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Minerals & Metallurgical Processing

, Volume 21, Issue 1, pp 33–35 | Cite as

Influence of nanoscale roughness on surface wettability

  • S. C. Brown
  • B. M. Moudgil
Technical Paper

Abstract

A number of studies have suggested that microscale asperities enhance bubble-particle attachment efficiency. However, in practice the roughening of particulate surfaces can also lead to a decrease in flotation. In the present investigation it is proposed that nanoscale asperities may be partially responsible for this phenomenon. It is suggested that as inter-asperity separation distances are reduced capillary effects are enhanced, leading to the formation of stable liquid domains that adversely impact bubble-particle adhesion. In addition, obstruction of surfactant self-assembly may occur, further limiting flotation.

Key words

Wettability Flotation Bubble-particle attachment 

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Copyright information

© The Society for Mining, Metallurgy & Exploration 2003

Authors and Affiliations

  • S. C. Brown
    • 1
  • B. M. Moudgil
    • 1
  1. 1.Department of Materials Science and Engineering and Engineering Research Center for Particle Science and TechnologyUniversity of FloridaGainesvilleUSA

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