A method for recovering silver, lead, zinc, iron from silver-containing jarosite residue

Abstract

The application discloses a method for recovering silver, lead, zinc and iron from silver-containing jarosite residue. The method uses silver-containing jarosite residue as raw material, and obtains jarosite residue roasting material by roasting the silver-containing jarosite residue at low temperature. The jarosite residue roasting material is leached by using high-purity water to obtain jarosite residue water leaching material and silver-containing leaching liquid. Silver is enriched in the form of silver chloride by adding chlorine to the silver-containing leaching liquid, and the silver-precipitated water leaching liquid is obtained. The jarosite residue water leaching material is leached by using acid to obtain acid leaching residue rich in lead sulfate and acid leaching liquid, the acid leaching liquid is mixed with the silver-precipitated water leaching liquid, and an oxidizing agent is added to oxidize Fe 2+ to Fe 3+ . Subsequently, the pH is adjusted by using an alkaline solution to obtain iron hydroxide or iron phosphate. The pH-adjusted liquid after solid-liquid separation is purified to obtain a zinc sulfate solution. The recovery rates of iron, silver and lead can reach more than 90%, and the recovery rate of zinc can reach more than 80%. The application prospect is good.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of hydrometallurgical comprehensive recovery, more particularly, to a method for recovering silver, lead, zinc and iron from silver-containing jarosite. BACKGROUND

[0002] Currently, the jarosite method is commonly used to remove iron in industrial zinc hydrometallurgy. The solid waste jarosite produced generally contains 25-30% iron, 0.2-0.8% copper, 0.5-10% lead, 5-12% zinc, and some rare and precious metals such as gallium, germanium, indium and silver. Silver mainly exists in the form of silver jarosite, which is formed by replacing iron atoms with silver atoms in the form of isomorphism during the iron removal process by the jarosite method, and most of the silver is wrapped by jarosite. With the rapid development of the new energy industry, the jarosite method is also applied to the recycling process of waste power batteries. Therefore, in order to meet the harmless treatment of the increasing output of jarosite, a new method needs to be developed for the resource utilization of jarosite. How to separate silver and other elements in silver-containing jarosite has attracted widespread attention.

[0003] Currently, the main way to treat jarosite is direct landfill, which not only harms the environment, but also wastes resources. Patent CN 105385858 B discloses a method for preparing iron red and recovering silver, which realizes the recovery of iron and silver in jarosite by combining hot acid leaching with thiourea leaching. The process is simple, but other valuable metal elements in the jarosite are not well recovered and utilized. Patent CN 109852803 B discloses a method for recovering valuable metals and iron from jarosite, which realizes the enrichment of valuable components such as iron, lead and silver by flotation of the slurry, but does not separate the valuable elements in the form of compounds. Patent CN 111069232 A discloses a method for washing and recovering zinc from zinc hydrometallurgy jarosite and harmless treatment of the recovered residue, which realizes the recovery of zinc by combining slurry and pressure filtration, but only reduces the landfill amount of a small amount of jarosite, and a large amount of valuable elements are not recovered and utilized. SUMMARY

[0004] The present application solves the above-mentioned problems existing in the prior art, and the purpose of the present application is to provide a method for recovering silver, lead, zinc and iron from silver-containing jarosite.

[0005] To achieve the above-mentioned purpose, the present application relies on the following specific technical means:

[0006] A method for recovering silver, lead, zinc and iron from silver-containing jarosite, comprising the following steps:

[0007] (1) low-temperature roasting of silver-containing jarosite followed by water leaching;

[0008] (2) After separating the water leaching residue from the water leaching solution, at least one of silver deposition from the water leaching solution by adding a substance containing chlorine, fluorine and bromine, and sulfuric acid, and silver deposition from the sulfuric acid;

[0009] (3) The water leaching residue is further subjected to acid leaching to obtain acid leaching residue rich in lead and acid leaching solution, and the acid leaching residue rich in lead is washed and filtered to be used as a lead smelting raw material;

[0010] (4) The mixed solution of the silver-deposited water leaching solution and the acid leaching solution is oxidized by using an oxidizing agent, and the pH is adjusted by using an alkaline solution to obtain iron hydroxide or iron phosphate according to product requirements;

[0011] (5) The pH-adjusted liquid after solid-liquid separation is purified to obtain a zinc-containing solution for zinc recovery.

[0012] In the method, the silver-containing jarosite residue is completely decomposed into sulfates by low-temperature roasting of the silver-containing jarosite residue in step (1), and silver is released; preferably, the roasting is carried out at 300-800℃ for at least 1h.

[0013] Preferably, the roasting in step (1) uses a muffle furnace, and the roasting atmosphere is air.

[0014] Preferably, the silver-containing jarosite residue roasting material in step (1) is crushed and ball milled, and then the ball-milled silver-containing jarosite residue roasting material is sieved to obtain silver-containing jarosite residue roasting powder.

[0015] Preferably, the ball milling uses a planetary ball mill, and the rotation speed of the planetary ball mill is 200-300r / min, and the ball milling time is 4-6h, and the particle size of the silver-containing jarosite residue roasting powder after ball milling is 200-300 mesh.

[0016] In the method, the liquid-solid ratio of water to the silver-containing jarosite residue used in step (1) is 2:1-7:1, preferably 3:1-6:1; during the water leaching process, the leaching temperature is 30-90℃, preferably 40-70℃; the leaching time is 1-8h, preferably 3-6h; the solution in the container is in a stirring state, and the stirring rotor rotation speed is 100-600r / min, more preferably 200-400r / min.

[0017] Preferably, after leaching in step (1), centrifugal separation is carried out, 2-6 50ml centrifuge tubes are used, the liquid in the container is poured into the tubes, and a centrifuge is used for separation, the centrifuge rotation speed is kept at 7000r / min, and the centrifugation time is 1-10min, more preferably 2-8min.

[0018] The method, step (2) adding chlorine silver chloride source to water immersion solution includes at least one of sodium chloride, hydrochloric acid, potassium chloride, preferably sodium chloride; The liquid-solid ratio of the water immersion solution used and the chlorine source is 20:1-50:1, preferably 20:1-30:1; The silver deposition temperature is 30-90 DEG C, preferably 60-80 DEG C; The silver deposition time is 5-20 min, preferably 10-15 min.

[0019] The method, step (3) the acid used includes at least one of hydrochloric acid and sulfuric acid, preferably sulfuric acid, the concentration of sulfuric acid is 7-16 mol / L, the liquid-solid ratio of sulfuric acid and silver-containing jarosite slag is 2:1-7:1, preferably 3:1-6:1; In the process of sulfuric acid leaching, the leaching temperature is 30-90 DEG C, preferably 50-90 DEG C; The leaching time is 1-8h, preferably 2-6h.

[0020] Further,

[0021] (1) The liquid-solid ratio of sulfuric acid leaching is preferably 3:1-4:1, and the leaching time is preferably 2-4h, which can improve the leaching rate of zinc and iron in the solution, thereby increasing the recovery rate of zinc and iron;

[0022] (2) The sulfuric acid leaching concentration is preferably 50-80%, and the sulfuric acid leaching temperature is 50-80 DEG C, which can reduce the dissolution of lead sulfate in the solution, thereby increasing the recovery rate of lead.

[0023] Preferably, after step (3) acid leaching, centrifugal separation is carried out, 2-6 50ml centrifugal tubes are used, the liquid in the container is poured into the tube, and the centrifuge is used for separation, the centrifuge speed is kept at 7000r / min, and the centrifugation time is 1-10 min, and further preferably 2-8 min.

[0024] The method, step (4) the oxidant added needs to oxidize Fe 2+ To Fe 3+ ; The oxidant includes at least one of hydrogen peroxide, sodium chlorate and chlorine, preferably sodium chlorate; The liquid-solid ratio of the solution used and the oxidant is 20:1-100:1, preferably 20:1-50:1; The oxidation temperature is 50-90 DEG C, preferably 60-80 DEG C; The oxidation time is 1-10 min, preferably 3-7 min.

[0025] Preferably, in the process of oxidizing the mixed solution of water immersion solution and acid immersion solution by the oxidant, the solution in the container is in a stirring state, and the stirring rotor speed is 100-600r / min, and further preferably 200-400r / min.

[0026] The method, in step (4), the pH of the solution is adjusted to 2-5, preferably the pH is adjusted to 3-4, to obtain the iron hydroxide product; the pH of the solution is adjusted to 1-3, preferably the pH is adjusted to 1.5-2, to obtain the iron phosphate product; the alkaline solution used is at least one of ammonia, sodium carbonate and sodium hydroxide, preferably sodium hydroxide solution, the concentration of NaOH solution is 1-10 mol / L.

[0027] In step (4), the pH is adjusted after adding sodium phosphate to obtain sodium phosphate.

[0028] The final product of iron can be diversified, and the product iron phosphate can be obtained by adding sodium phosphate during the pH adjustment operation, and the product iron hydroxide can be obtained without adding sodium phosphate. Preferably, the solution is stirred at room temperature, the stirring rotor speed is 100-600 r / min, and the initial pH value should be negative; the NaOH solution is slowly added into the container.

[0029] After the pH adjustment reaction is completed, the centrifugal separation process is carried out, 2-6 50 ml centrifuge tubes are used, the liquid in the container is poured into the tubes, and a centrifuge is used for separation, the centrifuge speed is kept at 7000 r / min, and the centrifugal time is 1-10 min, and more preferably 2-8 min.

[0030] In step (5) of the method, the purifying agent used for purifying the liquid after pH adjustment is at least one of activated carbon and zinc powder, preferably zinc powder, the liquid-solid ratio of zinc powder to liquid is 1:1-4:1, preferably 2:1-3:1, the purification temperature is 50-80°C, preferably 50-70°C, and the purification time is 10-60 min, preferably 30-50 min.

[0031] The purified liquid is finally centrifuged: 2-6 50 ml centrifuge tubes are used, the liquid in the container is poured into the tubes, and a centrifuge is used for separation, the centrifuge speed is kept at 7000 r / min, and the centrifugal time is 1-10 min, and more preferably 2-8 min.

[0032] Compared with the prior art, the beneficial effects of the present application are:

[0033] The application provides a method for recovering silver, lead, zinc and iron from silver-containing jarosite slag.

[0034] The application provides a method for recovering silver, lead, zinc and iron from silver-containing jarosite slag. BRIEF DESCRIPTION OF DRAWINGS

[0035] Figure 1 A process flow diagram of the method for recovering silver, lead, zinc and iron from silver-containing jarosite slag;

[0036] Figure 2 A XRD distribution diagram of the silver-containing jarosite slag;

[0037] Figure 3 A XRD distribution diagram of the silver-containing jarosite slag after low-temperature roasting;

[0038] Figure 4 A XRD distribution diagram of the acid leaching residue of the silver-containing jarosite slag. DETAILED DESCRIPTION

[0039] The application will be further described below in combination with the accompanying drawings and specific examples, but the examples do not limit the application in any form. Unless otherwise specified, the reagents, methods and equipment used in the application are conventional reagents, methods and equipment in the technical field.

[0040] Unless otherwise specified, the reagents and materials used in the following examples are commercially available.

[0041] Example 1

[0042] A method for recovering silver, lead, zinc and iron from silver-containing jarosite slag, comprising the following steps:

[0043] Step one: put the silver-containing jarosite slag produced by the iron removal process of Indian Zinc Co. Ltd. into a muffle furnace for roasting at 500℃, the roasting atmosphere is air, and the roasting time is 2h, to obtain silver-containing jarosite slag roasting material.

[0044] The composition of the silver-containing jarosite slag is shown in Table 1:

[0045] Table 1

[0046]

[0047] Step two: put the silver-containing jarosite slag roasting material into a ball mill tank, and grind it by a planetary ball mill at a speed of 250r / min for 6h, and then pass it through a 200 mesh screen to obtain silver-containing jarosite slag roasting powder;

[0048] The composition of the silver-containing jarosite slag roasting material is shown in Table 2:

[0049] Table 2

[0050]

[0051]

[0052] Step three: take 50g of silver-containing jarosite slag roasting powder and add it to a conical flask, add 350mL of high-purity water with a liquid-solid ratio of 7:1; put the conical flask into an oil bath stirring pot for high-purity water leaching for 6h, the leaching temperature is 30℃, and the stirring rotor speed is 200r / min;

[0053] Step four: after the reaction process is completed, centrifuge the solution, use 6 50ml centrifuge tubes, pour the liquid in the container into the tubes, use a centrifuge to separate, the centrifuge speed is kept at 7000r / min, and the centrifugation time is 2min, and then dry at 60℃ for 12h to obtain water leaching solution and water leaching residue;

[0054] Step five: use sodium chloride to precipitate silver from the water leaching solution, the amount of sodium chloride is 2 times the theoretical amount, and silver chloride powder is obtained as the product;

[0055] The composition of the water leaching residue is shown in Table 3:

[0056] Table 3

[0057]

[0058] Step six: take the water leaching residue and add it to a conical flask, add 80% sulfuric acid with a liquid-solid ratio of 3:1; put the conical flask into an oil bath stirring pot for sulfuric acid leaching for 2h, the leaching temperature is 80℃, and the stirring rotor speed is 200r / min;

[0059] Step seven: after the reaction process is completed, the solution is centrifuged, 6 50ml centrifuge tubes are used, the liquid in the container is poured into the tubes, the centrifuge is used for separation, the centrifuge speed is kept at 7000r / min, the centrifugation time is 2min, and then the solution is washed with water and ethanol for 3 times respectively, and dried at 60℃ for 12h to obtain the sulfuric acid leaching solution and the lead sulfate-rich leaching residue product;

[0060] The composition of the sulfuric acid leaching residue is shown in Table 4;

[0061] Table 4

[0062]

[0063]

[0064] Step eight: 6g NaClO3 is added to the mixed solution of the water leaching solution and the sulfuric acid leaching solution after silver deposition, the stirring rotor is kept rotating at 200r / min during the addition of NaClO3, the oil bath pot temperature is stabilized at 60℃, and the oxidation time is 5min;

[0065] Step nine: 8g of sodium phosphate is added to the oxidized solution, and the stirring rotor is kept rotating at 200r / min during the addition of sodium phosphate;

[0066] Step ten: the glass electrode of the calibrated pH meter is placed in the conical flask, the stirring rotor is stirred at 200r / min at room temperature, then 10mol / L NaOH solution is slowly added to the conical flask through a dropper, after the addition is completed, the pH meter shows that the pH is adjusted to 1.5, and the pH meter reading does not change after 15min, that is, the pH adjustment step is completed;

[0067] Step eleven: the pH adjustment product is centrifuged, 6 50ml centrifuge tubes are used, the liquid in the container is poured into the tubes, the centrifuge speed is kept at 7000r / min, the centrifugation time is 2min, and the centrifuge is used for separation to obtain the pH adjustment residue and the pH adjusted liquid;

[0068] Step twelve: the pH adjustment residue is dried at 60℃ for 12h to obtain the product iron phosphate;

[0069] Step thirteen: zinc powder is added to the pH adjusted liquid for purification, the liquid-solid ratio of the added zinc powder to the pH adjusted liquid is 3:1, the purification temperature is 50℃, and the purification time is 20min;

[0070] Step Four: Centrifugal separation was performed on the purified product, 6 50ml centrifuge tubes were used, the liquid in the container was poured into the tubes, the centrifuge speed was kept at 7000r / min, the centrifugal time was 2min, the centrifuge was used for separation, and the purified residue and the product pure zinc sulfate solution were obtained.

[0071] To verify the separation effect of the method, the recovery rates of Ag, Pb, Zn and Fe were further calculated by material balance, which was consistent with the element content results in the silver-containing jarosite residue, the material conservation, and the following conclusions were obtained:

[0072] (1) Ag will enter the water leaching solution, the Ag content in the water leaching solution accounts for more than 92% of the Ag content in the silver-containing jarosite residue;

[0073] (2) The content of Pb in the sulfuric acid leaching residue is 90% of the total content of Pb in the silver-containing jarosite residue;

[0074] (3) Fe will enter the pH adjustment residue, the Fe content in the pH adjustment residue accounts for more than 93% of the Fe content in the silver-containing jarosite residue.

[0075] (4) Zn will enter the pH adjusted solution, the Zn content in the pH adjusted solution accounts for more than 85% of the Zn content in the silver-containing jarosite residue.

[0076] Example 2

[0077] A method for recovering silver, lead, zinc and iron from silver-containing jarosite residue, comprising the following steps:

[0078] Step one: Put the silver-containing jarosite residue (composition see Table 1) into a muffle furnace and roast at 500℃, the roasting atmosphere is air, the roasting time is 2h, and the silver-containing jarosite residue is obtained.

[0079] Step two: Put the silver-containing jarosite residue into a ball mill jar, and grind it in a planetary ball mill at a speed of 250r / min for 6h, and then pass it through a 200 mesh sieve to obtain a silver-containing jarosite residue powder;

[0080] Step three: Take 50g of silver-containing jarosite residue powder and add it to a conical flask, add 350mL of high-purity water with a liquid-solid ratio of 7:1; Put the conical flask into an oil bath stirring pot and leach for 6h, the leaching temperature is 30℃, and the stirring rotor speed is 200r / min;

[0081] Step four: After the reaction is completed, centrifugal separation is performed on the solution, 6 50ml centrifuge tubes are used, the liquid in the container is poured into the tubes, the centrifuge is used for separation, the centrifuge speed is kept at 7000r / min, the centrifugal time is 2min, and the water leaching residue is obtained after drying at 60℃ for 12h.

[0082] Step five: the water immersion liquid is silvered with sodium chloride, the amount of sodium chloride is 2 times of the theoretical amount, and the product silver chloride powder is obtained;

[0083] Step six: the water immersion residue is taken into a conical flask, 80% sulfuric acid is added with a liquid-solid ratio of sulfuric acid to water immersion residue being 3:1; the conical flask is placed in an oil bath stirring pot for sulfuric acid leaching for 2h, the leaching temperature is 50°C, and the stirring rotor rotates at a speed of 200r / min;

[0084] Step seven: after the reaction process is completed, the solution is centrifuged, 6 50ml centrifuge tubes are used, the liquid in the container is poured into the tubes, the centrifuge is used for separation, the centrifuge speed is kept at 7000r / min, the centrifugation time is 2min, and then the solution is washed with water and ethanol for 3 times respectively, and dried at 60°C for 12h, to obtain the sulfuric acid leaching liquid and the product of lead sulfate-rich leaching residue;

[0085] Step eight: 6g NaClO3 is added to the mixed solution of the water leaching liquid and the sulfuric acid leaching liquid after silvering, the stirring rotor is kept rotating at a speed of 200r / min during the addition of NaClO3, the oil bath pot temperature is stabilized at 60°C, and the oxidation time is 5min;

[0086] Step nine: 8g sodium phosphate is added to the oxidized solution, and the stirring rotor is kept rotating at a speed of 200r / min during the addition of sodium phosphate;

[0087] Step ten: the glass electrode of the calibrated pH meter is placed in the conical flask, the stirring rotor is stirred at a speed of 200r / min at room temperature, then 10mol / L NaOH solution is slowly added to the conical flask through a dropper, after the addition is completed, the pH meter shows that the pH is adjusted to 1.5, and the pH meter reading does not change after 15min, that is, the pH adjustment step is completed;

[0088] Step eleven: the pH adjustment product is centrifuged, 6 50ml centrifuge tubes are used, the liquid in the container is poured into the tubes, the centrifuge speed is kept at 7000r / min, the centrifugation time is 2min, and the centrifuge is used for separation, to obtain the pH adjustment residue and the pH adjusted liquid;

[0089] Step twelve: the pH adjustment residue is dried at a temperature of 60°C for 12h, to obtain the product iron phosphate;

[0090] Step thirteen: zinc powder is added to the pH adjusted liquid for purification, the liquid-solid ratio of the added zinc powder to the pH adjusted liquid is 3:1, and the purification temperature is 50°C; the purification time is 20min;

[0091] Step Four: The purified product was centrifuged, 6 50ml centrifuge tubes were used, the liquid in the container was poured into the tube, the centrifuge speed was kept at 7000r / min, the centrifugation time was 2min, the centrifuge was used for separation, and the purified residue and the product pure zinc sulfate solution were obtained.

[0092] In order to verify the separation effect of the method, the recovery rates of Ag, Pb, Zn and Fe were calculated by material balance, and the following conclusions were obtained:

[0093] Ag will enter the water leaching solution, and the Ag content in the water leaching solution accounts for more than 92% of the Ag content in the silver-containing jarosite residue;

[0094] Pb will enter the sulfuric acid leaching residue, and the Pb content in the sulfuric acid leaching residue accounts for more than 92% of the Pb content in the silver-containing jarosite residue;

[0095] Zn will enter the pH adjusted liquid, and the Zn content in the pH adjusted liquid accounts for more than 82% of the Zn content in the silver-containing jarosite residue;

[0096] Fe will enter the pH adjustment residue, and the Fe content in the pH adjustment residue accounts for more than 91% of the Fe content in the silver-containing jarosite residue.

[0097] Example 3

[0098] A method for recovering silver, lead, zinc and iron from silver-containing jarosite residue, comprising the following steps:

[0099] Step one: Put the silver-containing jarosite residue (composition see Table 1) into a muffle furnace and calcine at 500℃, the calcination atmosphere is air, the calcination time is 2h, and the silver-containing jarosite residue is obtained.

[0100] Step two: Put the silver-containing jarosite residue into a ball mill tank, and grind it by a planetary ball mill at a speed of 250r / min for 6h, and then pass it through a 200 mesh sieve to obtain a silver-containing jarosite residue powder;

[0101] Step three: Take 50g of silver-containing jarosite residue powder and add it to a conical flask, add 350mL of high-purity water with a liquid-solid ratio of 7:1; Put the conical flask into an oil bath stirring pot and leach for 6h, the leaching temperature is 30℃, and the stirring rotor rotates at a speed of 200r / min;

[0102] Step four: After the reaction is completed, the solution is centrifuged, 6 50ml centrifuge tubes are used, the liquid in the container is poured into the tube, the centrifuge is used for separation, the centrifuge speed is kept at 7000r / min, the centrifugation time is 2min, and the water leaching residue is obtained after drying at 60℃ for 12h;

[0103] Step five: silver chloride is precipitated from the water leaching solution by adding sodium chloride, the amount of sodium chloride is 2 times of the theoretical amount, and silver chloride powder is obtained as the product;

[0104] Step six: the water leaching residue is taken into a conical flask, 50% sulfuric acid is added at a liquid-solid ratio of sulfuric acid to water leaching residue of 4:1, the conical flask is placed in an oil bath stirring pot for sulfuric acid leaching for 4h, the leaching temperature is 70°C, and the stirring rotor rotates at a speed of 200r / min;

[0105] Step seven: after the reaction process is completed, the solution is centrifuged, 6 50ml centrifuge tubes are used, the liquid in the container is poured into the tubes, the centrifuge is used for separation, the centrifuge speed is kept at 7000r / min, the centrifugation time is 2min, and then the solution is washed with water and ethanol for 3 times respectively, and dried at 60°C for 12h to obtain the sulfuric acid leaching solution and the product of lead sulfate-rich leaching residue;

[0106] Step eight: 6g NaClO3 is added to the mixed solution of the water leaching solution and the sulfuric acid leaching solution after silver chloride precipitation, the stirring rotor is kept rotating at a speed of 200r / min during the addition of NaClO3, the oil bath pot temperature is stabilized at 60°C, and the oxidation time is 5min;

[0107] Step nine: the glass electrode of the calibrated pH meter is placed in the conical flask, the stirring rotor rotates at a speed of 200r / min at room temperature, then 10mol / L NaOH solution is slowly added to the conical flask through a dropper, after the addition is completed, the pH meter shows that the pH is adjusted to 3.5, and the pH meter reading does not change after 15min, that is, the pH adjustment step is completed;

[0108] Step ten: the pH adjustment product is centrifuged, 6 50ml centrifuge tubes are used, the liquid in the container is poured into the tubes, the centrifuge speed is kept at 7000r / min, the centrifugation time is 2min, and the centrifuge is used for separation to obtain the pH adjustment residue and the pH adjusted solution, and the pH adjustment residue is dried at 60°C;

[0109] Step eleven: the pH adjustment residue is calcined at a temperature of 500°C for 0.5h to obtain the product iron red;

[0110] Step twelve: zinc powder is added to the pH adjusted solution for purification, the liquid-solid ratio of the added zinc powder to the pH adjusted solution is 3:1, and the purification temperature is 50°C; the purification time is 20min;

[0111] Step thirteen: the purified product is centrifuged, 6 50ml centrifuge tubes are used, the liquid in the container is poured into the tubes, the centrifuge speed is kept at 7000r / min, the centrifugation time is 2min, and the centrifuge is used for separation to obtain the purified residue and the product of pure zinc sulfate solution.

[0112] In order to verify the separation effect of the method, the recovery rates of Ag, Pb, Zn and Fe are calculated by material balance, and the following conclusions are obtained:

[0113] Ag will enter the water leaching solution, and the Ag content in the water leaching solution accounts for more than 92% of the Ag content in the silver-containing jarosite slag;

[0114] Pb will enter the sulfuric acid leaching residue, and the Pb content in the sulfuric acid leaching residue accounts for more than 90% of the Pb content in the silver-containing jarosite slag;

[0115] Zn will enter the pH-adjusted solution, and the Zn content in the pH-adjusted solution accounts for more than 84% of the Zn content in the silver-containing jarosite slag;

[0116] Fe will enter the pH-adjusted residue, and the Fe content in the pH-adjusted residue accounts for more than 95% of the Fe content in the silver-containing jarosite slag.

[0117] Example 4

[0118] A method for recovering silver, lead, zinc and iron from silver-containing jarosite slag, comprising the following steps:

[0119] Step one: Put the silver-containing jarosite slag (composition see Table 1) into a muffle furnace and roast at 500℃, the roasting atmosphere is air, and the roasting time is 2h, to obtain silver-containing jarosite slag roasting material.

[0120] Step two: Put the silver-containing jarosite slag roasting material into a ball mill jar, and grind it with a planetary ball mill at a speed of 250r / min for 6h, and then pass it through a 200 mesh sieve to obtain silver-containing jarosite slag roasting powder;

[0121] Step three: Take 50g of silver-containing jarosite slag roasting powder and add it to a conical flask, add 350mL of high-purity water with a liquid-solid ratio of 7:1; Put the conical flask into an oil bath stirring pot and carry out high-purity water leaching for 6h, the leaching temperature is 30℃, and the stirring rotor rotates at a speed of 200r / min;

[0122] Step four: After the reaction is completed, centrifuge the solution, use 6 50ml centrifuge tubes, pour the liquid in the container into the tubes, use a centrifuge to separate, the centrifuge speed is kept at 7000r / min, and the centrifugation time is 2min, and then dry at 60℃ for 12h to obtain the water leaching solution and water leaching residue;

[0123] Step five: Silver is precipitated from the water leaching solution with sodium chloride, and the amount of sodium chloride used is 2 times the theoretical amount, to obtain silver chloride powder as the product;

[0124] Step six: take the water leaching residue and add it to the conical flask, add 50% sulfuric acid with a liquid-solid ratio of sulfuric acid: water leaching residue of 4:1; put the conical flask into the oil bath stirring pot for sulfuric acid leaching for 2h, the leaching temperature is 70℃, the stirring rotor rotates at 200r / min;

[0125] Step seven: after the reaction process is completed, centrifuge the solution, use 6 50ml centrifuge tubes, pour the liquid in the container into the tubes, use the centrifuge to separate, the centrifuge speed is kept at 7000r / min, the centrifugation time is 2min, wash with water and ethanol for 3 times respectively, dry at 60℃ for 12h, to obtain the sulfuric acid leaching solution and the product of lead sulfate-rich leaching residue;

[0126] Step eight: add 6g NaClO3 to the mixed solution of water leaching solution and sulfuric acid leaching solution after silver deposition, ensure that the stirring rotor rotates at 200r / min during the addition of NaClO3, the oil bath pot temperature is stabilized at 60℃, and the oxidation time is 5min;

[0127] Step nine: put the calibrated pH meter glass electrode into the conical flask, stir the stirring rotor at room temperature at 200r / min, then slowly add 10mol / L NaOH solution to the conical flask through the dropper, after the addition is completed, the pH meter shows that the pH is adjusted to 3.5, and the pH meter reading does not change after 15min, that is, the pH adjustment step is completed;

[0128] Step ten: centrifuge the pH adjustment product, use 6 50ml centrifuge tubes, pour the liquid in the container into the tubes, the centrifuge speed is kept at 7000r / min, the centrifugation time is 2min, use the centrifuge to separate, to obtain the pH adjustment residue and the pH adjusted liquid, the pH adjustment residue is dried at 60℃;

[0129] Step eleven: calcine the pH adjustment residue at a temperature of 500℃ for 0.5h to obtain the product iron red;

[0130] Step twelve: add zinc powder to the pH adjusted liquid for purification, the liquid-solid ratio of the added zinc powder to the pH adjusted liquid is 3:1, the purification temperature is 50℃; the purification time is 20min;

[0131] Step thirteen: centrifuge the purification product, use 6 50ml centrifuge tubes, pour the liquid in the container into the tubes, the centrifuge speed is kept at 7000r / min, the centrifugation time is 2min, use the centrifuge to separate, to obtain the purification residue and the product of pure zinc sulfate solution.

[0132] In order to verify the separation effect of the method, the recovery rates of Ag, Pb, Zn and Fe are calculated by material balance calculation, and the following conclusions are obtained:

[0133] Ag will enter the water leaching solution, and the Ag content in the water leaching solution accounts for more than 92% of the Ag content in the silver-containing jarosite residue;

[0134] Pb will enter the sulfuric acid leaching residue, and the Pb content in the sulfuric acid leaching residue accounts for more than 91% of the Pb content in the silver-containing jarosite residue;

[0135] Zn will enter the pH-adjusted solution, and the Zn content in the pH-adjusted solution accounts for more than 81% of the Zn content in the silver-containing jarosite residue;

[0136] Fe will enter the pH-adjusted residue, and the Fe content in the pH-adjusted residue accounts for more than 92% of the Fe content in the silver-containing jarosite residue.

[0137] Comparative Example 1

[0138] A method for recovering silver, lead, zinc and iron from a silver-containing jarosite residue, comprising the following steps:

[0139] Step one: Put the silver-containing jarosite residue (composition see Table 1) into a muffle furnace for roasting at 500℃, the roasting atmosphere is air, and the roasting time is 2h, to obtain a silver-containing jarosite residue roasting material.

[0140] Step two: Put the silver-containing jarosite residue roasting material into a ball mill jar, and grind it by a planetary ball mill at a speed of 250r / min for 6h, and then pass it through a 200 mesh sieve to obtain a silver-containing jarosite residue roasting powder;

[0141] Step three: Take 50g of the silver-containing jarosite residue roasting powder and add it to a conical flask, add 350mL of high-purity water with a liquid-solid ratio of 7:1; Put the conical flask into an oil bath stirring pot for high-purity water leaching for 6h, the leaching temperature is 30℃, and the stirring rotor rotates at a speed of 200r / min;

[0142] Step four: After the reaction is completed, centrifuge the solution, use 6 50ml centrifuge tubes, pour the liquid in the container into the tubes, use a centrifuge to separate, the centrifuge speed is kept at 7000r / min, and the centrifugation time is 2min, and then dry at 60℃ for 12h to obtain a water leaching solution and a water leaching residue;

[0143] Step five: Silver is precipitated from the water leaching solution by sodium chloride, and the amount of sodium chloride is 2 times the theoretical amount, to obtain a silver chloride product powder;

[0144] Step six: Take the water leaching residue and add it to a conical flask, add 40% sulfuric acid with a liquid-solid ratio of 4:1; Put the conical flask into an oil bath stirring pot for sulfuric acid leaching for 2h, the leaching temperature is 30℃, and the stirring rotor rotates at a speed of 200r / min;

[0145] Step seven: after the reaction process is completed, the solution is centrifuged, 6 50ml centrifuge tubes are used, the liquid in the container is poured into the tube, the centrifuge is used for separation, the centrifuge speed is kept at 7000r / min, the centrifugation time is 2min, and then the water and ethanol are washed for 3 times respectively, and the product of sulfuric acid leaching solution and lead sulfate-rich leaching residue is obtained after drying at 60℃ for 12h;

[0146] Step eight: 6g NaClO3 is added to the mixed solution of water leaching solution and sulfuric acid leaching solution after silver deposition, the stirring rotor is kept rotating at 200r / min during the addition of NaClO3, the oil bath pot temperature is stabilized at 60℃, and the oxidation time is 5min;

[0147] Step nine: the glass electrode of the calibrated pH meter is put into the conical flask, the stirring rotor is stirred at room temperature at a speed of 200r / min, then 10mol / L NaOH solution is slowly added to the conical flask through a dropper, after the addition is completed, the pH meter shows that the pH is adjusted to 3.5, and the pH meter reading does not change after 15min, that is, the pH adjustment step is completed;

[0148] Step ten: the pH adjustment product is centrifuged, 6 50ml centrifuge tubes are used, the liquid in the container is poured into the tube, the centrifuge speed is kept at 7000r / min, the centrifugation time is 2min, and the centrifuge is used for separation, to obtain the pH adjustment residue and the pH adjusted liquid, and the pH adjustment residue is dried at 60℃;

[0149] Step eleven: the pH adjustment residue is calcined at a temperature of 500℃ for 0.5h to obtain the product iron red;

[0150] Step twelve: zinc powder is added to the pH adjusted liquid for purification, the liquid-solid ratio of the added zinc powder to the pH adjusted liquid is 3:1, the purification temperature is 50℃, and the purification time is 20min;

[0151] Step thirteen: the purified product is centrifuged, 6 50ml centrifuge tubes are used, the liquid in the container is poured into the tube, the centrifuge speed is kept at 7000r / min, the centrifugation time is 2min, and the centrifuge is used for separation, to obtain the purified residue and the product of pure zinc sulfate solution.

[0152] In order to verify the separation effect of the method, the recovery rates of Ag, Pb, Zn and Fe are calculated by material balance calculation, and the following conclusions are obtained:

[0153] Ag will enter the water leaching solution, and the Ag content in the water leaching solution accounts for more than 92% of the Ag content in the silver-containing jarosite residue;

[0154] Pb will enter the sulfuric acid leaching residue, and the Pb content in the sulfuric acid leaching residue accounts for more than 94% of the Pb content in the silver-containing jarosite residue;

[0155] Zn will enter the pH-adjusted liquid, and the content of Zn in the pH-adjusted liquid accounts for more than 65% of the content of Zn in the silver-containing jarosite slag;

[0156] Fe will enter the pH-adjusted slag, and the content of Fe in the pH-adjusted slag accounts for more than 81% of the content of Fe in the silver-containing jarosite slag.

Claims

1. A process for the recovery of silver, lead, zinc, iron from silver bearing jarosite residue, characterized in that, The method comprises the following steps: (1) low-temperature roasting silver-containing jarosite and then water leaching; (2) separating the water leaching residue from the water leaching solution, adding at least one of a substance containing chlorine, fluorine and bromine and sulfuric acid into the water leaching solution to realize silver precipitation; (3) acid leaching the water leaching residue to obtain lead-rich acid leaching residue and acid leaching solution, and washing and filtering the lead-rich acid leaching residue to be used as a lead smelting raw material; (4) using an oxidizing agent to oxidize the mixed solution of the water leaching solution and the acid leaching solution after silver precipitation, and then using an alkaline solution to adjust the pH value, and obtaining iron hydroxide or iron phosphate according to product requirements; (5) obtaining a zinc-containing solution by purifying the pH-adjusted liquid after solid-liquid separation, which is used for zinc recovery.

2. The method of claim 1, wherein, In step (1), the silver-containing jarosite is roasted at 300-800 ℃ for at least 1 h, so that the jarosite, potassium jarosite and lead jarosite in the silver-containing jarosite are completely roasted and decomposed into sulfates, and silver is released.

3. The method of claim 1, wherein, In step (1), the liquid-solid ratio of water to the silver-containing jarosite is 2:1-7:1; during the water leaching process, the leaching temperature is 30-90 ℃, and the leaching time is 1-8 h.

4. The method of claim 1, wherein, In step (2), the chlorine source for silver precipitation added into the water leaching solution includes at least one of sodium chloride, hydrochloric acid and potassium chloride; the silver precipitation temperature is 30-90 ℃; and the silver precipitation time is 5-20 min.

5. The method according to claim 1, characterized in that, In step (3), the acid used includes at least one of hydrochloric acid and sulfuric acid; when sulfuric acid is used, the sulfuric acid concentration is 50%-80%, and the liquid-solid ratio of sulfuric acid to the water leaching residue is 2:1-7:1; during the sulfuric acid leaching process, the leaching temperature is 30-90 ℃, and the leaching time is 1-8 h.

6. The method of claim 1, wherein, The oxidant added in step (4) needs to oxidize Fe 2+ to Fe 3+ ; the oxidant includes at least one of hydrogen peroxide, sodium chlorate and chlorine; the oxidation temperature is 50-90℃; and the oxidation time is 1-10 min.

7. The method of claim 1, wherein, In step (4), the pH value of the solution is adjusted to 1-5; the alkaline solution used includes at least one of ammonia water, sodium carbonate and sodium hydroxide; when sodium hydroxide solution is used, the sodium hydroxide solution concentration is 1-10 mol / L.

8. The method of claim 1, wherein, In step (4), the pH value is adjusted to obtain iron phosphate after adding sodium phosphate.

9. The method of claim 1, wherein, In step (5), the purifying agent used for purifying the pH-adjusted liquid is at least one of activated carbon and zinc powder; when zinc powder is used, the liquid-solid ratio of zinc powder to the pH-adjusted liquid is 1:1-4:1, the purifying temperature is 50-80 ℃, and the purifying time is 10-60 min.

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