CN110396608B - Oxygen pressure leaching method for bismuth sulfide concentrate in methanesulfonic acid system - Google Patents
Oxygen pressure leaching method for bismuth sulfide concentrate in methanesulfonic acid system Download PDFInfo
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- CN110396608B CN110396608B CN201910710246.0A CN201910710246A CN110396608B CN 110396608 B CN110396608 B CN 110396608B CN 201910710246 A CN201910710246 A CN 201910710246A CN 110396608 B CN110396608 B CN 110396608B
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- methanesulfonic acid
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- sulfide concentrate
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- bismuth sulfide
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B3/00—Extraction of metal compounds from ores or concentrates by wet processes
- C22B3/04—Extraction of metal compounds from ores or concentrates by wet processes by leaching
- C22B3/16—Extraction of metal compounds from ores or concentrates by wet processes by leaching in organic solutions
- C22B3/1608—Leaching with acyclic or carbocyclic agents
- C22B3/1616—Leaching with acyclic or carbocyclic agents of a single type
- C22B3/165—Leaching with acyclic or carbocyclic agents of a single type with organic acids
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B30/00—Obtaining antimony, arsenic or bismuth
- C22B30/06—Obtaining bismuth
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
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Abstract
The invention discloses an oxygen pressure leaching method of a methanesulfonic acid system bismuth sulfide concentrate, which comprises the following steps: s1, pretreatment of materials: adding the bismuth sulfide concentrate into a vertical mill, finely grinding the bismuth sulfide concentrate by using the vertical mill, and drying the screened material for later use; s2, preparing liquid: according to the iron-containing phase and the iron content in the material, adding iron powder into the methanesulfonic acid solution, and then stirring the solution to fully mix the iron powder and the methanesulfonic acid solution to obtain the iron-containing methanesulfonic acid leaching agent. The method for leaching bismuth sulfide concentrate has the advantages that the leaching rate of bismuth is high and can reach more than 93%, the process flow is simple, the method is simple to operate, bismuth can be efficiently dissolved out, a sulfur product is obtained, and SO is not generated2And has the advantage of environmental protection.
Description
Technical Field
The invention relates to the related technical field of hydrometallurgy of color metals, in particular to an oxygen pressure leaching method of bismuth sulfide concentrate in a methanesulfonic acid system.
Background
The bismuth smelting process is divided into a fire method and a wet method. The pyrogenic smelting of bismuth is suitable for raw materials with high bismuth content, and the specific process comprises liquation smelting, precipitation smelting, reduction smelting, mixed smelting and low-temperature alkaline smelting. For example, chinese patent CN103305707A discloses a smelting method of bismuth concentrate; metal oxide as sulfur-fixing agent, sodium carbonate as reaction solvent and carbon as reducing agent, smelting at 750-950 deg.c,obtaining crude bismuth; the method can efficiently obtain crude bismuth, has simple equipment and short production period, and also has low-concentration SO2Smoke pollution, difficult effective recovery of valuable metals such as tungsten, molybdenum and the like, low automation level of equipment and the like.
The wet bismuth smelting process is suitable for bismuth-containing materials with low grade and complex components, and typically comprises ferric trichloride leaching, chlorine selective leaching, hydrochloric acid-nitrous acid leaching, chlorination hydrolysis, ore pulp electrolysis and the like, wherein FeCl is mainly adopted in the methods3Chlorine or nitric acid, etc. as oxidant and complexing agent to make S be leached out2-Converted into elemental sulfur, so that bismuth enters the leaching solution in the form of ions. Chinese patent CN1415785 puts bismuth sulfide ore into anode area with diaphragm, and leaches bismuth sulfide with chlorine produced by anode, so that bismuth enters electrolyte in ionic state, and bismuth ions are separated out on cathode through diaphragm to obtain metal bismuth powder. The chlorine gas easily produced by the anode of the method is easy to escape, the operation environment is deteriorated, and the iron is enriched in the solution and is difficult to treat. Chinese patent CN101775619A NaClO3The bismuth sulfide is used as an oxidant, the bismuth sulfide is leached out under normal pressure in a hydrochloric acid system, and after evolution and impurity removal, bismuth is recovered and the oxidant is regenerated through diaphragm electrolysis. The method has long flow, associated elements are leached in a large amount, the purification and impurity removal difficulty is high, and a large amount of alkali is consumed in the diaphragm electrodeposition process.
The oxygen pressure leaching process is used as one of the metallurgical strengthening processes, is used for treating nickel concentrate and copper concentrate at first and is popularized to the process for treating zinc sulfide concentrate later; the sulfide ore oxygen pressure leaching process is completed by combining two processes of sulfide roasting and calcine leaching into one process, so that sulfur in raw materials is leached in the form of elemental sulfur in the leaching process, and ions enter a leaching solution. Chinese patents CN109554539A and CN109554540A are respectively adopted by H2SO4And ammonia water are used as leaching media, bismuth is leached out under high temperature and high pressure in a pressurizing way, and crude bismuth is obtained by reduction smelting through a fire method or wet method HCl is leached out under normal pressure to prepare bismuth oxychloride or bismuth oxide; the process is complicated, the energy consumption is large by adopting subsequent reduction smelting, and HCl has strong corrosivity to equipment and is inconvenient to use.
Aiming at the problems that the existing bismuth smelting process by a fire method and a wet method cannot meet the increasingly severe national environmental protection requirement and certain process defects exist, the invention provides a methane sulfonic acid system bismuth sulfide concentrate oxygen pressure leaching process.
Disclosure of Invention
The invention aims to provide an oxygen pressure leaching method of bismuth sulfide concentrate in a methanesulfonic acid system, and aims to solve the problems of low bismuth leaching rate, complex operation process, high pollution, high corrosion to equipment and high cost in the existing bismuth smelting process mentioned in the background art.
In order to achieve the purpose, the invention provides the following technical scheme: an oxygen pressure leaching method of a methanesulfonic acid system bismuth sulfide concentrate comprises the following steps:
s1, pretreatment of materials: adding the bismuth sulfide concentrate into a vertical mill, finely grinding the bismuth sulfide concentrate by using the vertical mill, and drying the screened material for later use;
s2, preparing liquid: adding iron powder into a methanesulfonic acid solution properly according to an iron-containing phase and iron content in the material, and then stirring the solution to fully mix the iron powder and the methanesulfonic acid solution to obtain an iron-containing methanesulfonic acid leaching agent;
s3, mixing: mixing and pulping the ferrous methanesulfonic acid leaching agent and the pretreated complex bismuth sulfide concentrate, then adding the mixture into a high-pressure kettle, simultaneously adding a surfactant, and then stirring and mixing; wherein the stirring speed is 80-1400 rpm;
s4, leaching reaction: heating the autoclave to a set temperature under the condition that the autoclave keeps stirring, then introducing oxygen, starting an oxygen pressure leaching reaction, carrying out solid-liquid separation after the reaction is carried out for 1-6 hours, and obtaining leaching slag and a bismuth-containing leaching solution.
Preferably, the bismuth content in the bismuth sulfide concentrate is 15-35% by mass, the sulfur content is 15-35% by mass, and the iron content is 15-35% by mass.
Preferably, after the wet grinding treatment of the bismuth sulfide concentrate, the particle size of the bismuth sulfide concentrate is 3-100 um.
Preferably, the iron-containing methanesulfonic acid leaching agent contains 3-7 g/L iron and 260-380 g/L methanesulfonic acid
Preferably, a surfactant is added in the leaching process, wherein the surfactant is any one of calcium lignosulfonate, sodium lignosulfonate, lignite and quebracho, and the dosage of the surfactant is 0.1-0.9% of the mass of the bismuth concentrate raw material.
Preferably, the leaching temperature is 50-150 ℃.
Preferably, the partial pressure of the leaching oxygen is 0.4-1.5 MPa.
Preferably, the leaching time is 1-6 h.
The invention provides an oxygen pressure leaching method of a methanesulfonic acid system bismuth sulfide concentrate, which has the following beneficial effects:
(1) the method for leaching bismuth sulfide concentrate has high leaching rate of bismuth up to more than 93 percent, is simple to operate, can efficiently dissolve bismuth to obtain a sulfur product, and does not generate SO2And has the advantage of environmental protection.
(2) The invention adopts the methanesulfonic acid as a leaching system, has high bismuth solubility, low toxicity and low corrosivity, reduces the pressure on the environment, properly prolongs the service life of equipment, and further greatly reduces the production cost, so that the process has obvious advantages in large-scale industrial application.
Detailed Description
Example 1:
the process principle of the invention is as follows:
2Bi2S3+12CH3SO3H+3O2=4Bi(CH3SO3)3+6S0+6H2O
an oxygen pressure leaching method of a methanesulfonic acid system bismuth sulfide concentrate comprises the following steps:
taking 125g of bismuth sulfide concentrate (containing Bi 23%), carrying out ore grinding work, grinding the bismuth sulfide concentrate to 97% to ensure that the granularity of the concentrate is less than 30 mu m, adding a leaching agent containing 400g/L of methanesulfonic acid and 9g/L of iron to ensure that the mass ratio of the volume of liquid to solid is 8:1, then adding a surfactant, wherein the surfactant is calcium lignosulfonate, the adding amount is 0.7% of the mass of the raw material, adding the prepared ore pulp into an autoclave, heating the autoclave to 135 ℃, controlling the temperature to be stable at 135 ℃, then introducing oxygen, controlling the pressure to be 1.0MPa, stirring speed to 400 r/min, reacting for 2h, carrying out an oxygen pressure leaching process, and carrying out liquid-solid separation after the reaction is finished.
Example 2:
the process principle of the invention is as follows:
2Bi2S3+12CH3SO3H+3O2=4Bi(CH3SO3)3+6S0+6H2O
an oxygen pressure leaching method of a methanesulfonic acid system bismuth sulfide concentrate comprises the following steps:
taking 125g of bismuth sulfide concentrate (containing 23% Bi), carrying out ore grinding, grinding the bismuth sulfide concentrate to 97% to ensure that the granularity of the concentrate is less than 50 mu m, adding a leaching agent containing 280g/L of methanesulfonic acid and 9g/L of iron to ensure that the mass ratio of the volume of liquid to solid is 8:1, then adding a surfactant, wherein the surfactant is sodium lignosulfonate, the adding amount of the sodium lignosulfonate is 0.7% of the mass of the raw material, adding the prepared ore pulp into an autoclave, heating the autoclave to 135 ℃, controlling the temperature to be stable at 135 ℃, then introducing oxygen, controlling the pressure to be 1.0MPa, stirring speed to 400 r/min, reacting for 2h, carrying out an oxygen pressure leaching process, and carrying out liquid-solid separation after the reaction is finished.
Example 3:
the process principle of the invention is as follows:
2Bi2S3+12CH3SO3H+3O2=4Bi(CH3SO3)3+6S0+6H2O
an oxygen pressure leaching method of a methanesulfonic acid system bismuth sulfide concentrate comprises the following steps:
taking 100g of bismuth sulfide concentrate (containing Bi 23%), carrying out ore grinding work, grinding the bismuth sulfide concentrate to 97%, enabling the granularity of the concentrate to be smaller than 30 mu m, adding a leaching agent containing 300g/L of methanesulfonic acid and 5g/L of iron, enabling the mass ratio of the volume of liquid to solid to be 10:1, then adding a surfactant, wherein the surfactant is lignite, the adding amount of the lignite is 0.6% of the mass of the raw material, adding the prepared ore pulp into an autoclave, heating the autoclave to 90 ℃, controlling the temperature to be stable at 90 ℃, then introducing oxygen, controlling the pressure in the autoclave to be 0.8MPa, reacting for 2h, carrying out an oxygen pressure leaching process, and carrying out liquid-solid separation after the reaction is finished.
Example 4:
the process principle of the invention is as follows:
2Bi2S3+12CH3SO3H+3O2=4Bi(CH3SO3)3+6S0+6H2O
an oxygen pressure leaching method of a methanesulfonic acid system bismuth sulfide concentrate comprises the following steps:
taking 250g of bismuth sulfide concentrate (containing Bi 23%), carrying out ore grinding work, grinding the bismuth sulfide concentrate to 97%, enabling the granularity of the concentrate to be smaller than 30 mu m, adding a leaching agent containing 280g/L of methanesulfonic acid and 3g/L of iron, enabling the mass ratio of the volume of liquid to solid to be 4:1, then adding a surfactant, wherein the surfactant is quebracho tree bark, the adding amount of the quebracho tree bark is 0.7% of the mass of the raw material, adding the prepared ore pulp into an autoclave, heating the autoclave to 110 ℃, controlling the temperature to be stable at 110 ℃, then introducing oxygen, controlling the pressure in the autoclave to be 1.0MPa, stirring speed to be 400 r/min, reacting for 3h, carrying out an oxygen pressure leaching process, and carrying out liquid-solid separation after the reaction is finished.
The data obtained according to examples 1 to 4 are shown in the following table:
| 1. examples of the embodiments | 2. Leaching rate of bismuth | 3. The slag containing bismuth |
| 4. Example 1 | 5. 96.8% | 6. 2.4% |
| 7. Example 2 | 8. 86.7% | 9. 5.7% |
| 10. Example 3 | 11. 91.67% | 12. 3.6% |
| 13. Example 4 | 14. 88.7% | 15. 5.1% |
The experimental data show that the oxygen pressure leaching technology is adopted, the leaching rate of bismuth is high, the bismuth content in slag is low, the method is simple to operate, bismuth can be efficiently dissolved out, a sulfur product is obtained, SO2 is not generated, and the method has the advantages of environmental protection and convenience in popularization and use.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (8)
1. An oxygen pressure leaching method of a methanesulfonic acid system bismuth sulfide concentrate is characterized by comprising the following steps:
s1, pretreatment of materials: adding the bismuth sulfide concentrate into a vertical mill, finely grinding the bismuth sulfide concentrate by using the vertical mill, and drying the screened material for later use;
s2, preparing liquid: adding iron powder into a methanesulfonic acid solution properly according to an iron-containing phase and iron content in the material, and then stirring the solution to fully mix the iron powder and the methanesulfonic acid solution to obtain an iron-containing methanesulfonic acid leaching agent;
s3, mixing: mixing and pulping the ferrous methanesulfonic acid leaching agent and the pretreated complex bismuth sulfide concentrate, then adding the mixture into a high-pressure kettle, simultaneously adding a surfactant, and then stirring and mixing; wherein the stirring speed is 80-1400 rpm;
s4, leaching reaction: heating the autoclave to a set temperature under the condition that the autoclave keeps stirring, then introducing oxygen, starting an oxygen pressure leaching reaction, carrying out solid-liquid separation after the reaction is carried out for 1-6 hours, and obtaining leaching slag and a bismuth-containing leaching solution.
2. The oxygen pressure leaching method of the bismuth sulfide concentrate in the methanesulfonic acid system according to claim 1, wherein the bismuth sulfide concentrate contains 15 to 35 mass% of bismuth, 15 to 35 mass% of sulfur and 15 to 35 mass% of iron.
3. The oxygen pressure leaching method for the bismuth sulfide concentrate in the methanesulfonic acid system according to claim 1, wherein the particle size of the bismuth sulfide concentrate after the wet grinding treatment of the bismuth sulfide concentrate is 3-100 um.
4. The oxygen pressure leaching method of the methanesulfonic acid system bismuth sulfide concentrate according to claim 1, wherein the iron-containing methanesulfonic acid leaching agent contains 250-600 g/L methanesulfonic acid.
5. The oxygen pressure leaching method of bismuth sulfide concentrate in a methanesulfonic acid system according to claim 1, wherein a surfactant is added during leaching, wherein the surfactant is any one of calcium lignosulfonate, sodium lignosulfonate, lignite and quebracho, and the amount of the surfactant is 0.1-0.9% of the raw material mass of the bismuth concentrate.
6. The oxygen pressure leaching method of bismuth sulfide concentrate in methanesulfonic acid system according to claim 1, wherein the leaching temperature is 50-150 ℃.
7. The oxygen pressure leaching method of the methanesulfonic acid system bismuth sulfide concentrate according to claim 1, wherein the leaching oxygen partial pressure is 0.4-1.5 MPa.
8. The oxygen pressure leaching method of the methanesulfonic acid system bismuth sulfide concentrate according to claim 1, wherein the leaching time is 1-6 h.
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|---|---|---|---|---|
| CN105779789A (en) * | 2016-03-11 | 2016-07-20 | 中南大学 | Wet method for separating bismuth from antimony |
| CN105886797A (en) * | 2015-01-25 | 2016-08-24 | 昆明冶金高等专科学校 | Method for preparing sponge indium from polymetallic sulfide material |
| CN106834679A (en) * | 2017-02-22 | 2017-06-13 | 中南大学 | The method that lead in concentrate of lead sulfide ore is leached in two sections of adverse current pressure oxidations of sulfonic acid solutions |
| CN109913647A (en) * | 2019-04-25 | 2019-06-21 | 江西自立环保科技有限公司 | A kind of wet treatment method recycling copper, zinc in bismuth chats |
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| US20130252798A1 (en) * | 2012-03-21 | 2013-09-26 | National Tsing Hua University | Metallic sulfide photocatalyst for carbon dioxide reduction and the preparation for the same |
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105886797A (en) * | 2015-01-25 | 2016-08-24 | 昆明冶金高等专科学校 | Method for preparing sponge indium from polymetallic sulfide material |
| CN105779789A (en) * | 2016-03-11 | 2016-07-20 | 中南大学 | Wet method for separating bismuth from antimony |
| CN106834679A (en) * | 2017-02-22 | 2017-06-13 | 中南大学 | The method that lead in concentrate of lead sulfide ore is leached in two sections of adverse current pressure oxidations of sulfonic acid solutions |
| CN109913647A (en) * | 2019-04-25 | 2019-06-21 | 江西自立环保科技有限公司 | A kind of wet treatment method recycling copper, zinc in bismuth chats |
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