Selecting Collecting Agents for Flotation
S. A. Kondrat'ev
Chinakal Institute of Mining, Siberian Branch, Russian Academy of Sciences, Novosibirsk, 630091 Russia
Keywords: Flotation, collecting agent, physisorption, surface activity, induction time, wetting angle
Abstract
The characteristics of mineral floatability, namely, the wetting angle and the induction time, are examined. The agreement between the predicted floatability using these characteristics and the theoretical and experimental data is accessed. It is found that hydrophobicity defined by the wetting angle is not always a quantitative characteristic of floatation. The floatability predicted using the time of induction and mechanism of physisorption of collecting agents agrees with the tests and actual practice. The successive change in floatability of sulfhydryl and oxyhydryl collectors in transition between different reagents disagrees with the estimate of the collector force determined from the binding energy between the functional group of a collector and the cation of mineral surface. The force estimated as the effect of a physisorbed collector on the water interlayer between bubble and particle adequately describes floatability of minerals. The mechanism of physisorption of a collector is universal relative to different reagents, is applicable to the description of particle-bubble interaction and enables selecting the structure and composition of radical on an effective collecting agent.
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