Role of Water Structure-Making/Breaking Ions in the Cationic Flotation of Kaolinite: Implications for Iron Ore Processing

Abstract

Australia is the largest exporter of iron ore in the world. The high Al content in Australian hematite/goethite ores is detrimental to blast furnace and sinter plant operations. Of the Al containing minerals in iron ore, kaolinite is a common gangue mineral frequently found in iron ore deposits. In iron ore flotation pulp, various ions exist and may interfere with the flotation performance when their concentration is high enough. In this work, the role of a water structure-making ion, i.e. Na + , and a water structure-breaking ion, i.e. K + , in the flotation of kaolinite under reverse cationic flotation conditions, the most widely used flotation route of iron ore in the world, was studied in a series of laboratory batch flotation tests. It was found that K + , a water structure breaker, can better reduce the zeta potential of kaolinite and thus causes higher flotation recovery of the clay mineral, in comparison to Na + , a water structure maker. The different effects of the alkali metal cations on kaolinite flotation are attributed to the different aggregation degree of kaolinite particles in the presence of these cations.

On the use of Na₂SO₃ as a pyrite depressant in saline systems and the presence of kaolinite

“…In the case of the KCl solution, an IEP was generated at pH 6 and negative potentials at values higher than that pH. For these study conditions, the values obtained replicate those reported by Ma et al (2012) in their study of the role of the water structure in kaolinite (Ma et al, 2012). This is attributable to the difference in ions.…”

“…Clays in NaCl solutions tend to form aggregates with one another due to the presence of Na + ions. Ma et al (2012) determined that this type of ion reduces the zeta potential (see Fig. 3C), promoting the floatability of kaolinite.…”

Impact of seawater salts on the viscoelastic behavior of flocculated mineral suspensions

“…This is attributed to differences between ions, where some are structure makers and others structure breakers [1]. These changes have direct impact on rheological parameters of suspensions such as the viscosity or yield stress [2][3][4][5][6].…”

Raman micro-spectroscopy as a viable tool to monitor and estimate the ionic transport in epithelial cells

“…As a general rule, the most cations are structure makers, with the exception of some alkali metals. In fact, while sodium is slightly structure maker, potassium is slightly structure breaker 47 , 48 . Anions with high charge density are structure makers, while monovalent anions, like Cl − , are structure breakers, with the exceptions of fluoride and hydroxide.…”