MAGNETIC NANOCOMPOSITES FLOCCULATING PROPERTIES IN WATER-SALT MEDIA

Magnetic flocculants based on Fe3O4 magnetite nanoparticles and ionogenic polyacrylamide flocculants have been synthesized. The magnetite colloidal chemical characteristics are determined - diameter d = 50,8 nm and electrokinetic potential ζ = -40,6 mV. The magnetic nanocomposites concentration and flocculating properties effect on the blue clay suspension sedimentation process was analyzed in the mode of free (unconstrained) sedimentation in flocculating effect and flocculating activity terms. The concentration range in which magnetic nanocomposites additives of various nature operate with the flocculant function has been determined. Clay particles sedimentation is associated with the magnetic flocculants macromolecules participation in the bridging bonds formation, which is confirmed by the parameter characterizing the magnetic flocculants macromolecules and clay particles number ratio. The ionic force effect the upon a change in the magnetic flocculants concentration on the blue clay suspension sedimentation is analyzed. It has been established that the mode of magnetic flocculants administration in an aqueous-salt medium and the non-identical properties of the formed floccules are associated with differences in the clay particles double electric layers structure. With increasing electrolyte (NaCl) concentration, the magnetic flocculant changes conformational state specificity: the transition from the unfolded conformation of the macromolecular tangle to a more folded globular structure, which means that the particular macromolecule participation probability a in the bridging bond formation decreases. The presence of intermolecular interactions between magnetic flocculants positively and negatively charged fragments compositions is noted. The flocculation process revealed patterns and effects in the mode of free (unconstrained) subsidence can be applied to the directional regulation of the suspensions stability involving magnetic nanocomposites.