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By Andrzej Luszczkiewicz, Magdalena Duchnowska, KGHM Polska Miedz S. A., Witold Pawlos, Jan Drzymala, Alicja Bakalarz, Przemyslaw B. Kowalczuk

Numerous data in the literature confirm that the chemical composition and consumption of grinding media influence electrochemical properties of flotation suspension as well as effectiveness and selectivity of upgrading processes. During a milling process, attrition of grinding media is observed. Depending on the susceptibility to abrasion, the grinding media influence, to a different extent, the redox potential, pH as well as flotation efficiency. As a result, different upgradeability of sulfide minerals is observed. The paper presents laboratory scale flotation results, obtained for the copper sulfide ore from Polkowice Region of KGHM Polska Miedz S.A. in Poland ground in the presence of forged steel, highchrome iron and stainless steel as the grinding media. The investigated flotation feed contained 36 g/t (ppm) of silver and 1.86 % of copper. Several flotation tests were conducted using fixed amount of frother and a mixture of sodium ethyl and isobutyl xanthates as the collector at three different doses of 75, 100 and 125 g/t. A comparison of the obtained results confirmed that the application of grinding media with different chemical compositions influenced the electrochemical properties of the suspension and recovery of silver and copper in the final concentrate. The highest values of redox potential were observed for the stainless steel as the grinding medium. Moreover, in the presence of this type of grinding media, regardless of the collector dosage, the best silver upgrading was observed. For the forged and high-chrome iron media, the recovery of silver depended on the collector dosage. It is indicated that higher levels of the redox potential, together with smaller amount of iron released from the grinding medium, improve the flotation of the silver-bearing mineral compounds from the copper sulfide ore.

Jan 1, 2016

By W. K. Tolley, D. G. Kotlyar

Silver is an economically important component of many complex, massive sulfide ores. The beneficiation of this type of ore is now almost entirely accomplished by flotation. Silver recovery is often low, and little is known about the flotation behavior of the silver-bearing minerals. Floatability studies were conducted using silver-bearing tetrahedrite and lead-zinc ore. The effects of xanthate-collector concentration, conditioning time, potentiostatic control of the mineral potential and control of the pH on mineral floatability were evaluated. The floatability of the silver-bearing minerals was shown to depend on collector concentration and mineral potential. The effect of controlling the mineral potential during the flotation process is discussed.

Jan 1, 1996

By D. G. Kotlyar

Silver is an economically important component of many complex, massive sulfide ores. Current beneficiation for these ores is almost entirely by flotation. Silver recovery often is low, but little is known about the flotation behavior of the silver-bearing minerals. Floatability studies were conducted using silver-bearing tetrahedrite and lead-zinc ore. The effects of xanthate collector concentration, conditioning time, potentiostatic control of the mineral potential, and pH on mineral floatability were evaluated. The floatability of the silver-bearing minerals was shown to depend on collector concentration and mineral potential. The effect of controlling mineral potential during the flotation process is discussed.

Jan 1, 1994

Flotation of Smithsonite by Using Siloxane Cationic Surfactants as Collectors

Sep 13, 2010

The flolation behaviour of some Australian uranium ores was investigated. Although uraninite and pitchblend float readily with fatty acids, selective concentration to produce an economically discardable tailing has not yet been achieved. This is attributed to the presence in the ores of a quantity of uranium mineral in finely dispersed form which is very difficult to liberate. For some of the ores, at least, the proportion of this material decreases with increase in head assay.Flotation may be a useful concentrating method for some Australian ores if uranium oxide is to be sold in a free competitive market.

Jan 1, 1967

By Geoffrey Purcell

The flotation response to amine collector of quartz and the feldspars microcline and albite, of the pyroxenes augite and spodumene, and of olivine can be, explained by a physical adsorption model. Flotation decreases in the order given above, and the different behavior of the three groups is attributed to structural variations of the silicates, With sulfonate collector both chemical action and physical adsorption play their part in producing hydrophobic surfaces, and flotation increases in the order given.

Jan 1, 1966

The recovery by flotation of some complex uranium minerals such as brannerite and davidite is described. Anionic reagents used for flotation of iron and titanium oxides' are suitable. If care is taken, to emulsify the reagents the slime fractions may be satisfactorilytreated.INTRODUCTIONUranium ores are usually treated by direct leaching with acid or alkali according to the nature of the gangue materials. Concentration of the uranium minerals prior to leaching is not commonly practised because of the earthy nature of most uranium minerals and the difficult mineral dressing problem they pose. Some of the harder complex oxides such as davidite and brannerite are amenable to flotation. This is fortunate since they usually require an expensive, strong acid treat~ent to dissolve the uranium. Flotation tests were commenced in 1949 by officers of the South Australian Department of Mines stationed at Adelaide, first in the School of Mines, then in the University of Adelaide and finally in Departmental mineral dressing laboratories at Thebarton. Separation of daviditefrom Radium Hill and Mount Victoria ores, brannerite from Crocker's Well ore, and secondary uranium minerals from Myponga ore was attempted.The development of the flotation reagents to separate the oxides from silica and the silicates is first described, then some of the results obtained are presented as tables.DEVELOPMENT OF FLOTATION REAGENTSThe davidite at Radium Hill is associated with iron and titanium oxides, qu;a,rtz and biotite as replacement deposits in shears. The davidite, rutile,' ilmenite and hematite usually occur in segregations from nut size to masses of several pounds. They are associated as a complexity of...

Jan 1, 1955

By James S. Browning

Extensive deposits of kyanite occur in the southeastern United States, The reserves of these deposits, if developed, are adequate to supply the United States with 35-mesh kyanite concentrate:; for many years at the present-rate of consumption, According to Espenshade and Potter,1 the kyanite-quartz rock type deposits in this area contain about 100 million tons of ore averaging 10 to 30 percent kyanite. The tonnage of kyanite-bearing gneiss and schist is, much larger than the tonnage of kyanite-quartz rock, but the kyanite gneiss and schist are appreciably lower in grade. The largest deposits of kyanite-quartz rock are in the Farmville district, Virginia, and Kings Mountain district, North Carolina South Carolina, and at Graves Mountain, Georgia. Of the known deposits, only four were being mined for kyanite in 1967. These deposits are near Farmville and Dillwyn, Va., Clover S. C., and Washington, Ga. Production of kyanite and synthetic mullite increased substantially in 1965.2 Output of, domestic kyanite concentrate increased by 14 percent in 1965, establishing a record high for the fifth consecutive year. Estimated annual consumption of kyanite minerals and synthetic mullite was in excess of 100,000 tons. The manufacture of mulatto refractories accounts for most of the kyanite minerals consumed annually, but non-refractory uses are expanding.3 Most mullite refractories are used as furnace linings in metallurgical and glass manufacturing furnaces. The remainder is used largely for kilns, kiln furniture, and saggers by the ceramic industry. Small quantities of kyanite without calcination are used as a source of alumina in the manufacture of glass, electrical and chemical, porcelain, pyrometer tubes, and in the form of kyanite concentrate to increase the alumina content of fireclays. Kyanite is used to improve workability, increase strength, and to compensate for firing shrinkage in floor and wall tile and other ceramic products.

Jan 1, 1968

By S. Meng, R. Jin, W. Hu

In alkaline pulp, galena is depressed by sodium carboxymethyl cellulose (NaCMC), while Cu(II) -activated sphalerite exhibits a high floatability so that satisfactory separation can be achieved. In addition to hydrogen bonding, chemical bonding of NaCMC with galena is confirmed by infrared (IR) spectra; only hydrogen bonding is involved between NaCMC and Cu(II)-activated sphalerite. It is also found that the greater the degree of substitution and polymerimtion of NaCMC, the stronger the depressive effect of NaCMC and that lower stirring speed favors the depression.

Jan 1, 1988

By Ruiren Jin

In alkaline pulp, galena is depressed by sodium carboxymethyl cellulose (NaCMC), while Cu(II)-activated sphalerite exhibits a high flotability so that satisfied separation can be achieved. In addition to hydrogen bonding, chemical bonding of NaCMC with galena is confirmed by IR; only hydrogen bonding is involved between NaCMC and Cu(II)-activated sphalerite. It is also found that the greater the degree of substitute and polymerization of NaCMC, the stronger the depressive effect of NaCMC and that lower stirring speed favors the depression.

Jan 1, 1987

By J. S. Browning

The pegmatites of the Kings Mountain-Lincolnton, N. C., area constitute the largest known domestic reserve of beryl and spodumene. The reserve is estimated to contain 90 million tons of pegmatic material with 1,280,000 tons of recoverable Li2O (lithia) as spodumene.1 The pegmatites also contain 0.4 to 0.5 pct beryl disseminated throughout the orebodies. The pegmatites may contain a potential reserve of 240,000 tons beryl, equivalent to approximately 34,000 tons of BeO. Different flotation methods for separating beryl from feldspar or quartz, or both, have been developed by various investigators.2,3,4,5,6,7 On the other hand, published information is limited on concentration of spodumene-beryl ores. As the response of beryl and spodumene to flotation is essentially the same, a successful separation of the two minerals depends upon use of a selective depressant or a selective collector for one of the minerals.

Jan 7, 1961

By O. Ofor

Coal fines of less than 0.5 mm particle size, discarded as too fine for gravity separation, were subjected to flotation tests at varying pH and temperatures using modified dosages of kerosene as oil phase and methylisobutylketone (MIBK) as frother. Optimal coal recovery of over 74% was obtained using 200 kg kerosene and 4 kg MIBK per ton of coal fines at a pH of 9.7 and an ambient temperature of 26° C. The coal concentrate obtained under these optimal recovery conditions assayed 9.10% ash, 0.35% sulfur and 0.011% phosphorus, representing reductions in the ash, sulfur and phosphorus contents of approximately 75%, 43% and 8.3%, respectively. Its gross calorific value was 32.9 MJ/kg, its percentage of volatile matter measured 30.6 and the fixed carbon content was 66.3% (d.a.f). Caking tests showed the optimal concentrate has a standard welling number of 1 and is a Gray-King coke type C. These results show that the optimal flotation product could be utilized for such industrial purposes as steam raising or for processing in gasworks, but it would be unsuitable for metallurgical coke production.

Jan 1, 1993

By X. M. Yuan

In the flotation of Zn-Pb ores, sphalerite is floated following copper sulfide activation. In this type of sulfide ore, pyrite is commonly treated as a gangue, and poor selectivity between sphalerite and pyrite/quartz is often reported. But pyrite may also appear in association with gold, and flotation of such auriferous sulfides is of great importance in many countries (e.g. South Africa, Australia). In the cationic flotation of sulfide ores with dodecyl amine, sphalerite can be floated while depressing quartz and pyrite. While in a well-aerated pulp in the presence of lime (especially after oxidation with H2O2) the cationic flotation of pyrite is depressed, oxidation of pyrite in the presence of Na2S makes it floatable with amines even in very alkaline environment.

Jan 1, 2002

By Corneille S. Ek

Flotation of several copper and lead-zinc ores has been carried out with mercaptobenzothiazole (MBT) as promoter. The results of laboratgory batch flotation tests have been compared with those obtained when using more common collectors like xanthates or dithiophosphates. It generally appears that MBT is an effective collector of all the sulfides, including pyrite, but that high selectivity is rather difficult to attain, except for gangue drop-out. Some kinetic tests have been performed to check the froth production rate by MBT as compared to other collectors.

Jan 1, 1995

By M. C. Furerstenau

Adsorption behavior of various surfactants on sulfide minerals is very much affected by the nature of the surface of the mineral. Since sulfides are naturally meta-stable, oxidation occurs when they are exposed to air, especially in aqueous environments. As a result. oxygen assumes a major role in sulfide flotation. Mechanisms of adsorption of various thiol collectors on sulfide minerals have been reviewed. The electrochemical behavior of various sulfide minerals has also been reviewed. Flotation behavior of galena, chalcocite, sphalerite, pyrite, chalcopyrite and pentlandite has been presented together with the. flotation of copper sulfide- nickel sulfide ore.

Jan 1, 1993

By V. V. Zakopaylo, M. V. Lukyantseva, V. A. Ignatkina, V. A. Bocharov, L. C. Khachatryan, D. M. Altynamanov, A. A. Kayumov, R. H. Sharipov

"This research was aimed to explain the reasons of low floatability of tennantite from refractory pyrite ores of non-ferrous metals and to create a reagent regime for selective increasing a recovery of copper sulfide minerals from arsenic-containing copper pyrite ore. ?opper-zinc ore of the Uzelga deposit has 89% of pyrite, some part as melnikovite; copper is assayed as 3.58% of tennantite and 0.25% of chalcopyrite; there is 2.19% sphalerite. Sulfide minerals are very finely disseminated. Tennantite is genetically related to primary copper sulfides. Graphene was identified on the surface of tennantite by a transmission electron microscopy (TEM) method. The recovery of tennantite was rose up by using the collector M-TF. M-TF is the mixture of diisobutylditiophosphate (DTF) and O-isopropyl-N-methyl (ethyl) (TC) in the certain ratio. M-TF change up a kinetic of copper sulfide flotation in a slightly alkaline medium, but pyrite has slowly floatability at this moment. A depressing effect of thiosulfate ions in a liquid phase of pulp flotation tennantite from pyrite ore has been established. A copper recovery up 14.2% (from 67.7 to 82.0%) into a copper concentrate level off copper grade of 18.65% (butkx) and 18.68% (M-TF) has been increased by the new technology with M-TF compared to a standard technology with butkx. A main copper recovery up to 50 % in an inter-cycle copper concentrate assaying 19-21% Cu in case of using M-TF was gotten. A zinc concentrate with recovery of 50% and a zinc assay of 41.76% by a standard flow sheet with butyl xanthate was obtained. A zinc recovery of 70.3% with a zinc grade of 44.17% by the M-TF technology was achieved.INTRODUCTION The pyrite copper-zinc ores of the Urals region are considered refractory. The distinctive features of these ores include a high content of pyrite (90-95%), the presence of arsenopyrite and arsenical pyrite, and the simultaneous presence of chalcopyrite, bornite, tennantite with the predominance of the latter (Andreasen et al.,2008;.Dobrotsvetov, 2009; Chanturiya et al. 2016). The flotation properties of tennantite differ from those of chalcopyrite (Xumeng Chen, Yongjun Peng, Dee Bradshaw. 2014), which is the reason why a comprehensive study was under taken of the flotation activity of tennantite and a process for its recovery was developed. The proposed agent treatment and flotation process make it possible to produce salable copper and zinc concentrates."

Jan 1, 2018

By A. R. Barnes, N. O. Lotter

Recoverable economic copper sulphide minerals such as chalcopyrite, bornite, chalcocite and covellite often occur together in varying proportions in the major copper-bearing ores, and have individual flotation requirements and characteristics. Pyrite also occurs in these ores to varying extents as the sulphide gangue, and is problematic because of its natural tendency to float quickly and easily. In a bulk sulphide float, selectivity against pyrite is desirable, particularly if it does not host other paymetals such as gold or silver. At the same time it is a requirement to float all of the copper sulphides despite their electrochemical differences. The electrochemistry and semiconductor properties of these minerals are reviewed, together with implications for flotation with and without collector addition. Mixed collector systems for the improved flotation of these sulphides are proposed as a solution. The use of xanthate and dithiophosphate in the collector suite allows the co-existence of dixanthogen and free dithiophosphate radical because the latter has a higher redox potential requirement than xanthate to oxidise to the dithiolate. Because some of these minerals require dixanthogen, and others, free thiolate, to generate surface hydrophobicity, a bulk flotation of all the species becomes possible in the overlapping area of Eh and pH between the two dithiolate equilibrium lines on the Pourbaix diagram. The arsenic-signature copper minerals are added to the study, since many copper operations encounter arsenic as a penalty element in the saleable concentrate. It is shown that the addition of arsenic to the copper and iron sulphides alters the semiconductor and electrochemistry properties, and in turn, its flotation characteristics. The degree of mineral association and liberation between these minerals can be a complicating factor due to textural associations, and should also be considered in the process as a next step.

Jan 1, 2016

By M. A. D. Azevedo

The effect of pulping reagents on the flotation de-inking of laser printed wastepaper was investigated with regard to the removal efficiency of toner and mineral filler particles for different pH values. These results show that caustic pulping causes the toner to be released from the fibers at larger particles sizes. On the other hand, acid pulping not only causes the toner to be released at smaller particles sizes but also increases the concurrent flotation removal of mineral filler particles. It was experimentally observed that the froth generation and stability during flotation were improved for acidic pH values.

Jan 1, 1997

By W. D. Eddy

Topaz is a fluorine-bearing aluminosilicate mineral of the kyanite-sillimanite group. The formula has been given as Al2SiO4(F,OH)2, [Al(F, OH)]2SiO4, or 2Al2O3?2Al(F, OH)3SiO2. Topaz is generally considered a semiprecious-to-precious gem mineral, but it is a fairly common minor constituent of granites. In 1937 the U.s. Geological Survey reported an occurrence of massive topaz in the 3 Brewer gold mine, Chesterfield County, S.C. Over the next 8 years considerable research was done on topaz to establish its properties and to determine possible end uses The first reported shipment of ore was in 1939 Peak production was reached in 194412, and output then began declining until the mine closed in 194913? During World War II topaz was used in refractories, as a flux in steel mills, and in the manufacture of borosilicate glass 14. The main advantage of using topaz over kyanite and sillimanite in refractory use was that calcined topaz converted to over 95 percent mullite (3A1203 .2Si02) while calcined kyanite or sillimanite contained only 88 percent mullite15. However, a major draw-back to utilization of topaz is the evolution of fluorides during calcination. In 1973 the Geological Survey reported that topaz occurred in probable commercial quantities in at least two domestic locationsl6: the Brewer area of South Carolina and a location in Colorado. The literature also indicated that progress had been made in controlling fluorine-bearing fumes. This research has progressed to the state where valuable fluorine compounds are being recovered on a commercial scale 17. Thus, a major obstacle to utilization of topaz appears to have been resolved. The Bureau of Mines under its program of advancing minerals technology initiated a project to study techniques for the concentration of topaz from disseminated materials. The objective of the study was to determine those techniques that would be used to produce topaz concentrates that could be utilized as a source of fluorine and mullite.

Jan 1, 1977

By L. Zeng, Q. Feng, Z. Qiu, L. Ou, Central South University

It is well-known that the use of nanobubbles can significantly improve the flotation efficiency of ultra-fine particles. However, this is mainly focused on coal and phosphate rock flotation. In the field of nonferrous metal processing, the related research is few. In this paper, a small laboratory mechanical cell associated with a specially-designed nanobubbles generator was used to investigate the effects of nanobubbles on enhancing ultra-fine scheelite flotation. Nanobubbles were created and based on the hydrodynamic cavitation principle through Venturi tubes. Comparative flotation tests were performed using different tubes to evaluate the nanobubbles impact on the ultra-fine scheelite particle flotation recovery. In order to better understand the nanobubbles enhanced ultra-fine scheelite flotation, nanobubbles potential and size distribution were measured. The effect of nanobubbles on the particle aggregation and scheelite particles potential were also studied through the turbidity tests, microscope tests and zeta potential measurements. According to the results, the mean size of nanobubbles was about several hundred nanometers, and the surface of nanobubbles was of highly negative charge in alkaline conditions. The flotation recovery of ultra-fine scheelite particles was increased in the presence of nanobubbles. The zeta potential measurements indicated that the repulsive forces between scheelite particles decreased when nanobubbles existed. Through the turbidity tests and microscope tests, the promotion effect of nanobubbles on particle coagulation could be verified more directly. The existence of nanobubbles in flotation system promotes the particle aggregation, thus increasing particles apparent size and particles capture by bubbles, which may be the fundamental reason why nanobubbles enhance ultra-fine scheelite flotation.

Jan 1, 2016