SYNTHETIC COPOLYMERS CONTAINING FREE OR PROTECTED CATECHOL RESIDUES FOR THE pH-CONTROLLED SELECTIVE FLOCCULATION OF ULTRAFINE DISPERSIONS OF ILMENITE WITH RESPECT TO RUTILE

ABSTRACT Several multifunctional polymers for the pH controlled flocculation of titanium minerals active towards ilmenite and selective respect to rutile have been prepared. They are radical vinyl copolymers containing catechol functions either free or protected and acrylic acid units. They show the distinctive property of changing their effect from flocculating to dispersing or inert and vice versa by changing pH, with great advantages for the best fulfilment of the flocculating process. The tendency of the ilmenite particles to gather, as a result of the combined effect of the cathecholic and carboxylic functions at acidic pH, is considered an essential conditions and a preliminary process for the formation of floes