The effects of calcium ions on the flotation of sillimanite using dodecylammonium chloride

Abstract

The effects of Ca2+ ions on the flotation of sillimanite using dodecylammonium chloride as a collector were investigated by micro-flotation tests, zeta potential measurements, solution chemistry analysis and molecular dynamics (MD) simulation. The micro-flotation results indicated that Ca2+ ions remarkably inhibit the flotation of sillimanite in the pH range of 2.0-9.0. The point of zero charge (PZC) of sillimanite changed from 5.4 to 6.1 with the addition of Ca2+ ions. Meanwhile, the calculated concentration of RNH3+ in the sillimanite interface layer decreased in the presence of Ca2+ ions. The results of MD simulation revealed that Ca2+ ions have strong binding energy with the sillimanite (010) surface, and the binding energy of RNH3+ with sillimanite (010) surface reduced in the presence of Ca2+ ions. The conclusions drawn from the computations are in good agreement with the experimental results.