THE EFFECT OF SALINE WATER ON THE FLOTATION OF CHALCOPYRITE AND PYRITE
Claudia Aguirre Valdes CSIRO Chile Research Foundation, Chile, PhD student, +56 55 2637313
claudia.aguirre.v@csirochile.cl
Leanne Smith CSIRO Mineral Resources, Clayton, Australia, Senior Experimental Scientist,
+61 3 9545 8667, Leanne.Smith@csiro.au
Graeme Heyes CSIRO Mineral Resources, Clayton, Australia, Honorary Fellow, +61 3 9545 8569,
Graeme.Heyes@csiro.au
ABSTRACT
Given the global scarcity of fresh water, flotation plants, now and in the future, will have to use groundwater or
sea water with a high salt concentration. Previous single mineral laboratory batch flotation tests at pH 9 on
chalcopyrite, bornite and chalcocite have shown that chalcopyrite flotation is unaffected by brackish water, sea
water or hypersaline water compared to distilled water but that both bornite and chalcocite are detrimentally
affected by the use of lower quality waters. The decrease in floatability appeared to be readily overcome by the
addition of collector.
In copper ores, chalcopyrite is often found in association with pyrite and other gangue minerals. This paper
describes a series of flotation tests undertaken on pyrite/quartz and chalcopyrite/pyrite/quartz mixtures to
investigate the effect of water quality on pyrite flotation and the chalcopyrite/pyrite separation. At pH 9, pyrite
flotation with potassium ethyl xanthate is unaffected by the use of different quality waters but at pH 10.5, while
pyrite is moderately floatable in distilled water with collector, it is poorly recovered in hypersaline water under
the same conditions. From the flotation tests on chalcopyrite/pyrite/quartz mixtures, it was found that, at pH
10.5 in the absence of collector, there was a detrimental effect on the flotation behaviour of chalcopyrite in
hypersaline water compared to distilled water. This is in contrast to previous findings in the single mineral tests.
Further tests completed have investigated the possible reasons for the effects observed.
KEYWORDS
Flotation, Saline water, Chalcopyrite, Pyrite