A purification treatment process for copper anode slime

Abstract

The present application relates to copper anode slime comprehensive treatment technical field, especially in kind of copper anode slime's purification treatment process. Including the following steps: copper anode slime's pretreatment;Metal gel capture agent's preparation;Vacuum inductive desulfurization of copper arsenic tellurium anode slime is removed;The noble metal of desulfurized anode mud silicon is captured.The present application can increase the mutual contact of silicon dioxide, sodium carbonate, bismuth oxide and carbon fiber and metal elements in desulfurized anode gold mud in three-dimensional space by preparing metal gel capture agent, thereby increasing the contact area, strengthening the slagging reaction of silicon dioxide and sodium carbonate with impurity elements such as arsenic and antimony, and further enhancing the ability of carbon element to reduce bismuth oxide, so that bismuth can better capture gold and silver elements, and impurity metals can better aggregate in the slag, and the obtained bismuth-silver-gold alloy particles have high purity and good metal purification effect.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of comprehensive treatment of copper anode slime, and particularly relates to a purification treatment process of copper anode slime. BACKGROUND

[0002] The copper anode slime is a deposit containing impurities separated from the anode copper plate in the copper smelting process, and mainly includes oxides and sulfides of elements such as gold (Au), silver (Ag), arsenic (As), antimony (Sb), bismuth (Bi), tellurium (Te), selenium (Se) and copper. The purification treatment process of the copper anode slime aims to recover valuable metals (such as gold, silver, bismuth, selenium, etc.) from the impurity deposit and remove harmful substances (such as arsenic, antimony, etc.) to realize efficient recovery of resources and environmental protection.

[0003] At present, the main methods for treating copper anode slime at home and abroad include pyrometallurgical process, hydrometallurgical process, semi-hydrometallurgical process, combined metallurgy and smelting process, and Kaldo furnace pyrometallurgical process. Generally, the methods are divided into pyrometallurgical process and hydrometallurgical process. The hydrometallurgical process generally has problems such as complex process, many auxiliary materials and three wastes. The pyrometallurgical process mainly uses reducing agents such as coke, slagging agents such as silicon dioxide and sodium carbonate, and precious metal collectors to co-melt with the copper anode slime to separate the impurity metals and the precious metals, and then recover the precious metals. However, in this process, the reducing agent, the slagging agent and the precious metal collector have problems of density and mass, and the voids between the powders are large, which often leads to uneven distribution in the copper anode slime, and the metal ions cannot fully contact in the initial co-melting stage, thereby reducing the uniformity of the co-melt and affecting the separation of the impurity metals and the precious metals, and further affecting the recovery and purification rate of the precious metals. SUMMARY

[0004] In order to solve the above technical defects, the present application provides a purification treatment process of copper anode slime, which greatly reduces the content of impurities in the precious metals and improves the recovery and purification rate of the precious metals.

[0005] A purification treatment process of copper anode slime, comprising the following steps:

[0006] S1: Pretreatment of copper anode slime

[0007] The copper anode slime, the sulfuric acid solution, the zinc chloride and the ammonium sulfate are uniformly mixed to obtain copper anode slurry. After heating and warming, the copper anode slurry is placed in a mixed gas atmosphere of chlorine and oxygen, and is subjected to stirring and ultrasonic treatment. After cooling and pressure relief, filtration is performed to obtain filter residue and filtrate. The filter residue is dried to obtain a copper-arsenic-tellurium anode slime.

[0008] S2: Preparation of metal gel capturing agent

[0009] The tetraethyl orthosilicate, anhydrous ethanol and deionized water are placed in a container, after adjusting the pH, stirring is carried out after adding sodium carbonate and bismuth oxide, and a composite gel is obtained by standing; the composite gel is uniformly dispersed into carbon fiber felt by vacuum impregnation, after drying, it is soaked in anhydrous ethanol, and then dried to obtain a metal gel trapping agent;

[0010] S3: Vacuum inductive desulfurization of copper-arsenic-tellurium anode slime

[0011] The copper-arsenic-tellurium anode slime, concentrated sulfuric acid and hydrogen peroxide are uniformly mixed and stirred, and after heating, a ripened anode slime is obtained; the ripened anode slime is subjected to electromagnetic induction heating in a vacuum, and the generated gas is absorbed by a sodium sulfite solution; after cooling, a desulfurized anode slime is obtained.

[0012] S4: Precious metal trapping of desulfurized anode slime silicon

[0013] The desulfurized anode slime and the metal gel trapping agent are uniformly mixed and heated at high temperature to obtain a mixed metal material; the mixed metal material is crushed to obtain slag and bismuth-silver-gold alloy particles; the bismuth-silver-gold alloy particles are distilled and chlorinated to separate gold, to obtain a gold separation liquid and silver powder; the gold separation liquid is reduced by oxalic acid to obtain gold powder.

[0014] Further, the step S1 of pretreatment of the copper anode slime comprises the following steps:

[0015] S1.1: 8-10 parts by weight of copper anode slime are placed in the inner container of a reaction kettle, then a sulfuric acid solution with a concentration of 3.5-4 mol / L is added at a solid-liquid ratio of 1:(10-12), followed by the addition of zinc chloride and ammonium sulfate, the concentration of zinc chloride in the reaction inner container is controlled at 2.5-3 mol / L, and the concentration of ammonium sulfate is 1.5-2 mol / L; after stirring uniformly with a glass rod, a copper anode slime slurry is obtained;

[0016] S1.2: the reaction kettle containing the copper anode slime slurry is transferred to a reaction kettle equipped with an ultrasonic generator, a gas valve and a stirring device, the reaction kettle is sealed, the temperature is set to 60-65℃, the stirring speed is 200-250 rpm, and the ultrasonic frequency is 15-20 KHz; when heated to the set temperature, a mixed gas of chlorine and oxygen is introduced into the reaction kettle through the gas valve, so that the pressure in the kettle reaches 0.6-0.8 MPa; at this time, stop aeration, stir for 2-2.5 hours, then ultrasonic for 30-40 minutes, then naturally cool the reaction kettle to 30-35℃ and release the pressure to normal pressure, and then filter to obtain filter residue and filtrate; the filter residue is placed in a drying oven and dried at a temperature of 60-70℃ to obtain a copper-free arsenic-tellurium anode slime.

[0017] Further, the step S2 of preparation of the metal gel trapping agent comprises the following steps:

[0018] S2.1: Put tetraethyl orthosilicate, anhydrous ethanol and deionized water in a container in a mass ratio of 1:(3-4):(4-5), slowly drop into hydrochloric acid solution under stirring, adjust pH to 2-3, heat to 75-85℃ and continue to stir for 2-3 hours, then add ammonia water to adjust pH to 6-7, then add sodium carbonate and bismuth oxide, continue to stir for 15-20 minutes, then stand to obtain a composite gel;

[0019] S2.2: Take 1-2 parts by weight of carbon fiber felt with a pore size of 1-2 mm and place it in a mold, pour 3-4 parts by weight of the composite gel into the mold, then place it in a vacuum impregnation machine to uniformly disperse the composite gel into the carbon fiber felt by vacuum impregnation method, dry in an oven at 40-45℃ for 3-4 hours, then soak in anhydrous ethanol for 20-24 hours, then place it in an oven and dry at a temperature of 120-150℃ for 1.5-2 hours to obtain a metal gel trapping agent.

[0020] Further, step S3 of vacuum inductive desulfurization of the copper-arsenic-tellurium anode slime includes the following steps:

[0021] S3.1: Mix the copper-arsenic-tellurium anode slime prepared in step S1.2, 6-8 parts by weight of concentrated sulfuric acid with a concentration of 98% and 2-3 parts by weight of hydrogen peroxide, stir uniformly, then place it in an oven and heat at a temperature of 100-120℃ for 1-1.5 hours to obtain a cured anode slime;

[0022] S3.2: Place the cured anode slime in an electromagnetic induction heating tube furnace, the pressure in the furnace is extracted to 40-60kPa, air is introduced and the air flow rate is controlled at 200-220L / h, then heat at a rate of 10-15℃ / min to 380-400℃, maintain the temperature for 15-20 minutes of roasting, the gas discharged from the electromagnetic induction heating tube furnace is absorbed by 2-3 times of sodium sulfite solution, the solid material in the electromagnetic induction heating tube furnace is taken out and cooled to room temperature to obtain a desulfurized anode slime.

[0023] Further, step S4 of precious metal capture of silicon in the desulfurized anode slime includes the following steps:

[0024] S4.1: Place the desulfurized anode slime and the metal gel trapping agent in a mass ratio of 1:(1-1.5) in a high-speed blender and stir at a speed of 800-1000rpm, then place it in a tube furnace, introduce nitrogen for 3-5 minutes, seal the tube furnace, heat to 900-950℃ at a rate of 8-10℃ / min, then maintain the temperature for 6-8 hours, then cool to 30-45℃ to obtain a mixed metal material.

[0025] S4.2: The mixed metal material is placed in a crusher for 10-15 minutes, the particle size is controlled at 2-3 mm, then the metal particles are separated from the slag, and the bismuth-silver-gold alloy particles are obtained, the bismuth-silver-gold alloy particles are placed under a pressure of 3-4 Pa, distilled at a temperature of 1000-1050 DEG C for 2-2.5 hours, and the gold-rich silver slag is obtained, the gold-rich silver slag is separated by chlorination to obtain a gold separation liquid and silver powder, and the gold separation liquid is reduced by oxalic acid to obtain gold powder.

[0026] Further, in the mixed gas of chlorine and oxygen introduced into the reaction kettle in step S1.2, the volume ratio of chlorine to oxygen is 1:(4-5).

[0027] Further, in step S2.1, the mass fraction of sodium carbonate accounts for 10-20wt% of the total mass of tetraethyl orthosilicate, anhydrous ethanol and deionized water, and the mass fraction of bismuth oxide accounts for 30-50wt%.

[0028] Beneficial effects are: 1. In the process of preparing silica gel from tetraethyl orthosilicate, sodium carbonate and bismuth oxide are added to obtain a composite gel, and then the composite gel is dispersed into carbon fiber felt, so that the composite gel can fully and uniformly coat and penetrate the carbon fiber. The prepared metal gel capturing agent has certain strength and molding capacity, and the components of silica, sodium carbonate, bismuth oxide and carbon fiber are uniformly distributed. In the subsequent high-speed stirring process with desulfurized anode gold mud, the components can fully contact with the metal elements in the desulfurized anode gold mud in a three-dimensional space, increase the contact area, and maintain a solid state at the initial stage of slag making, avoiding uneven distribution of components due to mass reasons, strengthening the slag making reaction of silica and sodium carbonate with impurity elements such as arsenic and antimony, and further enhancing the ability of carbon element to reduce bismuth oxide, so that bismuth can better capture gold and silver elements, and impurity metals can better aggregate in the slag, and the obtained bismuth-silver-gold alloy particles have high Au and Ag purity and good metal purification effect.

[0029] 2. The copper anode slime is subjected to leaching treatment by constructing a sulfuric acid-zinc chloride-ammonium sulfate leaching system, and in the high-pressure environment of the introduced chlorine and oxygen, Ag element is easy to combine with Cl - to form AgCl precipitation, Pb combines with sulfate to form PbSO4 precipitation, Au element is stable and does not react, Se element forms Ag2Se precipitation with Ag, and all are enriched in the filter residue, while Cu element is converted into CuSO4 in the acidic system, and As, Sb, Bi and Te are also leached in the chlorine salt system and the high-pressure environment of chlorine and oxygen. The application introduces zinc ions which can form soluble complexes with As and Sb, promoting the leaching of As and Sb first, and then dissolving in the filtrate, reducing the components of impurities in the copper-tellurium-arsenic anode slime, thereby avoiding interference with the subsequent recovery of precious metals.

[0030] 3、The application can volatilize selenium oxide at a lower boiling temperature in a vacuum environment by mixing and aging the copper-arsenic-tellurium anode slime, concentrated sulfuric acid and hydrogen peroxide, and adding hydrogen peroxide as an oxidizing agent to prevent insufficient oxidation of selenium in a vacuum environment and affect the purification effect, thereby greatly improving the recovery rate of selenium. BRIEF DESCRIPTION OF DRAWINGS

[0031] Figure 1 A purification treatment process flowchart of the copper anode slime used in the embodiments of the application. DETAILED DESCRIPTION

[0032] The technical solutions in the embodiments of the application will be described clearly and completely below with reference to the drawings in the embodiments of the application. Obviously, the described embodiments are only part of the embodiments of the application, rather than all the embodiments of the application. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the application.

[0033] The main chemical components (wt%) of the copper anode slime in the following embodiments of the application are as follows: Cu 17.8, Se 8.34, Te 2.17, Sb 1.69, Bi 0.13, As 1.54, Pb 2.45, Ni 3.07, Au 0.14, and Ag 20.25.

[0034] Embodiment 1

[0035] A purification treatment process of copper anode slime, as shown in Figure 1 , includes the following steps:

[0036] S1: Pretreatment of the copper anode slime

[0037] S1.1: 8 parts by weight of the copper anode slime is placed in the inner container of a reaction kettle, then a sulfuric acid solution with a concentration of 3.5 mol / L is added at a solid-liquid ratio of 1:10, followed by the addition of zinc chloride and ammonium sulfate, the concentration of zinc chloride in the reaction inner container is controlled to be 2.5 mol / L, and the concentration of ammonium sulfate is 1.5 mol / L, and the copper anode slime slurry is obtained after uniform stirring with a glass rod;

[0038] S1.2: The reactor liner containing the copper anode slime slurry was transferred to a reactor equipped with an ultrasonic generator, a gas valve and a stirring device, the reactor was sealed, the temperature was set to 60°C, the stirring speed was 200 rpm, the ultrasonic frequency was 15 KHz, after heating to the set temperature, a mixed gas with a volume ratio of chlorine gas to oxygen gas of 1:4 was introduced into the reactor through the gas valve, the pressure in the reactor was raised to 0.6 MPa, at this time the aeration was stopped, stirring was carried out for 2 hours and then ultrasonic treatment was carried out for 30 minutes, then the reactor was naturally cooled to 30°C and depressurized to normal pressure, filtration was carried out to obtain filter residue and filtrate, the filter residue was placed in a drying box and dried at a temperature of 60°C, and a copper-depleted tellurium-arsenic anode slime was obtained.

[0039] S2: Preparation of metal gel capture agent

[0040] S2.1: Tetraethyl orthosilicate, anhydrous ethanol and deionized water were placed in a container in a mass ratio of 1:3:4, hydrochloric acid solution was slowly added dropwise under stirring, the pH was adjusted to 2, heating was carried out to 75°C, the temperature was maintained and stirring was continued for 2 hours, then ammonia water was added dropwise to adjust the pH to 6, then 10 wt% sodium carbonate and 30 wt% bismuth oxide were added, stirring was continued for 15 minutes, then standing was carried out to obtain a composite gel;

[0041] S2.2: 2 parts by weight of carbon fiber felt with a pore size of 1 mm were placed in a mold, 4 parts by weight of the composite gel were poured into the mold, then the mold was placed in a vacuum impregnation machine to uniformly disperse the composite gel into the carbon fiber felt by vacuum impregnation, drying was carried out in an oven at 40°C for 3 hours, then the carbon fiber felt was soaked in anhydrous ethanol for 20 hours, then drying was carried out in an oven at a temperature of 120°C for 1.5 hours, and a metal gel capture agent was obtained.

[0042] S3: Vacuum inductive desulfurization of copper-depleted arsenic-tellurium anode slime

[0043] S3.1: The copper-depleted arsenic-tellurium anode slime obtained in step S1.2, 6 parts by weight of concentrated sulfuric acid with a concentration of 98%, and 2 parts by weight of hydrogen peroxide were mixed and stirred uniformly, then the mixture was placed in an oven and heated at a temperature of 100°C for 1 hour to obtain a cured anode slime;

[0044] S3.2: The cured anode slime was placed in an electromagnetic induction heating tube furnace, the pressure in the furnace was drawn to 40 kPa, air was introduced and the air flow rate was controlled at 200 L / h, then the temperature was raised to 380°C at a temperature rise rate of 10°C / min, and holding was carried out for 15 minutes of roasting, the gas discharged from the electromagnetic induction heating tube furnace was absorbed twice by sodium sulfite solution, the solid material in the electromagnetic induction heating tube furnace was taken out and cooled to room temperature, and a desulfurized anode slime was obtained.

[0045] S4: Precious metal capture of silicon in desulfurized anode slime

[0046] S4.1: Put the deselenized anode slime and the metal gel capturing agent in a high-speed blender at a mass ratio of 1:1 and stir at a speed of 800 rpm, then put them into a tube furnace, seal the tube furnace after purging with nitrogen for 3 minutes, heat to 900℃ at a rate of 8℃ / min and keep for 6 hours, then cool to 30℃, to obtain a mixed metal material;

[0047] S4.2: Put the mixed metal material into a crusher and crush for 10 minutes, control the particle size to be 2mm, then pick and separate the metal particles from the slag to obtain bismuth-silver-gold alloy particles, put the bismuth-silver-gold alloy particles under a pressure of 3Pa and distill at a temperature of 1000℃ for 2 hours to obtain a gold-rich silver slag, separate the gold from the gold-rich silver slag by chlorination to obtain a gold separation liquid and silver powder, and reduce the gold separation liquid with oxalic acid to obtain gold powder.

[0048] Example 2

[0049] A purification process for copper anode slime, as shown in Figure 1 , comprising the following steps:

[0050] S1: Pretreatment of copper anode slime

[0051] S1.1: Put 10 parts by weight of copper anode slime into the inner container of a reaction kettle, then add a sulfuric acid solution with a concentration of 4 mol / L at a solid-liquid ratio of 1:12, then add zinc chloride and ammonium sulfate in sequence, control the concentration of zinc chloride in the reaction inner container to be 3 mol / L, and the concentration of ammonium sulfate to be 2 mol / L, stir uniformly with a glass rod to obtain a copper anode slime slurry;

[0052] S1.2: Transfer the reaction kettle inner container containing the copper anode slime slurry to a reaction kettle equipped with an ultrasonic generator, a gas valve and a stirring device, seal the reaction kettle, set the temperature to 60℃, the stirring speed to 200 rpm and the ultrasonic frequency to 15KHz, when heated to the set temperature, pass a mixed gas of chlorine and oxygen with a volume ratio of 1:5 into the reaction kettle to make the pressure in the kettle reach 0.6MPa, at this time stop aeration, stir for 2 hours and then ultrasonic for 30 minutes, then naturally cool the reaction kettle to 30℃ and release the pressure to normal pressure, and then filter to obtain a filter residue and a filtrate, put the filter residue in a drying oven and dry at a temperature of 60℃ to obtain a copper-removed tellurium-arsenic anode slime.

[0053] S2: Preparation of metal gel capturing agent

[0054] S2.1: Tetraethyl orthosilicate, anhydrous ethanol and deionized water were placed in a container in a mass ratio of 1:4:5, and hydrochloric acid solution was slowly added dropwise under stirring, the pH was adjusted to 2, heated to 75℃ and continued to stir for 2 hours, then ammonia water was added to adjust the pH to 6, then 20wt% sodium carbonate and 50wt% bismuth oxide were added, and continued to stir for 15 minutes, then placed to obtain a composite gel;

[0055] S2.2: 1 part by weight of carbon fiber felt with a pore size of 2mm was placed in a mold, 3 parts by weight of the composite gel was poured into the mold, then placed in a vacuum impregnation machine to uniformly disperse the composite gel into the carbon fiber felt by vacuum impregnation method, dried in an oven at 40℃ for 3 hours, then soaked in anhydrous ethanol for 20 hours, then placed in an oven at a temperature of 120℃ for 1.5 hours to obtain a metal gel trapping agent.

[0056] S3: Vacuum inductive desulfurization of copper-arsenic-tellurium anode slime

[0057] S3.1: The copper-arsenic-tellurium anode slime prepared in step S1.2, 8 parts by weight of concentrated sulfuric acid with a concentration of 98% and 3 parts by weight of hydrogen peroxide were mixed and stirred uniformly, then placed in an oven and heated at a temperature of 100℃ for 1 hour to obtain a cured anode slime;

[0058] S3.2: The cured anode slime was placed in an electromagnetic induction heating tube furnace, the pressure in the furnace was extracted to 40kPa, air was introduced and the air flow rate was controlled at 200L / h, then the temperature was increased to 380℃ at a heating rate of 10℃ / min, and the temperature was maintained for 15 minutes of roasting, the gas discharged from the electromagnetic induction heating tube furnace was absorbed twice by sodium sulfite solution, and the solid material in the electromagnetic induction heating tube furnace was taken out and cooled to room temperature to obtain a desulfurized anode slime.

[0059] S4: Precious metal trapping of silicon in desulfurized anode slime

[0060] S4.1: The desulfurized anode slime and the metal gel trapping agent were placed in a high-speed blender in a mass ratio of 1:1.5 and stirred at a speed of 800rpm, then placed in a tube furnace, sealed after introducing nitrogen for 3 minutes, heated to 900℃ at a heating rate of 8℃ / min, and then maintained for 6 hours, then cooled to 30℃ to obtain a mixed metal material;

[0061] S4.2: The mixed metal material was placed in a crusher and crushed for 10 minutes, the crushing particle size was controlled at 2mm, then the metal particles and the slag were selected and separated to obtain bismuth-silver-gold alloy particles, the bismuth-silver-gold alloy particles were placed under a pressure of 3Pa and distilled at a temperature of 1000℃ for 2 hours to obtain a gold-rich silver slag, the gold-rich silver slag was chlorinated to obtain a gold separation liquid and silver powder, and the gold separation liquid was reduced by oxalic acid to obtain gold powder.

[0062] Example 3

[0063] A purification treatment process for copper anode slime, as shown, comprising the following steps: Figure 1

[0064] S1: Pretreatment of copper anode slime

[0065] S1.1: 8 parts by weight of copper anode slime is placed in the inner container of the reaction kettle, then a sulfuric acid solution with a concentration of 3.5 mol / L is added at a solid-liquid ratio of 1:10, followed by the addition of zinc chloride and ammonium sulfate, the concentration of zinc chloride in the reaction inner container is controlled at 2.5 mol / L, and the concentration of ammonium sulfate is 1.5 mol / L, after stirring uniformly with a glass rod, a copper anode slime slurry is obtained;

[0066] S1.2: The reaction kettle containing the copper anode slime slurry is transferred to a reaction kettle equipped with an ultrasonic generator, a gas valve and a stirring device, the reaction kettle is sealed, the temperature is set to 65°C, the stirring speed is 250 rpm, and the ultrasonic frequency is 20 KHz, when heated to the set temperature, a mixed gas with a volume ratio of chlorine to oxygen of 1:4 is introduced into the reaction kettle through the gas valve, the pressure in the kettle reaches 0.8 MPa, at this time the aeration is stopped, stirring for 2.5 hours and ultrasonic for 40 minutes, then the reaction kettle is naturally cooled to 35°C and depressurized to normal pressure, filtration is performed to obtain filter residue and filtrate, the filter residue is placed in a drying oven at a temperature of 70°C, and the copper-removed tellurium-arsenic anode slime is obtained.

[0067] S2: Preparation of metal gel capture agent

[0068] S2.1: Tetraethyl orthosilicate, anhydrous ethanol and deionized water are placed in a container at a mass ratio of 1:3:4, slowly drop into hydrochloric acid solution under stirring, adjust pH to 3, heat to 85°C and continue stirring for 3 hours, then add 10wt% sodium carbonate and 30wt% bismuth oxide, continue stirring for 20 minutes, then stand to obtain a composite gel;

[0069] S2.2: 2 parts by weight of carbon fiber felt with a pore size of 1 mm is placed in a mold, 4 parts by weight of composite gel is poured into the mold, then placed in a vacuum impregnation machine to uniformly disperse the composite gel into the carbon fiber felt by vacuum impregnation method, dried in an oven at 45°C for 4 hours, then soaked in anhydrous ethanol for 24 hours, then placed in an oven at a temperature of 150°C for 2 hours, and the metal gel capture agent is obtained.

[0070] S3: Vacuum inductive desulfurization of copper-removed arsenic-tellurium anode slime

[0071] ​S3.1: The copper and arsenic tellurium removed anode slime prepared in step S1.2, 6 parts by weight of concentrated sulfuric acid with a concentration of 98%, and 2 parts by weight of hydrogen peroxide were mixed and stirred uniformly, and then placed in an oven and heated at a temperature of 120°C for 1.5 hours to obtain a ripened anode slime;

[0072] S3.2: The ripened anode slime was placed in an electromagnetic induction heating tube furnace, the pressure in the furnace was extracted to 60 kPa, air was introduced and the air flow rate was controlled at 220 L / h, and then the temperature was raised to 400°C at a temperature raising rate of 15°C / min, and the roasting was carried out for 20 minutes, the gas passing out of the electromagnetic induction heating tube furnace was absorbed by sodium sulfite solution for 3 times, and the solid material in the electromagnetic induction heating tube furnace was taken out and cooled to room temperature to obtain a selenium removed anode slime.

[0073] S4: Precipitation of precious metals from selenium removed anode slime

[0074] S4.1: The selenium removed anode slime and the metal gel capturing agent were placed in a high-speed blender at a mass ratio of 1:1 and stirred uniformly at a stirring speed of 1000 rpm, and then placed in a tube furnace, sealed after introducing nitrogen for 5 minutes, heated to 950°C at a temperature raising rate of 10°C / min, and then kept for 8 hours, and then cooled to 45°C to obtain a mixed metal material;

[0075] S4.2: The mixed metal material was placed in a crusher and crushed for 15 minutes, the crushing particle size was controlled at 3 mm, and then the metal particles and the slag were selected and separated to obtain bismuth-silver-gold alloy particles, the bismuth-silver-gold alloy particles were placed under a pressure of 4 Pa and distilled at a temperature of 1050°C for 2.5 hours to obtain a gold and silver rich slag, the gold and silver rich slag was chlorinated to obtain a gold separated liquid and silver powder, and the gold separated liquid was reduced by oxalic acid to obtain gold powder.

[0076] Comparative Example 1

[0077] Comparative Example 1 is different from Example 1 in that step S2 is removed in Comparative Example 1, and in step S4.1, the metal gel capturing agent is replaced with an equal mass of a mixed powder of coke, sodium carbonate, silicon dioxide, and bismuth oxide with a mass ratio of 1:10:10:30, and the remaining steps are the same as those in Example 1.

[0078] Comparative Example 2

[0079] Comparative Example 2 is different from Example 1 in that in step S1.1, zinc chloride and ammonium sulfate are replaced with an equal mass of sodium chloride and sodium sulfate, and the remaining steps are the same as those in Example 1, and the remaining steps are the same as those in Example 1 to obtain a copper and tellurium removed anode slime.

[0080] Comparative Example 3

[0081] Compared with Example 1, the difference of Comparative Example 3 is that, the step S1.2 is removed in Comparative Example 3, the copper anode slime slurry prepared in step S1.1 is directly subjected to heating treatment at 60℃ under oxygen atmosphere, and the remaining steps are the same as those of Example 1, to obtain the tellurium-arsenic anode slime after copper removal.

[0082] Comparative Example 4

[0083] Compared with Example 1, the difference of Comparative Example 4 is that, the step S3 is removed in Comparative Example 4, the tellurium-arsenic anode slime after copper removal prepared in step S1.2 is directly subjected to roasting treatment at 380℃ under the condition of oxygen flow rate of 200 L / h, and the remaining steps are the same as those of Example 1, to obtain the anode slime after selenium removal.

[0084] Experiment 1: 6 portions of 1000g copper anode slime were taken, every three portions as a group were divided into two groups, one group corresponds to Example 1, and the other group corresponds to Comparative Example 1, each portion of each group was prepared into bismuth-silver-gold alloy particles by the process of Example 1 and Comparative Example 1 respectively, and the purity of Au and Ag after removing bismuth element was measured by ICP-MS characterization to avoid the inaccuracy of data caused by bismuth in the subsequently added metal gel capturing agent, the data was recorded and made into a table as shown in Table 1, it can be seen that the purity of gold in Example 1 is higher than that of Comparative Example 1, which can prove that adding metal gel capturing agent to the selenium-removed anode gold slime for slagging reaction can strengthen the slagging reaction of silicon dioxide and sodium carbonate with impurity elements such as arsenic and antimony, and make bismuth better capture gold and silver elements, thereby increasing the metal purification effect.

[0085] Table 1: Purity of Au and Ag

[0086] Purity / % Au Ag Example 1 0.68 99.26 Comparative Example 1 0.67 98.25

[0087] Experiment 2: 9 portions of 1000g copper anode slime were taken, every three portions as a group were divided into three groups, one group corresponds to Example 1, one group corresponds to Comparative Example 2, and one group corresponds to Comparative Example 3, each portion of each group was prepared into filtrate by the process of Example 1, Comparative Example 2 and Comparative Example 3 respectively, the content of Cu, Sb and As impurity metals in the filtrate was measured by ICP-MS characterization, the average value of each group was calculated, and then the impurity metal leaching rate was calculated, impurity metal leaching rate = average value of impurity metal content in filtrate / average value of impurity metal content in copper anode slime x 100%, and a table was made as shown in Table 2, it can be seen that the impurity metal leaching rate of Example 1 is higher than that of Comparative Examples 2-3, which can prove that the construction of sulfuric acid-zinc chloride-ammonium sulfate leaching system and heating in high-pressure gas environment of chlorine and oxygen can improve the leaching rate of Cu, Sb and As.

[0088] Table 2: Impurity metal leaching rate

[0089] Impurity metal leaching / % Cu Sb As Example 1 99.83 98.98 96.23 Comparative Example 2 97.12 97.34 95.54 Comparative Example 3 96.23 97.02 95.15

[0090] Experiment three: take 6 portions of 1000g copper anode slime, every three portions as a group, divided into two groups, one group corresponds to example 1, and the other group corresponds to comparative example 4, each portion of each group is prepared by the process of example 1 and comparative example 4 respectively to obtain deselenium anode slime, the selenium metal content in which is measured by ICP-MS characterization, the average value of each group is calculated, then compared with the average content of the above ingredients in the copper anode slime, the direct recovery rate of selenium is calculated, the direct recovery rate of selenium = 1-deselenium anode slime selenium metal content / copper anode slime selenium metal content x 100%, a table is made, as shown in table 3, it can be seen that the direct recovery rate of selenium in example 1 is higher than that in comparative example 4, which can prove that vacuum inductive deselenium can greatly improve the recovery rate of selenium.

[0091] Table 3: direct recovery rate of selenium

[0092] Copper anode slime Example 1 Comparative Example 4 Selenium content / g 83.4 80.6 75.7 Direct yield of selenium / % 96.6 90.8

[0093] The above examples are only illustrative of the principles and effects of the present application, and are not intended to limit the present application. Any person skilled in the art can modify or change the above examples without departing from the spirit and scope of the present application. Therefore, all equivalent modifications or changes completed by those skilled in the art without departing from the spirit and technical thought disclosed by the present application should be covered by the claims of the present application.

Claims

1. A copper anode slime purification process, characterized in that: The following steps are involved: S1: Pretreatment of copper anode slime The copper anode mud, sulfuric acid solution, zinc chloride and ammonium sulfate are uniformly mixed to obtain a copper anode mud slurry, the copper anode mud slurry is heated and placed in a mixed gas atmosphere of chlorine and oxygen, stirred and ultrasonically treated, cooled and depressurized, and then filtered to obtain a filter residue and a filtrate, and the filter residue is dried to obtain a copper-removed arsenic-tellurium anode mud; S2: Preparation of metal gel capture agent Place tetraethyl orthosilicate, anhydrous ethanol and deionized water in a container at a mass ratio of 1: (3-4): (4-5), slowly add hydrochloric acid solution while stirring to adjust the pH to 2-3, heat to 75-85 ° C, maintain the temperature and continue stirring for 2-3 hours, then add ammonia water to adjust the pH to 6-7, then add 10-20wt% of sodium carbonate and 30-50wt% of bismuth oxide based on the total mass of tetraethyl orthosilicate, anhydrous ethanol and deionized water, and continue stirring for 15-20 minutes. The mixture was then allowed to stand to obtain a composite gel. 1-2 parts by weight of carbon fiber with a pore size of 1-2 mm was placed in a mold, and 3-4 parts by weight of the composite gel was poured into the mold. The mixture was then placed in a vacuum impregnation machine to evenly disperse the composite gel into the carbon fiber felt by vacuum impregnation. The mixture was dried in an oven at 40-45°C for 3-4 hours, and then immersed in anhydrous ethanol for 20-24 hours. The mixture was then placed in an oven at 120-150°C and dried for 1.5-2 hours to obtain a metal gel capture agent. S3: Vacuum induction deselenization of copper-arsenic-tellurium anode mud The copper-removed arsenic-tellurium anode mud, concentrated sulfuric acid and hydrogen peroxide are mixed and stirred uniformly, and heated to obtain mature anode mud. The mature anode mud is subjected to electromagnetic induction heating in a vacuum, and the generated gas is absorbed by a sodium sulfite solution. The solid matter is cooled to obtain the deselenized anode mud. S4: Precious Metal Capture of Deselenized Anode Mud Silicon The deselenium-removed anode mud and the metal gel capture agent are mixed evenly and then heated to 900-950°C to obtain a mixed metal material. The mixed metal material is crushed to obtain slag and bismuth-silver-gold alloy particles. The bismuth-silver-gold alloy particles are distilled and subjected to chlorination to obtain gold separation liquid and silver powder. The gold separation liquid is reduced with oxalic acid to obtain gold powder.

2. The copper anode slime purification process according to claim 1, characterized in that: Step S1: Pretreatment of copper anode slime, comprising the following steps: S1.1: Place 8-10 parts by weight of copper anode mud in the inner container of a reactor, then add a sulfuric acid solution with a concentration of 3.5-4 mol / L at a solid-to-liquid ratio of 1:(10-12), then add zinc chloride and ammonium sulfate in sequence, controlling the concentration of zinc chloride in the inner container to be 2.5-3 mol / L and the concentration of ammonium sulfate to be 1.5-2 mol / L, and stir evenly with a glass rod to obtain a copper anode mud slurry; S1.2: Transfer the inner tank of the reactor filled with copper anode mud to a reactor equipped with an ultrasonic generator, an air valve and a stirring device, seal the reactor, set the temperature to 60-65℃, the stirring speed to 200-250rpm, and the ultrasonic frequency to 15-20KHz. After heating to the set temperature, introduce a mixed gas of chlorine and oxygen into the reactor through the air valve to make the pressure in the reactor reach 0.6-0.8MPa. At this time, stop ventilation, stir for 2-2.5 hours, and then ultrasonicate for 30-40 minutes. Then, cool down to 30-35℃ naturally with the reactor and release the pressure to normal pressure. Filter to obtain filter residue and filtrate, and place the filter residue in a drying oven to dry at 60-70℃ to obtain copper-removed tellurium-arsenic anode mud.

3. The copper anode slime purification process according to claim 2, characterized in that: Step S3: vacuum induction deselenization of copper-arsenic-tellurium anode mud, including the following steps: S3.1: The copper-removed arsenic-tellurium anode slime obtained in step S1.2, 6-8 parts by weight of 98% concentrated sulfuric acid, and 2-3 parts by weight of hydrogen peroxide are mixed and stirred uniformly, and then heated in an oven at 100-120°C for 1-1.5 hours to obtain matured anode slime; S3.2: Place the matured anode mud in an electromagnetic induction heating tubular furnace, pump the pressure in the furnace to 40-60 kPa, introduce air and control the air flow rate to 200-220 L / h, then heat it to 380-400 ° C at a heating rate of 10-15 ° C / min, keep it warm and calcine it for 15-20 minutes, and absorb the gas discharged from the electromagnetic induction heating tubular furnace through 2-3 times of sodium sulfite solution. Take out the solid matter in the electromagnetic induction heating tubular furnace and cool it to room temperature to obtain deselenized anode mud.

4. The process for purifying copper anode slime according to claim 3, characterized in that: Step S4 is to capture the precious metals from the deselenized anode mud silicon, comprising the following steps: S4.1: Place the deselenized anode mud and the metal gel scavenger in a mass ratio of 1:(1-1.5) in a high-speed stirrer at a stirring speed of 800-1000 rpm and stir them evenly. Then place them in a tube furnace, introduce nitrogen for 3-5 minutes, seal the tube furnace, heat to 900-950°C at a heating rate of 8-10°C / min, hold the temperature for 6-8 hours, and then cool to 30-45°C to obtain a mixed metal material. S4.2: The mixed metal material is crushed in a crusher for 10-15 minutes with a particle size of 2-3 mm. The metal particles and slag are then sorted and separated to obtain bismuth-silver-gold alloy particles. The bismuth-silver-gold alloy particles are distilled at a pressure of 3-4 Pa and a temperature of 1000-1050°C for 2-2.5 hours to obtain gold-rich silver slag. The gold-rich silver slag is subjected to chlorination to obtain gold separation liquid and silver powder. The gold separation liquid is reduced with oxalic acid to obtain gold powder.

5. The process for purifying copper anode mud according to claim 2, characterized in that: In step S1.2, the volume ratio of the mixed gas of chlorine and oxygen introduced into the reactor is 1:(4-5).

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