Kaoma, J & Yarar, B


Thermodynamic Condition for "Gamma" Flotation, by J. Kaoma and B. Yarar, Zambia Journal of Science and Technology, Vol.8, no.1, September 1989, Pg.47-56.


Using the definition of the critical surface tension of wetting solids (tc) and the Gibbs' adsorption isotherm, coupled with Young-Dupre's equation, the equilibrium thermodynamic condition for "Gamma" flotation has been derived. It is defined by the relation, Cos Qe = tc/tlg At equilibrium for "Gamma" flotation to occur, the liquid/gas interfacial tension (tlg) should be larger than the critical surface tension of wetting of the solid surface, meaning that the equilibrium contact angle (Qe) should be greater than zero, or cos Qe < 1, a pre-requisite for the solid/gas bubble attachment.

This definition holds for any solid surface in the absence of any specific adsorption at the solid/liquid and solid/gas interfaces. Contact angle and flotation data are presented to sustain this definition.

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