Correlation of surface chemical heterogeneity at the micron scale with hydrophobicity and particle-bubble interaction forces

Froth flotation is the most widely used separation process where the valuable minerals are separated from the waste material based on the differences in surface hydrophobicity.

Coarse particle flotation is of special interest because it enables reducing energy consumption and early rejection of gangue while achieving a higher efficiency of coarse particles. However, coarse mineral particles are less liberated and, therefore, are more complex and have chemical heterogeneous surfaces. Hence, there is a need to better understand the impact of surface chemical heterogeneity at the micrometre scale on the flotation behaviour.

This project investigates the role that chemical heterogeneity plays on surface hydrophobicity and bubble-particle interaction forces. Surface chemistry information is obtained by Time-of-Flight Secondary Ion Mass Spectrometry analysis, surface hydrophobicity is ascertained by contact angle measurements and bubble-particle interaction forces measured by Atomic Force Microscopy.

Ore texture

This study will provide insights into the fundamental knowledge of bubble-particle interactions for complex surfaces which will be critical to understand the behaviour of coarse particles in flotation. This knowledge will, in turn, be translated into practical application of coarse particle flotation.

This project forms part of the ARC Centre of Excellence for Eco-efficient Beneficiation of Minerals.


This project is undertaken by the Sustainable Minerals Institute’s Julius Kruttschnitt Minerals Research Centre (JKMRC) Flotation Chemistry Group.