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By Gu Guohua

The alteration of surface properties of chalcopyrite after biological conditioning with Leptospirillum ferriphilum was studied by adsorption, zeta-potential, contact angle and bioleaching tests. The strains of L. ferriphilum cultured using different energy sources (either soluble ferrous ion or chalcopyrite) were used. The adhesion of bacteria to the chalcopyrite surface was a fast process. Additionally, the adsorption of substrate-grown bacteria was greater and faster than that of liquid-grown ones. The isoelectric point (IEP) of chalcopyrite moved toward that of pure L. ferriphilum after conditioning with bacteria. The chalcopyrite contact angle curves motioned diversely in the 9K culture with and without chalcopyrite powders. The results of X-ray diffraction patterns (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) analysis indicated that in the bioleaching process by L. ferriphilum, the surface of chalcopyrite was covered with sulfur and jarosite. Furthermore, iron phase dissolved preferentially from chalcopyrite surface during bioleaching from EDS detection. The copper extraction was low resulting from the formation of a passivation layer. The major component of the passivation layer that blocked continuous copper extraction was sulfur, not jarosite.

Sep 1, 2012

By Liu Yong

A complex rare metal ore, containing various valuable elements is used in this study. The mineralogy results indicate that the mineral composition of the raw ore is complex, and there are more than thirty-eight kinds of minerals in the raw ore, and the elements, such as Nb, Ti, Fe, REO, Be etc, always form isomorphism relationship. The REO content of the raw ore is 0.45%, and the contents of other rare metals Nb, Ta, Ti and Zr are 0.33%, 0.02%, 0.93% and 2.00% respectively, and the main gangue elements are Si and Al, and their contents are 71.84% and 8.5% respectively. The beneficiation-metallurgy combination process of ?preconcentration-reduction and magnetic separation-acidification and leaching-precipitation? is used to treat the raw ore. The preconcentration of raw ore is realized through high intensity magnetic separation, and the magnetic field intensity is 1.0T, and the rough concentrate with 2.88% REO and 1.95% Nbresidue can be obtained, and the iron recovery is 92.83%, and the REO recovery is 95.87%, and the Nbresidue is treated by hydrometallurgy process of ?acidification-leaching-precipitation?, then the rare earth oxide, niobium concentrate and zircon-bearing residue can be obtained, and the REO recovery is 80.10% and the Nbresidue and the gangue obtained from the high intensity magnetic separation process is separated by gravity separation, and then the zirconium concentrate can be obtained. The indexes of the beneficiation-metallurgy combination process used to treat the complex rare metal ore are as follows. The REO content of the rare earth oxide is 92.58% and the recovery is 58.44%. The Nb2O5 and 27.42% TFe can be obtained. Iron in rough concentrates is removed after reduction and low intensity magnetic separation, then the iron powder with Fe content over 88% and nonmagnetic rare-metal 2O5 recovery is 94.77%. The rare-metal 2O5 recovery is 80.04%. The mixture of the zircon-bearing 2O5 content of niobium concentrate is 28.34% and the recovery is 54.02%. The ZrO2 content of zirconium concentrate is 28.43% and the recovery is 52.35%. The TFe of iron powder is 89.53% and the recovery is 78.13%. Keywords: rare metal ore, separation and extraction, beneficiation-metallurgy combination, comprehensive utilization

Sep 1, 2012

By J. Y. P. Leite

In the Borborema Pegmatitic Province (Brazil) exploitations of several minerals are conducted by small producers. They use traditional techniques of gravity concentration in small-scale plants as jigs and vibratory tables. During decades the mining activity generated tailings with economic interest in particularly columbite-tantalite. Samples collected in tailing piles of a gravity plant were characterized in mineral composition, which shows in the heavy fraction the minerals spodumene, columbite-tantalite, ilmeno-hematite, garnet and cassiterite. The light fraction presents quartz, feldspar and muscovite. The degree of liberation of spodumene and columbite-tantalite were determined using optical microscopy that presents liberation in 100 µm (90% to columbite-tantalite and 100% to spodumene). Centrifugal concentrator Falcon SB-40 was used for concentration of these minerals and presents 65% recovery in mass to two stages with mass reduction about 85%.

Sep 1, 2012

By Yosep Han

Mechanically-induced chemical reactions between natural beach ilmenite (FeTiO3) and silicon (Si) have been examined by a combination of X-ray diffraction (XRD) and scanning electronic microscopy (SEM) analyses. The effect of various milling time on the phase transformation, crystallite size, and lattice strain of a beach sand ilmenite with silicon, and on their leaching behavior in hydrochloric acid (HCl) has been investigated. For mechanically activated FeTiO3, the crystallite size decreased and lattice strain increased monotonically with time of milling. However, the mechanochemically synthesized ilmenite with silicon showed a relatively smaller crystallite size and greater lattice strain compared with the mechanically activated ilmenite under the same milling condition. In accordance with the elapse of milling time, the intensity of both pure FeTiO3 and mechanically activated FeTiO3 gradually decreased. However, in case of the mechanochemically synthesized ilmenitereduction of FeTiO3 by silicon resulted in formation of rutile TiO2 at the milling time of 20 h and afterwards. Additional leaching experiments were carried out at an HCl/ilmenite (wt%) ratio of 20:1. The concentration of HCl was 3 M and the reaction temperature ranged from 70 to 90 oC. Mechanical activation was observed to significantly enhance the dissolution rates of both iron (Fe) and titanium (Ti) in HCl. Particularly, effects of both milling time and silicon addition on the dissolution rates of titanium and iron were significant, while those of temperature were relatively minor under the conditions investigated in this study. Keywords: mechanochemical treatment, natural beach ilmenite, silicon, leaching behavior

Sep 1, 2012

By Kyoungkeun Yoo

A citric acid leaching test after heavy medium separation process was performed to remove the heavy metal contaminat such as Pb, Cu, and Zn from contaminated soil. The lead component was removed from soil by heavy medium separation whereas zinc component shows 0 % - 37.9 % removal ratio with particle size. The citric acid leaching was conducted to remove the remained zinc component. The removal ratio of Zn reached to more than 95 % under the conditions; 10 % in pulp density, 200 rpm in agitation speed, 50 °C, 2 mol/L in citric acid concentration at 2 hrs in leaching time. These results suggest that the heavy medium separation method followed by citric acid leaching is effective for treatment of soil contaminated with various chemical forms of heavy metal. Keywords: metal contaminated soil, citrate, heavy medium separation, zinc

Sep 1, 2012

By X. M. Chen

The selection of leach reagent mainly according to the ratio of useful mineral to gangue in mineral raw material and the structure of mineral raw material. Besides that the price of reagent, the capability of reagent decomposing mineral and its causticity on equipment is also supposed to be in regard. On common conditions, the scandium content in mineral raw material is low, even Sc concentrate of specimen-Yunnan rare earth ore which contain Sc used in this experiment only is 148 g/t. Moreover, in enlarging scale experiments the content of scandium in leach liquid is only 3.6g/t, meanwhile various and complicated impurity existing in it. At present, both domestic and abroad has succeed in enriching scandium from vitriol solution, while enriching scandium from hydrochloric acid only has been studied in some minority units, which is not reported to be practical in industry. Therefore, this item offer a new research issue on Sc?s extract, which is as well as the task of this research. Spectrum analysis, chemic component analysis and scandium content have been made in main mineral measurement on rare earth with Sc in the paper. Based on characters of sample, select hydrochloric acid, vitriol and nitric acid as leach reagent and make different blueprints to accomplish the experimental research about selecting leach reagent. In the aspect of rare earth leach scandium leach density is researched, leach liquid to solid rate, leach temperature, leach time, leach granule rate and leach solution. This experiment claims that in the optimal experimental ambience, leach rate of vitriol is 58.18%, the leach rate of nitric acid is 50.73% and the leach rate of hydrochloric acid is 59.34%. Among them, hydrochloric acid has the best effect, therefore this experiment choose it as the leach reagent.

Jan 1, 2014

By T. Tsurata

The accumulation of thorium and/or uranium by various microorganisms from a solution containing thorium and/or uranium at pH 3.5 was examined. Among the species tested, a high accumulation ability for thorium was exhibited by strains of gram-positive bacteria, such as Bacillus megaterium, B. subtilis, Micrococcus luteus, Rhodococcus erythropolis, and actinomycetes, such as Streptomyces levoris. On the other hand, though uranium was accumulated in small amounts from the solution containing both elements by all these microorganisms, actinomycetes, such as S. flavoviridis and S. levoris had relatively high uranium accumulation abilities. In these high performance thorium- and uranium- accumulating microorganisms, S.levoris, which accumulated the largest amount of uranium from the solution containing only uranium at pH 3.5, could accumulate about 300 µmol thorium and 133 µmol uranium per gram dry wt. of microbial cells from a solution containing both thorium and uranium at pH 3.5. After this screening, uranium accumulation using microorganisms isolated from uranium mines, among which some strains of bacteria were found to possess an extremely high uranium accumulating ability. The microbial biomass may thus be considered for use as an accumulating agent for the removal and recovery of uranium that may be present in metallurgical effluents, mine tailings, seawater and other sources. Recently, hundreds of micro-organisms existing in uranium deposits located in North America, Australia, and Japan for their ability to accumulate large amounts of uranium, and found some new strains which accumulated large amounts of uranium, such as Lactobacillus and Bacillus sp. from Japanese and Arthrobacter and Bacillus sp. from the United States uranium deposits. These bacterial strains can accumulate about 2500 µmol uranium per gram dry wt. of microbial cells within one hour. These microbial cells can remove uranium from the uranium refining wastewater with a high efficiency. The accumulation of uranium from a solution (pH 5.8) by microorganisms contained Arthrobacter nicotianee, which is a similar strain mentioned above Arthrobacter sp., was examined. Among the 76 strains of 69 species tested (23 bacteria, 20 actinomycetes, 18 fungi, and 15 yeasts), high uranium accumulation ability was exhibited by strains of the bacteria, A. nicotianae, B. subtilis, and M. luteus. A. nicotianae cells, which showed the best performance, could accumulate about 698 mg uranium (2.58 mmol) per gram dry wt. of microbial cells.

Jan 1, 2014

By Güven Önal, Gülay Bulut, Mustafa Özer, Yunus Emre Benkli, Olgaç Kangal, Mustafa Tarkan

There are various types of natural zeolite deposits in Turkey. Naturally occurring zeolites are excluded from many important commercial applications where uniformity and purity are essential. In this paper, the beneficiation of natural zeolite, taken from western part of Turkey, was investigated. According to X-Ray Diffraction (XRD) and mineralogical studies carried out on the representative ore sample, the natural zeolite was found to be in the forms of clinoptilolite and heulandite. Clinoptilolite forms as a devitrification product of volcanic glass in tuffs. Quartz, clay minerals, orthoclase, plagioclase, biotite, seruzite-muskovite and epidote were observed as impurities. Several types of mineral processing methods were performed in order to remove impurities from the natural zeolite sample to produce high purity zeolite. Gravity separation methods such as shaking table and superpanner were carried out for separating heavy minerals, while high intensity dry magnetic separation was used for discarding magnetic minerals.

Jan 1, 2003

By M. N. Abdusalyamova

The Republic of Tajikistan has large mercury-antimony deposit. The Republic takes the second place in the countries of the CIS by having antimony recourses or the fourth place in the world. Recently, on the mine bottom horizons the resources of gold were found. Gold in the data ore is submitted as nanosize particles. Results of ores enrichment of bottom horizons of Djijikrut deposit are obtained by a method of flotation. The flow sheet includes the rougher flotation, two scavenging flotation and two cleaner flotation. As a result of enrichment of ore, the mercury-antimony concentrate with the contents of 51.5% of antimony and recovery 90.3% from ore with the content of mercury of 3.5% was received. The investigation of thallium, selenium, and tellurium distributions on products of enrichment was carried out. The most effective reagents are a mixture of oksafore and butyl xanthogenate. While applying this mixture of reagents it is possible to refuse of the use of activator - nitrate lead. The behavior of gold is in details investigated during enrichment. To collective flotation concentrate is extracted only 30% of gold. The basic quantity of gold concentrates in tailings of flotation and is not taken by existing traditional methods. The alternative innovative technology of gold extraction was created. Various methods of roasting of a collective mercury - antimony concentrate oxidizing and reducing are investigated. Vacuum distillation of concentrate allocation in serial sublimates mercury and antimony was designed. In the received calcine concentrates gold. At additional roasting of a calcine up to 900°? concentration of gold makes 30.6 g/t. The offered innovational technology in a complex allows to process ores and concentrates unique mercury-antimony?gold bearing raw material. Keywords: ore, concentrate, flotation, cyanidation, roasting, mercury, antimony, gold

Sep 1, 2012

By Yu. E. Emelyanov, A. V. Bogorodsky, R. N. Nabiulin, S. V. Balikov

"The paper describes the results of the study of gold-copper flotation concentrate atmospheric oxidation at different sizes of material, varying oxidation time, with air or oxygen blow. The study showed the low rate of sulphide oxidation during oxidation of flotation concentrate at a feed size (P98 -74 µm). The coppery recovery into solution was 48%; the recovery of gold by subsequent cyanidation reached 86%. Preliminary flotation concentrate grinding to P98 -20 µm provided oxidation of 90% of copper minerals, 80% of arsenopyrite and 15% of pyrite. The gold recovery by atmospheric oxidation of a fine-ground flotation concentrate increased by 59%, from 36% to 95%, the NaCN consumption reduced by 21 kg/t, from 30 to 9 kg/t. INTRODUCTION Processing of sulphide gold-copper ores and concentrates using conventional cyanidation technology results in higher reagent consumption and lower gold recovery. Destruction of sulphide minerals and extraction of copper from a processed product prior to cyanidation is essential for improving efficiency of precious metals recovery and reducing main reagents consumption. Atmospheric oxidation (AO) is one of the most promising hydrometallurgical methods of refractory gold-copper concentrates processing, along with biooxidation and pressure oxidation. The nature of this approach lies in oxidation of sulphides at 90-95°C, in acidic or alkaline conditions, with bubbling of oxygen or air, after preliminary ultrafine grinding (1-4). The following reactions of sulphide oxidation occur during atmospheric oxidation of a gold-copper flotation concentrate. Pyrite is oxidized with the formation of ferric sulphate (1) and elemental sulphur at low temperatures (2), whereas some portion of elemental sulphur reacts to form sulphuric acid: FeS2+3,75O2+0,5H2O=0,5Fe2(SO4)3+0,5H2SO4; ?G=-1144,02 kJ/mol (1)"

Jan 1, 2018

By R. Kobialka

In the article results of experiments over jaws? linings in jaw crushers with different shaping of working surface were presented. Following sets of jaws were under investigation: immobile plain jaw and moving jaw with grooving surface. Grooving jaws have groves with circular, triangular and trapezoid cross section. In order to evaluate efficiency of comminution both the grain composition of product and the content of irregular grains were determined, as well as the size of crushing forces and process efficiency were measured. For the combination: plain jaw with grooved one, a good results were obtained as regards the grain composition of product and the content of irregular grains. Crushing forces were higher at crushing with mixed types of jaws (the one plain, the second grooved), in comparison to crushing with using both grooved jaws. Efficiency of the process was definitely higher for mixed jaws.

Jan 1, 2014

By B. K. Saikia

A preliminary attempt has been made to study the particle size distribution (PSD) of minerals in one of the industrially important pulverized Indian coal sample using computer-controlled scanning electron microscopy (CCSEM). The results show that clay minerals, quartz, pyrite, and pyrrhotite form the bulk of the mineral matter. Minor minerals, such as calcite, dolomite, ankerite, barite, oxidized pyrrhotite, and gypsum are also observed in the coal sample. The PSD of the included minerals is generally observed to be finer than that of the excluded ones in the coal. Thus, the coal rich in included minerals has more small mineral particles, which may affect its reactivity. The proportion of included to excluded is found to be higher in major cases. Si is found to be mostly occurred as quartz and clay minerals, while Al mostly occurs as silicate minerals. Fe is primarily present as iron sulfides, iron oxide, and Fe-Al-silicate. S is partitioned into iron sulfides and gypsum. Most Ca occurs as carbonates and gypsum, with a minor fraction associated with clay minerals. Mg is found to be mainly present as dolomite and clay minerals, with a very minor fraction present as ankerite. The majority of alkali elements are associated with aluminosilicates. P is mostly associated with kaolinite and/or present as more complex compounds containing Al, Si, and other elements as apatite are found to be absent in the coal studied. Ti is mainly present as rutile and kaolinite. The geo-chemical association of the trace elements has also been discussed. Keywords: minerals, Assam coals, Indian coals, CCSEM study

Sep 1, 2012

By Y. C. Liu

Arsenic bearing copper-gold ores deposit have been found in most areas of China, especially in southwest. Due to the very closed association between arsenic, copper and gold, conventional flotation and cyanide leaching process may not give positive results. An arsenic bearing copper-gold ore in Sichuan province ,with gold grade of 10.12 g/t, 0.6% Cu and 0.14% As, is characterized by superfine grains with -40 microns fraction accounting for 70.9% and the gold enwrapped mainly by pyrite and tennanite accounts for 34.31%. Arsenic in this ore occurs in isomorphism, deposited in tetrahedrite. The ore was processed primarily in two stage flotation to get copper bearing gold concentrate and pyrite bearing gold concentrate respectively, and sequentially processed by leaching. Under the pressure of 300 KPa and 110~115 ?, the copper-gold concentrate was leached by an oxidizing and catalyzing leach agent then copper and gold were separated from each other in leach solution. The pyrite bearing gold concentrate was processed by cyanide leaching with the leach residue as sulfur product. The test results showed that copper recovery was up to 88.89%, gold recovery up to 89.18% and sulfur recovery up to 92.64%.

Jan 1, 2014

By Willis Forsling, Prabhakar Swarna, Hanumantha Rao Kota

The solubility of wollastonite and its Hallimond flotation behavior as a function of dodecylamine concentration and pH are examined. The flotation response is characterized by adsorption and surface energy in the presence of amine. The methods of UV-Visible and FT-IR spectroscopy for adsorption and sessile-drop contact angle for surface energy estimation are employed. The results of wollastonite dissolution clearly showed its non uniform dissolution. The surfaces are depleted with calcium ions and became rich in silicon within 10 min of flotation time. Maximum flotation of wollastonite corresponds to a half monolayer coverage of amine, which is substantiated by the surface energy parameters. A good correlation between flotation, adsorption and surface energy as a function of amine concentration and pH was observed. The sudden increase in wollastonite flotation and amine adsorption at and above 5x10-5 M initial amine concentration is thought to be due to two-dimensional precipitation of amine on surface in accordance with the recent 2D-3D precipitation model of amine adsorption on silicate minerals.

Jan 1, 2003

By A. Boulton

Low molecular weight synthetic polymers substituted with hydroxyl, carboxyl or sulfonate functional groups were used to improve the flotation separation of zinc or copper sulfide minerals from iron sulfide gangue minerals in three massive sulfide ores of different mineral composition. These polymers produced significant improvements in zinc or copper grades as a result of a selective depression of iron sulfide minerals. It was shown that this selectivity was the result of preferential adsorption of the polymer on the surface of the iron sulfide minerals. The different types of interaction between the functional group on the polymers and the sulfide mineral surfaces could explain the trends observed in the flotation results.

Jan 1, 2003

By X. Tan

In this paper, the application of the metallurgical residue produced from oceanic cobalt-rich crusts leaching process is studied in the area of wastewater treatment. The modification of the sulfuric acid leached residue and the adsorption behavior behaviour of heavy metal ions such as (Pb(II), Cu(II), Zn(II), Cd(II), Ni(II), Mn(II), Co(II), As(III)) in the waste-water on the surface of the residue are investigated. The rate of adsorption efficiency of heavy metal ions in the wastewater on the modified sulfuric acid leached residue is investigated. It is showed that when the initial pH value of wastewater containing heavy metal ions including Pb(II), Cu(II), Co(II), Ni(II), Mn(II), Zn(II), Cd(II) and As(III) range from 1.4 to 1.9, with the use of the modified leached residue, As(III) ion can be selectively separated from wastewater, and the separation efficiency can reach 90%~100%. The adsorption efficiency is affected by pH, reaction time, amount of adsorbent and the initial concentration of heavy metal ions in wastewater. The results showed that the optimum pH was natural pH value and the absorption equilibrium time was 2 hours. The adsorption efficiency of heavy metal ions increases with the addition of adsorbent and de- creases with the increase of the initial concentrations of heavy metal ions in wastewater. The heavy metal ions polluted wastewater, of which concentration is about 22.5~793.6 mg/L, can meet the national disposal standard for industrial wastewaters in China very well, after 2 hours treated by 3.75~7.50 g/L modified adsorbent at room temperature. Standard methods were used to investaged investigate the absorption behaviour between abosorbentabsorbent and metal ions in the wastewater. It is concluded that the adsorption behaviour of Co(II), Mn(II) and As(III) ion fits Freundlich iso-therm, while the adsorption behaviour of Pb(II), Cu(II), Zn(II), Cd(II) and Ni(II) ions fits Langmuir isotherm, and the saturated adsorption amount of the modified adsorbent is about 54.0~336.7mg metal/g?adsorbentabsorbent. It is suggested that the modified sulfuric acid leached residue produced from oceanic cobalt-rich crusts is environmentally attractive and meaningful as absorbent used in heavy metal ions polluted wastewater.

Jan 1, 2014

By Y. Q. He

The dynamic behaviors of the air bubbles in the dense gas-solid fluidized bed have a significant effect on the performance of dry coal separation. The combined method of experimental measurement and numerical simulation were conducted to conduct the research of the mean diameters and rising velocities of the bubbles in the fluidized bed. The calculation models of mean diameter and rising velocity of the single bubble were proposed. The results indicate that the models of the mean diameter raised by Rowe (1976) and the rising velocity raised in this work could be used to predict the bubble dynamic parameters in gas-solid fluidized bed. With the Geldart B type of magnetite powder as the medium solids and while the gas velocity of 1.5Umf=U=2.2Umf, the mean bubble diameter along the bed height is 36mm<Db<45mm, and the mean rising velocity of the single bubble is distributed in 40~65cm/s. The results of experimental measurement, numerical simulation and model predication provide well agreements finally. Based on the uniform fluctuations of air bubbles diameters and their rising velocities, the separation experiments of 50~6mm dry coal using the mixture of 0.3~0.15mm magnetite powder and <1mm fine coal as medium solids were carried out. The results show that the probable error, E is 0.06, which indicates a good separation performance by using the gas-solid fluidized bed. Keywords: dense gas-solid fluidized bed, bubble dynamic behaviors, numerical simulation, separation performance

Sep 1, 2012

By N. Acarkan

Beneficiation of the pyrite concentrate of the Kastomonu-Küre (Northern Turkey) copper ore seems to be attractive due to its high Cu, Co, and Zn contents. Pyrite concentrate were used in the experimental studies. Cu, Co, and Zn were recovered from the concentrate by the sulphatizing roasting, leaching and the precipitation using H2S. Sulphatizing roasting experiments were carried out in a rotary furnace and the optimal roasting conditions were found to be at 650°C roasting temperature and 3.0 h roasting period and addition of Na2SO4 of 3 % for the concentrate containing 0.58% Cu, 0.22% Co, and 0.04% Zn. Then, the roasted product was repeatedly leached with 10 g/L H2SO4 solution. Optimal conditions were found to be 60 oC leaching temperature, 2 h leaching period, and 30% pulp density. Leaching efficiencies for Cu and Co were over 99 %. The valuable metals in the pregnant solution were selectively precipitated by H2S as sulfides. Selective precipitation of Cu, Zn, Co was achieved by adjusting the pH and the temperature of the leach solution. Final metal recoveries of 99.20% Cu, 99.40% Co, and 95.60% Zn were attained. The precipitated sulphides are marketable products. Roasting gases with their 15% SO2 content are suitable for the production of H2SO4 and the leach residues can be integrated with the iron ore processing plant as they contain 57.50 % Fe, 17.70% gangue (SiO2, CaO, etc.), 0.04% S, and 0.06% non-ferrous metals.

Jan 1, 2014

By J. Y. Tian

In view of the fact that many domestic iron ore-dressing plant applying flotation cells in the re-verse flotation, to improve the technical level of magnetite reverse flotation, we apply such a technological process of one stage rougher and two stages scavenger flotation column respectively. The middling from the two stage scavenger process are returned to magnetic separation for condensing. By contrast, the technological process of one stage rougher and one stage cleaning flotation cells is made up of by multi-magnetic separation and magnetic middling regrinding separations. It has been proved that the flotation column we offer can simplify the technological process structure, obtain advanced technical indexes, run the system smoothly, reduce energy consumption, and be environ-mental friendly.

Jan 1, 2014

By Y. De Gao, C. Gang Zhong, X. Yang Qiu, Li Wan

The chelating reagents are used as effective collectors in wolframite flotation, and certain metal cations need to be added using chelating collectors so as to activate valuable minerals and obtain good flotation indexes. Different metal cations will result in different reactivity with collectors, in order to select the effective activator in BHA flotation of wolframite, the activation effectiveness of different metal cations on wolframite ((Fe,Mn)WO4) flotation were studied using pure minerals. The results showed that the wolframite activation by Pb2+was the best among the selected cations. The maximum flotation recovery of wolframite was found to be 95.58 % under conditions of 100mg/LBHA and 1×10-4mol/L of Pb2+at pH 9. The dosage of Pb2+needs to be controlled in an optimum range. Also, the activation mechanism of Pb2+ on BHA flotation of wolframite was investigated by measurements of contact angle, zeta potential, adsorption capacity and IR spectroscopy. It was found that Pb2+ could chemically adsorb onto the wolframite surface improving the flotability of wolframite and enhancing the adsorption of BHA on wolframite. When the dosages of BHA and Pb2+ were 100 mg/L and 1×10-4 mol/L, the adsorption quantity of BHA on wolframite sharply increased up to 0.30 mg/L at pH 9 compared with wolframite treated with only BHA.

Jan 1, 2014