Abstract

Flocculation of fine paramagnetic particles rendered hydrophobic by absorption of surfactants in external magnetic field in aqueous suspension, called simultaneous hydrophobic and magnetic flocculation (SHMF), has been studied through a theoretical approach and experiments. All interactions between fine paramagnetic particles in the case of SHMF are being discussed in this paper. Through extension of the classical DLVO theory, the theory of stability of fine particles in aqueous suspension in the case of SHMF is proposed. Potential energies of interaction between fine rhodochrosite particles rendered hydrophobic by absorption of sodium oleate in external magnetic field have been calculated from the theory. Experimental results of SHMF of fine rhodochrosite and siderite particles showed that SHMF exhibits much stronger and faster aggregation then either hydrophobic or magnetic flocculation alone. Two examples of SHMF applied to fine particle processing are given.