A kind of method of utilizing the electrolytic zinc acid leaching slag ammonia process to produce high-purity nm zinc oxide
Technical field
The present invention relates to a kind of production method of zinc oxide, particularly a kind of production method of high-purity nm zinc oxide.
Background technology
Zinc hydrometallurgy mainly adopts the production technique of roasting-leaching-electrolysis at present, zinc content is counted in mass ratio and is generally 6-9% in the electrolytic zinc acid leaching slag of discharging, what have can reach 20%, and material phase analysis and X diffraction analysis that acid leaching residue is done show that zinc is mainly with ZnFe in the leached mud
2O
4,The zinc silicate form exists, simultaneously, the mass content 6-12% of sulphur, wherein the mass content of sulfate radical is 15-30%, ore deposit, various places calcium, magnesium salts content difference also contain Cu simultaneously
2+, Pb
2+, Cd
2+, Ni
2+, Hg
2+, As
3+Plasma, its roughly mass content be about: copper 1%, plumbous 0.8%, iron 4%, silicon 3%, arsenic 0.3%, silver 0.003%, calcium 12%, magnesium 3%.In order to reclaim these zinc, present treatment process has two kinds of pyrogenic process and wet methods at present, and pyrogenic process is rotary kiln evaporation method (waelz process) and fuming furnace volatilization method, is the Chinese patent application of CN101886180 such as publication number.Wet method has hot acid to leach or high-temperature pressurizing leaches.The pyrogenic attack technical process is long, and the maintenance of equipment amount is large, and investment is high, and Working environment is relatively poor, needs to consume a large amount of coal-fired or metallurgical coking coal, and benefit is low, and environmental pollution is large.Therefore usually leach with hot acid or high pressure leaches, these methods still existent defect are: 1. consume a large amount of acid, 2. the pressure of deironing is large, needs to consume more reagent, 3. high-temperature high-pressure apparatus seriously corroded, and the complicated investment of equipment is larger; 4. running cost is high, deficiency in economic performance.5. last slag of discharging is acid slag, brings new pollution to environment, have to take solidify ﹠ bury, not only contaminate environment, and waste resource.
Optimal method is that the selectivity of carrying out zinc leaches, and zinc is entered in the solution, and zinc obtains valuable recycling
High-purity zinc oxide refers to that generally the oxidation Zn-content is at the zinc oxide product more than 99.7%, high-purity zinc oxide is the indispensable a kind of high-tech raw material of modern industry, of many uses, be mainly used in the tens of kinds of industry and enterprises such as glass, feed, pottery, dyestuff, paint, papermaking, rubber, agricultural chemicals, oil refining, zinc-plated, special steel material, alloy, science and techniques of defence, no matter be glass, papermaking, or rubber, oil refining etc. all are in great demand to zinc oxide, and purity requirement is very high.
Nano zine oxide (ZnO) be a kind of particle diameter between 1-100 nm, novel high function fine inorganic product geared to the 21st century, show many special character, such as non-migrating, fluorescence, piezoelectricity, absorption and scatters ultraviolet ability etc., utilize it in the marvellous performance of the aspects such as light, electricity, magnetic, sensitivity, can make gas sensor, fluor, varistor, UV-preventing material, image recording material, piezoelectric, voltage dependent resistor, effective catalyst, magneticsubstance and plastics film etc.
Produce at present the method for nano zine oxide, mainly contain chemical precipitation method, sol-gel method, microemulsion method and hydrothermal synthesis method etc.But the raw material that adopts all is that zinc content is at the zinc baking sand more than 50% or pure zinc salt etc.
Ammonia process is a kind of common method of preparation zinc oxide, the general step of ammonia process (ammonia-carbon ammonium associating lixiviation process is produced zinc oxide) comprising at present: ammonia-carbon ammonium is leach liquor, material containing zinc is leached, and the zinc ammino closes liquid and makes zinc oxide product through purification, ammonia still process crystallization, drying and calcining.
This traditional ammonia process prepares the processing that zinc oxide never is applied to electrolytic zinc acid leaching slag, and major cause is:
1) a large amount of calcium sulfate parcel is arranged in the electrolytic zinc acid leaching slag and so that zinc wherein leaches difficulty, the rate of recovery is low
2) contain the sulfate radical of 15-30% in the electrolytic zinc acid leaching slag, a large amount of ammonia are converted into ammonium sulfate, and the ammonia consumption is high.
3) the zinc ammonia complex liquid direct purification after conventional method will leach is removed heavy metal with zinc replacement as last, owing to have a large amount of free ammonias in the solution, impurity complexing power is strong, produce back molten phenomenon easily, affect decontamination effect improving, finally affect the purity of zinc oxide product
4) owing to have a large amount of ammonium sulfate in the liquid, in the ammonia still process process, will separate out part of sulfuric acid zinc ammonium double salt, finally affect zinc oxide purity.
Present published method for producing nanometer-zinc oxide by ammonia leaching technology all is lower temperature hydrolytic precipitation method as:
Chinese patent application numbers 92103230.7 has been announced a kind of improvement technology for the legal production zinc oxide of traditional ammino, with the zinc ammonia complex liquid thin up after purifying, make the hydrolysis of part zinc ammonia complex liquid, obtain zinc subcarbonate (zinc hydroxide is 2:1 with the ratio of zinc carbonate), then continue heating until the decomposition of zinc ammonia complex liquid is complete, obtain the nano zine oxide of 30-100nn through high-temperature calcination.
The following problem of this technical patent needs to solve:
After the hydrolysis, non-dissociated zinc ammonia complex liquid is in the thermal degradation process, and the new zinc subcarbonate that produces can in original nucleating surface continued growth, impel the crystal of former hydrolysis to grow up, cause easily zinc subcarbonate xln particle diameter inhomogeneous, make the finished product particle diameter wayward.
Increase the 4-10 water yield doubly, reduced the efficient of producing in the process, increase energy consumption, increase the rear end cost of water treatment.
Chinese patent application numbers 200610130477.7 has been announced a kind of improvement technology for the legal production zinc oxide of traditional ammino, with zinc ammonia complex liquid, mix with the hot water of 1:2-20 or the mother liquor of heat continuously, mother liquor is cycled to used in the hydrolysis of zinc ammonia complex liquid behind heat tracing, make the nano zine oxide of 10-50nn.
The following problem of this technical patent needs to solve:
Ammonia can not be separated fully after the mother liquor hydrolysis, and repeating to superpose does not reach the effect of hydrolysis, is zinc ammonia complex liquid the most at last and the mixing of zinc ammonia complex liquid.
More than two kinds of patents in fact all be to manage at low temperatures, utilize the Macrodilution of water to make the pH value of solution slight the change occur and hydrolysis crystallization acquisition part Nanocrystal, only actually relies on the slight change of pH value can only obtain few part hydrolysis (can find from zinc oxide) in the situation when zinc concentration is higher ammonia solvent is write music line chart.The efficient separated out of the zinc ammoniacal liquor of high density is high in fact, energy consumption is low, and the efficient that the zinc ammoniacal liquor of lower concentration is separated out is low, energy consumption is high, the people be the proportional that adds flood to produce nano zine oxide be feasible technically, but may not be feasible aspect economic benefit.
In addition, ammonia leaching process is produced zinc oxide at present, xln is high (first about 125 ℃ of the temperature that makes of zinc hydroxide decomposition of zinc subcarbonate decomposition temperature, about 300 ℃ of zinc carbonate), for obtaining high purity product, must guarantee sufficiently high decomposition temperature, the general control temperature just can make zinc subcarbonate decompose fully more than 500 ℃.Be 200610130477.7 Chinese patent application such as application number, calcining temperature is up to 550 ℃.High-temperature calcination has a strong impact on specific surface area and the activity thereof of zinc oxide, then has influence on its Application Areas.
In sum, for the processing of electrolytic zinc acid leaching slag, how in the material of low levels zinc, effectively to leach zinc wherein, and obtain the zinc oxide of high-purity Nano-class, need overcome simultaneously traditional pyrogenic process and the shortcoming of wet method, become the technical barrier that the industry needs to be resolved hurrily.
Summary of the invention
One of goal of the invention of the present invention is: for the problem of above-mentioned existence, the zinc in a kind of efficient recovery electrolytic zinc acid leaching slag is provided and prepares the method for high-purity nm zinc oxide.
The technical solution used in the present invention is such: a kind of method of utilizing the electrolytic zinc acid leaching slag ammonia process to produce high-purity nm zinc oxide may further comprise the steps:
Leach pending electrolytic zinc acid leaching slag, purification and impurity removal, ammonia still process crystallization and drying and calcining,
Before the pending electrolytic zinc acid leaching slag step of leaching, add white lime in the pending electrolytic zinc acid leaching slag and carry out admixture activation, the amount of the white lime that adds by weight, is the 1-5% of pending electrolytic zinc acid leaching slag;
Electrolytic zinc acid leaching slag after the activation is leached with ammoniacal liquor-ammonium fluid; Wherein, NH
3Volumetric molar concentration c (NH
3)=5-6mol/L, CO
3 2-Volumetric molar concentration c (CO
3 2-)=0.9-1.2 mol/L adds the 0.3-0.5kg Sodium Silicofluoride in ammoniacal liquor-ammonium fluid of every cubic metre;
Behind purification and impurity removal, carry out refinement treatment, method is: in the liquid after purification and impurity removal is processed, add ammonium phosphate and tensio-active agent, add-on is 1-3kg ammonium phosphate, 10-50g tensio-active agent in every cubic metre of liquid after the purification and impurity removal processing;
Purification and impurity removal, ammonia still process crystallization and drying and calcining step all adopt present common ammonia process to prepare the processing parameter of zinc oxide.
The technology that the present invention at first prepares existing ammonia process zinc oxide is applied to the processing to electrolytic zinc acid leaching slag, simultaneously, on the technique basis of existing ammonia process, before ammonia soaks step, increased pre-treatment, be to add the step that white lime activates in the electrolytic zinc acid leaching slag, in leaching liquid, add an amount of Sodium Silicofluoride, in addition simultaneously, behind purification and impurity removal, increased the step of refinement treatment.
At first, obtain highly purified zinc oxide, need at first to guarantee that the zinc in the electrolytic zinc acid leaching slag can leach as much as possible, can improve so on the one hand the rate of recovery of zinc, on the other hand, zinc concentration is larger in leach liquor, and the impurity concentration relative proportion is just less, can guarantee to make more highly purified zinc oxide under equal processing condition.
Owing to contain a large amount of calcium sulfate (15-30%) in the electrolytic zinc acid leaching slag, the ultrafine particulates such as calcium sulfate play buffer action to leaching agent, cause acid environment to leach, so the present invention adopts ammonia process to leach, under ammonia-carbon ammonium associating liquid effect, calcium sulfate is converted into calcium carbonate and calcium hydroxide, in conversion process, thereby forms infiltration and the stripping that leaching agent is accelerated in the space; But calcium hydroxide also has certain sealing process to leaching, and in order to address this problem, the present inventor draws by great many of experiments: an amount of silicofluoric acid is received and can be abolished ultrafine particulate to containing zinc particle parcel, realizes ultrafine particulate layering come-up.
Simultaneously, the present inventor draws by great many of experiments: the adding of an amount of white lime, on the one hand can in and remaining sulfuric acid in the acid leaching residue; Can increase on the other hand the OH in the leaching environment
-, improve the degree of activation of ammonia and the leaching rate of zinc; Again on the one hand, OH
-Can make that the crystallization resultant is converted into zinc hydroxide by zinc carbonate in the subsequent step.
Secondly, obtain nano level zinc oxide, need to suppress growing up of crystal grain, the nano zine oxide that existing ammonia process production obtains why size and particle size distribution range is unsatisfactory, most important reason is constantly the growing up of crystal in treating processes, especially processes for the raw material of this low zinc content of electrolytic zinc acid leaching slag.In order to address the above problem, the present inventor is by great many of experiments, behind purification and impurity removal, increase the step of refinement treatment, in the solution after purification and impurity removal is processed, add an amount of ammonium phosphate and tensio-active agent, in conjunction with the growth of energy establishment xln under the high-speed stirring.
Wherein:
Chemical reaction in the reactivation process is:
Ca(OH)
2+CO
3 2-→CaCO
3↓+2OH
-
2NH
3·H
2O + CaSO
4 →Ca(OH)
2 ↓+(NH
4)
2SO
4
NH
4HCO
3+ NH
3·H
2O+ CaSO
4 →CaCO
3↓+(NH
4)
2SO
4+H
2O
Fe
3+ +3OH
- →Fe(OH)
3↓
Fe
2+ +2OH
- →Fe(OH)
2↓;
The chemical equation of leaching step is:
ZnO+nNH
3 +H
2O→[Zn(NH
3)n]
2++2OH
-
ZnFe
2O
4 +nNH
3+4H
2O→[Zn(NH
3)n]
2++2Fe(OH)
3 ↓+2OH
-
ZnFe
2O
4 +nNH
3+H
2O→[Zn(NH
3)n]
2++Fe
2O
3↓+2OH
-
ZnSiO
3+ nNH
3 +2NH
4HCO
3→[Zn(NH
3)n]CO
3+ SiO
2·H
2O+(NH
4)
2CO
3
Zn(OH)
2 +nNH
3 →[Zn(NH
3)n]
2++2OH
-
Zn+nNH
3 +2H
2O→[Zn(NH
3)n]
2++ H
2+ 2OH
-
ZnSO
4+nNH
3→[Zn(NH
3)n]
2++SO
4 2-
N=1~4 wherein;
The reaction that occurs in the purification and impurity removal process:
S
2O
8 2-+ Mn
2++ 2NH
3·H
2O + H
2O→ Mn O(OH)
2↓ + 2NH
4 ++2SO
4 2-+ 2H
+
S
2O
8 2-+2Fe
2+ +6H
2O →2SO
4 2-+ 2Fe(OH)
3↓+ 6H
+
AsO
4 3- + Fe
3- → FeAsO
4↓
AsO
3 3- + S
2O
8 2-+ H
2O → 2SO
4 2- + AsO
4 3-+ 2H
+
2H
3AsO
3 + 8Fe(OH)
3 → (Fe
2O
3)
4As
2O
3·5H
2O↓ +10H
2O
M
2++ S
2→ MS ↓ M represents Cu
2+, Pb
2+, Cd
2+, Ni
2+Hg
2+Plasma
As
3+ + S
2-→As
2S
3↓
Y
2++ Zn → Zn
2+Wherein Y representative of+Y: Cu
2+, Pb
2+, Cd
2+, Ni
2+Plasma;
The reaction formula of refinement treatment:
3[Zn(NH
3)n]
2++ 2(NH
4)
3PO
4+ 6OH
-→[Zn(NH
3)n]
3(PO
4)
2+ 6NH
3·H
2O
The reaction equation of ammonia still process step:
[Zn(NH
3)
i]
2++2OH
-= Zn(OH)
2↓+ iNH
3↑ i =1~4
A small amount of CO in the solution
3 2-Following hydrolysis reaction can occur:
[Zn(NH
3)
4]CO
3+H
2O→ZnCO
3·2Zn(OH)
2·H
2O↓+16NH
3↑;
The chemical equation of drying and calcining:
Zn(OH)
2→ZnO + H
2O↑
ZnCO
3·2Zn(OH)
2·H
2O → 3ZnO +3H
2O↑ +CO
2
As preferably: when leaching pending electrolytic zinc acid leaching slag, in ammoniacal liquor-ammonium fluid of every cubic metre, also be added with the tensio-active agent of 0.03-0.05kg.
The decreasing by surfactant surface energy, with the Sodium Silicofluoride mating reaction, the coating function that can abolish ultrafine particulate improves the leaching agent penetrating power, further improves the rate of recovery of zinc.
As preferably: the Dicyanodiamide that in ammoniacal liquor-ammonium fluid of every cubic metre, also is added with 0.5-1kg.
Dicyanodiamide can reduce ammonia emission in the leaching process as the ammonia stablizer, improves the leaching Working environment, reduces the loss of ammonia.
As preferably: when the pending electrolytic zinc acid leaching slag of leaching, adopt wet ball grinding, the activation leaching.
Utilize the wet ball grinding leaching, can destroy original crystalline network and carry out leaching while activating, thereby improve leaching efficiency.
As preferably: before the purification and impurity removal step, carry out pre-ammonia still process: leaching liquid is heated to 90-98 ℃ carries out ammonia still process, steam that ammonia concentration is 2.5-3.5mol/L to the liquid; Then add 2-4kg ammonium persulphate stirring oxidation by every cubic metre of leaching liquid and reach rough purification; During the ammonia still process crystallization, temperature is controlled in 105 ℃, and the speed per minute 300-500 that stirs in the ammonia still process equipment turns.
Increase pre-ammonia still process step, remove too much free ammonia on the one hand, the complex ability of impurity reduction makes foreign ion be easy to remove, and reduces to purify drug dosage, improves depuration quality; Can remove carbanions a large amount of in the solution on the other hand, be conducive to obtain zinc hydroxide nucleus precipitation when making the hydrolysis of complex liquid deamination, reduce the composition of zinc carbonate;
As preferably: in the ammonia still process crystallisation process, detect at any time solution zinc concentration in the ammonia still process container, when zinc content during at 1-1.5%, add sodium hydroxide solution in the container, add-on is that every cubic metre of solution adding massfraction is 30% sodium hydroxide solution 3-5 liter, when zinc content is lower than 0.3% in the solution, finish ammonia still process and (finish ammonia still process this moment, owing to contain a large amount of sulfate radicals in the solution, form stable ammonium salt, it is nonsensical to continue ammonia still process, and can produce zinc sulfate ammonium double salt precipitation, affects the nano zine oxide quality product).
In the ammonia still process later stage, when zinc concentration in the complex liquid is low, improve the pH value of liquid by adding sodium hydroxid, can make NH
4 +Ion transfers NH to
3Molecule reaches the effect of analysing fast ammonia, rapid crystallization formation nanometer zinc hydroxide nucleus.
As preferably: it is 5% sodium stearate solution 3-5L that every cubic metre of ammonia still process liquid adds mass percent.
In the ammonia still process process, add sodium stearate, make the Nanocrystal of generation be subject to the sealing parcel, no longer continue to grow up.
As preferably: add sodium sulphite and sink zinc in the crystallization raffinate, separation obtaining the zinc sulphide filter cake.Filtrate adds white lime again, mixed solution is stirred intensification ammonia still process transform, and temperature is not for being higher than 105 ℃, stirring velocity is 300-500 rev/min, and the ammonia of effusion is recycled by cooling, and ammonium sulfate is converted into the crystal of calcium sulfate body simultaneously, then carry out rinsing, drying, obtain the calcium sulfate powder.Turn waste into wealth, realize processing and recycling to water.
Two of purpose of the present invention provides a kind of high purity and highly active nano zine oxide, and the technical scheme that adopts is that the temperature of drying and calcining adopts 150-300 ℃.
Because technical scheme of the present invention, behind the ammonia still process crystallisation step, what obtain mainly is zinc hydroxide, the decomposition temperature of zinc hydroxide is lower than zinc subcarbonate, adopt 250-350 ℃ temperature to calcine, can obtain purity 99.7% and above zinc oxide, because the nucleus of zinc hydroxide is less than zinc subcarbonate, particle diameter is 10-30nm so finally can obtain being evenly distributed, and specific surface area 〉=100m
2The high-quality nanometer Zinc oxide powder that/g is above.
In sum, adopt technique scheme, ammonia process is applied to processing to the electrolysis acid leaching residue, and existing ammonia process carried out technological improvement, before leaching, increase activation step and when leaching, added Sodium Silicofluoride, tensio-active agent and Dicyanodiamide, electrolytic zinc acid leaching slag has reached efficient leaching on the one hand, and subsequent handling increases pre-ammonia still process and adds the resistive agent to suppress the growth of crystal in the ammonia still process process, obtains the little and uniform nanometer zinc oxide precursor of particle diameter of particle diameter; On the other hand, the lower calcining temperature of this preferred employing can obtain the high-purity nm zinc oxide (purity can reach 99.7%) than bigger serface, has very high practical value and economic worth; In addition, treatment process energy consumption of the present invention is low, efficient is high.There are valency and harmful heavy metal all to be leached utilization and clean through washing in the electrolytic zinc acid leaching slag.Obtain soaking slag end and become general solid refuse by the electrolytic zinc acid leaching slag as high-risk waste, reached the reasonable utilization of economic environmental protection and renewable resource.
Innovative point of the present invention mainly contains: ⑴ increases pre-ammonia still process to be processed, and drives first too much free ammonia away, reaches the purpose of rapid crystallization when ammonia still process; ⑵ in the ammonia still process process, when ammonia concentration in the zinc ammonia complex liquid is low, improve the pH value of liquid by adding sodium hydroxid, reach the purpose of analysing fast ammonia; ⑶ add tensio-active agent (such as SDS), ammonium phosphate in zinc ammonia complex liquid, the ammonium sulfate of having by oneself in the binding soln can effectively be controlled the growth of nano zine oxide nucleus; ⑷ utilize the power of steam to realize high-speed stirring, the crystallization of control nano zine oxide;
Embodiment
Below the present invention is described in detail.
In order to make purpose of the present invention, technical scheme and advantage clearer, below in conjunction with embodiment, the present invention is further elaborated.Should be appreciated that specific embodiment described herein only in order to explain the present invention, is not intended to limit the present invention.
Embodiment 1
A kind of method of utilizing the electrolytic zinc acid leaching slag ammonia process to produce high-purity nano zinc oxide may further comprise the steps successively:
(1) activation: get 500 gram electrolytic zinc acid leaching slags (wherein, by quality ratio, containing zinc 8.6%, copper 1.03%, calcium sulfate 32%, cadmium 0.05%, arsenic 0.03%), add 25 gram white limes and activate, soak time is 36 hours;
(2) leaching: produce the 1500ml ammonia leaching solution, wherein NH
3Concentration is 6mol/L, CO
3 2-Concentration is 1mol/L, in ammoniacal liquor-ammonium fluid of every cubic metre, add the 0.3kg Sodium Silicofluoride, electrolytic zinc acid leaching slag after the activation is joined and carries out three sections leachings in the above-mentioned ammonia leaching solution, each section leaching time is 2 hours, after the solid-liquid separation, zinc 38.9 grams (zinc recovery 90.5%) in the gained zinc ammonia complex liquid, sulfate radical 41.92 grams in the zinc ammonia complex liquid;
(3) purification and impurity removal: add 0.5 gram sodium sulphite at zinc ammonia complex liquid, stir after 2 hours and filter, add 0.2 gram potassium permanganate, stir after 2 hours and filter;
(4) refining: as in the liquid after purification and impurity removal is processed, to add 2kg ammonium phosphate, 30g surfactant SDS in the liquid after every cubic metre of purification and impurity removal is processed;
(5) ammonia still process crystallization: the zinc ammonia complex liquid after the refinement treatment is filtered post-heating ammonia still process, and ammonia distiller stirring velocity per minute 600 turns, and treats to stop when the zinc oxide mass content is 0.5% in the liquid ammonia still process; Then filter, obtain zinc hydroxide filter cake and filtrate;
(6) drying and calcining: the deionized water that the zinc hydroxide after the filtration adds respectively 200ml carries out three washings, add 0.05 gram sodium lauryl sulphate in the washing process in the first time, zinc hydroxide after the washing adds 150ml ethanol and washs, and the zinc hydroxide after the press filtration is put into retort furnace 250 degree calcinings 3 hours;
Made nano zine oxide median size 12.7nm(XRD live width method), the quality percentage composition is 99.7%, specific surface area 106m
2/ g.
Embodiment 2
A kind of method of utilizing the electrolytic zinc acid leaching slag ammonia process to produce high-purity nano zinc oxide may further comprise the steps successively:
(1) activation: get 500 gram acid leaching residues (zinc 7.6%, copper 0.83%, calcium sulfate 28%, cadmium 0.045%, arsenic 0.02%), add 5 gram white limes and activate, soak time is 40 hours;
(2) leaching: produce the 1500ml ammonia leaching solution, wherein NH
3Concentration is 5mol/L, CO
3 2-Concentration is 1.2mol/L, adds the 0.5kg Sodium Silicofluoride in ammoniacal liquor-ammonium fluid of every cubic metre, and also is added with the surfactant SDS of 0.04kg in ammoniacal liquor-ammonium fluid of every cubic metre; In ammoniacal liquor-ammonium fluid of every cubic metre, also be added with the Dicyanodiamide of 0.8kg; Electrolytic zinc acid leaching slag after the activation is joined and carries out three sections leachings in the above-mentioned ammonia leaching solution, ball milling in the time of leaching, each section leaching time is 2.5 hours, after the solid-liquid separation, zinc 34.9 grams (zinc recovery 91.8%) in the gained zinc ammonia complex liquid, sulfate radical 37.7 grams in the zinc ammonia complex liquid;
(3) pre-ammonia still process: leaching liquid is heated to 90 ℃, and every cubic metre of leaching liquid adds the 2kg ammonium persulfate, then carries out ammonia still process, steams that ammonia concentration is 3.5mol/L to the liquid;
(4) purification and impurity removal: add 0.6 gram sodium sulphite at zinc ammonia complex liquid, stir after 2 hours and filter, add 0.2 gram potassium permanganate, stir after 2 hours and filter;
(5) refining: as in the liquid after purification and impurity removal is processed, to add 1kg ammonium phosphate, 10g surfactant SDS in the liquid after every cubic metre of purification and impurity removal is processed;
(6) ammonia still process crystallization: the zinc ammonia complex liquid after the refinement treatment is filtered post-heating ammonia still process, and ammonia distiller stirring velocity per minute 900 turns, and temperature is controlled in 105 ℃, treats to stop when the zinc oxide mass content is 0.5% in the liquid ammonia still process; Then filter, obtain zinc hydroxide filter cake and filtrate;
(7) add sodium sulphite in the filtrate after the ammonia still process crystallization and react, separate obtaining solid zinc sulphide and liquid portion after the reaction; Add white lime at liquid portion, and stir and obtain mixed solution, in whipping process, add surfactant SDS; Mixed solution is carried out the ammonia still process crystallization, and Tc is 100 ℃, stirs in the ammonia still process process, and stirring velocity is 300 rev/mins, and the ammonia of separating out reclaims by cooling, and the calcium sulfate after the crystallization carries out rinsing, drying, obtains the calcium sulfate powder;
(8) drying and calcining: the deionized water that the zinc hydroxide filter cake after the filtration adds respectively 200ml carries out three washings, add 0.05 gram sodium lauryl sulphate in the washing process in the first time, zinc hydroxide after the washing adds 150ml ethanol and washs, and the zinc hydroxide after the press filtration is put into retort furnace 150 degree calcinings 3.5 hours;
Made nano zine oxide median size 11.5nm (XRD live width method), the quality percentage composition is 99.75%, specific surface area 110m
2/ g.
Embodiment 3
A kind of method of utilizing the electrolytic zinc acid leaching slag ammonia process to produce high-purity nano zinc oxide may further comprise the steps successively:
(1) activation: get 1500 gram acid leaching residues (zinc 9.0%, copper 0.80%, calcium sulfate 30%, cadmium 0.040%, arsenic 0.25%, silicon 3%, arsenic 0.3%, silver 0.003%, magnesium 3%), add 45 gram white limes and activate, soak time is 48 hours;
(2) leaching: produce the 1500ml ammonia leaching solution, wherein NH
3Concentration is 5.5mol/L, CO
3 2-Concentration is 0.9mol/L, adds the 0.5kg Sodium Silicofluoride in ammoniacal liquor-ammonium fluid of every cubic metre, and also is added with the surfactant SDS of 0.03kg in ammoniacal liquor-ammonium fluid of every cubic metre; In ammoniacal liquor-ammonium fluid of every cubic metre, also be added with the Dicyanodiamide of 1kg; Electrolytic zinc acid leaching slag after the activation is joined and carries out three sections leachings in the above-mentioned ammonia leaching solution, ball milling in the time of leaching, each section leaching time is 2.5 hours, after the solid-liquid separation, zinc 124.2 grams (zinc recovery 92.0%) in the gained zinc ammonia complex liquid, sulfate radical 165.0 grams in the zinc ammonia complex liquid;
(3) pre-ammonia still process: leaching liquid is heated to 98 ℃, and every cubic metre of leaching liquid adds the 1kg ammonium persulfate, then carries out ammonia still process, steams that ammonia concentration is 3.0mol/L to the liquid;
(4) purification and impurity removal: add 0.6 gram sodium sulphite at zinc ammonia complex liquid, stir after 2 hours and filter, add 0.2 gram potassium permanganate, stir after 2 hours and filter;
(5) refining: as in the liquid after purification and impurity removal is processed, to add 3kg ammonium phosphate, 50g surfactant SDS in the liquid after every cubic metre of purification and impurity removal is processed;
(6) ammonia still process crystallization: the zinc ammonia complex liquid after the refinement treatment is filtered post-heating ammonia still process, and ammonia distiller stirring velocity per minute 800 turns, and temperature is controlled in 105 ℃, treats to stop when the zinc oxide mass content is 0.5% in the liquid ammonia still process; Then filter, obtain zinc hydroxide filter cake and filtrate;
(7) add sodium sulphite in the filtrate after the ammonia still process crystallization and react, separate obtaining solid zinc sulphide and liquid portion after the reaction; Add white lime at liquid portion, and stir and obtain mixed solution, in whipping process, add tensio-active agent; Mixed solution is carried out the ammonia still process crystallization, and Tc is 102 ℃, stirs in the ammonia still process process, and stirring velocity is 500 rev/mins, and the ammonia of separating out reclaims by cooling, and the calcium sulfate after the crystallization carries out rinsing, drying, obtains the calcium sulfate powder;
(8) drying and calcining: the deionized water that the zinc hydroxide filter cake after the filtration adds respectively 200ml carries out three washings, add 0.05 gram sodium lauryl sulphate in the washing process in the first time, zinc hydroxide after the washing adds 150ml ethanol and washs, and the zinc hydroxide after the press filtration is put into retort furnace 250 degree calcinings 1.5 hours;
Made nano zine oxide median size 10.8nm (XRD live width method), the quality percentage composition is 99.80%, specific surface area 118m
2/ g.
Embodiment 4
120 tons of raw materials come from Yunnan Chihong Zinc ﹠ Germanium Co., Ltd.'s Huize and smelt the acid leaching residue that old factory many decades accumulates, zinc 11.2%, copper 0.91%, lead 1.3%, acid group 27.6%, cadmium 0.03% in the raw material.
(1) activation: add 2.5 tons of white limes in the above-mentioned raw materials and carry out admixture activation, soak time is 46 hours;
(2) leaching: produce 360m
3Ammonia leaching solution, wherein NH
3Concentration is 5.6mol/L, CO
3 2-Concentration is 1.1mol/L, in ammoniacal liquor-ammonium fluid of every cubic metre, add the 0.4kg Sodium Silicofluoride, electrolytic zinc acid leaching slag after the activation is joined and carries out three sections leachings in the above-mentioned ammonia leaching solution, and in ammoniacal liquor-ammonium fluid of every cubic metre, also be added with the surfactant SDS of 0.045kg; In ammoniacal liquor-ammonium fluid of every cubic metre, also be added with the Dicyanodiamide of 0.8kg; Ball milling in the time of leaching, each section leaching time is 2.6 hours, Gu after the solid-liquid separation, 12.23 tons on zinc (zinc recovery 91.0%) in the gained zinc ammonia complex liquid, sulfate radical is 13.7 tons in the zinc ammonia complex liquid;
Leached mud carries out scene sampling and leaching test through authoritative institution's " Yunnan Province's environmental monitoring junction centre " of Yunnan Province Environmental Protection Agency appointment, and waste meets the general solid waste standard of I class in " general industrial solid waste storage, disposal site pollute control criterion " (GB18599-2001);
(3) pre-ammonia still process: leaching liquid is heated to 96 ℃, and every cubic metre of leaching liquid adds the 3kg ammonium persulfate, then carries out ammonia still process, steams that ammonia concentration is 3.2mol/L to the liquid;
(4) purification and impurity removal: add 1.5kg sodium sulphite at every cubic metre of zinc ammonia complex liquid, stir after 2 hours and filter, every cubic metre of zinc ammonia complex liquid adds 0.3kg potassium permanganate, stirs after 2 hours and filters;
(5) refining: as in the liquid after purification and impurity removal is processed, to add 3kg ammonium phosphate, 50g surfactant SDS in the liquid after every cubic metre of purification and impurity removal is processed;
(6) ammonia still process crystallization: the zinc ammonia complex liquid after the refinement treatment is filtered post-heating ammonia still process, and ammonia distiller stirring velocity per minute 700 turns, and the control temperature is at 105 ℃; Treat to stop when the zinc oxide mass content is 0.5% in the liquid ammonia still process; Then filter, obtain zinc hydroxide filter cake and filtrate;
(7) add sodium sulphite in the filtrate after the ammonia still process crystallization and react, separate obtaining solid zinc sulphide and liquid portion after the reaction; Add white lime at liquid portion, and stir and obtain mixed solution, in whipping process, add tensio-active agent; Mixed solution is carried out the ammonia still process crystallization, and Tc is 103 ℃, stirs in the ammonia still process process, and stirring velocity is 400 rev/mins, and the ammonia of separating out reclaims by cooling, and the calcium sulfate after the crystallization carries out rinsing, drying, obtains the calcium sulfate powder;
(8) drying and calcining: drying and calcining: the filter cake after the filtration adds ion exchanged water by liquid-solid ratio 5:1 and carries out three washings, the sodium lauryl sulphate that in first time washing process, adds 1.25 grams/cubic meter, zinc hydroxide filter cake after the washing adds ethanol by liquid-solid ratio 1-5:1 and washs, and the zinc hydroxide after the press filtration is put into retort furnace 180 degree calcinings 3.5 hours;
Made nano zine oxide median size 12.6nm (XRD live width method), the quality percentage composition is 99.78%, specific surface area 116m
2/ g.