CN107868875B - A method of recycling lead and tellurium from lead anode slurry - Google Patents
A method of recycling lead and tellurium from lead anode slurry Download PDFInfo
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- CN107868875B CN107868875B CN201711296881.6A CN201711296881A CN107868875B CN 107868875 B CN107868875 B CN 107868875B CN 201711296881 A CN201711296881 A CN 201711296881A CN 107868875 B CN107868875 B CN 107868875B
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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
- C22B7/00—Working up raw materials other than ores, e.g. scrap, to produce non-ferrous metals and compounds thereof; Methods of a general interest or applied to the winning of more than two metals
- C22B7/006—Wet processes
- C22B7/007—Wet processes by acid leaching
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B19/00—Selenium; Tellurium; Compounds thereof
- C01B19/02—Elemental selenium or tellurium
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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
- C22B11/00—Obtaining noble metals
- C22B11/04—Obtaining noble metals by wet processes
- C22B11/042—Recovery of noble metals from waste materials
- C22B11/044—Recovery of noble metals from waste materials from pyrometallurgical residues, e.g. from ashes, dross, flue dust, mud, skim, slag, sludge
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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
- C22B13/00—Obtaining lead
- C22B13/04—Obtaining lead by wet processes
- C22B13/045—Recovery from waste materials
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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
- C22B7/00—Working up raw materials other than ores, e.g. scrap, to produce non-ferrous metals and compounds thereof; Methods of a general interest or applied to the winning of more than two metals
- C22B7/006—Wet processes
- C22B7/008—Wet processes by an alkaline or ammoniacal leaching
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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 method that the invention discloses a kind of to recycle lead and tellurium from lead anode slurry, includes the following steps: to cure: hydrogen peroxide being added in lead anode slurry after mixing evenly, curing is stood, obtains curing slag；Selectively leaching: lead electrolytic solution leaching is added into curing slag obtained in maturation stage, obtains leachate A and leached mud A；Leachate A returns to Selectively leaching process circulating leaching, after lead concentration reaches 90g/L ~ 150g/L in leachate A, sulfuric acid is added to obtain lead sulfate, recycles lead；Alkali leaches: adding the leaching of alkali leaching agent into leached mud A obtained in Selectively leaching step, leachate B and leached mud B are obtained, leachate B returns to alkali leaching process circulating leaching, after tellurium concentration reaches 20g/L ~ 30g/L in leachate B, electrolysed leachate B recycles tellurium.In the present invention treated lead anode slurry, the rate of recovery that lead tolerance can reduce by 70% or more, tellurium can reach 90% or more.
Description
Technical field
The invention belongs to lead anode slurry wet processing technique fields, and in particular to recycled from lead anode slurry to one kind lead and
The method of tellurium.
Background technique
Lead anode slurry is the product of lead bullion electrorefining, be enriched in lead anode slurry noble metal, dissipated metal and other have
Valence metal.During pyrometallurgical smelting, valuable metal is all entered in corresponding finished product or semi-finished product with base metal, final
When electrorefining, it is segregated into lead anode slurry with base metal.Although lead concentrate is due to refining splicer's skill and refines leady raw materials not
Together, the lead anode slurry component difference of institute's output is larger, but the main component of generally lead anode slurry is in following weight percent model
In enclosing: gold 0.03 ~ 0.1%, silver 3 ~ 8%, antimony 20 ~ 40%, bismuth 8 ~ 20%, tellurium 0.5 ~ 2%, lead 10 ~ 40%.Compared to traditional blast furnace
Lead is refined, lead tolerance, amount containing tellurium be all using the method for base husband's Saite furnace single step smelting lead, in the lead anode slurry obtained after electrorefining
Increasing considerably --- lead tolerance can reach 30%-40%, amount containing tellurium can reach 0.7%-1.2%.The raising of lead tolerance causes lead positive
Pole mud yield is consequently increased, but the grade of the rare precious metals such as gold, silver in lead anode slurry is greatly lowered, to be subsequent
Rare precious metal in recycling lead anode slurry causes very big influence, influences the rate of recovery of the rare precious metals such as tellurium, gold, silver, and significantly
Increase the technical problem of cost recovery.Rare precious metal occupies critically important status in national economy, extracts from lead anode slurry
These metals can obtain very big economic benefit.At the same time, content of the tellurium in lead anode slurry has had 1.0% or so
The standby value that tellurium is directly recycled from lead anode slurry.Tellurium in traditional lead anode slurry is by during gold, silver recovery process
Byproduct --- tellurium slag is recycled, and the rate of recovery is very low, only 50% or so.
Small, process equipment is simple, scale is unrestricted, valuable metal synthetical recovery with investing for wet-treating lead anode slurry
The advantages that rate is high, with short production cycle.Frequently with acid medium potassium cloride, so that the metallic elements such as antimony, bismuth, copper is entered pickle liquor
Middle recycling, other enter slag in recycles, in arsenic, the higher lead anode slurry of antimony content, the antimony of existence form complexity be then not easy by
It leaches, the presence of arsenic will directly affect the recycling of tellurium, to influence recovery efficiency.
Summary of the invention
The technical problem to be solved by the present invention is to overcome the shortcomings of to mention in background above technology and defect, provide one
The method that kind recycles lead and tellurium from lead anode slurry.Using in the present invention treated lead anode slurry, lead tolerance can reduce by 70% with
Upper, tellurium the rate of recovery can reach 90% or more, also have at low cost, simple process, environment dirty using this method processing lead anode slurry
Contaminate the advantages that small.
To achieve the above object, technical solution proposed by the present invention are as follows:
A method of it recycling lead and tellurium from lead anode slurry, includes the following steps:
(1) it cures: hydrogen peroxide being added in lead anode slurry after mixing evenly, curing is stood, obtain curing slag；
(2) Selectively leaching: lead electrolytic solution leaching is added into curing slag obtained in maturation stage, is leached
Liquid A and leached mud A；Leachate A return Selectively leaching process circulating leaching, when in leachate A lead concentration reach 90g/L ~
After 150g/L, sulfuric acid is added to obtain lead sulfate, recycles lead；
(3) alkali leaches: adding the leaching of alkali leaching agent into leached mud A obtained in Selectively leaching step, is soaked
Liquid B and leached mud B out, leachate B return to alkali leaching process circulating leaching, when tellurium concentration reaches 20g/L ~ 30g/L in leachate B
Afterwards, electrolysed leachate B recycles tellurium；Leached mud B can be used for recycling gold, silver.
Above-mentioned method, it is preferred that in step (1), the dosage of hydrogen peroxide accounts for the 10% ~ 15% of lead anode slurry weight；Lead sun
The moisture content of pole mud is 35%-45%.Addition hydrogen peroxide purpose is, makes elementary lead in lead anode slurry, intermediate alloy lead, centre
Alloy tellurium is oxidized to oxidation state, and the chemical reaction occurred in maturation stage is as follows:
Pb+H2O2= PbO↓+H2O；
PbTe+3H2O2= PbO↓+ TeO2↓+3H2O；
AgTe+2H2O2= Ag↓+ TeO2↓+2H2O；
Above-mentioned method, it is preferred that in step (1), the curing time is 24 ~ 72 hours, and curing temperature is 10 ~ 90 DEG C.
Above-mentioned method, it is preferred that be that lead electrolytic solution is added in 3 ~ 6:1 by liquid-solid ratio (weight ratio) in step (2).
Above-mentioned method, it is preferred that in step (2), extraction time is 2 ~ 3 hours, 55 DEG C ~ 65 DEG C of extraction temperature, is stirred
Speed is 300 r/min ~ 500r/min.The hydrogen ion in PbO and acidic electrolysis bath in curing slag reacts, and keeps lead first
Element is stayed in leachate in a manner of liquid, and the chemical reaction occurred in Selectively leaching step is as follows: PbO+H+= Pb2++
H2O。
Above-mentioned method, it is preferred that in step (3), alkali leaching agent is added by 3 ~ 5:1 of liquid-solid ratio, alkali leaching agent is concentration
For 100 g/L ~ 200g/L sodium hydroxide solution.
Above-mentioned method, it is preferred that in step (3), extraction temperature is 75 DEG C ~ 90 DEG C, and extraction time is 2 ~ 4 hours, is stirred
Mix 300 r/min of speed ~ 500r/min.
Above-mentioned method, it is preferred that in step (2), the additional amount of sulfuric acid is 1.0 ~ 1.1 times of theoretical amount.
Hydrogen peroxide oxidation of the present invention can leach the inside in the earth of positive pole, keep oxidation effectiveness good, can not only aoxidize main metal, and
And tellurium not oxidizable in air can be aoxidized.Meanwhile the present invention uses lead electrolytic solution Selectively leaching, lead can be made to leach,
The lead content in the earth of positive pole is reduced, leachate can both be made lead sulfate product, can also return in lead electrolytic cell and recycle lead.This
Invention while lead, can also directly recycle tellurium, solve lead in lead anode slurry and contain in reducing the lead anode slurry containing high lead content
Amount is too high, influences the rate of recovery of the rare precious metals such as tellurium, gold, silver and greatly increases the technical problem of cost recovery.
Compared with prior art, the invention has the benefit that
(1) present invention adds hydrogen peroxide in lead anode slurry, and hydrogen peroxide, which penetrates into various pieces in lead anode slurry, makes lead oxygen
Change uniformly, while lead oxide also can slowly bored ripe oxidation wherein most tellurium so that this method treated lead anode slurry
In, the rate of recovery that lead tolerance can reduce by 70% or more, tellurium can reach 90% or more.
(2) method of the invention handles lead anode slurry, and at low cost, simple process, environmental pollution are small.
(3) wastewater treatment is simple during method of the invention, and leachate slightly can directly return to lead electrolysis after pretreatment
Recycle lead.
Specific embodiment
To facilitate the understanding of the present invention, invention herein is done below in conjunction with preferred embodiment and more comprehensively, is meticulously retouched
It states, but protection scope of the present invention is not limited to following specific embodiments.
Unless otherwise defined, all technical terms used hereinafter are generally understood meaning phase with those skilled in the art
Together.Technical term used herein is intended merely to the purpose of description specific embodiment, and it is of the invention to be not intended to limitation
Protection scope.
Unless otherwise specified, various raw material, reagent, the instrument and equipment etc. used in the present invention can pass through city
Field is commercially available or can be prepared by existing method.
Embodiment 1:
A kind of method recycling lead and tellurium from lead anode slurry of the present embodiment, includes the following steps:
(1) the lead anode slurry 500g(moisture content 40% that taking lead tolerance is 30%, amount containing tellurium is 0.7%), it is 25% that concentration, which is added,
Hydrogen peroxide 45mL(dioxygen water density be 1.1g/mL), after mixing evenly, at normal temperature place 24 hours, obtain curing slag；
(2) 1L lead electrolytic solution is added to above-mentioned curing slag and carries out Selectively leaching, under the conditions of temperature is 55 DEG C, stirring leaching
2 hours out, mixing speed 500r/min obtained leachate A and leached mud A；Leachate A returns to Selectively leaching process
Circulating leaching 4 times, after lead concentration reaches 90g/L ~ 150g/L in leachate A (final filtration obtain 1.2L leachate A and
165g leached mud A), 1.0 times of sulfuric acid of theoretical amount is added into leachate A, recycles lead；Through detecting: leaded in leached mud A
It is 1.25% that amount, which is 9.98%, amount containing tellurium,；
(3) hydrogen that 500mL concentration is 120g/L is added in the 165g leached mud A that Xiang Shangshu Selectively leaching step obtains
Sodium hydroxide solution carries out alkali leaching, and under the conditions of temperature is 80 DEG C, leaching 2 hours, mixing speed 400r/min was obtained
Leachate B and leached mud B, leachate B are returned alkali leaching process circulating leaching 4 times, when tellurium concentration reaches 20gL in leachate B
After ~ 30g/L (final filtration obtains 520mL leachate and 158g leached mud), electrolysed leachate B recycles tellurium.Through detecting: leaching
Concentration containing tellurium is 3.56gL in liquid B, and leached mud B lead tolerance is 8.5%, and the leaching rate of tellurium is 90%.
Embodiment 2:
A kind of method recycling lead and tellurium from lead anode slurry of the present embodiment, includes the following steps:
(1) the lead anode slurry 500g(moisture content 40% that taking lead tolerance is 35%, amount containing tellurium is 1.0%), it is 25% that concentration, which is added,
Hydrogen peroxide 54mL(dioxygen water density be 1.1g/mL), after mixing evenly, place 48 hours, cured under the conditions of 55 DEG C
Slag；
(2) 1L lead electrolytic solution is added to above-mentioned curing slag and carries out Selectively leaching, under the conditions of temperature is 60 DEG C, stirring leaching
3 hours out, mixing speed 500r/min obtained leachate A and leached mud A；Leachate A returns to Selectively leaching process
Circulating leaching 4 times, after lead concentration reaches 90g/L ~ 150g/L in leachate A (final filtration obtain 1.2L leachate A and
155g leached mud A), 1.0 times of sulfuric acid of theoretical amount is added into leachate A, recycles lead；Through detecting: leached mud A lead tolerance
It is 1.9% for 8.2%, amount containing tellurium；
(3) hydrogen-oxygen that 500mL concentration is 150g/L is added in the 155g leached mud A that Xiang Shangshu Selectively leaching step obtains
Change sodium solution and carry out alkali leaching, under the conditions of temperature is 85 DEG C, leaching 3 hours, mixing speed 400r/min was leached
Liquid B and leached mud B, leachate B return alkali leaching process circulating leaching 4 times, when in leachate B tellurium concentration reach 20gL ~
After 30g/L (final filtration obtains 520mL leachate and 150g leached mud), electrolysed leachate B recycles tellurium.Through detecting, leachate
The concentration of tellurium is 6.2g/L in B, and lead tolerance is 6.25% in leached mud B, and the leaching rate of tellurium is 92%.
Embodiment 3:
A kind of method recycling lead and tellurium from lead anode slurry of the present embodiment, includes the following steps:
(1) the lead anode slurry 500g(moisture content 40% that taking lead tolerance is 40%, amount containing tellurium is 1.2%), it is 25% that concentration, which is added,
Hydrogen peroxide 68mL(dioxygen water density be 1.1g/mL), after mixing evenly, place 72 hours, cured under the conditions of 85 DEG C
Slag；
(2) 1L lead electrolytic solution is added to above-mentioned curing slag and carries out Selectively leaching, under the conditions of temperature is 60 DEG C, stirring leaching
3 hours out, mixing speed 500r/min obtained leachate A and leached mud A；Leachate A returns to Selectively leaching process and follows
Ring leaches 4 times, and (final filtration obtains 1.2L leachate A and 142g after lead concentration reaches 90g/L ~ 150g/L in leachate A
Leached mud A), 1.0 times of sulfuric acid of theoretical amount is added into leachate A, recycles lead；Through detecting: lead tolerance is in leached mud A
6.3%, amount containing tellurium is 2.5%；
(3) hydrogen-oxygen that 500mL concentration is 200g/L is added in the 142g leached mud A that Xiang Shangshu Selectively leaching step obtains
Change sodium solution and carry out alkali leaching, under the conditions of temperature is 90 DEG C, leaching 4 hours, mixing speed 500r/min was leached
Liquid B and leached mud B, leachate B return alkali leaching process circulating leaching 4 times, when in leachate B tellurium concentration reach 20gL ~
After 30g/L (final filtration obtains 550mL leachate and 130g leached mud), electrolysed leachate B recycles tellurium.Through detecting: leachate
The concentration of tellurium is 6.8g/L in B, and the content of lead is 6.0% in leached mud B, and the leaching rate of tellurium is 95%.
Claims (6)
1. a kind of method for recycling lead and tellurium from lead anode slurry, which comprises the steps of:
(1) it cures: hydrogen peroxide being added in lead anode slurry after mixing evenly, curing is stood, obtain curing slag；Wherein, hydrogen peroxide
Dosage account for the 10%-15% of lead anode slurry weight；Curing time is 24~72 hours, and curing temperature is 10~90 DEG C；
(2) Selectively leaching: lead electrolytic solution leaching is added into curing slag obtained in maturation stage, obtains leachate A
With leached mud A；Leachate A returns to Selectively leaching process circulating leaching, when lead concentration reaches 90g/L~150g/ in leachate A
After L, sulfuric acid is added to obtain lead sulfate, recycles lead；
(3) alkali leaches: adding the leaching of alkali leaching agent into leached mud A obtained in Selectively leaching step, obtains leachate B
With leached mud B, leachate B returns to alkali leaching process circulating leaching, after tellurium concentration reaches 20g/L~30g/L in leachate B,
Electrolysed leachate B recycles tellurium.
2. the method according to claim 1, wherein being that lead electrolysis is added in 3~6:1 by liquid-solid ratio in step (2)
Liquid.
3. leaching temperature the method according to claim 1, wherein extraction time is 2~3 hours in step (2)
55 DEG C~65 DEG C of degree, mixing speed are 300r/min~500r/min.
4. described in any item methods according to claim 1~3, which is characterized in that in step (3), add by 3~5:1 of liquid-solid ratio
Enter alkali leaching agent, alkali leaching agent is the sodium hydroxide solution that concentration is 100g/L~200g/L.
5. described in any item methods according to claim 1~3, which is characterized in that in step (3), extraction temperature be 75 DEG C~
90 DEG C, extraction time is 2~4 hours, mixing speed .300r/min~500r/min.
6. described in any item methods according to claim 1~3, which is characterized in that in step (2), the additional amount of sulfuric acid is reason
1.0~1.1 times of stoichiometric.
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| CN104004907A (en) * | 2014-06-06 | 2014-08-27 | 郴州市金贵银业股份有限公司 | Method for separating copper from lead matte and comprehensively utilizing lead matte |
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