CN118957288A - A treatment process for high-palladium anode mud - Google Patents

Abstract

The present application relates to the field of metallurgical technology, and in particular to a process for treating high-palladium anode mud. A process for treating high-palladium anode mud comprises the following steps: S1: anode mud roasting; S2: copper separation; S3: tellurium separation; S4: extraction; S5: gold separation; S6: silver separation. The technical solution of the present application has the advantages of improving the recovery rate of palladium element and improving the yield and purity of precious metals when treating copper anode mud with a high palladium content.

Description

Treatment process of high-palladium anode mud

Technical Field

The application relates to the technical field of metallurgy, in particular to a treatment process of high-palladium anode slime.

Background

Palladium is a silver noble metal with good physical and chemical properties and has wide application in industrial production and high-tech fields. The main application is as follows:

1. The automotive industry: palladium is one of the important components of the three-way catalyst converter, and can convert harmful substances in automobile exhaust into harmless substances and purify the environment.

2. The electronics industry: palladium is an important raw material for capacitors, resistors, sockets, connectors, etc., and a combination of palladium-silver alloy and palladium-iridium alloy can be used to fabricate high speed heads.

3. The chemical industry: palladium is an important catalyst for the production of ethylene, liquid crystal televisions, artificial precious stones, etc., and can also be used for the manufacture of ink-jet printer inks, etc.

Copper mine anode slime contains more palladium elements, and how to efficiently recycle the palladium elements in the copper mine anode slime is widely concerned, and the treatment method in the prior art is as follows:

1. sulfating anode mud in a certain proportion, adding the anode mud into a muffle furnace, and roasting at different stage temperatures.

2. Copper separation: ball milling and slurrying are carried out on the slag after roasting, and then the slag is placed in a reaction kettle for leaching copper and tellurium.

3. Separating gold: under the acidic condition, adding sodium chlorate for gold separation by chlorination, reducing with sodium sulfite to obtain gold platinum palladium coarse powder after the gold separation process, and purifying and refining.

4. Silver separation: adding sodium carbonate into the separated solid slag to remove lead, and adding ammonia water to separate silver.

However, the existing gold separation method is difficult to treat copper anode slime with too high palladium element content, and the existing method is used for treating the copper anode slime with too high palladium element content, so that excessive palladium residues in solid slag and low direct yield are caused, and therefore, a treatment process for the copper anode slime with too high palladium element content needs to be developed.

Disclosure of Invention

The application provides a treatment process of high-palladium anode slime, which aims to improve the recovery rate of palladium element and the yield and purity of noble metal when treating copper anode slime with high palladium content.

The application provides a treatment process of high-palladium anode mud, which comprises the following steps:

s1, roasting anode slime: mixing anode slime and sulfuric acid according to a certain proportion, continuously stirring and reacting for 2-3 hours at a rotating speed of 60r/min, and conveying slurry into a muffle furnace for roasting after the reaction is completed to obtain slag;

s2, copper separation: placing the slag obtained in the step S1 into deionized water, continuously stirring at a rotating speed of 60r/min for reaction for 0.5-1 hour, standing after stirring is completed to obtain supernatant and precipitate, flushing the precipitate with deionized water for multiple times, mixing flushing liquid and supernatant, and vacuum drying to obtain copper sulfate;

S3, tellurium separation: and (3) putting the precipitate obtained in the step (S2) into an acid solution, adding a catalyst, continuously stirring at a rotating speed of 60r/min for reaction for 0.5-1 hour, standing after stirring is finished to obtain a supernatant and a precipitate, flushing the precipitate for multiple times by using the acid solution, mixing the flushing liquid and the supernatant, and then carrying out vacuum drying to obtain tellurium oxide.

S4, extracting: putting the precipitate obtained in the step S3 into an acid solution of triisobutyl phosphine sulfide, continuously stirring at a rotating speed of 60r/min for reaction for 0.5-1 hour, standing after stirring is finished to obtain a supernatant and a precipitate, flushing the precipitate for multiple times by using the acid solution, mixing flushing liquid and the supernatant, and then drying in vacuum to obtain palladium salt;

S5, separating gold: adding the precipitate obtained in the step S4 into an acid solution, adding an oxidant, continuously stirring at a rotating speed of 60r/min for reaction for 1-2 hours, standing after stirring is completed to obtain supernatant and precipitate, flushing the precipitate for multiple times by using the acid solution, mixing flushing liquid and supernatant, adding a reducing agent, continuously stirring at a rotating speed of 60r/min for reaction for 1-2 hours, filtering and drying after the reaction is completed to obtain gold powder and platinum powder;

S6, silver separation: and (3) adding the precipitate obtained in the step (S5) into a sodium carbonate solution, continuously stirring at the rotating speed of 60r/min for reaction for 1-2 hours, standing after stirring is completed, obtaining supernatant and precipitate, adding the precipitate into a hydrochloric acid solution, continuously stirring at the rotating speed of 60r/min for reaction for 0.5-1 hour, filtering after the reaction is completed, adding the precipitate into ammonia water, continuously stirring at the rotating speed of 60r/min for reaction for 1-2 hours, and filtering after the reaction is completed, thus obtaining silver powder.

By adopting the technical scheme, compared with the traditional treatment process, the method has the greatest difference that the one-step extraction process is added before the gold separation step, the triisobutyl phosphine sulfide plays a role in dissolving palladium element by putting the precipitate into the triisobutyl phosphine sulfide, and more palladium element in the mixture is dissolved in the solvent, so that the content of the palladium element in the precipitate is greatly reduced, and the precipitate meets the requirements of the traditional treatment process, thereby the traditional treatment process is continuously adopted, the recovery rate of the palladium element is greatly improved, and the purity and the yield of the recovered noble metal in the subsequent step are also improved.

According to the application, the organic matters in the copper anode slime are removed by mixing the copper anode slime with sulfuric acid and then roasting, and meanwhile, the metal elements are converted into the sulfate form, so that deionized water can be simply used for dissolving the copper sulfate in the subsequent copper separation process, thereby conveniently removing copper elements with more content and facilitating the subsequent separation of other elements.

According to the application, under the action of an acid solution and a catalyst, tellurium in the precipitate is converted into tellurate ions to be dissolved in the solution, so that the tellurium is separated from the precipitate, and then the tellurium is evaporated from the solvent in a vacuum drying mode to form a tellurium oxide solid.

Gold and platinum are difficult to leach by using a common solution because of weak activity, and in the method, a plurality of elements such as gold, platinum, silver and the like are dissolved in the solution under an acidic environment through a strong oxidant, and then metal ions are subjected to reduction reaction through a reducing agent after the dissolution.

The lead and silver are relatively close in activity and are difficult to separate in a general mode, in the application, the lead sulfate in the precipitate is converted into the lead carbonate in a sodium carbonate solution leaching mode, the silver sulfate is difficult to be converted due to low solubility, the state of the silver sulfate is still kept, the lead carbonate reacts with hydrochloric acid, lead element is dissolved in the solution, the silver element is still kept in a solid state, and finally ammonia water is used for preparing the silver powder, so that the separation mode has higher separation degree.

In the invention, the mass ratio of the anode slime to the sulfuric acid in the step S1 is 1 (0.5-1).

By adopting the technical scheme, the mass ratio of the anode slime to the sulfuric acid is 1 (0.5-1) through multiple experiments of operators, the dosage of the sulfuric acid is too small, most metal elements are difficult to be converted into sulfate, the yield is greatly reduced, when the dosage of the sulfuric acid is too large, the solution forms suspension instead of slurry, and the thinner liquid is easy to be dangerous when being roasted in a muffle furnace. .

In the invention, the roasting mode in the step S1 is that the roasting is firstly carried out for 1 hour at 350-400 ℃, then for 1 hour at 500-550 ℃, and finally for 1 hour at 600-650 ℃.

By adopting the technical scheme, the copper anode slime contains more organic matters, a large amount of gas is easily generated in a short time during high-temperature roasting, equipment damage is easily caused, and operators are easily injured.

In the invention, the acid solution in the step S3 is one or a combination of more of hydrochloric acid and sulfuric acid, and the catalyst in the step S3 is one or a combination of more of sodium chloride, potassium chloride and sodium hypochlorite.

By adopting the technical scheme, in the application, the step S3 mainly has the catalytic effect of chloride ions, and the chloride ions need to be catalyzed in an acidic environment in order to have a better catalytic effect, so that the acid solution and the chloride are screened, and sodium hypochlorite can provide not only the chloride ions but also a certain oxidizing property after hydrolysis, and the catalytic effect in the application is excellent.

In the present invention, the acid solution in the step S4 is one or a combination of several of hydrochloric acid, sulfuric acid and nitric acid.

By adopting the technical scheme, the reaction in the step S4 can be performed in an acidic environment, sulfuric acid and hydrochloric acid can improve stronger acidity, nitric acid can provide acidity and strong oxidizing property, and the reaction product has excellent performance in the application.

In the invention, the acid solution in the step S5 is one or a combination of more of hydrochloric acid and sulfuric acid, the oxidant in the step S5 is one or a combination of more of hydrogen peroxide, sodium hypochlorite, sodium chlorate and potassium permanganate, and the reducing agent in the step S5 is sodium sulfite.

By adopting the technical scheme, the oxidant can exert stronger oxidation effect in an acidic environment, so that an operator screens proper acid and oxidant through multiple experiments, and in the subsequent reduction process, if the reduction effect of the reducing agent is stronger, gold and platinum are easily reduced into metal powder by using metal elements, so that the purity of noble metal is reduced, and multiple experiments of the operator prove that sodium sulfite is more proper to be used as the reducing agent in the application.

In the invention, the extractant triisobutyl phosphine sulfide in the step S4 is prepared from triisobutyl phosphine and elemental sulfur in a benzene solvent.

In the invention, the mole ratio of the triisobutyl phosphine to the elemental sulfur is 1: (1.05-1.2).

By adopting the technical scheme, the excessive addition of sulfur can ensure that the triisobutylphosphine is completely reacted, and the waste of raw materials is reduced.

In summary, the present application includes at least one of the following beneficial technical effects:

1. When the anode slime is treated, compared with the traditional treatment process, the method has the greatest difference that the one-step extraction process is added before the gold separation step, the triisobutyl phosphine sulfide plays a role in dissolving palladium element by putting the precipitate into the triisobutyl phosphine sulfide, and more palladium element in the mixture is dissolved in the solvent, so that the content of the palladium element in the precipitate is greatly reduced, and the precipitate meets the requirements of the traditional treatment process, thereby the traditional treatment process is continuously adopted, the recovery rate of the palladium element is greatly improved, and the purity and the yield of the recovered noble metal in the subsequent step are also improved.

2. The copper anode slime contains more organic matters, a large amount of gas is easy to generate in a short time during high-temperature roasting, equipment is easy to damage, and operators are easy to be injured.

3. In the application, the step S3 mainly has the catalytic effect of chloride ions, and the chloride ions need to be catalyzed in an acidic environment in order to have a better catalytic effect, so that the acid solution and the chloride are screened, and sodium hypochlorite can provide chloride ions and a certain oxidizing property after hydrolysis, and the catalytic effect is excellent in the application.

Detailed Description

The present application will be described in further detail with reference to the following specific details.

Examples

Example 1

A treatment process of high palladium anode mud comprises the following steps:

S1, roasting anode slime: mixing 100g of high-palladium anode slime and 100g of sulfuric acid according to a certain proportion, continuously stirring at a rotating speed of 60r/min for reaction for 2-3 hours, conveying slurry into a muffle furnace after the reaction is completed, roasting at 350-400 ℃ for 1 hour, roasting at 500-550 ℃ for 1 hour, and roasting at 600-650 ℃ for 1 hour to obtain slag;

S2, copper separation: placing the slag obtained in the step S1 into 500ml of deionized water, continuously stirring at a rotating speed of 60r/min for reaction for 0.5-1 hour, standing after stirring is completed to obtain supernatant and precipitate, flushing the precipitate with deionized water for multiple times, mixing flushing liquid and supernatant, and vacuum drying to obtain copper sulfate;

S3, tellurium separation: and (2) adding the precipitate obtained in the step (S2) into 200m10% hydrochloric acid solution, adding 5g of sodium chloride, continuously stirring at a rotating speed of 60r/min for reaction for 0.5-1 hour, standing after stirring is finished to obtain supernatant and precipitate, flushing the precipitate for multiple times by using an acid solution, mixing flushing liquid and supernatant, and vacuum drying to obtain tellurium oxide.

S4, extracting: adding the precipitate obtained in the step S3 into 100ml of 10% nitric acid solution of triisobutyl phosphine sulfide, continuously stirring at a rotating speed of 60r/min for reaction for 0.5-1 hour, standing after stirring is finished to obtain supernatant and precipitate, flushing the precipitate for multiple times by using an acid solution, mixing flushing liquid and supernatant, and vacuum drying to obtain palladium salt;

S5, separating gold: adding the precipitate obtained in the step S4 into 100ml of 20% sulfuric acid solution, adding 20g of sodium chlorate, continuously stirring at a rotating speed of 60r/min for reaction for 1-2 hours, standing after stirring is finished to obtain supernatant and precipitate, flushing the precipitate for multiple times by using 20% sulfuric acid solution, mixing flushing liquor and supernatant, adding 20g of sodium sulfite, continuously stirring at a rotating speed of 60r/min for reaction for 1-2 hours, filtering and drying after the reaction is finished to obtain gold powder and platinum powder;

S6, silver separation: and (3) adding the precipitate obtained in the step (S5) into 100ml of 10% sodium carbonate solution, continuously stirring at the rotating speed of 60r/min for reaction for 1-2 hours, standing after stirring is completed to obtain supernatant and precipitate, adding the precipitate into excessive hydrochloric acid solution, continuously stirring at the rotating speed of 60r/min for reaction for 0.5-1 hour, filtering after the reaction is completed, adding the precipitate into ammonia water, continuously stirring at the rotating speed of 60r/min for reaction for 1-2 hours, and filtering after the reaction is completed to obtain silver powder.

Comparative example 1 differs from example 1 in that there is no extraction process of step S4.

Examples 2 and 3 differ from example 1 in that the acid used in step S4 is different, as shown in the following table:

	Acid(s)
		Example 1	Nitric acid
Example 2	Hydrochloric acid
		Example 3	Sulfuric acid

Examples 4,5 and comparative example 2 differ from example 1 in the kind of acid and catalyst used in step S3, as shown in the following table:

	Acid(s)	Catalyst
			Example 1	Hydrochloric acid	Sodium chloride
Example 4	Sulfuric acid	Sodium chloride
			Example 5	Hydrochloric acid	Sodium hypochlorite
Comparative example 2	Deionized water	Sodium chloride

Performance test

The purity and yield calculations were performed on the products produced in each example and comparative example:

Purity: the products of each example and comparative example were dissolved in the corresponding solvents and then titrated to calculate the purity of the products.

Yield: the corresponding yield was calculated from the purity of the product.

The test results are shown in the following table:

conclusion: as can be seen from the data of example 1 and comparative example 1, the purity of the recovered noble metal is greatly improved when the high-palladium anode slime is treated compared with the conventional process, because palladium element in the anode slime is separated together in the conventional recovery process when the gold separation step is carried out, so that the metal palladium is mixed in noble metal powder to reduce the purity of the noble metal.

	Palladium element yield (%)	Purity of palladium element (%)
			Example 1	98	99.5
Example 2	96	99.3
			Example 3	94	99.3

Conclusion: as is clear from the data of examples 1,2 and 3, the recovery effect of the nitric acid as a solvent on the palladium element is better than that of hydrochloric acid and sulfuric acid when the palladium element is extracted in the step S4, and the nitric acid has stronger oxidizing property, so that the solid palladium element in the anode mud can be oxidized into palladium ions, and the yield of the palladium element is obviously improved.

	Refined selenium tellurium mixture purity (%)	Refined selenium tellurium mixture yield (%)
			Example 1	99.5	95
Comparative example 3	86.3	94

Conclusion: as can be seen from the data of example 1 and comparative example 3 in the above table, the addition of the sulfide salt in step S2 in the present application can greatly improve the purity of the product, because the sulfide precipitate is formed by the reaction of the metal ions in the solution with the sulfide ions by adding the sulfide salt to the solution, thereby facilitating the removal of the metal ions, thereby improving the purity of the product.

	Tellurium yield (%)	Tellurium purity (%)
			Example 1	96.2	99.7
Example 4	93.2	99.1
			Example 5	97.5	99.6
Comparative example 2	86.3	96.1

Conclusion: as is apparent from the data of examples 1, 4, 5 and comparative example 2, in the tellurium separation process of step S3, when the acid solution is hydrochloric acid and the catalyst is sodium hypochlorite, the yield and purity of tellurium element are higher, because in the process, chlorine ions are mainly used as catalytic effects, but in order to have excellent catalytic effects, the chlorine ions need to be catalyzed in an acidic environment, deionized water is used in comparative example 2 instead of hydrochloric acid, no acidic environment is provided, so that the yield and purity of tellurium element are greatly reduced, and sodium hypochlorite is used as the catalyst in example 5, sodium hypochlorite itself has strong oxidizing property, and chlorine ions are generated after decomposition, so that the catalyst has excellent catalytic effects in the application.

The foregoing embodiments are all preferred embodiments of the present application, and are not intended to limit the scope of the present application in any way, therefore: all equivalent changes in structure, shape and principle of the application should be covered in the scope of protection of the application.

Claims (8)

1. A treatment process of high palladium anode mud is characterized by comprising the following steps of: the method comprises the following steps:

s1, roasting anode slime: mixing anode slime and sulfuric acid according to a certain proportion, continuously stirring and reacting for 2-3 hours at a rotating speed of 60r/min, and conveying slurry into a muffle furnace for roasting after the reaction is completed to obtain slag;

s2, copper separation: placing the slag obtained in the step S1 into deionized water, continuously stirring at a rotating speed of 60r/min for reaction for 0.5-1 hour, standing after stirring is completed to obtain supernatant and precipitate, flushing the precipitate with deionized water for multiple times, mixing flushing liquid and supernatant, and vacuum drying to obtain copper sulfate;

S3, tellurium separation: putting the precipitate obtained in the step S2 into an acid solution, adding a catalyst, continuously stirring at a rotating speed of 60r/min for reaction for 0.5-1 hour, standing after stirring is finished to obtain a supernatant and a precipitate, flushing the precipitate for multiple times by using the acid solution, mixing the flushing liquid and the supernatant, and then carrying out vacuum drying to obtain tellurium oxide;

S4, extracting: putting the precipitate obtained in the step S3 into an acid solution of triisobutyl phosphine sulfide, continuously stirring at a rotating speed of 60r/min for reaction for 0.5-1 hour, standing after stirring is finished to obtain a supernatant and a precipitate, flushing the precipitate for multiple times by using the acid solution, mixing flushing liquid and the supernatant, and then drying in vacuum to obtain palladium salt;

S5, separating gold: adding the precipitate obtained in the step S4 into an acid solution, adding an oxidant, continuously stirring at a rotating speed of 60r/min for reaction for 1-2 hours, standing after stirring is completed to obtain supernatant and precipitate, flushing the precipitate for multiple times by using the acid solution, mixing flushing liquid and supernatant, adding a reducing agent, continuously stirring at a rotating speed of 60r/min for reaction for 1-2 hours, filtering and drying after the reaction is completed to obtain gold powder and platinum powder;

S6, silver separation: and (3) adding the precipitate obtained in the step (S5) into a sodium carbonate solution, continuously stirring at the rotating speed of 60r/min for reaction for 1-2 hours, standing after stirring is completed, obtaining supernatant and precipitate, adding the precipitate into a hydrochloric acid solution, continuously stirring at the rotating speed of 60r/min for reaction for 0.5-1 hour, filtering after the reaction is completed, adding the precipitate into ammonia water, continuously stirring at the rotating speed of 60r/min for reaction for 1-2 hours, and filtering after the reaction is completed, thus obtaining silver powder.

2. The process for treating high-palladium anode slime according to claim 1, which is characterized in that: the mass ratio of the anode slime to the sulfuric acid in the step S1 is 1 (0.5-1).

3. The process for treating high-palladium anode slime according to claim 1, which is characterized in that: the roasting mode in the step S1 is that the material is firstly roasted for 1 hour at 350-400 ℃, then roasted for 1 hour at 500-550 ℃, and finally roasted for 1 hour at 600-650 ℃.

4. The process for treating high-palladium anode slime according to claim 1, which is characterized in that: the acid solution in the step S3 is one or a combination of a plurality of hydrochloric acid and sulfuric acid, and the catalyst in the step S3 is one or a combination of a plurality of sodium chloride, potassium chloride and sodium hypochlorite.

5. The process for treating high-palladium anode slime according to claim 1, which is characterized in that: the acid solution in the step S4 is one or a combination of more of hydrochloric acid, sulfuric acid and nitric acid.

6. The process for treating high-palladium anode slime according to claim 1, which is characterized in that: the acid solution in the step S5 is one or a combination of more of hydrochloric acid and sulfuric acid, the oxidant in the step S5 is one or a combination of more of hydrogen peroxide, sodium hypochlorite, sodium chlorate and potassium permanganate, and the reducing agent in the step S5 is sodium sulfite.

7. The process for treating high-palladium anode slime according to claim 1, which is characterized in that: the extractant triisobutyl phosphine sulfide in the step S4 is prepared from triisobutyl phosphine and elemental sulfur in a benzene solvent.

8. The process for treating high-palladium anode slime according to claim 1, which is characterized in that: the mole ratio of the triisobutyl phosphine to the elemental sulfur is 1: (1.05-1.2).