A study on the separation of magnesite fines by magnetic carrier methods

The separation of magnesite fines from serpentine fines by magnetic carrier methods has been examined in this study. The zeta-potential of serpentine, magnesite and magnetite was measured with and without dodecylamine as surfactant. The interaction energies between the particles were then calculated. Without the surfactant, no magnetic coating was obtained despite the favourable predictions for narrow pH ranges. When surfactant is added in suspensions of separate minerals, the serpentine particles obtain a magnetic coating strongly attached to the surface in the range 6<pH<11 while the magnesite particles obtained a weak and limited extension coating only for pH>9. The experimental results are in excellent agreement with the theoretically predicted results for serpentine and in fairly good agreement For magnesite. When artificial mixtures of serpentine and magnesite were used, the metallurgical results are slightly different from the results on separate minerals. (C) 1999 Elsevier Science B.V. All rights reserved.