CN102925718A - Composite sodium salt for producing sodium stannate from cassiterite concentrate and application of composite sodium salt - Google Patents
Composite sodium salt for producing sodium stannate from cassiterite concentrate and application of composite sodium salt Download PDFInfo
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- CN102925718A CN102925718A CN2012104115931A CN201210411593A CN102925718A CN 102925718 A CN102925718 A CN 102925718A CN 2012104115931 A CN2012104115931 A CN 2012104115931A CN 201210411593 A CN201210411593 A CN 201210411593A CN 102925718 A CN102925718 A CN 102925718A
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Abstract
The invention discloses a composite sodium salt for producing sodium stannate from cassiterite concentrate and an application of the composite sodium salt. The composite sodium salt consists of 70%-90% of sodium carbonate, 5%-20% of sodium bicarbonate, 2.5%-5% of sodium borate and 2.5%-5% of sodium humate by mass. When the composite sodium salt is used, the composite sodium salt is ground to the particles with the size fraction of minus 0.1mm being no less than 90% by mass, the cassiterite concentrate of the fine fraction and the composite sodium salt are mixed according to the mass ratio of 1:(0.5-2), pelletized and dried, coke powder or anthracite is taken as a reducing agent, the mixture is calcined for 30 minutes-90minutes at the temperature of 800 DEG C-950 DEG C, and the cooled calcined product is ground, leached, filtered, purified, concentrated and crystallized, so that the sodium stannate product is obtained. The adopted composite sodium salt is reasonable in component, can be widely obtained, is low in price, is easy to obtain and does not cause pollution to the environment. With the composite sodium salt, the stable crystal structure of the cassiterite concentrate can be obviously damaged, and the composite sodium salt can be widely applied to various cassiterite concentrates so as to directly produce sodium stannate.
Description
Technical field
The present invention relates to the sodium salt that a kind of sodium stannate prepares usefulness, refer to especially a kind of compound sodium salt that directly prepares sodium stannate for the cassiterite concentrate, the invention still further relates to the application of compound sodium salt.
Background technology
Sodium stannate is to use one of tin Chemicals early, and its main application is for the alkaline tin plating of electroplating industry and alloy thereof (such as tin-zinc, tin-cadmium, tin-copper and tin-aluminium alloy etc.); In addition, also be used for fireproofing agent and the weighting agent of textile industry, dyestuffs industries can be used as mordant, also can be used for the additive of the industry such as glass, pottery.
In the traditional technology of preparation sodium stannate, usually take refined tin as raw material.Analyse method such as alkali, after mainly preparing wood shavings tin take refined tin as raw material, with the mashed prod of sodium hydroxide, SODIUMNITRATE and water synthetic sodium stannate in the thermal synthesis pot, obtain the sodium stannate aqueous solution by water logging, filtration more again, through purification and impurity removal, obtain containing the sodium stannate crystal of crystal water behind the condensing crystal.This technique once was used widely industrial, but this technical process is long, and energy consumption and production cost are all higher, and easily caused secondary pollution.
For solving the high problem of the expensive production cost that brings of refined tin, Chinese scholars was once developed alkali fusion method.The method mainly is to adopt cassiterite concentrate and sodium hydroxide to heat in electric furnace, obtains the sodium stannate melt under the high temperature, then the sodium stannate melt cooling is solidified rear fragmentation, boils in leaching pot, again with the filtrate condensing crystal, obtains thick sodium stannate crystal.Thick sodium stannate Crystal impurity content is higher, and after the remelting removal of impurities, secondary crystal obtains qualified product.This method need not expensive metallic tin, can be used for processing low-grade tin ore to obtain sodium stannate.But it is reagent that the method adopts NaOH, become melt under the high temperature after, have very strong corrodibility.Thereby, the method have the operation dangerous, cost is high, to shortcomings such as equipment material requirement harshnesses, be not used widely industrial.
Another kind of technique is comparatively ripe, the relatively simple sodium stannate preparation method of flow process is stripping method.The method be a kind of from the raw materials such as zinc-plated slag, zinc-plated steel scrap and tinplate waste material the method for reclaiming tin, in detin solution, make oxygenant with sodium hydroxide, SODIUMNITRATE or Sodium Nitrite or blending oxidizing agent is processed, condensing crystal behind the purification and impurity removal can obtain thick sodium stannate product.This method is only applicable to reclaim stanniferous waste residue, waste material, is not easy to the industrial production of stabilization.
Among the preparation method of traditional several sodium stannates, all adopted in sodium hydroxide, SODIUMNITRATE or the Sodium Nitrite one or more to mix sodium salts as additive, preparation process is to carry out under strong alkaline condition, sodium salt becomes melt under the high temperature, has extremely strong corrodibility, cause generating run dangerous, also the conversion unit material has been proposed harsh requirement.Simultaneously, exist a large amount of waste lyes to need to process in the preparation process, bring great pressure to environmental improvement.By consulting literatures is there are no adopting yellow soda ash, sodium bicarbonate, Sodium Tetraborate, sodium humate etc. directly to prepare the relevant report that sodium stannate is used sodium salt as the cassiterite concentrate.
In recent years, countries in the world are soaring year by year to the demand of sodium stannate.For various reasons, supply falls short of demand for present domestic sodium stannate, and the annual sodium stannate that needs from state's import some amounts such as Malaysia, Japan, Britain causes sodium stannate price rise steadily (70~750,000 yuan/tons).The production of accelerating domestic sodium stannate has great importance to the development of national economy.
The cost that exists in traditional sodium stannate preparation process is high, operation is dangerous, environmental pollution large in order to solve, equipment material is required the problems such as high, realizes directly, efficiently being prepared by the cassiterite concentrate purpose of sodium stannate, and the spy proposes the present invention.
Summary of the invention
First technical problem to be solved by this invention provides a kind of reasonable mixture ratio of components, wide material sources, cheap, environment is not produced harm, can effectively realize directly being prepared by the cassiterite concentrate the compound sodium salt that the cassiterite concentrate prepares sodium stannate that is used for of sodium stannate.
Second technical problem to be solved by this invention provides this and is used for the application that the cassiterite concentrate prepares the compound sodium salt of sodium stannate.
In order to solve above-mentioned first technical problem, the compound sodium salt for preparing sodium stannate for the cassiterite concentrate provided by the invention is comprised of according to following mass percent mixing yellow soda ash, sodium bicarbonate, Sodium Tetraborate and sodium humate:
Yellow soda ash 70%~90%, sodium bicarbonate 5%~20%, Sodium Tetraborate 2.5%~5%, sodium humate 2.5%~5%.
Preferably, be used for the compound sodium salt that the cassiterite concentrate prepares sodium stannate, formed according to following mass percent mixing by yellow soda ash, sodium bicarbonate, Sodium Tetraborate and sodium humate:
Yellow soda ash 75%~86%, sodium bicarbonate 8%~17%, Sodium Tetraborate 3%~4%, sodium humate 3%~4%.
Preferably, be used for the compound sodium salt that the cassiterite concentrate prepares sodium stannate, formed according to following mass percent mixing by yellow soda ash, sodium bicarbonate, Sodium Tetraborate and sodium humate:
Yellow soda ash 82%, sodium bicarbonate 12%, Sodium Tetraborate 3%, sodium humate 3%.
In order to solve above-mentioned second technical problem, the application that directly prepares the compound sodium salt of sodium stannate for the cassiterite concentrate provided by the invention, during use, at first compound sodium salt is ground to-the shared mass percent of 0.1mm grade is not less than 90%, with fine-graded cassiterite concentrate and compound sodium salt 1:(0.5~2 in mass ratio) mixing, pelletizing, after the drying, take coke powder or hard coal as reductive agent, be roasting 30min~90min under 800 ℃~950 ℃ conditions in temperature, cooled roasting product soaks through mill, filter, purify, condensing crystal is processed, obtain the sodium stannate product, the transformation efficiency of tin reaches more than 75%.
Adopt compound sodium salt and the application thereof that the cassiterite concentrate prepares sodium stannate that be used for of technique scheme, its know-why is summarized as follows:
Compound sodium salt can effectively destroy the stable crystalline structure of natural cassiterite, by controlling suitable weak reducing roasting condition, is converted into sodium stannate under the solid state reduction condition.Yellow soda ash in the compound sodium salt and sodium bicarbonate component can be decomposed into Na under the heat condition
2O and CO
2, Na
2The reactive behavior of O is high, easy and SnO
2Reaction generates sodium stannate; The Sodium Tetraborate fusing point is relatively low, generate a small amount of liquid phase under the heating condition, can significantly improve the reacting dynamics condition of cassiterite and yellow soda ash (or sodium bicarbonate) component, accelerate the carrying out of solid phase diffusion reaction, provide favourable material conditions for reducing maturing temperature and roasting time, raising tin transformation efficiency, thereby improve the transformation efficiency of tin.Under the weak reductive condition, SnO
2Reduction reaction can occur generate SnO or Sn, its stable crystalline network is at first weakened, and has promoted the carrying out of sodium stannate reaction.Sodium humate in the sodium salt additive has preferably cohesiveness, can effectively guarantee agglomerate intensity in the agglomeration process, makes agglomerate be difficult for producing efflorescence in heat-processed, and keeps complete shape, thereby whole calcination is carried out under solid conditions.
Advantage of the present invention mainly is:
Compound sodium salt wide material sources, cheap, be easy to obtain, and can effectively destroy the stable crystalline network of natural cassiterite, the transformation efficiency of tin reaches more than 75%.Compare with the sodium salt (sodium hydroxide, SODIUMNITRATE etc.) that traditional sodium stannate preparation is used, adopt compound sodium salt of the present invention, can not produce secondary pollution to environment, whole calcination is to carry out under solid conditions under the suitable roasting condition, to equipment material without particular requirement.Adopt compound sodium salt of the present invention, can be widely used in various cassiterite concentrate and directly prepare sodium stannate.
Embodiment
Below in conjunction with embodiment the present invention is described in further detail.
The SnO of cassiterite concentrate
2Grade is 83.8%.Before the test, at first cassiterite concentrate and compound sodium salt additive are ground to respectively-the shared mass percent of 0.1mm grade is not less than 90%.
Embodiment 1:
The mass percent of each component is in the compound sodium salt: yellow soda ash 70%, sodium bicarbonate 20%, Sodium Tetraborate 5%, sodium humate 5%.During use, after at first 1:0.5 mixes in mass ratio with cassiterite concentrate and compound sodium salt, pelletizing, drying, the employing coke powder is reductive agent, 950 ℃ of maturing temperatures, roasting time is 30min; Product of roasting obtains the sodium stannate product through ore grinding, leaching, filtration, purification and impurity removal, condensing crystal etc.The transformation efficiency of Sn is 75.2%.
Embodiment 2:
The mass percent of each component is in the compound sodium salt: yellow soda ash 75%, sodium bicarbonate 17%, Sodium Tetraborate 4%, sodium humate 4%.During use, after at first 1:0.9 mixes in mass ratio with cassiterite concentrate and compound sodium salt, pelletizing, drying, the employing coke powder is reductive agent, 910 ℃ of maturing temperatures, roasting time 45min; Product of roasting obtains the sodium stannate product through ore grinding, leaching, filtration, purification and impurity removal, condensing crystal etc.The transformation efficiency of Sn is 78.9%.
Embodiment 3:
The mass percent of each component is in the compound sodium salt: yellow soda ash 80%, sodium bicarbonate 14%, Sodium Tetraborate 3%, sodium humate 3%.During use, after at first 1:1.3 mixes in mass ratio with cassiterite concentrate and compound sodium salt, pelletizing, drying, the employing coke powder is reductive agent, 875 ℃ of maturing temperatures, roasting time is 60min; Product of roasting obtains the sodium stannate product through ore grinding, leaching, filtration, purification and impurity removal, condensing crystal etc.The transformation efficiency of Sn is 86.9%.
Embodiment 4:
The mass percent of each component is in the compound sodium salt: yellow soda ash 86%, sodium bicarbonate 8%, Sodium Tetraborate 2.5%, sodium humate 3.5%.During use, after at first 1:1.5 mixes in mass ratio with cassiterite concentrate and compound sodium salt, pelletizing, drying, the employing hard coal is reductive agent, 850 ℃ of maturing temperatures, roasting time is 35min; Product of roasting obtains the sodium stannate product through ore grinding, leaching, filtration, purification and impurity removal, condensing crystal etc.The transformation efficiency of Sn is 85.2%.
Embodiment 5:
The mass percent of each component is in the compound sodium salt: yellow soda ash 90%, sodium bicarbonate 5%, Sodium Tetraborate 2.5%, sodium humate 2.5%.During use, after at first 1:1.75 mixes in mass ratio with cassiterite concentrate and compound sodium salt, pelletizing, drying, the employing hard coal is reductive agent, 825 ℃ of maturing temperatures, roasting time is 75min; Product of roasting obtains the sodium stannate product through ore grinding, leaching, filtration, purification and impurity removal, condensing crystal etc.The transformation efficiency of Sn is 83.5%.
Embodiment 6:
The mass percent of each component is in the compound sodium salt: yellow soda ash 82%, sodium bicarbonate 12%, Sodium Tetraborate 3%, sodium humate 3%.During use, after at first 1:2 mixes in mass ratio with cassiterite concentrate and compound sodium salt, pelletizing, drying, the employing hard coal is reductive agent, 800 ℃ of maturing temperatures, roasting time is 90min; Product of roasting obtains the sodium stannate product through ore grinding, leaching, filtration, purification and impurity removal, condensing crystal etc.The transformation efficiency of Sn is 76.3%.
Claims (4)
1. one kind is used for the compound sodium salt that the cassiterite concentrate prepares sodium stannate, it is characterized in that: be comprised of according to following mass percent mixing yellow soda ash, sodium bicarbonate, Sodium Tetraborate and sodium humate:
Yellow soda ash 70%~90%, sodium bicarbonate 5%~20%, Sodium Tetraborate 2.5%~5%, sodium humate 2.5%~5%.
2. the compound sodium salt for preparing sodium stannate for the cassiterite concentrate according to claim 1 is characterized in that: mixed according to following mass percent by yellow soda ash, sodium bicarbonate, Sodium Tetraborate and sodium humate and form:
Yellow soda ash 75%~86%, sodium bicarbonate 8%~17%, Sodium Tetraborate 3%~4%, sodium humate 3%~4%.
3. the compound sodium salt for preparing sodium stannate for the cassiterite concentrate according to claim 1 is characterized in that: mixed according to following mass percent by yellow soda ash, sodium bicarbonate, Sodium Tetraborate and sodium humate and form:
Yellow soda ash 82%, sodium bicarbonate 12%, Sodium Tetraborate 3%, sodium humate 3%.
4. the application for preparing the compound sodium salt of sodium stannate for the cassiterite concentrate according to claim 1, it is characterized in that: during use, at first compound sodium salt is ground to-the shared mass percent of 0.1mm grade is not less than 90%, with fine-graded cassiterite concentrate and compound sodium salt in mass ratio after 1:0.5~2 mixings, pelletizing, the drying, take coke powder or hard coal as reductive agent, be roasting 30min~90min under 800 ℃~950 ℃ conditions in temperature, cooled roasting product through mill soak, filtration, purification, condensing crystal process, and obtains the sodium stannate product.
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Cited By (8)
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CN103408066A (en) * | 2013-08-30 | 2013-11-27 | 中南大学 | Method for preparing alkali earth metal stannate |
CN103466562A (en) * | 2013-08-30 | 2013-12-25 | 中南大学 | Preparation process of calcium stannate ceramic material precursor |
CN104152718A (en) * | 2014-07-21 | 2014-11-19 | 中南大学 | Method for synchronously separating tin and iron from tin-containing iron tailings |
CN104152671A (en) * | 2014-07-21 | 2014-11-19 | 中南大学 | Method for preparing iron ore concentrate for ironmaking from tin-containing iron ore |
CN104152717A (en) * | 2014-07-21 | 2014-11-19 | 中南大学 | Composite additive applied to metallic tin preparation process by reducing roasting of cassiterite ore concentrate, and method for preparing metallic tin |
CN105540651A (en) * | 2016-03-14 | 2016-05-04 | 中南大学 | Method for preparing spherical stannous oxide nanomaterial |
CN105603178A (en) * | 2016-03-14 | 2016-05-25 | 中南大学 | Method for preparing tin-iron coarse alloy powder from tin containing iron ore |
CN110065965A (en) * | 2019-04-25 | 2019-07-30 | 中南大学 | A kind of compound additive and method preparing sodium stannate for strengthening cassiterite concentrate soda roasting |
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CN103408066B (en) * | 2013-08-30 | 2015-07-15 | 中南大学 | Method for preparing alkali earth metal stannate |
CN103466562A (en) * | 2013-08-30 | 2013-12-25 | 中南大学 | Preparation process of calcium stannate ceramic material precursor |
CN103466562B (en) * | 2013-08-30 | 2015-11-25 | 中南大学 | A kind of preparation technology of calcium stannate ceramic material precursor |
CN103408066A (en) * | 2013-08-30 | 2013-11-27 | 中南大学 | Method for preparing alkali earth metal stannate |
CN104152718B (en) * | 2014-07-21 | 2015-10-21 | 中南大学 | A kind of method of stanniferous iron tailings separated in synchronization tin and iron |
CN104152717A (en) * | 2014-07-21 | 2014-11-19 | 中南大学 | Composite additive applied to metallic tin preparation process by reducing roasting of cassiterite ore concentrate, and method for preparing metallic tin |
CN104152671A (en) * | 2014-07-21 | 2014-11-19 | 中南大学 | Method for preparing iron ore concentrate for ironmaking from tin-containing iron ore |
CN104152717B (en) * | 2014-07-21 | 2015-11-25 | 中南大学 | The composite additive used in metallic tin process and the method preparing metallic tin are prepared in the reducing roasting of a kind of cassiterite concentrate |
CN104152718A (en) * | 2014-07-21 | 2014-11-19 | 中南大学 | Method for synchronously separating tin and iron from tin-containing iron tailings |
CN105540651A (en) * | 2016-03-14 | 2016-05-04 | 中南大学 | Method for preparing spherical stannous oxide nanomaterial |
CN105603178A (en) * | 2016-03-14 | 2016-05-25 | 中南大学 | Method for preparing tin-iron coarse alloy powder from tin containing iron ore |
CN105540651B (en) * | 2016-03-14 | 2017-05-10 | 中南大学 | Method for preparing spherical stannous oxide nanomaterial |
CN105603178B (en) * | 2016-03-14 | 2018-05-01 | 中南大学 | A kind of method that the thick alloyed powder of tin iron is prepared by Iron Ore Containing Tin |
CN110065965A (en) * | 2019-04-25 | 2019-07-30 | 中南大学 | A kind of compound additive and method preparing sodium stannate for strengthening cassiterite concentrate soda roasting |
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