkali dissolution separation on the cuprous telluride residues also exists, but the process has a large amount of entrainment in the production process, cannot complete alkali dissolution, has low leaching rate and causes waste of acid and alkali.

In conclusion, the existing cuprous telluride slag recovery technology has the problems of long process, low product added value, low recovery rate, high investment cost, serious resource waste and the like.

Disclosure of Invention

In view of the above, the present invention aims to provide a method for separating and purifying cuprous telluride residues, which has the advantages of simple process flow, low production cost and high production efficiency.

In order to achieve the purpose, the invention provides the following technical scheme: a method for separating and purifying crude cuprous telluride slag comprises the following steps:

(1) pulping the crude cuprous telluride residues, adding the pulped crude cuprous telluride residues into acid liquor containing an oxidant, and performing oxidation acid leaching to remove impurities such as silver, selenium and the like in the crude cuprous telluride residues to obtain leachate containing copper and tellurium;

(2) adjusting the pH value of the leaching solution to 1.5-2.5, diluting the copper content to 10-15g/L, precipitating for 2h, cooling to 30-40 ℃, and filtering for later use;

(3) and (3) adding the liquid obtained in the step (2) into an extraction box for extraction operation, selecting a hydroxyl-ketone extractant as the extractant, extracting to obtain a copper-containing extractant and a tellurium tetrachloride solution, and adding sulfuric acid into the copper-containing extractant for back extraction to obtain a copper sulfate solution.

Further, the solid-liquid ratio of the coarse cuprous telluride slag pulping in the step (1) is 1: 3-7.

Preferably, the step (1) comprises two times of oxidizing and acid leaching operations, namely, after the crude cuprous telluride residue is pulped, adding the pulped crude cuprous telluride residue into acid liquor containing an oxidant to perform first oxidizing and acid leaching to obtain acid leaching residue and primary leaching liquid, adding the acid leaching residue into the acid liquor containing the oxidant to perform second oxidizing and acid leaching to obtain secondary leaching liquid and filter residue, and mixing the primary leaching liquid and the secondary leaching liquid to obtain leaching liquid containing copper and tellurium. The leaching content of copper and tellurium can be improved.

Further, the acid solution in the step (1) is one of hydrochloric acid, sulfuric acid or a mixed acid of the hydrochloric acid and the sulfuric acid, and the oxidant is one of hydrogen peroxide, sodium chlorate and potassium permanganate.

The mass concentration percentage of the sulfuric acid solution is 98%, the mass concentration percentage of the hydrochloric acid solution is 31-35%, the mass concentration percentage of the hydrogen peroxide solution is 29%, the mass concentration of the sodium chlorate is 50-70 g/L, and the mass concentration of the potassium permanganate is 30-60 g/L.

Furthermore, the addition amount of the oxidant in the step (1) is 2-5L oxidant/Kg of crude cuprous telluride slag slurry or 0.5-1.5L oxidant/Kg of acid leaching slag, and the addition amount of the acid solution is 2-6L acid solution/Kg of crude cuprous telluride slag slurry or 0.5-2L acid solution/Kg of acid leaching slag.

Further, the volume percentage of the hydroxyl crotch extractant in the step (3) is 20%.

Compared with the prior art, the method provided by the application comprises the steps of firstly, carrying out oxidation acid leaching on the crude cuprous telluride residues by using acid liquor, enabling most of copper and tellurium in materials to enter a liquid phase to obtain a leaching solution, and separating the leaching solution from silver, selenium and the like; then, the present application uses a hydroxyl extractant to extract the leachate, so that copper and tellurium are separated. The hydroximic extractant is particularly selective for copper, can extract copper in acidic solution without neutralization with a base, is less expensive to operate than other processes, and has better effect than any other processes. Meanwhile, the pH value of the leachate is adjusted to 1.5-2.5 before extraction, and the copper content is diluted to 10-15g/L, so that the influence of chloride ions in the leachate on the extraction effect is greatly relieved, and the separation and extraction rate of tellurium and copper elements is improved. The method can fully realize the complete separation of the copper and the tellurium, thereby achieving the aim of comprehensively recovering the copper and the tellurium.

The method for separating and purifying the crude cuprous telluride slag does not adopt the traditional processes of repeated acid leaching, neutralization and impurity removal and the like, and directly realizes the separation of tellurium and copper by selecting the extracting agent, thereby reducing the investment of equipment and shortening the process route. The method can solve the problems of high cost and multiple devices caused by separating the crude cuprous telluride slag through the conventional processes of acid leaching, neutralization, alkali dissolution, secondary neutralization, impurity removal, acid leaching and the like, and can reduce the problems of environmental pollution, incomplete separation and the like in the separation process.

In conclusion, the method has the advantages of short process route, less equipment investment, simple process flow, low requirement on equipment, environmental protection and the like, can better realize the separation and recovery of the tellurium copper raw material with low cost, and is easy for industrial production.

Detailed Description

In order to make those skilled in the art better understand the technical solution of the present invention, the following detailed description of the present invention is provided with reference to specific embodiments. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

The application provides a method for separating and purifying crude cuprous telluride slag, which comprises the following steps:

(1) pulping the crude cuprous telluride slag according to a solid-to-liquid ratio of 1: 3-7, adding the obtained product into a mixed acid solution of an oxidant solution and an acid solution, and carrying out oxidation acid leaching to remove impurities such as silver, selenium and the like in the crude cuprous telluride slag to obtain a leaching solution containing copper and tellurium; the preferable technical scheme is that the operation of oxidizing and acid leaching is carried out twice, namely, the crude cuprous telluride residue is added into a mixed acid solution after pulping for carrying out first oxidizing and acid leaching to obtain acid leaching residue and a primary leaching solution, then the acid leaching residue is added into the mixed acid solution for carrying out second oxidizing and acid leaching to obtain a secondary leaching solution and filter residue, the primary leaching solution and the secondary leaching solution are mixed to obtain a leaching solution containing copper and tellurium, and the secondary oxidizing and acid leaching can improve the leaching content of copper and tellurium.

(2) Adjusting the pH value of the leaching solution to 1.5-2.5, diluting the copper content to 10-15g/L, precipitating for 2h, cooling to 30-40 ℃, and filtering for later use; the operation of adjusting the pH value can slow down the influence of chloride ions in the leaching solution on the extraction effect, and improve the separation and extraction rate of tellurium and copper elements.

(3) And (3) adding the liquid obtained in the step (2) into an extraction box for extraction operation, wherein the extractant is a hydroxyl-ketone extractant with the volume percentage of 20%, a copper-containing extractant and a tellurium tetrachloride solution are obtained after extraction, and the copper-containing extractant is added with sulfuric acid for back extraction to obtain a copper sulfate solution. The hydroximic extractant is particularly selective for copper, can extract copper in acidic solution without neutralization with a base, is less expensive to operate than other processes, and has better effect than any other processes.

In the invention, in the step (1), one of hydrochloric acid, sulfuric acid or a mixed acid of the hydrochloric acid and the sulfuric acid is selected, and the oxidant is one of hydrogen peroxide, sodium chlorate and potassium permanganate.

The mass concentration percentage of the sulfuric acid solution is 98%, the mass concentration percentage of the hydrochloric acid solution is 31-35%, the mass concentration percentage of the hydrogen peroxide solution is 29%, the mass concentration of the sodium chlorate is 50-70 g/L, and the mass concentration of the potassium permanganate is 30-60 g/L.

In the invention, the addition amount of the oxidant in the step (1) is 2-5L oxidant/Kg of crude cuprous telluride slag slurry or 0.5-1.5L oxidant/Kg of acid leaching slag, and the addition amount of the acid solution is 2-6L acid solution/Kg of crude cuprous telluride slag slurry or 0.5-2L acid solution/Kg of acid leaching slag.

In the present invention, the hydroxy crotch extractant in the step (3) has a volume percentage of 20%.

In the invention, the crude cuprous telluride slag comprises unqualified products, processing leftover materials and/or waste materials of cuprous telluride which are generated in the synthesis and processing processes of cuprous telluride compounds and are used as intermediate alloys, and the unqualified products and the processing leftover materials are more preferably generated in the synthesis and processing processes of cuprous telluride compounds. In the present invention, before the cuprous telluride compound waste is recovered, the content of tellurium, copper and other elements in the cuprous telluride compound waste is determined by a method known to those skilled in the art, so as to ensure the smooth proceeding of the subsequent separation and recovery processes, which is not particularly limited in the present invention.

To further illustrate the present invention, the following examples are provided for illustration. The crude cuprous telluride slag used in the following examples of the invention is unqualified products and processing leftover materials produced in the synthesis and processing processes of cuprous telluride compounds.