CN107779599B - A kind of preparation and its application method of rare precious metal complex reducing agent - Google Patents

Abstract

The present invention relates to the preparations and its application method of a kind of rare precious metal complex reducing agent, using copper-bath as raw material, adjust solution acidity, it is heated to certain temperature, the stronger metal of reproducibility is added, keep system temperature, reaction after a certain period of time active compound copper powder, obtain the solution containing active compound copper powder and the stronger metal ion of reproducibility as rare precious metal complex reducing agent；It is added in the solution containing rare precious metal, is reduced directly rare precious metal；After solution after restoring rare precious metal adjusts acidity, it is incorporated again through the processed active copper smelting smoke dust of oxidizing roasting, the metal ion in ion or solution formed with the stronger metal of reproducibility forms the biggish co precipitation agent of specific surface area, the rare precious metal of High-rate sedimentation fine particles；Rare precious metal concentrate is obtained after separation of solid and liquid and containing miscellaneous lower copper-bath；Rare precious metal complex reducing agent provided by the invention efficiently restores rare precious metal and recycles rare precious metal, purifies copper-bath.

Description

Preparation and application method of a kind of rare precious metal composite reducing agent

technical field

The invention belongs to the field of metallurgy, in particular to the field of recycling rare and precious metals in non-ferrous metal copper smelting systems, and in particular relates to the preparation and use of a rare and precious metal composite reducing agent.

Background technique

Copper anode slime is a high-value by-product produced in the copper electrolytic refining process. It generally contains more rare and precious metals such as gold, silver, platinum, palladium, selenium, tellurium, and heavy metals such as copper, lead, bismuth, tin, and antimony. It is an important source of raw materials for the recovery of rare and precious metals and non-ferrous heavy metals; at present, the mature treatment process of copper anode slime is to use wet leaching or fire roasting pretreatment to remove copper, selenium, silver, tellurium, arsenic and other elements, and obtain Copper liquid and copper-separating slag, precious metals gold, platinum, and palladium are mainly enriched in copper-separating slag; copper-separating slag is leached gold, platinum, palladium by wet oxidation, or pyromelting copper-separating slag process to obtain Dole alloy, more Gold, platinum and palladium are leached from the anode slime obtained by the electrolysis of Al alloys by wet oxidation; the precious metal platinum and palladium are mainly enriched in the precious gold leaching solution, and after the gold-containing precious solution is recovered by immersion gold treatment, platinum and palladium are mainly enriched in the immersion gold after liquid.

There are many technologies for recovering gold, platinum and palladium in the liquid after gold immersion, mainly using zinc powder, sulfur dioxide, copper powder, sodium sulfite and other reducing agents to recover gold, platinum and palladium. Part of the reduction process has been industrialized and the effect is relatively ideal. The above reduction The agent is mainly used in the recovery of platinum and palladium in the liquid after gold immersion. The acid waste liquid after the recovery of precious metal platinum and palladium has basically no industrial value, and the requirements for introducing impurities into the system are relatively low. The acid waste liquid is mainly sent to the water treatment section. Recycling after neutralization, aeration, and purification processes. Zheng Yajie et al.’s application number is 201010266679.0 for an invention patent "a method for compound reduction of rare and precious metals in solution", which is mainly aimed at the liquid after gold immersion, adding chloride ions as a catalyst, through After adding sulfur dioxide, hydroxylamine hydrochloride and hydrazine hydrate are used as reducing agents to compositely reduce rare precious metals, and more chloride ions are introduced into the system; there is a lack of recovery technology for gold, platinum, and palladium in the copper separation solution of copper anode slime, and the liquid after copper separation of copper anode slime The main component is copper sulfate, and its copper content is generally 35-100g/L. It is mainly used for the production of cathode copper by copper electrowinning or the recovery of copper sulfate by-products by evaporation and crystallization. The reduction of platinum and palladium or the accumulation of ultrafine precious metal particles is poor, and many impurities are introduced into the system.

Contents of the invention

The purpose of the present invention is to overcome the deficiencies in the prior art and provide a preparation and preparation of a rare and precious metal composite reducing agent that can efficiently reduce rare and precious metals to recover gold, platinum, palladium, selenium and tellurium, and simultaneously purify the copper separation liquid or the liquid after gold precipitation. How to use it.

Technical scheme of the present invention is as follows:

A preparation method of a rare metal composite reducing agent, comprising the following steps:

Step 1: adding the copper sulfate solution into a reactor with a stirring device and a heating device, stirring and heating;

Step 2: adjusting the acidity of the copper sulfate solution under certain temperature conditions, using an acidity regulator to adjust the acidity of the copper sulfate solution to a specific range;

Step 3: Keep the temperature of the copper sulfate solution not less than 50°C, add metals with strong reducibility, and maintain the temperature of the system, and react to obtain active composite copper powder, which contains active composite copper powder and highly reducible metal ions. The solution is the dilute precious metal composite reducing agent.

Preferably, the copper sulfate solution described in step 1 is a solution prepared from analytically pure or industrially pure copper sulfate, or a copper separation solution obtained from pretreatment of copper anode slime.

Preferably, the concentration of copper ions in the copper sulfate solution described in step one is 2-100g/L.

Preferably, the certain temperature in step 2 is 50-95°C.

Preferably, the copper sulfate solution in the solution described in step 2 reaches a specific range of acidity of 0.05-200g/L; the acidity regulator is composed of one, two or three of sodium hydroxide, sodium carbonate, and sodium bicarbonate , or one, two or three of calcium hydroxide, calcium oxide, and calcium carbonate.

Preferably, the highly reducing metal described in Step 3 is a mixture of one, two or more of arsenic, antimony, bismuth, tin, and iron; the shape of the highly reducing metal is It is block, strip, granular or powder.

A method for using a rare and precious metal composite reducing agent, adding the rare and precious metal composite reducing agent obtained in step 3 into a solution containing rare and precious metals to reduce the rare and precious metals; the active composite copper powder reduces gold, platinum, palladium, selenium and tellurium in the solution The acidity of the solution after the reduction of rare metals is adjusted, and then mixed with active copper smelting fumes treated by oxidation and roasting, reacting for 0.5-2h under heating conditions, and combining with metal ions contained in the solution of rare and precious metals to form a large specific surface area The synergistic precipitant can precipitate fine particles of rare precious metals, and at the same time purify the copper-containing solution. After solid-liquid separation, the precious metal concentrate and the purified copper sulfate solution are obtained.

Preferably, the acidity of the solution after reducing the rare precious metal is 0.05-200g/L after the acidity of the solution is adjusted.

Preferably, the reaction is carried out for 0.5-2 hours under the heating conditions, and the temperature range of the heating conditions is 50-95°C.

Compared with prior art, the beneficial effect of the present invention is:

The present invention can effectively reduce and accumulate rare and precious metals by treating the copper separation liquid with the rare metal composite reducing agent, so that the ionic state and ultrafine particle rare and precious metals dissolved and dispersed in the copper separation liquid can be effectively reduced and enriched, and the key point is that it can Effectively purify the copper separation solution to reduce the impurity content, and obtain a rare precious metal concentrate and a copper separation solution with low impurity content suitable for electrodeposition of copper or evaporation and crystallization to recover copper sulfate; The solution, especially the acid leaching copper separation solution of copper anode slime, has the advantages of low cost, environmental protection, simplicity and high efficiency.

Description of drawings

Figure 1 is an industrial flow chart for the use of rare and precious metal composite reducing agents.

Figure 2 is the electrode reaction and standard electrode potential diagram

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

A preparation method of a rare metal composite reducing agent, comprising the following steps: Step 1, adding copper sulfate solution into a reactor with a stirring device and a heating device, stirring and heating; Step 2, adjusting the sulfuric acid solution under a certain temperature condition For the acidity of the copper solution, use an acidity regulator to adjust the acidity of the copper sulfate solution to a specific range; Step 3, keep the temperature of the copper sulfate solution not less than 50°C, add a metal with strong reducibility, and maintain the system temperature, the reaction will be active Composite copper powder, the obtained solution containing active composite copper powder and reducible metal ions is the rare precious metal composite reducing agent.

The copper sulfate solution described in step 1 is a solution prepared from analytically pure or industrially pure copper sulfate, or a copper separation solution obtained by pretreatment of copper anode slime, and the copper separation solution obtained by using copper anode slime pretreatment can be prepared Active composite copper powder simultaneously reduces rare precious metals; the concentration of copper ions in the copper sulfate solution described in step 1 is 2-100g/L; the certain temperature described in step 2 is 50-95°C; the solution described in step 2 The specific range of acidity of the copper sulfate solution is 0.05-200g/L; the acidity regulator is composed of one, two or three of sodium hydroxide, sodium carbonate, and sodium bicarbonate, regardless of the occurrence of filter residue, or It is composed of one, two or three of calcium hydroxide, calcium oxide, and calcium carbonate; the metal with strong reducibility described in step 3 is one or both of arsenic, antimony, bismuth, tin, and iron. more than one mixture; the shape of the metal with strong reducibility is block, strip, granular or powder, and the smaller metal particle size is conducive to accelerating the reaction rate and avoiding the reduction of the metal added by the active composite copper powder package. agent; a higher temperature is conducive to accelerating the reaction rate of adjusting the acidity of the solution, and a higher temperature is conducive to accelerating the reaction rate of reducing rare precious metals.

A method for using a rare and precious metal composite reducing agent, adding the rare and precious metal composite reducing agent obtained in step 3 into a solution containing rare and precious metals to reduce the rare and precious metals; the active composite copper powder reduces gold, platinum, palladium, selenium and tellurium in the solution The acidity of the solution after the reduction of rare metals is adjusted, and then mixed with active copper smelting fumes treated by oxidation and roasting, reacting for 0.5-2h under heating conditions, and combining with metal ions contained in the solution of rare and precious metals to form a large specific surface area The synergistic precipitant can precipitate fine particles of rare precious metals, and at the same time purify the copper-containing solution. After solid-liquid separation, the precious metal concentrate and the purified copper sulfate solution are obtained.

After the acidity of the solution is adjusted by the solution after reducing the rare metal, its acidity is 0.05-200g/L. The acidity range is consistent, which is conducive to reducing production costs, and the lower acidity is conducive to the co-precipitation of rare and precious metals; the reaction is 0.5-2h under the heating conditions, and the temperature range of the heating conditions is 50-95°C. Higher temperatures are conducive to Co-precipitant generation and co-precipitation of rare metals to purify copper-containing liquid.

A kind of preparation and using method of rare precious metal composite reducing agent, the reaction principle of rare precious metal composite reducing agent is: rare precious metal gold, platinum, palladium, selenium, tellurium and active metal copper, arsenic, antimony, bismuth, tin, iron, etc. Elements are involved in electrode reactions and electrode potentials. Referring to Figure 1 and Figure 2, the rare and precious metals gold, platinum, palladium, selenium, and tellurium all have high electrode potentials, and the electrode and graph potentials of copper are lower than those of rare and precious metals. The electrode potentials of , arsenic, antimony, iron, and tin are all lower than that of copper, so they can be used as reducing agents for rare and precious metals; adding bismuth, arsenic, antimony, and iron with strong reducibility to the solution containing copper sulfate and rare and precious metals Simple substances such as tin and tin can directly reduce rare and precious metals. Because these metals are inactive and have a small specific surface area, they mainly react with copper ions to form active composite copper powder; after the reduction of rare and precious metals by active composite copper powder is consumed, it can be used again. Bismuth, arsenic, antimony, iron, and tin can be reduced to active composite copper powder; at the same time, due to the strong oxidation of rare and precious metals and the presence of dissolved oxygen in the solution, Fe ²⁺ , SbO ⁺ , AsO ⁺ can be oxidized into high-valent ions , due to the addition of active copper smelting dust obtained by oxidation roasting, its main components are copper, arsenic, bismuth, tin, lead, etc., of which arsenic, antimony, and bismuth mainly exist in high-valence phases, which can form Fe ₂ with high specific surface area O ₃ .nH ₂ O, Sn(OH) ₂ SO ₄ , BiAsO ₄ , SbAsO ₄ and other colloidal adsorption and colloidal aging flocculent precipitation, rapidly aging under heating conditions to become particles with better precipitation properties, the particles are used as crystal seeds , and further cooperate to co-precipitate impurities such as arsenic, antimony, bismuth, tin and iron in the copper sulfate solution, so as to achieve the purpose of recovering rare and precious metals and co-evolving copper-containing solution.

Example 1

Weigh industrial-grade copper sulfate, prepare 100ml of copper sulfate solution with copper ion concentration of 35g/L and sulfuric acid acidity of 15g/L with tap water, add it to a three-necked flask with heating and stirring, and heat to 65°C. Add 0.06mol of iron powder, arsenic powder and bismuth powder in a ratio of 1:1:1, and maintain the temperature for 1.5h to obtain active composite copper powder;

Measure 1L of the copper-separated solution of copper anode slime, in which the copper ion content is 78g/L, and the acidity of sulfuric acid is 10g/L. The acidity of the solution is not adjusted, and the copper-separated solution is heated to 85°C under stirring conditions, and the composite The reducing agent is added to the copper separation liquid, and the temperature is maintained at 85°C for 1 hour of reaction, then 2 g of active copper smelting dust is added, and after 1 hour of reaction, the solid and liquid are separated to obtain precious metal concentrate and copper sulfate solution.

Table 1 Copper Sulfate Preparation Active Composite Copper Powder Reduction Precipitation Copper Separation Solution Result (mg/L)

Example 2

Measure 1L of copper anode slime copper separation solution, with copper ion concentration of 85g/L and sulfuric acid acidity of 0.5g/L, heat to 75°C under stirring conditions, add tin powder, antimony powder and The total amount of iron powder is 0.03mol, keep the temperature at 75°C for 2 hours, then add 3g of active copper smelting dust, raise the temperature to 80°C for 2 hours, and separate the solid and liquid to obtain rare precious metal concentrate and copper sulfate solution.

Table 2 Copper solution prepares active composite copper powder and reclaims rare precious metal results (mg/L)

Example 3

Measure 1L of gold immersion solution, in which the copper ion concentration is 2.5g/L and the hydrogen ion concentration is 4.34mol/L, heat it to 55°C under stirring conditions, and use sodium hydroxide and sodium carbonate with a mass ratio of 1:1:1 Condition the acidity of the solution with sodium bicarbonate solution to pH = 1, after heating the solution temperature to 90°C, add iron powder, tin powder, antimony powder, bismuth powder and arsenic in an amount of 1:1:1:1:1 The powder is 0.45mol in total, and the temperature is maintained for 2.5 hours to react, and then 5g of active copper smelting dust is added, and the reaction is completed for 0.5 hours, and the rare precious metal concentrate is obtained after solid-liquid separation.

Table 3 The results of the solution after reducing gold precipitation (mg/L)

Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments, or perform equivalent replacements for some of the technical features. Within the spirit and principles of the present invention, any modifications, equivalent replacements, improvements, etc., shall be included in the protection scope of the present invention.

Claims (7)

1. A method for using a rare precious metal composite reducing agent, characterized in that, comprising the following steps: Step 1: adding the copper separation solution obtained from the pretreatment of copper anode slime into a reactor equipped with a stirring device and a heating device, and stirring and heating; Step 2: adjusting the acidity of the copper separation solution obtained by the copper anode slime pretreatment under certain temperature conditions, and using an acidity regulator to adjust the acidity of the copper separation solution obtained by the copper anode slime pretreatment to within a specific range; Step 3: Keep the temperature of the copper separation solution obtained from the pretreatment of copper anode slime not less than 50°C, add metals with strong reducibility in the form of blocks, strips, granules or powders, and keep the system temperature to react to obtain activity Composite copper powder, the obtained solution containing active composite copper powder and reducible metal ions is the rare precious metal composite reducing agent; Step 4: Add the rare and precious metal composite reducing agent obtained in step 3 into the solution containing rare and precious metals to reduce the rare and precious metals; the active composite copper powder reduces the gold, platinum, palladium, selenium and tellurium in the solution; the solution after reducing the rare and precious metals is The acidity of the solution is adjusted, and then mixed with active copper smelting dust treated by oxidation and roasting, reacted for 0.5-2h under heating conditions, and combined with the metal ions contained in the solution of rare and precious metals to form a synergistic precipitant with a large specific surface area to precipitate fine particles Dilute precious metals, purify copper-containing solution at the same time, and obtain precious metal concentrate and purified copper sulfate solution after solid-liquid separation. 2. the method for using a kind of rare precious metal composite reducing agent as claimed in claim 1, it is characterized in that: the concentration of copper ions in the copper separation liquid obtained by the copper anode slime pretreatment described in step 1 is 2-100g/L . 3. The method for using a rare-precious metal composite reducing agent according to claim 1, characterized in that: the certain temperature in step 2 is 50-95°C. 4. the method for using a kind of rare and precious metal composite reducing agent as claimed in claim 1, is characterized in that: the specific range of acidity of the copper separation solution obtained by pretreatment of copper anode slime in the solution described in step 2 is 0.05-200g /L; the acidity regulator is composed of one, two or three of sodium hydroxide, sodium carbonate, and sodium bicarbonate, or one, two, or three of calcium hydroxide, calcium oxide, and calcium carbonate composition. 5. The method for using a rare and precious metal composite reducing agent as claimed in claim 1, wherein the metal with strong reducibility described in step 3 is one of arsenic, antimony, bismuth, tin, and iron or a mixture of two or more. 6 . The method for using a rare metal composite reducing agent according to claim 1 , wherein the acidity of the solution after reducing the rare metal is 0.05-200 g/L after adjusting the acidity of the solution. 7. The method for using a rare-precious metal composite reducing agent according to claim 1, characterized in that: the reaction is carried out for 0.5-2 hours under the heating condition, and the temperature range of the heating condition is 50-95°C.