Three phase interactions, mineral

Froth flotation is a complex three phase physico-chemical process which is used in mineral processing industry to separate selectively fine valuable minerals from gangue. The importance of the mineral froth flotation process to the economy of the whole industrial world is important. As costs has increased in mining industry and ore grades and metal prices decreased, role of mineral flotation has become even more important. The flotation process depends among many other factors on control of the pulp aeration, agitation intensity, residence time of bubbles in pulp, pulp density, bubble and particle size and interaction and pulp chemistry. 

The mechanistic significance of Eq. 3.1, despite its great utility in mineral solubility studies, is, on the other hand, almost nil. No implication of reaction pathways, other than the postulate of stoichiometric control of aqueous-phase products, can be made on the basis of an overall reaction alone, since it features only enough species to satisfy minimal equilibrium criteria. Any number of additional kinetic species can intervene to govern the reaction pathways, which may be parallel, sequential, or a combination of these two, and the detailed interactions of the solid phase with the aqueous phase are often unlikely to be represented accurately by a spontaneous decomposition reaction like Eq. 3.1. As a case in point, the dissolution reaction of calcite (the forward reaction in Eq. 3.14) may be considered. Given the existence of protons and carbonate species in the aqueous-solution phase, at least three overall reactions more specific than Eq. 3.14 can be postulated to epitomize the detailed interactions of calcite with aqueous species 7,33,34... 

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