Role of calcium and magnesium cations in the interactions between kaolinite and chalcopyrite in seawater
More details
Hide details
1
Water Research Centre for Agriculture and Mining (CRHIAM), Universidad de Concepcion, Chile
2
Departmento de Ingenieria Metalurgica, Department of Metallurgical Engineering, Universidad de Concepcion, Chile
3
N.B. Keevil Institute of Mining Engineering, University of British Columbia, Canada
Publication date: 2017-02-20
Corresponding author
Leopoldo Gutierrez
Departmento de Ingenieria Metalurgica, Department of Metallurgical Engineering, Universidad de Concepcion, Chile, Edmundo Larenas 285, 4070371 Concepción, Chile
Physicochem. Probl. Miner. Process. 2017;53(2):737-749
KEYWORDS
TOPICS
ABSTRACT
A number of flotation plants around the world have increased the use of seawater due to limited sources of fresh water. The aim of this research work is to study the role that Mg2+ and Ca2+ ions play in the interactions between kaolinite and chalcopyrite in seawater. In order to achieve this objective, the effect of kaolinite on flotation of chalcopyrite is studied over the pH range from 8 to 11, when flotation is carried out in seawater and in a 0.01M NaCl solution. The influence of calcium, magnesium, sodium, and potassium ions on the extent of depression by kaolinite is evaluated. The micro-flotation results indicate that chalcopyrite is depressed by kaolinite in both 0.01 NaCl solution and seawater. In the 0.01 NaCl solution, the depressing effect of kaolinite decreases as the pH increases from 8 to 11. However, the results obtained using seawater show that the depressing effect of kaolinite is similar to what is observed in a 0.01 NaCl solution only at pH values below 9, but above this pH kaolinite significantly affects the recovery of chalcopyrite. The results from experiments with using solutions containing individual cations show that the depressing action of kaolinite in the presence of Mg2+ and Ca2+ is more obvious at pH values of 9 and 10, respectively, which correlates with the pH values at which the first hydroxy-complexes of these divalent cations start forming. This seems to indicate that depressing effect of kaolinite on chalcopyrite in seawater may be related to formation of hydrolyzed species of calcium and magnesium. These species can induce heterocoagulation between kaolinite and chalcopyrite. The trends observed in the micro-flotation experiments are in good agreement with the results of the induction time measurements and slime coating tests.
REFERENCES (24)
1.
BRUCKARD W.J., SPARROW G.J., WOODCOCK J.T., 2011, A review of the effects of the grinding environment on the flotation of copper sulphides, International Journal of Mineral Processing, 100, 1-13.
2.
CASTRO S., LASKOWSKI J.S., 2011, Froth Flotation in Saline Water, KONA Powder and Particle Journal, 29, 4-15.
3.
CASTRO S., RIOSECO P., LASKOWSKI J.S., 2012, Depression of molybdenite in sea water, XXVI International Mineral Processing Congress-IMPC 2012, New Delhi, India, September 24-28, pp. 737-752.
4.
CASTRO S., URIBE L., LASKOWSKI J.S., 2014, Depression of inherently hydrophobic minerals by hydrolysable metal cations: molybdenite depression in seawater. XXVII International Mineral Processing Congress-IMPC 2014, Flotation Chemistry Chapter, Santiago, Chile, October 20-24, 2012, pp. 207-217.
5.
CHIPERA S.J., BISH D.L., 2001, Baseline studies of the clay minerals society source clays: powder X-Ray diffraction analyses, Clays and Clay Minerals, 49 (5), 398-409.
6.
EKMEKCI Z., DEMIREL H., 1997, Effects of galvanic interaction on collectorless flotation behaviour of chalcopyrite and pyrite, International Journal of Mineral Processing, 52, 31-48.
7.
FORBES E., DAVEY K.I., SMITH L., 2014, Decoupling rheology and slime coatings effect on the natural floatability of chalcopyrite in a clay-rich flotation pulp, International Journal of Mineral Processing, 56, 136-144.
8.
FRANKS G., 2002, Zeta potentials and yield stresses of silica suspensions in concentrated monovalent electrolyres: Isoelectric point shift and additional attraction, Journal of Colloid and Interface Science, 249, 44-51.
9.
FUERSTENAU M.C., PALMER B.R., 1976, Anionic flotation of oxides and silicates. In: Flotation A. M. Gaudin Memorial Volume (M.C. Fuerstenau, Ed.), AIME, 1, 148-196.
10.
HEYES G.W., TRAHAR W.J., 1979, Oxidation–reduction effects in the flotation of chalcocite and cuprite, International Journal of Mineral Processing, 6, 229–252.
11.
JAMES R.O., HEALY T.W.J., 1972, Adsorption of hydrolysable metal ions at the oxide–water interface, Part I, Journal of Colloid and Interface Science, 40, 42–81.
12.
JOHNSON S.B., FRANKS G.V., SCALES P.J., BOGER D.V., HEALY T.W., 2000. Surface chemistry – rheology relationships in concentrated mineral suspensions, International Journal of Mineral Processing, 58, 267-304.
13.
KELM U., HELLE S., 2005, Acid leaching of malachite in synthetic mixtures of clay and zeolite-rich gangue. An experimental approach to improve the understanding of problems in heap leaching operations, Applied Clay Science, 29, 187-198.
14.
KELM U., HELLE S., JEREZ O., PINCHEIRA M., 2013, What are copper clays? Geometallurgical implications, Copper international Conference (COPPER 2013), Santiago, Chile, December 1-4.
15.
LASKOWSKI J.S., 2012, Anisotropic Minerals in Flotation Circuits, CIM Journal, 3(4), 203-213.
16.
LIU J., ZHOU Z., XU Z., MASLIYAH J., 2002, Bitumen–Clay Interactions in Aqueous Media Studied by Zeta Potential Distribution Measurement, Journal of Colloid and Interface Science, 252, 409-418.
17.
OATS W.J., OZDEMIR O., NGUYEN A.V., 2010, Effect of mechanical and chemical clay removals by hydrocyclone and dispersants on coal flotation, Minerals Engineering, 23, 413-419.
18.
RAGHAVAN S., HSU L.L., 1984, Factors affecting the flotation recovery of molybdenite, International Journal of Mineral Processing, 12 (1984) 145-162.
19.
RAN B., MELTON I.E., 1977, Particle Interactions in Aqueous Kaolinite Suspensions: I. Effect of pH and Electrolyte upon the Mode of Particle Interaction in Homoionic Sodium Kaolinite Suspensions, Journal of Colloid and Interface Science, 60(2), 308-320.
20.
REBOLLEDO E., LASKOWSKI J., GUTIERREZ L., CASTRO S., 2016, Use of dispersants in flotation of molybdenite in seawater, Minerals Engineering, 100, 71–74.
21.
SONNEFELD J., GOBEL A., VOGELSBERGER W., 1995, Surface charge density on spherical silica particles in aqueous solutions: I. Experimental results, Colloid and Polymer Science, 273, 926-931.
22.
SWORSKA A., LASKOWSKI J.S., CYMERMAN G., 2000, Flocculation of the Syncrude fine tailings. Part I. Effet of pH, polymer dosage and Mg2+ and Ca2+ cation, International Journal of Mineral Processing, 60, 143-152.
23.
URIBE L., GUTIERREZ L., JEREZ O., 2016, The depressing effect of clay minerals on the floatability of chalcopyrite, Mineral Processing and Extractive Metallurgy Review, 37 (4), 227-235.
24.
WRIGHT H.J.L., KITCHENER J.A., 1976, The problem of dewatering clay slurries: factors controlling filtrability, J Journal of Colloid and Interface Science, 56, 57-63.