Tin is a critical metal for various industries,making its recovery from low-grade cassiterite ores crucial.This study aimed to optimize the flotation recovery of cassiterite using multi-component collector systems.Sev...Tin is a critical metal for various industries,making its recovery from low-grade cassiterite ores crucial.This study aimed to optimize the flotation recovery of cassiterite using multi-component collector systems.Several collectors were initially selected through micro-flotation tests,leading to the identification of optimal proportions for a four-component collector system(SHA-OHA-SPA-DBIA in a 4:3:2:1 ratio).Molecular dynamics simulations and surface tension tests were used to investigate the micellar behavior of these collectors in aqueous solution.The adsorption characteristics were quantified using microcalorimetry,enabling the determination of collection entropy and changes in Gibbs free energy.The four-component collector system showed the highest entropy change and the most favorable Gibbs free energy,leading to a cassiterite recovery of above 90%at a concentration of 8.0×10^(5)mol/L.Various analytical techniques were employed to systematically characterize the adsorption mechanism.The findings revealed a positive correlation between the adsorption products formed by the multicomponent collectors on the cassiterite surface and the entropy changes.Industrial-scale testing of the high-entropy collector system produced a tin concentrate with an Sn grade of 6.17%and an Sn recovery of 82.43%,demonstrating its substantial potential for practical applications in cassiterite flotation.展开更多
In this study,the effect of Cu^(2+)on the cassiterite and calcite flotation using octanohydroxamic acid(OHA)as collector was investigated through flotation tests,solution reaction tests and calculation,zeta potential ...In this study,the effect of Cu^(2+)on the cassiterite and calcite flotation using octanohydroxamic acid(OHA)as collector was investigated through flotation tests,solution reaction tests and calculation,zeta potential measurements,XPS analysis and residual reagent concentration measurements.Results indicated that Cu^(2+)played an activation role on cassiterite flotation but a depression role on calcite flotation.The copper cations were adsorbed on the cassiterite surface by forming a Cu—O bond,and the pre-adsorbed copper cations and the OHA-Cu complexes promoted the adsorption of OHA on the cassiterite surface.Thus,cassiterite flotation was activated.The dissolved HCO_(3)-in the calcite pulp underwent a double hydrolysis reaction with copper cations(Cu^(2+),CuOH^(+),Cu_(2)(OH)_(2)^(2+)and Cu_(3)(OH)_(4)^(2+))to form CuCO_(3).Some copper cations were adsorbed on the calcite surface as well,but some adsorbed Cu^(2+)on the calcite surface was desorbed by bonding with OHA,and most of OHA was consumed by Cu^(2+),basic copper carbonate and copper hydroxide.The residual OHA in the pulp was not sufficient for flotation,so calcite flotation was depressed.Finally,a model of the reaction mechanism of Cu^(2+)and OHA on the cassiterite and calcite surfaces was established.展开更多
The flotation separation of cassiterite and dravite was realized using lead complexes of benzohydroxamic acid(Pb-BHA)as a collector and sodium fluosilicate(SF)as a depressant.Zeta potential tests confirmed that SF ena...The flotation separation of cassiterite and dravite was realized using lead complexes of benzohydroxamic acid(Pb-BHA)as a collector and sodium fluosilicate(SF)as a depressant.Zeta potential tests confirmed that SF enabled the selective depression of dravite.The results of Fourier transform infrared(FTIR)spectroscopy analysis demonstrated that hydroxyl-containing groups in the hydrolysis products of SF selectively chemisorbed on the surface of dravite.X-ray photoelectron spectroscopy(XPS)analysis results further demonstrated the strong chemisorption of SF hydrolysis products(F-containing groups and hydroxyl-containing groups)on dravite(Mg sites).Consequently,the adsorption of Pb-BHA on dravite was selectively prevented.Based on the results,a selective depression model of SF on cassiterite and dravite was proposed.展开更多
1.Objective The Eastern Junggar Kalamaili region in Xinjiang constitutes a significant tin metallogenic belt in northwest China(Fig.1a).It hosts four independent tin deposits-Kamusite,Ganliangzi,Beilekuduke,and Saresh...1.Objective The Eastern Junggar Kalamaili region in Xinjiang constitutes a significant tin metallogenic belt in northwest China(Fig.1a).It hosts four independent tin deposits-Kamusite,Ganliangzi,Beilekuduke,and Sareshenke-from west to east,supplemented by two tin mineralized points,namely Hongtujingzi and Sujiquan(Figs.1b).according to the ore type and the composition of gangue minerals,the tin deposits in the region are classified into two groups:Quartz vein type and greisen type,with the Sareshenke deposit ascribed to the former and the remainder to the latter.展开更多
Particle-bubble interaction during electro-flotation of cassiterite was investigated by determining the recovery of cassiterite and the collision mechanism of cassiterite particle and H2 bubble. Flotation tests at dif...Particle-bubble interaction during electro-flotation of cassiterite was investigated by determining the recovery of cassiterite and the collision mechanism of cassiterite particle and H2 bubble. Flotation tests at different conditions were conducted in a single bubble flotation cell. The recovery of cassiterite was found to be affected by cassiterite particle and bubble size. A matching range, in which the best recovery can be obtained, was found between particle and bubble size. Collision, attachment, and detachment of the particle-bubble were observed and captured by a high-speed camera. Particle-bubble collision and attachment were analyzed with the use of particle-bubble interaction theory to obtain the experimental results. An attachment model was introduced and verified through the photos captured by the high-speed camera. A bridge role was observed between the bubbles and particles. Particle-bubble interaction was found to be affected by bubble size and particle size, which significantly influenced not only the collision and attachment behavior of the particles and bubbles but also the flotation recovery of fine cassiterite particles.展开更多
In order to discuss the particle-bubble interaction during the electro-flotation of cassiterite,the recovery of cassiterite with different particle sizes was investigated,and the collision mechanism between the cassit...In order to discuss the particle-bubble interaction during the electro-flotation of cassiterite,the recovery of cassiterite with different particle sizes was investigated,and the collision mechanism between the cassiterite particles and H2 bubbles was explored.The flotation tests were carried out in a single bubble flotation cell.The results show that cassiterite particles 10 μm,10-20 μm,20？38 μm and 38-74 μm match with bubbles with size of 50-150 μm,about 250 μm,74 μm and 74 μm,respectively,and a better recovery can be obtained.It is demonstrated that the recovery of cassiterite is influenced by the size of cassiterite particles and bubbles.Furthermore,the probabilities of collision,adhesion,detachment and collection were calculated using the collision,attachment and collection models.Theoretical calculation results show that the collision probability decreases sharply with decreasing particle size and increasing bubble size（below 150 μm）.The attachment probability would increase from the effective collision,leading to the increase of recovery.展开更多
The flotation behavior and adsorption mechanism of novel（1-hydroxy-2-methyl-2-octenyl） phosphonic acid（HEPA） to cassiterite were investigated by micro-flotation tests, zeta potential measurements, FTIR determinati...The flotation behavior and adsorption mechanism of novel（1-hydroxy-2-methyl-2-octenyl） phosphonic acid（HEPA） to cassiterite were investigated by micro-flotation tests, zeta potential measurements, FTIR determination and density functional theory（DFT） calculation. The flotation results demonstrated that HEPA exhibited superior collecting performance compared with styrene phosphonic acid（SPA）. The cassiterite recovery maintained above 90% over a wide pH range of 2-9 with 50 mg/L HEPA. The results of zeta potential measurement and FTIR detection indicated that the adsorption of HEPA onto cassiterite was mainly attributed to the chemisorption between HEPA monoanions and Sn species on mineral surfaces. The DFT calculation results demonstrated that HEPA monoanions owned higher HOMO energy and exhibited a better affinity to cassiterite than SPA, which provided very clear evidence for the stronger collecting power of HEPA presented in floatation test and zeta potential measurement.展开更多
The effect of octanol in cassiterite flotation using benzohydroxamic acid (BHA) as a collector was investigated. Theadsorption mechanism of octanol and BHA on the surface of cassiterite was analyzed by adsorption expe...The effect of octanol in cassiterite flotation using benzohydroxamic acid (BHA) as a collector was investigated. Theadsorption mechanism of octanol and BHA on the surface of cassiterite was analyzed by adsorption experiments and infrared spectraanalysis. Micro-flotation results indicated that single octanol exhibited almost no collecting power to cassiterite over a wide pHrange. However, as an auxiliary collector, octanol could markedly decrease the consumption of collector BHA and keep the recoveryof cassiterite in high level. The results of adsorption experiments and infrared spectra demonstrated that single octanol was notadsorbed on the surface of cassiterite. It formed adsorption connected with BHA on the surface of cassiterite, and enhanced thehydrophobicity of cassiterite. Octanol promoted the adsorption amount of BHA on the cassiterite surface, and decreased theconsumption of BHA.展开更多
Two reagents including salicylhydroxamic acid(SHA) and tributyl phosphate(TBP) were tested as collectors either separately or together for electro-flotation of fine cassiterite(<10 μm).Subsequently,the flotation m...Two reagents including salicylhydroxamic acid(SHA) and tributyl phosphate(TBP) were tested as collectors either separately or together for electro-flotation of fine cassiterite(<10 μm).Subsequently,the flotation mechanism of the fine cassiterite was investigated by adsorbance determination,electrophoretic mobility measurements and Fourier transform infra-red(FT-IR) spectrum checking.Results of the flotation experiments show that with SHA as a collector,the collecting performance is remarkably impacted by the pulp pH value as the floatability of cassiterite varies sharply when the pH changes,and flotation with SHA gives distinct maximum at about pH 6.5.Additionally,the floatability of cassiterite is determined by using SHA and TBP as collectors.The range of pulp pH for good floatability is broadened in the presence of TBP as auxiliary collector,and the utilization of TBP improves the recovery of cassiterite modestly.Moreover,the optimum pH value for cassiterite flotation is associated with adsorbance.The results of FT-IR spectrum and the electrophoretic mobility measurements indicate that the adsorption interaction between the collectors and the cassiterite is dominantly a kind of chemical bonding in the form of one or two cycle chelate rings due to the coordination of carbonyl group,hydroxamate and P=O group to the metal tin atoms,where the oxygen atoms contained in carbonyl group,hydroxamate and P=O group of the polar groups have the stereo conditions to form five-membered rings.In addition,the adsorption interactions of SHA and TBP on the surfaces of cassiterite are also dominated by means of hydrogen bonds.展开更多
Adhesion is an important process of particle-bubble interaction in fine particle(-10μm)flotation.This paper studied the adhesion process and mechanism between nanobubbles and fine cassiterite particles by using a hig...Adhesion is an important process of particle-bubble interaction in fine particle(-10μm)flotation.This paper studied the adhesion process and mechanism between nanobubbles and fine cassiterite particles by using a high-speed camera,atomic force microscope(AFM),adsorption capacity tests,and induction time tests.After being pretreated with nanobubbles(NBs)water,fine cassiterite particles flotation tests were carried out using caprylhydroxamic acid(CHA)as a collector.The results showed that NBs can improve the recovery and flotation rate of fine cassiterite while decreasing the collector dosage.The adsorption capacity test indicated that the cassiterite treated with NBs had lower demand for collector concentration.The AFM imaging results further demonstrate that NBs could reduce the adsorption of CHA on the surface of minerals.Since NBs played a part of the role of collector,it can improve the flotation effect while reducing the amount of collector.The induction time test and the high-speed camera observation test showed that NBs promoted the attachment between bubbles and cassiterite particles.On the other hand,NBs agglomerate cassiterite particles,increasing the probability of particles colliding with bubbles.展开更多
Flotation of cassiterite has been studied on pure minerals performed in a microflotation cell with various collectors. The results indicate that sulphosuccinamate demonstrates strong collection, good selectivity on ca...Flotation of cassiterite has been studied on pure minerals performed in a microflotation cell with various collectors. The results indicate that sulphosuccinamate demonstrates strong collection, good selectivity on cassiterite in the region around pH 6, and that lead ions have certain activation whereas other ions such as ferric, aluminum, manganese, ferrous, calcium have strong depression on cassiterite flotation. In addition, X ray photoelectron spectroscopy (XPS) was applied to study the flotation systems of cassiterite sulphosuccinamate in the presence and absence of metal cation, and a chemisorption mechanism through chemically bonding between stannum species on the cassiterite surface and oxygen from sulphosuccinamate is proposed. The chemical environment of stannum species would be changed in the presence of lead ions in the flotation systems and therefore improve the activity of the stannum species, while ferric ions show strong depression due to the formation of steady complexes between ferric species and collector.展开更多
Objective The Yangbin porphyry tin deposit in Taishun County of Zhejiang Province is one of the few porphyry-type tin deposits in South China, which is located in the middle portion of the Mesozoic volcanic active bel...Objective The Yangbin porphyry tin deposit in Taishun County of Zhejiang Province is one of the few porphyry-type tin deposits in South China, which is located in the middle portion of the Mesozoic volcanic active belt on the southeastern coast of China. The Yangbin granite porphyry is closely related to the tin mineralization in this region. Based on petrologic and Sr-Nd-Pb isotopic展开更多
The effects of blending Enugu coal and anthracite on tin smelting using Nigerian Dogo Na Hauwa cassiterite have been studied. The work utilized various blends ranging from 100% to 0% anthracite. The content of the Enu...The effects of blending Enugu coal and anthracite on tin smelting using Nigerian Dogo Na Hauwa cassiterite have been studied. The work utilized various blends ranging from 100% to 0% anthracite. The content of the Enugu coal in the blend varied from 5% to 100%. The various tin metal recovery percentage for each batch of smelting using various blends was noted. Anthracite alone had the highest recovery of 71.90% followed by 5% blend of Enugu with anthracite. The result, however, showed that as the Enugu Coal was increased in the blend, the recovery was also decreasing. This equally affected the quality of tin metal recovered by increasing the grade. The work recommended that since the cost of production is the critical issue, 5% - 15% range of Enugu Coal should be used in preparing blends to bring down the cost of imported anthracite which is put at $906.69 per ton. The use of 15% Enugu coal will result in lowering the cost of imported anthracite by $136.0.展开更多
Model for prediction of the concentration of tin extracted during potassium hydroxide leaching of cassiterite has been derived. The model: A = Nt1.53, indicates that the concentration tin extracted is dependent on the...Model for prediction of the concentration of tin extracted during potassium hydroxide leaching of cassiterite has been derived. The model: A = Nt1.53, indicates that the concentration tin extracted is dependent on the residence time. It was found that the validity of the model is rooted in the expression Log A = Log (Nt1.53). Tin extraction per unit time as obtained from experiment and derived model are 2.6666 and 2.6268 mg/min respectively. The maximum deviation of the model-predicted concentration of dissolved tin from the corresponding concentration obtained from the experiment was found to be less than 8%, which is quite within the acceptable deviation limit of experimental results and hence, impacting about 92% confidence coefficient on the model.展开更多
The morphology and elemental characteristics of Kuru Cassiterite ore deposit was performed by the combination of different instruments. This is vital to obtain accurate mineralogical, surface properties and compositio...The morphology and elemental characteristics of Kuru Cassiterite ore deposit was performed by the combination of different instruments. This is vital to obtain accurate mineralogical, surface properties and compositions of the ore. Mineral particles were prepared on epoxy resin, polished and analyzed by a SEM coupled with an EDS. X- ray diffraction showed that the ore contained different minerals of cassiterite, coffinite, siderophyllite,ilmenite, qartz, rutile, manganocolumbite, zircon, tilleyite and monazite. Further quantitative analysis using inductive coupled plasma – optical emission spectrometry gave the elemental analysis as follows;Sn (28.0%), Si (5.5%), Fe (5.16%),Ti (3.51%), Al (2.48%), Y (1.06%), and Nb (2.53%). The other trace elements found include Mn, K, Na, Mg, La, Ce, U and Ca. The ICP-OES data was correlated with the XRD data obtained using the Guassian Pro 8.1 origin software and it showed significant correlation.展开更多
It is known that ore containing cassiterite （SnO2） has been our most important source of tin since antiquity and its successful separation continuously pose problems to mineral processors. The situation is more pron...It is known that ore containing cassiterite （SnO2） has been our most important source of tin since antiquity and its successful separation continuously pose problems to mineral processors. The situation is more pronounced since the depletion of the more easily recoverable alluvial reserves forces us to work with the more complex deposits such as hardrock cassiterite ores. In order to understand more about the challenges in processing complex tin ore deposits, a metasedimentary rock ore sample from a mine in Malaysia was used in this study. Chemical analysis by wet method shows that SnO2 content in the sample was 2.86%, while for mineralogical analysis, the x-ray diffractogram （XRD） of the sample had identified that besides cassiterite, the sample also contained minerals such as quartz （SiO2） and clinochlore. Furthermore, the FESEM （field emission scanning electron microscope） micrograph analysis carried out on a polish section of the sample indicated that the fine cassiterite particles （approximately 80 ~tm） were found to be disseminated in the quartz minerals. Prior to the separation processes, grindability studies were carried-out on crushed samples to liberate the cassiterite from other gangue minerals and at the same time, avoid producing high percentage of fines. For the separation of tin from gangue minerals on the ground samples, two stages of gravity separations by shaking tables were carried out. The first stage was run on ground samples and for the second stage, the middling product from the first stage was re-tabled. Magnetic separation process on Concentrate 1 （stage 1） and Concentrate 2 （stage 2） products from the shaking table increased the grade of SnO2 to 46.85% and 61.90% respectively （as a non-magnetic products）. Further concentration process of these non-magnetic products by high tension separator, increased the grade of SnO2 from 85.05% to 98.77%.展开更多
In this work we evaluate the role of a natural mineralizer-oxide like cassiterite (SnO2) on the cement properties. In particular, we study the effect of different quantities of SnO2 with 0.5, 1.0, 1.5 and 2.0 wt% on b...In this work we evaluate the role of a natural mineralizer-oxide like cassiterite (SnO2) on the cement properties. In particular, we study the effect of different quantities of SnO2 with 0.5, 1.0, 1.5 and 2.0 wt% on burnability of industrial raw mix by free lime evaluation. We obtain four datasets, with successive increase of temperature at 1250℃, 1350℃, 1400℃ and 1450℃. We study the produced cassiterite-added clinker with X-ray diffraction (XRD), thermal analysis (DTA) and scanning electron microscopy (SEM). Though, we characterize the new phases formed and whether, adding excess SnO2 is promote forms of C3S, C2S influencing the final quality of cement.展开更多
Huge amounts of tailing dumps as a result of mines’ blasting operations were impacting economic and environmental problems. Evaluation of one of these tailing dumps of the Eastern Desert of Egypt showed the presence ...Huge amounts of tailing dumps as a result of mines’ blasting operations were impacting economic and environmental problems. Evaluation of one of these tailing dumps of the Eastern Desert of Egypt showed the presence of reasonable amount of cassiterite mineral reaching 0.199% SnO<sub>2</sub>. The mineral cassiterite was found as finely disseminated particulates, reached to 5 microns, within varieties of quartz-feldspar-hornblende-biotite granitic formations. In the present study, the processing regime considered from the beginning the alignment between reaching cassiterite mineral liberation size, and its extreme brittleness character. Stirring ball milling technique was applied to produce <span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span>0.51 mm product with minimum fines as possible, which was left aside for a separate study. The ground product <span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span>0.51 + 0.074 mm was subjected to joint shaking table/dry high intensity magnetic separation techniques after splitting it into two fractions, <span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span>0.51 + 0.21 mm and <span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span>0.21 + 0.074 mm. Each fraction was separately subjected to “Wilfley” shaking table. At optimum conditions, a shaking table concentrate was obtained with 0.29% SnO<sub>2</sub> and an operational recovery reached 96.94% from a feeding contained 0.19% SnO<sub>2</sub>. The heavies and the two middling products after shaking table were directed separately after dryness to dry high intensity magnetic separation using “Eriez” rare earth roll separator, meanwhile the light fractions were rejected. Mathematically designed experiments were applied to optimize the separation process. At optimum conditions, a final cassiterite concentrate was obtained with 11.25% SnO<sub>2</sub>, and an operational recovery 94.08%. In addition, a topaz mineral concentrate was separated at splitter angle 65<span style="white-space:nowrap;"><span style="white-space:nowrap;">˚</span></span>.展开更多
Owing to the lack of effective beneficiation technologies,valuable wolframite and cassiterite resources are lost in the tailings of tungsten-tin polymetallic mines.For Shizhuyuan polymetallic mine,the recovery efficie...Owing to the lack of effective beneficiation technologies,valuable wolframite and cassiterite resources are lost in the tailings of tungsten-tin polymetallic mines.For Shizhuyuan polymetallic mine,the recovery efficiencies of wolframite and cassiterite were significantly lower than those of scheelite using existing process.In this study,the underlying causes were investigated based on the flotation kinetics,surface hydration characteristics of the three target minerals,and the adsorption behavior of the collector.To enhance the comprehensive recovery of wolframite and cassiterite from the tailings,a novel double-ligand collector,Pb-BHA-SDBS(lead-benzohydroxamic acid-sodium dodecyl benzene sulfonate),was designed and successfully implemented in the Shizhuyuan polymetallic mine.Accordingly,a novel beneficiation process combining flotation and gravity separation was developed,yielding an additional low-grade W-Sn mixed concentrate.This process not only generates economic value for enterprises but also provides a reference for the comprehensive utilization of tungsten-tin polymetallic ore in the Nanling metallogenic belt of China.展开更多
Cassiterite(SnO_(2))is the main ore mineral of tin in magmatic-hydrothermal tin deposits,but tin transport and precipitation mechanisms from hydrothermal fluids remain poorly understood.We critically evalu-ated aqueou...Cassiterite(SnO_(2))is the main ore mineral of tin in magmatic-hydrothermal tin deposits,but tin transport and precipitation mechanisms from hydrothermal fluids remain poorly understood.We critically evalu-ated aqueous tin speciation in hydrothermal fluids from extensive experimental data and thermody-namic modeling.Sn(II)chloride complexes in hydrothermal fluids exist mainly as SnCl^(+),SnCl_(2)(aq),and SnCl_(3).The revised Helgeson-Kirkham-Flowers model parameters of these three tin species and two tin ions(Sn^(4+)and Sn^(2+))were derived from the correlation algorithms among these parameters,and the standard molar properties of cassiterite were optimized to be internally consistent with the available thermodynamic dataset.These thermodynamic parameters,together with the available equilibrium con-stant equation of Sn(IV)chloride complexes,could reproduce the available solubility data of cassiterite in acidic solutions at 400-700℃under oxygen fugacity(f_(o2))levels buffered by hematite-magnetite(HM)or nickel-nickel oxide(NNO).These comparisons allow modeling chemical systems of SnO_(2)-NaCl-HCI-H_(2)O(liquid phase)to examine tin transport and cassiterite precipitation mechanisms under tin-mineralizing conditions:300--500℃,50-150 MPa,2 molal NaCI,and fo。levels from QFM(quartz-fayalite-magnetite)to HM.Sn(I)chloride complexes are commonly interpreted to dominate in aqueous tin speciation under f_(o2)=NNO,but our modeling results indicate that considerable contents of Sn(IV)chloride complexes also exist in those reduced fluids with high HCI contents,consistent with recent in situ high-temperature experiments and molecular dynamic simulations.The Sn(I)/Sn(IV)ratios in fluids depends onfo,temperature,and HCl contents.A considerable amount of Sn(IV)possibly exist in an early mineralization stage even under f_(o2)=NNO;if so,redox reactions are unnecessary to precipitate cassiterite from these mineralizing fluids.We find that even if the f_(o2)levels are constant,simple cooling can alter mineralizing fluids to be more oxidized(e.g.,from QFM to HM)and cause cassiterite precipitation,indicating that oxidizing agents are not necessary as previously thought.This explains why cassiterite can precipitate in host rocks(e.g.,sandstone or quartzite)that do not provide oxidizing agents.A simple rise in f_(o2),levels and pH neutralization(e.g.,greisenization)also cause cassiterite precipitation.Cassiterite solubility in oxidized acidic hydrothermal fluids(NNO<f_(o2),<HM)is high enough to account for the tin contents of fluid inclusions from typical tin deposits,but the mineralization potential of oxdized fluids is inferior to reduced fluids(f_(o2),≤NNO)under the same conditions.展开更多
基金supported by Yunnan Science and Technology Leading Talent Project(No.202305AB350005)。
文摘Tin is a critical metal for various industries,making its recovery from low-grade cassiterite ores crucial.This study aimed to optimize the flotation recovery of cassiterite using multi-component collector systems.Several collectors were initially selected through micro-flotation tests,leading to the identification of optimal proportions for a four-component collector system(SHA-OHA-SPA-DBIA in a 4:3:2:1 ratio).Molecular dynamics simulations and surface tension tests were used to investigate the micellar behavior of these collectors in aqueous solution.The adsorption characteristics were quantified using microcalorimetry,enabling the determination of collection entropy and changes in Gibbs free energy.The four-component collector system showed the highest entropy change and the most favorable Gibbs free energy,leading to a cassiterite recovery of above 90%at a concentration of 8.0×10^(5)mol/L.Various analytical techniques were employed to systematically characterize the adsorption mechanism.The findings revealed a positive correlation between the adsorption products formed by the multicomponent collectors on the cassiterite surface and the entropy changes.Industrial-scale testing of the high-entropy collector system produced a tin concentrate with an Sn grade of 6.17%and an Sn recovery of 82.43%,demonstrating its substantial potential for practical applications in cassiterite flotation.
基金Project(52074355)supported by the National Natural Science Foundation of ChinaProject(2023JJ10070)supported by the Outstanding Youth Scientist Foundation of Hunan Province,China。
文摘In this study,the effect of Cu^(2+)on the cassiterite and calcite flotation using octanohydroxamic acid(OHA)as collector was investigated through flotation tests,solution reaction tests and calculation,zeta potential measurements,XPS analysis and residual reagent concentration measurements.Results indicated that Cu^(2+)played an activation role on cassiterite flotation but a depression role on calcite flotation.The copper cations were adsorbed on the cassiterite surface by forming a Cu—O bond,and the pre-adsorbed copper cations and the OHA-Cu complexes promoted the adsorption of OHA on the cassiterite surface.Thus,cassiterite flotation was activated.The dissolved HCO_(3)-in the calcite pulp underwent a double hydrolysis reaction with copper cations(Cu^(2+),CuOH^(+),Cu_(2)(OH)_(2)^(2+)and Cu_(3)(OH)_(4)^(2+))to form CuCO_(3).Some copper cations were adsorbed on the calcite surface as well,but some adsorbed Cu^(2+)on the calcite surface was desorbed by bonding with OHA,and most of OHA was consumed by Cu^(2+),basic copper carbonate and copper hydroxide.The residual OHA in the pulp was not sufficient for flotation,so calcite flotation was depressed.Finally,a model of the reaction mechanism of Cu^(2+)and OHA on the cassiterite and calcite surfaces was established.
基金supported by the National Natural Science Foundation of China(No.52122406)the National Key Research Center and Development Program of the 14th Five-year Plan of China(Nos.2022YFC2905104,2022YFC2905105).
文摘The flotation separation of cassiterite and dravite was realized using lead complexes of benzohydroxamic acid(Pb-BHA)as a collector and sodium fluosilicate(SF)as a depressant.Zeta potential tests confirmed that SF enabled the selective depression of dravite.The results of Fourier transform infrared(FTIR)spectroscopy analysis demonstrated that hydroxyl-containing groups in the hydrolysis products of SF selectively chemisorbed on the surface of dravite.X-ray photoelectron spectroscopy(XPS)analysis results further demonstrated the strong chemisorption of SF hydrolysis products(F-containing groups and hydroxyl-containing groups)on dravite(Mg sites).Consequently,the adsorption of Pb-BHA on dravite was selectively prevented.Based on the results,a selective depression model of SF on cassiterite and dravite was proposed.
基金supported by the National Key R&D Program of China(No.2021YFC2901802)project of the China Geological Survey(No.DD20240073)Key R&D Program of Shaanxi Province(No.2024GH-ZDXM-26).
文摘1.Objective The Eastern Junggar Kalamaili region in Xinjiang constitutes a significant tin metallogenic belt in northwest China(Fig.1a).It hosts four independent tin deposits-Kamusite,Ganliangzi,Beilekuduke,and Sareshenke-from west to east,supplemented by two tin mineralized points,namely Hongtujingzi and Sujiquan(Figs.1b).according to the ore type and the composition of gangue minerals,the tin deposits in the region are classified into two groups:Quartz vein type and greisen type,with the Sareshenke deposit ascribed to the former and the remainder to the latter.
基金Project(50774094)supported by the National Natural Science Foundation of ChinaProject(2011BAB05B01)supported by the National Key Technology Research and Development Program of ChinaProject(2013M542076)supported by the Postdoctoral Science Foundation of China
文摘Particle-bubble interaction during electro-flotation of cassiterite was investigated by determining the recovery of cassiterite and the collision mechanism of cassiterite particle and H2 bubble. Flotation tests at different conditions were conducted in a single bubble flotation cell. The recovery of cassiterite was found to be affected by cassiterite particle and bubble size. A matching range, in which the best recovery can be obtained, was found between particle and bubble size. Collision, attachment, and detachment of the particle-bubble were observed and captured by a high-speed camera. Particle-bubble collision and attachment were analyzed with the use of particle-bubble interaction theory to obtain the experimental results. An attachment model was introduced and verified through the photos captured by the high-speed camera. A bridge role was observed between the bubbles and particles. Particle-bubble interaction was found to be affected by bubble size and particle size, which significantly influenced not only the collision and attachment behavior of the particles and bubbles but also the flotation recovery of fine cassiterite particles.
基金Project(50774094)supported by the National Natural Science Foundation of ChinaProject(2010CB630905)supported by the National Basic Research Program of China
文摘In order to discuss the particle-bubble interaction during the electro-flotation of cassiterite,the recovery of cassiterite with different particle sizes was investigated,and the collision mechanism between the cassiterite particles and H2 bubbles was explored.The flotation tests were carried out in a single bubble flotation cell.The results show that cassiterite particles 10 μm,10-20 μm,20？38 μm and 38-74 μm match with bubbles with size of 50-150 μm,about 250 μm,74 μm and 74 μm,respectively,and a better recovery can be obtained.It is demonstrated that the recovery of cassiterite is influenced by the size of cassiterite particles and bubbles.Furthermore,the probabilities of collision,adhesion,detachment and collection were calculated using the collision,attachment and collection models.Theoretical calculation results show that the collision probability decreases sharply with decreasing particle size and increasing bubble size（below 150 μm）.The attachment probability would increase from the effective collision,leading to the increase of recovery.
基金Project(2013AA064102)supported by the 12th Five-year Plan of National Scientific and Technological Program of China
文摘The flotation behavior and adsorption mechanism of novel（1-hydroxy-2-methyl-2-octenyl） phosphonic acid（HEPA） to cassiterite were investigated by micro-flotation tests, zeta potential measurements, FTIR determination and density functional theory（DFT） calculation. The flotation results demonstrated that HEPA exhibited superior collecting performance compared with styrene phosphonic acid（SPA）. The cassiterite recovery maintained above 90% over a wide pH range of 2-9 with 50 mg/L HEPA. The results of zeta potential measurement and FTIR detection indicated that the adsorption of HEPA onto cassiterite was mainly attributed to the chemisorption between HEPA monoanions and Sn species on mineral surfaces. The DFT calculation results demonstrated that HEPA monoanions owned higher HOMO energy and exhibited a better affinity to cassiterite than SPA, which provided very clear evidence for the stronger collecting power of HEPA presented in floatation test and zeta potential measurement.
基金Project(B14034)supported by the National "111" Project of Ministry of Education of ChinaProject(2015CX005)supported by the Innovation Driven Plan of Central South University,ChinaProject supported by the 2014 Sublimation Scholar Program of Central South University,China
文摘The effect of octanol in cassiterite flotation using benzohydroxamic acid (BHA) as a collector was investigated. Theadsorption mechanism of octanol and BHA on the surface of cassiterite was analyzed by adsorption experiments and infrared spectraanalysis. Micro-flotation results indicated that single octanol exhibited almost no collecting power to cassiterite over a wide pHrange. However, as an auxiliary collector, octanol could markedly decrease the consumption of collector BHA and keep the recoveryof cassiterite in high level. The results of adsorption experiments and infrared spectra demonstrated that single octanol was notadsorbed on the surface of cassiterite. It formed adsorption connected with BHA on the surface of cassiterite, and enhanced thehydrophobicity of cassiterite. Octanol promoted the adsorption amount of BHA on the cassiterite surface, and decreased theconsumption of BHA.
基金Project(50774094) supported by the National Natural Science Foundation of ChinaProject(2010CB630905) supported by the National Basic Research Program of China
文摘Two reagents including salicylhydroxamic acid(SHA) and tributyl phosphate(TBP) were tested as collectors either separately or together for electro-flotation of fine cassiterite(<10 μm).Subsequently,the flotation mechanism of the fine cassiterite was investigated by adsorbance determination,electrophoretic mobility measurements and Fourier transform infra-red(FT-IR) spectrum checking.Results of the flotation experiments show that with SHA as a collector,the collecting performance is remarkably impacted by the pulp pH value as the floatability of cassiterite varies sharply when the pH changes,and flotation with SHA gives distinct maximum at about pH 6.5.Additionally,the floatability of cassiterite is determined by using SHA and TBP as collectors.The range of pulp pH for good floatability is broadened in the presence of TBP as auxiliary collector,and the utilization of TBP improves the recovery of cassiterite modestly.Moreover,the optimum pH value for cassiterite flotation is associated with adsorbance.The results of FT-IR spectrum and the electrophoretic mobility measurements indicate that the adsorption interaction between the collectors and the cassiterite is dominantly a kind of chemical bonding in the form of one or two cycle chelate rings due to the coordination of carbonyl group,hydroxamate and P=O group to the metal tin atoms,where the oxygen atoms contained in carbonyl group,hydroxamate and P=O group of the polar groups have the stereo conditions to form five-membered rings.In addition,the adsorption interactions of SHA and TBP on the surfaces of cassiterite are also dominated by means of hydrogen bonds.
基金financially supported by the National Natural Science Foundation of China(Nos.U2003129 and 51504175)China Scholarship Council(No.201706955031)。
文摘Adhesion is an important process of particle-bubble interaction in fine particle(-10μm)flotation.This paper studied the adhesion process and mechanism between nanobubbles and fine cassiterite particles by using a high-speed camera,atomic force microscope(AFM),adsorption capacity tests,and induction time tests.After being pretreated with nanobubbles(NBs)water,fine cassiterite particles flotation tests were carried out using caprylhydroxamic acid(CHA)as a collector.The results showed that NBs can improve the recovery and flotation rate of fine cassiterite while decreasing the collector dosage.The adsorption capacity test indicated that the cassiterite treated with NBs had lower demand for collector concentration.The AFM imaging results further demonstrate that NBs could reduce the adsorption of CHA on the surface of minerals.Since NBs played a part of the role of collector,it can improve the flotation effect while reducing the amount of collector.The induction time test and the high-speed camera observation test showed that NBs promoted the attachment between bubbles and cassiterite particles.On the other hand,NBs agglomerate cassiterite particles,increasing the probability of particles colliding with bubbles.
文摘Flotation of cassiterite has been studied on pure minerals performed in a microflotation cell with various collectors. The results indicate that sulphosuccinamate demonstrates strong collection, good selectivity on cassiterite in the region around pH 6, and that lead ions have certain activation whereas other ions such as ferric, aluminum, manganese, ferrous, calcium have strong depression on cassiterite flotation. In addition, X ray photoelectron spectroscopy (XPS) was applied to study the flotation systems of cassiterite sulphosuccinamate in the presence and absence of metal cation, and a chemisorption mechanism through chemically bonding between stannum species on the cassiterite surface and oxygen from sulphosuccinamate is proposed. The chemical environment of stannum species would be changed in the presence of lead ions in the flotation systems and therefore improve the activity of the stannum species, while ferric ions show strong depression due to the formation of steady complexes between ferric species and collector.
基金supported by the National Key R&D Program of China (grant No. 2016YFC0600405)the National Natural Science Foundation of China (grants No. 41672079 and 41372085)Strategic Priority Research Program (B) of the Chinese Academy of Sciences (grant No. XDB1803206)
文摘Objective The Yangbin porphyry tin deposit in Taishun County of Zhejiang Province is one of the few porphyry-type tin deposits in South China, which is located in the middle portion of the Mesozoic volcanic active belt on the southeastern coast of China. The Yangbin granite porphyry is closely related to the tin mineralization in this region. Based on petrologic and Sr-Nd-Pb isotopic
文摘The effects of blending Enugu coal and anthracite on tin smelting using Nigerian Dogo Na Hauwa cassiterite have been studied. The work utilized various blends ranging from 100% to 0% anthracite. The content of the Enugu coal in the blend varied from 5% to 100%. The various tin metal recovery percentage for each batch of smelting using various blends was noted. Anthracite alone had the highest recovery of 71.90% followed by 5% blend of Enugu with anthracite. The result, however, showed that as the Enugu Coal was increased in the blend, the recovery was also decreasing. This equally affected the quality of tin metal recovered by increasing the grade. The work recommended that since the cost of production is the critical issue, 5% - 15% range of Enugu Coal should be used in preparing blends to bring down the cost of imported anthracite which is put at $906.69 per ton. The use of 15% Enugu coal will result in lowering the cost of imported anthracite by $136.0.
文摘Model for prediction of the concentration of tin extracted during potassium hydroxide leaching of cassiterite has been derived. The model: A = Nt1.53, indicates that the concentration tin extracted is dependent on the residence time. It was found that the validity of the model is rooted in the expression Log A = Log (Nt1.53). Tin extraction per unit time as obtained from experiment and derived model are 2.6666 and 2.6268 mg/min respectively. The maximum deviation of the model-predicted concentration of dissolved tin from the corresponding concentration obtained from the experiment was found to be less than 8%, which is quite within the acceptable deviation limit of experimental results and hence, impacting about 92% confidence coefficient on the model.
文摘The morphology and elemental characteristics of Kuru Cassiterite ore deposit was performed by the combination of different instruments. This is vital to obtain accurate mineralogical, surface properties and compositions of the ore. Mineral particles were prepared on epoxy resin, polished and analyzed by a SEM coupled with an EDS. X- ray diffraction showed that the ore contained different minerals of cassiterite, coffinite, siderophyllite,ilmenite, qartz, rutile, manganocolumbite, zircon, tilleyite and monazite. Further quantitative analysis using inductive coupled plasma – optical emission spectrometry gave the elemental analysis as follows;Sn (28.0%), Si (5.5%), Fe (5.16%),Ti (3.51%), Al (2.48%), Y (1.06%), and Nb (2.53%). The other trace elements found include Mn, K, Na, Mg, La, Ce, U and Ca. The ICP-OES data was correlated with the XRD data obtained using the Guassian Pro 8.1 origin software and it showed significant correlation.
文摘It is known that ore containing cassiterite （SnO2） has been our most important source of tin since antiquity and its successful separation continuously pose problems to mineral processors. The situation is more pronounced since the depletion of the more easily recoverable alluvial reserves forces us to work with the more complex deposits such as hardrock cassiterite ores. In order to understand more about the challenges in processing complex tin ore deposits, a metasedimentary rock ore sample from a mine in Malaysia was used in this study. Chemical analysis by wet method shows that SnO2 content in the sample was 2.86%, while for mineralogical analysis, the x-ray diffractogram （XRD） of the sample had identified that besides cassiterite, the sample also contained minerals such as quartz （SiO2） and clinochlore. Furthermore, the FESEM （field emission scanning electron microscope） micrograph analysis carried out on a polish section of the sample indicated that the fine cassiterite particles （approximately 80 ~tm） were found to be disseminated in the quartz minerals. Prior to the separation processes, grindability studies were carried-out on crushed samples to liberate the cassiterite from other gangue minerals and at the same time, avoid producing high percentage of fines. For the separation of tin from gangue minerals on the ground samples, two stages of gravity separations by shaking tables were carried out. The first stage was run on ground samples and for the second stage, the middling product from the first stage was re-tabled. Magnetic separation process on Concentrate 1 （stage 1） and Concentrate 2 （stage 2） products from the shaking table increased the grade of SnO2 to 46.85% and 61.90% respectively （as a non-magnetic products）. Further concentration process of these non-magnetic products by high tension separator, increased the grade of SnO2 from 85.05% to 98.77%.
文摘In this work we evaluate the role of a natural mineralizer-oxide like cassiterite (SnO2) on the cement properties. In particular, we study the effect of different quantities of SnO2 with 0.5, 1.0, 1.5 and 2.0 wt% on burnability of industrial raw mix by free lime evaluation. We obtain four datasets, with successive increase of temperature at 1250℃, 1350℃, 1400℃ and 1450℃. We study the produced cassiterite-added clinker with X-ray diffraction (XRD), thermal analysis (DTA) and scanning electron microscopy (SEM). Though, we characterize the new phases formed and whether, adding excess SnO2 is promote forms of C3S, C2S influencing the final quality of cement.
文摘Huge amounts of tailing dumps as a result of mines’ blasting operations were impacting economic and environmental problems. Evaluation of one of these tailing dumps of the Eastern Desert of Egypt showed the presence of reasonable amount of cassiterite mineral reaching 0.199% SnO<sub>2</sub>. The mineral cassiterite was found as finely disseminated particulates, reached to 5 microns, within varieties of quartz-feldspar-hornblende-biotite granitic formations. In the present study, the processing regime considered from the beginning the alignment between reaching cassiterite mineral liberation size, and its extreme brittleness character. Stirring ball milling technique was applied to produce <span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span>0.51 mm product with minimum fines as possible, which was left aside for a separate study. The ground product <span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span>0.51 + 0.074 mm was subjected to joint shaking table/dry high intensity magnetic separation techniques after splitting it into two fractions, <span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span>0.51 + 0.21 mm and <span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span>0.21 + 0.074 mm. Each fraction was separately subjected to “Wilfley” shaking table. At optimum conditions, a shaking table concentrate was obtained with 0.29% SnO<sub>2</sub> and an operational recovery reached 96.94% from a feeding contained 0.19% SnO<sub>2</sub>. The heavies and the two middling products after shaking table were directed separately after dryness to dry high intensity magnetic separation using “Eriez” rare earth roll separator, meanwhile the light fractions were rejected. Mathematically designed experiments were applied to optimize the separation process. At optimum conditions, a final cassiterite concentrate was obtained with 11.25% SnO<sub>2</sub>, and an operational recovery 94.08%. In addition, a topaz mineral concentrate was separated at splitter angle 65<span style="white-space:nowrap;"><span style="white-space:nowrap;">˚</span></span>.
基金financially supported by the National Natural Science Foundation of China(Nos.52122406 and 52374291)National Key Research and Development Program of the 14th Five-Year Plan(Nos.2022YFC2905105 and 2022YFC2905104)。
文摘Owing to the lack of effective beneficiation technologies,valuable wolframite and cassiterite resources are lost in the tailings of tungsten-tin polymetallic mines.For Shizhuyuan polymetallic mine,the recovery efficiencies of wolframite and cassiterite were significantly lower than those of scheelite using existing process.In this study,the underlying causes were investigated based on the flotation kinetics,surface hydration characteristics of the three target minerals,and the adsorption behavior of the collector.To enhance the comprehensive recovery of wolframite and cassiterite from the tailings,a novel double-ligand collector,Pb-BHA-SDBS(lead-benzohydroxamic acid-sodium dodecyl benzene sulfonate),was designed and successfully implemented in the Shizhuyuan polymetallic mine.Accordingly,a novel beneficiation process combining flotation and gravity separation was developed,yielding an additional low-grade W-Sn mixed concentrate.This process not only generates economic value for enterprises but also provides a reference for the comprehensive utilization of tungsten-tin polymetallic ore in the Nanling metallogenic belt of China.
基金financially funded by CGS Research Fund(DZLXJK202103,DZLXJK202206,DZLXJK202203)China Geologi-cal Survey project(DD20230344)+1 种基金Guizhou Provincial Science and Technology Project(Qiankehezhicheng[2021]408)major project of Guizhou Bureau of Geology and Mineral Resources Exploration and Development(Qiandikuangkehe[2021]1).
文摘Cassiterite(SnO_(2))is the main ore mineral of tin in magmatic-hydrothermal tin deposits,but tin transport and precipitation mechanisms from hydrothermal fluids remain poorly understood.We critically evalu-ated aqueous tin speciation in hydrothermal fluids from extensive experimental data and thermody-namic modeling.Sn(II)chloride complexes in hydrothermal fluids exist mainly as SnCl^(+),SnCl_(2)(aq),and SnCl_(3).The revised Helgeson-Kirkham-Flowers model parameters of these three tin species and two tin ions(Sn^(4+)and Sn^(2+))were derived from the correlation algorithms among these parameters,and the standard molar properties of cassiterite were optimized to be internally consistent with the available thermodynamic dataset.These thermodynamic parameters,together with the available equilibrium con-stant equation of Sn(IV)chloride complexes,could reproduce the available solubility data of cassiterite in acidic solutions at 400-700℃under oxygen fugacity(f_(o2))levels buffered by hematite-magnetite(HM)or nickel-nickel oxide(NNO).These comparisons allow modeling chemical systems of SnO_(2)-NaCl-HCI-H_(2)O(liquid phase)to examine tin transport and cassiterite precipitation mechanisms under tin-mineralizing conditions:300--500℃,50-150 MPa,2 molal NaCI,and fo。levels from QFM(quartz-fayalite-magnetite)to HM.Sn(I)chloride complexes are commonly interpreted to dominate in aqueous tin speciation under f_(o2)=NNO,but our modeling results indicate that considerable contents of Sn(IV)chloride complexes also exist in those reduced fluids with high HCI contents,consistent with recent in situ high-temperature experiments and molecular dynamic simulations.The Sn(I)/Sn(IV)ratios in fluids depends onfo,temperature,and HCl contents.A considerable amount of Sn(IV)possibly exist in an early mineralization stage even under f_(o2)=NNO;if so,redox reactions are unnecessary to precipitate cassiterite from these mineralizing fluids.We find that even if the f_(o2)levels are constant,simple cooling can alter mineralizing fluids to be more oxidized(e.g.,from QFM to HM)and cause cassiterite precipitation,indicating that oxidizing agents are not necessary as previously thought.This explains why cassiterite can precipitate in host rocks(e.g.,sandstone or quartzite)that do not provide oxidizing agents.A simple rise in f_(o2),levels and pH neutralization(e.g.,greisenization)also cause cassiterite precipitation.Cassiterite solubility in oxidized acidic hydrothermal fluids(NNO<f_(o2),<HM)is high enough to account for the tin contents of fluid inclusions from typical tin deposits,but the mineralization potential of oxdized fluids is inferior to reduced fluids(f_(o2),≤NNO)under the same conditions.
