Separation of fine mineral particles by selective magnetic coating

This study deals with the separation of fine mineral particles using selective magnetic coating methods. The minerals used were quartz and magnesite, and the coating magnetic material was magnetite of heavy media grade ground to extremely fine particle size. The total interaction energies between each mineral and magnetite were calculated in the absence and the presence of dodecylamine as surfactant. Without surfactant, no magnetic coating was obtained on either of the single minerals, despite the favorable predictions. The magnetic coating results obtained on single quartz particles in the presence of surfactant were in full agreement with the predicted behavior based on the calculated energy barriers, while for magnesite the results were in partial agreement. The selective separation of quartz from magnesite was sufficiently confirmed when artificial mixtures of minerals were used. (C) 2002 Elsevier Science (USA).