CN102618883B - Method for direct electrolytic refining of crude lead - Google Patents
Method for direct electrolytic refining of crude lead Download PDFInfo
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- CN102618883B CN102618883B CN201210031769.0A CN201210031769A CN102618883B CN 102618883 B CN102618883 B CN 102618883B CN 201210031769 A CN201210031769 A CN 201210031769A CN 102618883 B CN102618883 B CN 102618883B
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Abstract
The invention relates to a method for direct electrolytic refining of crude lead, and belongs to the technical field of lead refining. According to the method, the crude lead prepared by pyrometallurgy is casted into a crude lead anode, wherein the crude lead anode is sleeved inside an anode bag; and electrolysis is performed in an additive-containing perchloric acid-lead perchlorate solution electrolyte to electrically deposit the lead in the anode on the cathode, such that the high purity electrolyzed lead and the anode mud are respectively obtained from the cathode and the anode. With the present invention, the lead without a pre-refining treatment can be directly subjected to electrolytic refining to obtain the pure lead with the purity more than 99.99% and the anode mud doped with noble metals, such that the recovery rate of the noble metals can be substantially improved so as to provide greater economic benefits.
Description
Technical field
The invention belongs to plumbous refining techniques field, relate to a kind of Direct Electrolysis method of lead bullion, the lead bullion specifically existing pyrometallurgical smelting process being obtained directly utilizes electrochemical method to carry out electrorefining to obtain the method for high purity electrolytic lead and residual valuable metal.
Background technology
Along with developing rapidly of the vehicles such as automobile, lead-acid cell, as the indispensable chemical power source of these vehicles, also obtains swift and violent development.According to statistics, China has reached more than 3,500,000 tons the plumbous output of 2010, and wherein nearly 80% lead is used to the manufacture field of lead-acid cell.Because valve-controlled type maintenance-free lead-acid cell is in order to reduce the self-discharge coefficient of battery, the foreign matter content of leady raw materials is proposed to very high requirement.Usually, in order to ensure quality and the work-ing life of lead-acid cell, the main raw material that producer is mainly used the metallic lead of purity more than 99.99% to produce as lead-acid cell.Regrettably, the purity of the metallic lead that traditional lead ore or waste lead acid battery obtain through pyrometallurgical smelting is generally 95-99%, and the lead bullion of these low-purity must could be accepted by fields such as lead-acid celies through refining repeatedly.At present plumbous refining techniques mainly contains two kinds of pyrorefining and electrorefinings in the world, because electrorefining can more effectively reclaim the valuable metals such as the copper, silver and the bismuth that are mingled with in lead, thus electrolytic refining process in the world especially China be widely used.
Existing electrolytic refining process, is called again hereby purifying method of cypress.It is to be proposed by A.G.Betts in 1901, and starts to obtain industrial applications in 1902, and its principal character is to make electrolytic solution with the aqueous solution of plumbous silicofluoride and silicofluoric acid composition.This electrolysis process need to adopt the lead bullion of preliminary refining, especially needs the lead bullion of pre-decopper(ing) and tin just can cast anode, and thin pure lead flake is negative electrode, is filling 0.3-0.5mol/L PbSiF
6(with 0.4-0.6mol/L H
2siF
6in the electrolyzer of () mixed solution, carry out electrorefining and obtain highly purified catholyte lead and the surperficial anode anode scrap with the anode sludge.Silicofluoric acid purifying method, through this development in more than 100 years, has become the classics of our times electrolytic lead refining.Its advantage is stably to obtain purity up to more than 99.99% pure lead, and its shortcoming is also paid close attention to by people day by day simultaneously.Main drawback is as follows:
1, because the metal such as copper and tin is easy to pollute silicofluoric acid-plumbous silicofluoride electrolytic solution, the lead bullion that the 95-98% lead bullion that therefore traditional pyrometallurgical smelting obtains obtains 99% purity conventionally after pyrogenic process preliminary refining removal of impurities more than 1-2 road just can be used to existing electrorefining technique.We find now, and the process at the lead bullion of 95-98% through 2 road pyrorefining copper removal tin, is usually being mingled with the loss of the rare precious metals such as a large amount of Ag and Bi.The silver content of 98% lead bullion that the golden lead of for example Henan light is certain batch is 0.51%, but after 2 road pyrogenic process preliminary refining techniques, its purity is that the silver content of 99% lead bullion is reduced to 0.17%, and this directly causes there is 3400g silver because being run off in lead bullion per ton in pyrogenic process preliminary refining technique.
2, silicofluoric acid easily volatilizees and resolves into poisonous HF and SiF in the time being heated
4this technique generally can only adopt rarer silicate fluoride solution, and electrolysis temperature general control is at lower temperature (30-45 DEG C), this rarer electrolytic solution and lower working temperature make the specific conductivity of electrolytic solution lower, ion velocity of diffusion is slower simultaneously, thereby the current density that electrolytic process can bear is also lower, is generally 180-200A/m
2, produce up to the groove of 0.4-0.5V and press at electrolytic process simultaneously, make the electrolysis energy consumption of lead per ton up to 120-135KWh.
3, the toxicity of silicofluoric acid-plumbous silicofluoride solution is larger, adds easily volatilization of this solution itself, and this situation is more outstanding in the time of summer operation, the silicofluoric acid volatilizing from electrolyzer and decompose the poisonous SiF producing
4not only the smell is awful with HF gas, and directly endanger the healthy of operative employee.
4, in traditional refining of lead bullion technique, people directly carry out electrorefining using fluid origin lead bullion 2-3cm stereotype as anode.We find under study for action, and the anode of this simple shape is difficult to realize anodic stripping completely, and major cause is that one is that annode area is less, is difficult to bear very high current density; The 2nd, this tabular anode is the enrichment gradually along with the surperficial anode sludge at electrodeposition process, causes the impedance of electrolytic process constantly to raise, and anode only still has 50% when residual often, because of the more premature termination electrolysis of the surperficial anode sludge.The 3rd, due to the incomplete planarization on the plumbous surface of cathode electrodeposition, cause the interpole gap of this tabular anode and lead electrode to shorten gradually along with the carrying out of electrolysis, therefore the interpole gap that people have to leave in advance 4-5cm prevents interelectrode short circuit, and this longer interpole gap has been aggravated again the rising of electrolysis energy consumption.
Although in recent years, people once studied the system such as perchlorhydria and NaOH in the research in plumbous electrolysis field, but because lead chloride is less at hydrochloric acid or the solubleness of plumbous oxide in NaOH solution, or do not have effective galvanic deposit additive to cause galvanic deposit lead to present a kind of loose dendrite, very easily in melting process, be again oxidized and fail industrialization, thereby the method that current industrial electrolytic lead refining generally adopts is still the Bai Zifa based on silicofluoric acid medium.
The electrolytic lead smelting method (CN200810232653.7) of the people such as such as Gao Wenjie invention reported silicofluoric acid concentration adjusted to 110-149g/L, and lead content is 70-110g/L, adopts forward and reverse DC electrolysis method to smelt plumbous method.The method has been eliminated lead dendritic crystal to a certain extent, but in the reversible circulation stage, the lead of just galvanic deposit is dissolved in electrolytic solution again, causes this part electricity loss of energy.In the production method (CN200810097208.4) of the high purity lead of Ma Shengjun invention, reported from lead sulfide ore and waste lead acid battery, smelt obtain in silicofluoric acid and plumbous silicofluoride electrolytic solution, carry out electrorefining and obtain the method for high purity lead (99.99%) containing stibium crude lead.This invention is that the distance by controlling electrolyzer Anodic and negative electrode is installed, and has obtained more than 99.996% pure lead, and regrettably, electrolytic process still needs the electrolyzer of 0.45-0.48V to press, and causes electrolysis energy consumption higher.Also there is people from environmental, once used and in alkaline system, carry out plumbous electrolysis.For example Chen Wei flat (Hunan University's journal, 1996,23 (6): 111-116) utilizes NaOH and KNaC
4h
4o
6under the help of gelatin additive, carry out the electrolysis of lead plaster and reclaim the lead in lead plaster, regrettably, this galvanic deposit can only obtain spongiform lead powder.And relevant people utilize alkaline NaOH solution to carry out the method rarely seen report always of lead bullion electrorefining.Because the dissolving power of plumbous oxide in simple NaOH solution is limited, add and do not find that effective galvanic deposit additive gets off to control plumbous electrodeposition process, the loose porous electrolytic lead obtaining very much, the lead of this high-ratio surface is easy in melting process and airborne oxygen generation oxidizing reaction, these are all unfavorable for the industrial application of NaOH system electrolysis, cause plumbous alkaline system electrolysis to be failed developed always, do not realize so far industrial applications.
The inventor finds, the lead bullion that pyrometallurgical smelting directly obtains is except the metallic lead that contains 95-98% purity, the alloy that also contains the alloy grid of associated metal in lead ore or lead-acid cell is directly mixed in lead bullion in high melt process, the metals such as such as Ag, As, Bi, Cu, Sn, Sb, Cd and Fe.As a rule, in 95-98% lead bullion, mainly contain the simple substance such as the As of Sb, 0.1-0.4% and the Bi of 0.1-0.4% of Ag, the 0.1-2.0% of Cu, 0.1-0.5% that weight percent is 0.3-0.7%, and the impurity such as Sn and Fe of trace.
The principle of electrorefining is actual is to carry out optionally stripping and electrodeposition process according to the difference of electropotential between element.Owing to being mingled with the foreign metal of its electropotential corrigendum in lead, for example Bi, Cu, Sb and Ag4 kind metal simple-substance and nonmetal As, because their electropotentials in acidity are as follows respectively:
Cu-2e＝Cu
2+ (E
A 0＝0.337V)
Ag-e＝Ag
+ (E
A 0＝0.7996V)
Sb-3e+3/2H
2O＝1/2Sb
2O
3+3H
+ (E
A 0＝0.152V)
As-3e+3/2H
2O＝1/2H
3AsO
3 (E
A 0＝0.247V)
When employing contains Pb and at least above-mentioned 5 kinds while carrying out refining as anode compared with the alloy of stable metal or nonmetal formation in acidic medium, because the stripping current potential of the simple substance such as Sb, Cu, Ag and Bi is far above Pb, thereby only have Pb that first anodic stripping reaction occurs, these impurity will, because staying anode surface after plumbous stripping, form the anode sludge.Same in electrolytic solution due to the Sb that does not have anodic stripping to form
3+, Cu
2+, Ag
+and Bi
3+plasma, thereby only have Pb
2+become metallic lead at negative electrode by galvanic deposit.Find by analysis, in the lead bullion of 95-98%, because the total content of various impurity in this lead is up to 2-5%, be the 2-5 of 99% purity lead bullion total impurities after pre existing decopper(ing) doubly, thereby the lead bullion of this high impurity content the more thicker anode sludge very easily occurs in electrorefining process covers, even seriously hinder the phenomenon of its inner follow-up stripping of lead bullion.
Hinder electrolysis process in order to overcome the anode sludge occurring in existing electrorefining process, people adopt the object of pyrogenic process preliminary refining significantly to reduce the content of impurity in lead bullion on the one hand, adopt and be accumulated to after certain thickness when the anode sludge on the other hand, the method for premature termination electrolysis.In addition, in lead bullion, the anodic stripping current potential of metallic copper is higher than metallic lead, but being easy under the oxygenizement of oxygen in air, it is dissolved in electrolytic solution, the trace copper of these dissolvings is because high electropotential is easy to be accompanied by plumbous electrodeposition process and separate out at negative electrode, cause the index of copper in galvanic deposit lead higher, this also has to impel people also to utilize the process of pyrogenic process preliminary refining can significantly reduce the content of the impurity such as copper tin in lead bullion, for existing electrorefining provides high quality raw material.
How to study and invent a kind of new electrolytic solution and electrorefining splicer skill thereof, develop the lead bullion that a kind of novel nontoxic non-volatile electrolytic solution directly obtains 95-98% to pyrogenic process and carry out electrorefining, significantly reduce the loss of the precious metal such as Ag in the necessary preliminary refining technique of existing refining, increase substantially labour productivity, improve employee's production environment and healthy, become the problem of needing solution badly.
Summary of the invention
The object of the invention is to overcome the deficiencies in the prior art, a kind of method of novel electrorefining lead is provided, adopting the perchloric acid-lead perchlorate solution that contains 3 kinds of additives is novel electrolyte, and employing is with the Novel anode structure of anode, the lead bullion that can directly obtain pyrometallurgical smelting carries out electrorefining, directly obtains purity up to more than 99.99% pure lead and the anode sludge that is mingled with precious metal.
One skilled in the art will appreciate that perchloric acid is a kind of very strong mineral acid, it has the acidity stronger than the mineral acid such as sulfuric acid and silicofluoric acid, and therefore it has very high dissolving power to metal.But regrettably, because its chlorine atom is in+7 valencys, thereby the perchloric acid of higher concentration often embodies stronger oxidisability, this oxidisability not only causes lead to be easy to autolyze reaction in acidic solution, thereby reduce the current efficiency of electrolytic lead refining process, and redox reaction between perchloric acid and lead, cause the deadness consumption of electrorefining procedure division perchloric acid.We find under study for action, and the perchloric acid of high density has strong oxidation capacity after being heated, but in the time that we are controlled at certain limit the concentration of perchloric acid and temperature, now perchloric acid has good stability.Further research is found, when containing in perchloric acid solution after certain density lead ion, the ability of its oxidized metal lead also decreases, therefore contain certain density lead ion or lead perchlorate at perchloric acid solution, also can increase substantially the stability of perchloric acid in the plumbous process of electrorefining.We also find under study for action in addition, add the additive 1 of minute quantity can further improve the electrodeposition efficiency of lead ion in perchloric acid solution in perchloric acid solution, reduce perchloric acid from consuming in cathodic reduction.By comprehensively effective control of the influence factor of above-mentioned 4 aspects, can provide possibility for opening up the application of perchloric acid in electrolytic lead refining.On this basis, the present invention find a kind of can promote lead bullion dissolve additive 2 significantly accelerate the dissolving of lead bullion in perchloric acid solution, thereby greatly alleviate the anode sludge that in lead bullion, high-content impurity produces to the restraining effect of dissolving, this discovery can make existing not the providing through the Direct Electrolysis refining of the lead bullion of the low-purity 95-98% of preliminary refining processing may.Finally, the present invention has also found that some can be used in the galvanic deposit additive 3 in high density perchloric acid electrolytic solution, these additives or combination of two have good scale resistance and stability, can be applied in perchloric acid electrolytic solution and not decompose, there is the plumbous effect of outstanding galvanic deposit simultaneously, make lead ion become fine and close galvanic deposit lead layer at cathode electrodeposition.
The technical solution used in the present invention is as follows.
The direct electrolytic smelting method of a kind of lead bullion, it is characterized in that, pyrometallurgical smelting to be obtained to lead bullion be cast as lead bullion anode jacket in anode, in the perchloric acid-lead perchlorate electrolysis of solutions liquid that contains additive, carry out electrolysis by the plumbous galvanic deposit in anode to negative electrode, thereby obtain respectively highly purified electrolytic lead and the anode sludge at negative electrode and anode.
Further, above-mentioned pyrometallurgical smelting obtains lead bullion or reduces plumbous fluid origin lead bullion anode is the lead bullion anode that contains space, and its apparent density is controlled at 9.9-11.0g/cm
3between.
Further, above-mentioned pyrometallurgical smelting obtains lead bullion or reduces plumbous fluid origin lead bullion anode being contained in anode, and after electrolysis completes, the anode sludge is stayed anode, and the anode sludge in separate bag obtains rare metal contained in lead bullion.
Specifically, first importance of the present invention has been to provide perchloric acid-lead perchlorate solution of the high density of high stripping capacity, and wherein the concentration of perchloric acid is 0.3-3.5mol/L, preferably 1.5-3.0mol/L, the concentration of lead perchlorate is 0.05-1.0mol/L, preferably 0.25-0.55mol/L.Wherein the working temperature of electrolytic solution is 15-75 DEG C, preferably 40-60 DEG C.The anode of electrolytic process and cathode current density are 20-1200A/m
2, preferably 100-600A/m
2.In order to overcome or to alleviate in anodic stripping process because the anode passivation phenomenon that the impurity of high-content causes, and high density and high-temperature perchloric acid solution are from the problem in cathodic reduction, in electrolytic solution of the present invention, also have 3 kinds of effective additives, suppress perchloric acid at the additive 1 of cathodic reduction, the additive 2 of promotion lead bullion dissolving and the novel plumbous additive 3 of galvanic deposit.
3 kinds of additives for perchloric acid-lead perchlorate electrolytic solution provided by the invention, specifically comprise:
1), the additive 1 that suppresses perchloric acid reduction refers to a kind of or two kinds of mixtures in tripoly phosphate sodium STPP, trisodium phosphate, boric acid or 3-methoxybenzoic acid, and their independent effective concentration is respectively between 0.01-2.5g/L, 0.05-6.0g/L, 0.01-10.0g/L and 0.01-5.0g/L.
2), promote the additive 2 of lead bullion dissolving to refer to the mixture of Monochloro Acetic Acid and acetic acid, their effective concentration is respectively 0.02-10g/L and 0.01-5.0g/L.
3), the plumbous additive 3 of novel galvanic deposit refers to a kind of or two kinds of mixtures in naphthols, gelatine, sodium lignosulfonate or tonka bean camphor, wherein the concentration of above-mentioned four kinds of additive materials corresponding 0.002-0.035g/L, 0.05-5.0g/L, 0.05-2.5g/L and 0.01-0.5g/L respectively.
Electrolytic solution of the present invention adopts the perchloric acid solution of high density, contain simultaneously and suppress perchloric acid at the additive 1 of cathodic reduction, the additive 2 of promotion lead bullion dissolving and the novel plumbous additive 3 of galvanic deposit, these three kinds of additives have effectively overcome perchloric acid from easily generating a difficult problem for dendrite arm in cathodic reduction and lead in perchloric acid medium, thereby can obtain purity up to more than 99.99% fine and close galvanic deposit lead.In electrolytic process of the present invention, adopt lower electrolyzer to press, electrolysis energy consumption is reduced, Electrolytic Energy Saving effect is remarkable, and the electrolyzer that has obtained the low 0.1-0.15V of reaching as the laboratory lab scale stage is pressed, and makes electrolysis energy consumption be reduced to 30-50KWh/t (Pb).These energy-saving and emission-reduction of studying as further excavating electrolytic lead refining process provide a kind of new important channel.
Second importance of the present invention has been to provide a kind of manufacture method of lead bullion anode of synchronous dissolving-galvanic deposit (being that before electrolysis and after electrolysis, the interpole gap between anode and negative electrode is constant) of novel applicable perchloric acid medium's electrorefining needs.One skilled in the art will appreciate that in existing refining of lead bullion technique, is to adopt lead bullion plate and the refining of the plumbous thin slice catholyte of galvanic deposit that 2-3cm is thick.Although additive can greatly promote the compactness of cathode electrodeposition lead, in actual production, the metallic lead surface that this galvanic deposit obtains is actual under electron microscope is still a kind of metallic lead forming of being piled up by crystal grain.Due to the space of crystal grain between piling up, cause the real density of this lead to be conventionally slightly less than the 11.3g/cm of fine and close plumbous (being equal to the lead bullion anode of preparing after prior art melting) after melting
3, generally at 9.9-11.0g/cm
3between.The existence of this phenomenon causes the interpole gap between electrolytic process Anodic and negative electrode constantly to be dwindled, and the interpole gap that makes people have to leave in advance at tabular anode and lead electrode 4-5cm prevents interelectrode short circuit.Novel anode provided by the invention is actually based on above-mentioned asynchronous dissolving-electro-deposition method and realizes.
The invention provides a kind of lead bullion anode that leaves in advance space, the apparent density of this lead bullion anode is controlled at 9.9-11.0g/cm
3between, basically identical with the density of cathode electrodeposition lead.It can by lead bullion surface or inside leave in advance space, reduce plumbous apparent density, can make cathode electrodeposition lead and anode lead bullion that electrolysis obtains there is close apparent density, thereby prevent the phenomenon that the interpole gap between electrolytic process Anodic and negative electrode is constantly dwindled.In other words, adopt the lead bullion anode of this low bulk density, can prevent that electrolytic process from dwindling the phenomenon that may cause short circuit between two electrodes because of interpole gap, thereby the interpole gap that can just can adopt at the electrolysis initial stage the low 1-3cm of reaching, the even low 0.2-1.0cm of reaching interpole gap significantly reduces the energy consumption phenomenon that in electrolytic process, the impedance of electrolytic solution causes.This lead bullion anode that leaves in advance space, generally can adopt conventional method can control and reduce plumbous apparent density, if casting is with the lead bullion anode of thin trace or leave the methods such as air in inside and realize.
The 3rd importance of the present invention has been to provide a kind of applicable lead bullion anode and dissolved needed anode completely, and this anode adopts dense membrane paper that can acid corrosion-resistant to make, it be at electrorefining protheca on anode and bring into play its effect.This anode provides three kinds of significant effects, 1) be significantly to reduce the oxidation of airborne oxygen antianode lead bullion and alloy thereof and the oxidation stripping of copper in the dissolving, the especially lead bullion that cause.2) be that the anode of this densification can prevent that the stirring of because of metal electrolytic solution in some fine mud shape anode things that anodic dissolution processes produces from flowing and depositing to cathode surface, thus the reduction problem of the plumbous purity of the negative electrode causing.3) be that this anode can be contained in the whole anode sludge that stay after the stripping of anode lead bullion in sack, for the refinement of precious metal in the later stage anode sludge provides convenience.Experiment shows, this anode can adopt a kind of or two kinds of fibers in polyvinyl alcohol fiber, viscose fiber, polyvinyl chloride barrier film, polypropylene or polycthylene grafted mould material to be prepared from, and the gauge control of anode is at 0.03-0.8mm.
Generally speaking, the technical scheme that the present invention preferably adopts is as follows.The direct electrolytic smelting method of a kind of lead bullion, first pyrometallurgical smelting to be obtained to lead bullion or the plumbous lead bullion anode that contains space that is cast as of reduction, then be contained in anode jacket, under the effect of perchloric acid-lead perchlorate and additive, by electrolysis by plumbous galvanic deposit in anode to negative electrode, thereby obtain highly purified electrolytic lead and the anode sludge at negative electrode and anode, the anode sludge finally separating in anode jacket obtains rare metal contained in lead bullion.
In an implementation process of the present invention, we need to, according to the height of the temperature of electrolytic solution in electrolyzer, control the current density of lead bullion anode.Although the present invention is owing to having adopted the perchloric acid of high density and higher electrolysis temperature, these two factors can increase substantially the specific conductivity of electrolytic solution, and therefore constant-current electrolysis of the present invention can be carried out under higher current density.According to experiment, different temperature can be selected different current densities, and when the temperature of electrolytic solution is during in 30-45 DEG C, constant-current electrolysis adopts 20-300A/m
2current density be advisable.When electrolyte temperature is during in 45-60 DEG C, electrolytic solution can adopt 300-600A/m
2current density.When electrolyte temperature is during in 60-75 DEG C, the current density of electrorefining process can adopt 600-1200A/m
2level.
In implementation process of the present invention, find, at the incipient 1-50h of electrorefining process, after electrolyzer is pressed and be there will be certain decline phenomenon, this phenomenon to derive from anode lead progressively to dissolve, its surface becomes coarse, causes actual real current density to decrease.Similarly, also there is thickening of stereotype and process of growth in the lead of galvanic deposit negative electrode, also causes the real current density of negative electrode to decrease, and these two factors are pressed electrolyzer can be low between 0.077-0.095V.Along with proceeding of electrorefining process, because anode surface accumulates the mud shape metal cladding of more indissolubles gradually, the rising that causes electrolyzer to be pressed.Press and be elevated to 0.2-0.4V when above when electrolyzer, now show that the lead bullion in anode almost dissolves completely, the anode sludge of the lead bullion anode scrap of residual minute quantity and electrolytic process formation only in anode.Stop electrolysis, and take out the content in galvanic deposit lead electrode, lead bullion anode scrap and anode thereof, electrorefining end of processing.Electrolysis obtains cathode electrodeposition lead and carries out melting operation, after casting, obtains pure lead pig.The anode sludge can be used as the important source material of rare metal simultaneously, enters corresponding refinement operation.
In sum, method of the present invention has following features:
(1) in implementation process of the present invention, perchloric acid-lead perchlorate solution of high density of the present invention, has increased substantially dissolving power and the specific conductivity of solution, thereby provides precondition for the Direct Electrolysis refined lead that improves low-purity lead bullion;
(2) in electrorefining process of the present invention, the present invention utilizes 3 kinds of novel additives to suppress respectively perchloric acid in cathodic reduction, promote lead bullion to dissolve and control plumbous electrodeposition process, the use of these three kinds of new additives, effectively overcome perchloric acid from easily generating a difficult problem for dendrite arm in cathodic reduction and lead in perchloric acid medium, thereby can obtain purity up to more than 99.99% fine and close galvanic deposit lead.
(3) the present invention adopts the new texture lead bullion anode with space in electrolytic process, thereby realize synchronously dissolve-synchronous electric of plumbous anode deposition process, this new anode and method thereof are the interpole gap significantly reducing between anode and negative electrode, theoretical basis is provided, thereby this ultrashort interpole gap can significantly reduce the resistance of solution self, obtain lower electrolysis energy consumption.
(4) the present invention adopts perchloric acid-lead perchlorate solution of non-volatility, can greatly eliminate the poisonous acid mist problem of existing refining plant because adopting silicofluoric acid medium to produce, thereby increases substantially labor's Production environment quality.
(5) the present invention adopts the anode that novel acid resisting material is made, and has almost realized the whole dissolvings of high-level efficiency of lead bullion and the high efficiente callback of the anode sludge completely.This employing anode is realized whole dissolution mode of lead bullion, has significantly changed on the one hand and in existing electrorefining technique, only can dissolve the shortcoming of half anode, thereby increased substantially production efficiency.Effectively reduce on the other hand the pollution of the anode sludge to galvanic deposit lead electrode, thereby provide favourable condition for obtaining more highly purified galvanic deposit lead.
(6) the present invention proposes the electrolysis mode stage by stage that adopts electrokinetic potential scanning and continuous current combination, optimize electrolytic process curve, thereby can obtain lower electrolysis energy consumption in electrolytic process.
Great many of experiments shows, this new plumbous electrorefining technique, and the present three aspects: advantage of final body:
(1) less energy-consumption.
The present invention (200-300A/m under with the identical current density of existing industrial electrolysis
2) in batch experiment, the electrolyzer that can obtain the low 0.07-0.13V of reaching is pressed, the electrolyzer of directly saving more than 0.3-0.4V than the existing Bai Zifa extensively adopting is both at home and abroad pressed, more than realizing the refining process economize on electricity 60-80% of lead per ton, this can save every year 3200-3600 ten thousand degree electricity for the Qian Ye company of 400,000 tons of annual outputs.
(2) high efficiency
Novel process adopts high-solvency electrolytic solution, has directly realized plumbous synchronous dissolving-electrodeposition process with space anode and three kinds of modes of anode, reducing energy consumption simultaneously, the residual anode ratio of anode is reduced to 1-10% from existing 40-60%, when this significantly reduces the plumbous production cycle, improve the production efficiency of plumbous refining
(3) high rare metal recovery amount
The analysis experiments such as ICP show, novel process can be saved existing 1-2 road pyrogenic process decopper(ing) preliminary refining operation, thereby significantly reduce the rare metal loss of pyrogenic process preliminary refining process, wherein the yield of noble silver can be increased to from the 1100-2000 of existing lead per ton gram the 2200-5600 gram of the inventive method.
Thereby the present invention is as a kind of novel electrolytic lead refining technology, it not only can promote the energy-saving and emission-reduction of plumbous industry, and can significantly promote the rate of recovery of precious metal, thereby creates higher economic benefit.
Embodiment
Illustrative embodiments hereinafter will be described in more detail.Described but not be limited.
Embodiment 1
(1) get the lead bullion (its composition is in table 1) of selling on market, wherein lead content is about 98%.By the melting of 1kg lead bullion and cast the streaky lead bullion anode of surface band, be of a size of 8*10*1.25 (wide * is high, and * is thick) cm
3, the apparent density of its anode is 10.0g/cm
3, anode packs in the anode that polyvinyl chloride diaphragm material makes simultaneously, and bag is thick is 0.3mm.
(2) adopt and be of a size of 8*10*0.05 (wide * is high, and * is thick) cm
3the plumbous negative electrode starting sheet of making of galvanic deposit, the interpole gap of controlling anode and negative electrode is 2.0-2.2cm, and they are placed in electrolyzer abreast;
(3) configuration concentration is 2.0mol/L HClO
4pb (ClO with 0.33mol/L
4)
2mixing solutions 300ml, then adds additive, makes the boric acid that contains 0.55g/L in electrolytic solution, 0.3g/L Mono Chloro Acetic Acid, and 0.2g/L acetic acid, after 2.0g/L gelatine and 2.0g/L sodium lignosulfonate and make electrolyte temperature progressively be elevated to 55 DEG C, and is stabilized in this temperature;
(4) (3) process is obtained to mixed electrolytic solution and be injected in electrolyzer, be stabilized in after 55 DEG C until electrolyte temperature, the beginning constant-current electrolysis of connecting with the mains.The current density of controlling on lead bullion anode and negative electrode starting sheet is 350A/m
2.Now the electrolyzer of electrorefining process is pressed and is generally between 0.091-0.133V.Along with the carrying out of anode electrolysis process in leaching, its surface has accumulated the anode sludge of more indissolubles, has hindered the carrying out of anodic stripping, the rising that causes electrolyzer to be pressed.Press and be elevated to 0.25V when above when electrolyzer, now we stop electrorefining, the content in taking-up galvanic deposit lead electrode, lead bullion anode scrap and anode thereof, electrorefining end of processing.Electrolysis is obtained to cathode electrodeposition lead to be carried out obtaining pure lead pig after melting and casting.The anode sludge in anode is used for refining rare metal.Because there is slight crystal protrusion phenomenon on the plumbous surface of electrolytic deposition, and slight void between crystal, its apparent density is 10.1g/cm
3, the mean pole spacing between two electrodes remains unchanged substantially.
Through ICP quantitative analysis, the metals content impurity in this lead pig is as shown in table 1.
Table 1
Contrast lead pig GB/T469-2005 national standard, this lead pig has reached the standard of national Pb99.994.As calculated, the power consumption of electrolytic process ton lead is 27.9 degree electricity.
Embodiment 2
(1) get the lead bullion (its composition is in table 2) of selling on market, wherein lead content is about 98%.By the melting of 1kg lead bullion and cast and be with streaky lead bullion anode, be of a size of 8*10*1.25 (wide * is high, and * is thick) cm
3, the apparent density of its anode is 10.0g/cm
3, anode packs in the anode that polycthylene grafted mould material makes simultaneously, and bag is thick is 0.05mm.
(2) adopt and be of a size of 8*10*0.05 (wide * is high, and * is thick) cm
3the plumbous negative electrode starting sheet of making of galvanic deposit, the interpole gap of controlling anode and negative electrode is 2.0-2.2cm, and they are placed in electrolyzer abreast;
(3) configuration concentration is 2.2mol/L HClO
4pb (ClO with 0.32mol/L
4)
2mixing solutions 300ml, then adds additive, makes the tripoly phosphate sodium STPP that contains 0.05g/L in electrolytic solution, 0.2g/L Mono Chloro Acetic Acid, 0.2g/L acetic acid, after 1.5g/L gelatine and 2.5g/L sodium lignosulfonate and make electrolyte temperature progressively be elevated to 50 DEG C, and is stabilized in this temperature;
(4) (3) process is obtained to mixed electrolytic solution and be injected in electrolyzer, stablize after 50 DEG C until electrolyte temperature, the beginning constant-current electrolysis of connecting with the mains.The current density of controlling on lead bullion anode and negative electrode starting sheet is 300A/m
2.Now the electrolyzer of electrorefining process is pressed and is generally between 0.095-0.155V.Along with the carrying out of anode electrolysis process in leaching, its surface has accumulated the anode sludge of more indissolubles, has hindered the carrying out of anodic stripping, the rising that causes electrolyzer to be pressed.Press and be elevated to 0.25V when above when electrolyzer, now we stop electrorefining, the content in taking-up galvanic deposit lead electrode, lead bullion anode scrap and anode thereof, electrorefining end of processing.Electrolysis is obtained to cathode electrodeposition lead to be carried out obtaining pure lead pig after melting and casting.The anode sludge in anode is used for refining rare metal.Because there is slight crystal protrusion phenomenon on the plumbous surface of electrolytic deposition, and slight void between crystal, its apparent density is 10.1g/cm
3, the mean pole spacing between two electrodes remains unchanged substantially.
Through ICP quantitative analysis, the metals content impurity in this lead pig is as shown in table 2.
Table 2
Contrast lead pig GB/T469-2005 national standard, this lead pig has reached the standard of national Pb99.994.As calculated, the power consumption of electrolytic process ton lead is 28.6 degree electricity.
Embodiment 3
(1) get the lead bullion (its composition is in table 3) of selling on market, wherein lead content is about 98%.By the melting of 1kg lead bullion and cast and be with streaky lead bullion anode, be of a size of 8*10*1.15 (wide * is high, and * is thick) cm
3, the apparent density of its anode is 10.9g/cm
3, anode packs in the anode that polycthylene grafted mould material makes simultaneously, and bag is thick is 0.05mm.
(2) adopt and be of a size of 8*10*0.05 (wide * is high, and * is thick) cm
3the plumbous negative electrode starting sheet of making of galvanic deposit, the interpole gap of controlling anode and negative electrode is 0.9-1.1cm, and they are placed in electrolyzer abreast;
(3) configuration concentration is 2.2mol/L HClO
4pb (ClO with 0.3mol/L
4)
2mixing solutions 300ml, then adds additive, makes the trisodium phosphate that contains 0.10g/L in electrolytic solution, 0.2g/L Mono Chloro Acetic Acid, 0.2g/L acetic acid, after 2.0g/L gelatine and 2.5g/L sodium lignosulfonate and make electrolyte temperature progressively be elevated to 40 DEG C, and is stabilized in this temperature;
(4) (3) process is obtained to mixed electrolytic solution and be injected in electrolyzer, stablize after 40 DEG C until electrolyte temperature, the beginning constant-current electrolysis of connecting with the mains.The current density of controlling on lead bullion anode and negative electrode starting sheet is 100A/m
2.Now the electrolyzer of electrorefining process is pressed and is generally between 0.075-0.135V.Along with the carrying out of anode electrolysis process in leaching, its surface has accumulated the anode sludge of more indissolubles, has hindered the carrying out of anodic stripping, the rising that causes electrolyzer to be pressed.Press and be elevated to 0.30V when above when electrolyzer, now stop electrorefining, the content in taking-up galvanic deposit lead electrode, lead bullion anode scrap and anode thereof, electrorefining end of processing.Electrolysis is obtained to cathode electrodeposition lead to be carried out obtaining pure lead pig after melting and casting.The anode sludge in anode is used for refining rare metal.Only there is very small crystal protrusion phenomenon on the plumbous surface of this electrolytic deposition, the comparatively smooth densification of entirety, and its apparent density is 10.9g/cm
3, the mean pole spacing kept stable between two electrodes.
Through ICP quantitative analysis, the metals content impurity in this lead pig is as shown in table 3.
Table 3
Contrast lead pig GB/T469-2005 national standard, this lead pig has reached the standard of national Pb99.994.As calculated, the power consumption of electrolytic process ton lead is 20.9 degree electricity.
Embodiment 4
(1) get the lead bullion (its composition is same in table 4) of selling on market, wherein lead content is about 98%.By the melting of 1kg lead bullion and cast and be with streaky lead bullion anode, be of a size of 8*10*1.23 (wide * is high, and * is thick) cm
3, the apparent density of its anode is 10.2g/cm
3, anode packs in the anode that polycthylene grafted mould material makes simultaneously, and bag is thick is 0.05mm.
(2) adopt and be of a size of 8*10*0.05 (wide * is high, and * is thick) cm
3the plumbous negative electrode starting sheet of making of galvanic deposit, the interpole gap of controlling anode and negative electrode is 2.0-2.2cm, and they are placed in electrolyzer abreast;
(3) configuration concentration is 2.5mol/L HClO
4pb (ClO with 0.3mol/L
4)
2mixing solutions 300ml, then add additive, make the boric acid that contains 0.25g/L in electrolytic solution, 0.2g/L Mono Chloro Acetic Acid, 0.2g/L acetic acid, after 0.02g/L naphthols and 2.5g/L sodium lignosulfonate and make electrolyte temperature progressively be elevated to 63 DEG C, and is stabilized in this temperature, and make electrolyte temperature progressively be elevated to 63 DEG C, and be stabilized in this temperature.
(4) (3) process is obtained to mixed electrolytic solution and be injected in electrolyzer, stablize after 63 DEG C until electrolyte temperature, the beginning constant-current electrolysis of connecting with the mains.The current density of controlling on lead bullion anode and negative electrode starting sheet is 600A/m
2.Now the electrolyzer of electrorefining process is pressed and is generally between 0.133-0.189V.Along with the carrying out of anode electrolysis process in leaching, its surface has accumulated the anode sludge of more indissolubles, has hindered the carrying out of anodic stripping, the rising that causes electrolyzer to be pressed.Press and be elevated to 0.30V when above when electrolyzer, now stop electrorefining, the content in taking-up galvanic deposit lead electrode, lead bullion anode scrap and anode thereof, electrorefining end of processing.Electrolysis is obtained to cathode electrodeposition lead to be carried out obtaining pure lead pig after melting and casting.The anode sludge in anode is used for refining rare metal.Because there is small crystal protrusion phenomenon on the plumbous surface of electrolytic deposition, add the slight void of the plumbous intergranule of substrates, its apparent density is 10.2g/cm
3, the mean pole spacing kept stable between two electrodes.
Through ICP quantitative analysis, the metals content impurity in this lead pig is as shown in table 4.
Table 4
Contrast lead pig GB/T469-2005 national standard, this lead pig has reached the standard of national Pb99.994.As calculated, the power consumption of electrolytic process ton lead is 35.9 degree electricity.
Claims (8)
1. the direct electrolytic smelting method of lead bullion, it is characterized in that, pyrometallurgical smelting to be obtained to lead bullion be cast as lead bullion anode jacket in anode, in the perchloric acid-lead perchlorate electrolysis of solutions liquid that contains additive, carry out electrolysis by the plumbous galvanic deposit in anode to negative electrode, thereby obtain respectively highly purified electrolytic lead and the anode sludge at negative electrode and anode; Additive refers to the mixture that suppresses perchloric acid cathodic reduction additive 1, promotion lead bullion anode dissolution additive 2 and be used in perchloric acid medium's galvanic deposit additive 3; Additive 1 refers to a kind of or two kinds of mixtures in tripoly phosphate sodium STPP, trisodium phosphate, boric acid or 3-methoxybenzoic acid; Additive 2 refers to the mixture of Monochloro Acetic Acid and acetic acid; The plumbous additive 3 of galvanic deposit refers to a kind of or two kinds of mixtures in naphthols, gelatine, sodium lignosulfonate or tonka bean camphor.
2. according to the method for claim 1, it is characterized in that, lead bullion anode refers to the lead bullion anode that contains a fixed gap, and its apparent density is controlled at 9.9-11.0g/cm
3between, after electrolysis completes, the anode sludge is stayed in anode, and the anode sludge separating in anode obtains rare metal contained in lead bullion.
3. according to the method for claim 1, it is characterized in that, anode is to adopt a kind of or two kinds of fibers in polyvinyl alcohol fiber, viscose fiber, polyvinyl chloride barrier film, polypropylene or polycthylene grafted mould material to be prepared from, and its gauge control is at 0.03-0.8mm.
4. according to the method for claim 1, it is characterized in that, additive 1 refers to a kind of or two kinds of mixtures in tripoly phosphate sodium STPP, trisodium phosphate, boric acid or 3-methoxybenzoic acid, and their separately effective concentration is respectively 0.01-2.5g/L, 0.05-6.0g/L, 0.01-10.0g/L and 0.01-5.0g/L.
5. according to the method for claim 1, it is characterized in that, additive 2 refers to the mixture of Monochloro Acetic Acid and acetic acid, and their effective concentration is respectively 0.02-10g/L and 0.01-5.0g/L.
6. according to the method for claim 1, it is characterized in that, the plumbous additive 3 of galvanic deposit refers to a kind of or two kinds of mixtures in naphthols, gelatine, sodium lignosulfonate or tonka bean camphor, wherein the concentration of above-mentioned four kinds of additive materials corresponding 0.002-0.035g/L, 0.05-5.0g/L, 0.05-2.5g/L and 0.01-0.5g/L respectively.
7. according to the method for claim 1, it is characterized in that, the feature of described perchloric acid-lead perchlorate electrolytic solution is that the concentration of perchloric acid is 0.3-3.5mol/L, and the concentration of lead perchlorate is 0.05-1.0mol/L, and the working temperature of electrolytic solution is 0-75 DEG C.
8. according to the either method of claims 1-7, it is characterized in that, described electrolysis, different temperature is selected different constant current density, and when the temperature of electrolytic solution is during in 30-45 DEG C, constant-current electrolysis adopts 20-300A/m
2current density be advisable; When electrolyte temperature is during in 45-60 DEG C, constant-current electrolysis adopts 300-600A/m
2current density; When electrolyte temperature is during in 60-75 DEG C, constant-current electrolysis adopts 600-1200A/m
2current density.
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| CN103695967A (en) * | 2013-12-31 | 2014-04-02 | 湖南省桂阳银星有色冶炼有限公司 | Method for resisting lead ion depletion of lead electrolyte |
| CN104562093A (en) * | 2014-12-22 | 2015-04-29 | 芜湖金龙模具锻造有限责任公司 | Method for preparing cathode used in refining of lead bullion |
| CN108585126B (en) * | 2018-04-03 | 2021-07-06 | 广东工业大学 | Lead peroxide electrode and preparation method and application thereof |
| CN108950600B (en) * | 2018-07-12 | 2019-09-13 | 益阳生力材料科技股份有限公司 | A kind of electrolyte and electrolytic method of lead bullion electrorefining |
| CN110373686A (en) * | 2019-07-24 | 2019-10-25 | 中国环境科学研究院 | A kind of potroom groove face acid mist source cut down clean preparation method and system |
| CN110791802A (en) * | 2019-10-21 | 2020-02-14 | 北京曙光航空电气有限责任公司 | Electrochemical treatment method based on polar plate sheath |
| CN113293409B (en) * | 2021-05-28 | 2022-06-24 | 中南大学 | Method for preparing compact and flat bismuth metal through electrolysis |
| CN115058603A (en) * | 2022-07-26 | 2022-09-16 | 梧州华锡环保科技有限公司 | Anode mud removing device for high-antimony lead anode scrap and using method thereof |
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