DE-INKING OF OIL AND WATER-BORNE PRINTING INKS - A NEW FLOTATION DE-INKING MODEL

Oil-borne printing inks are hydrophobic with a negative surface charge in the pulp suspension to be de-inked. In contrast, water-borne flexo inks are hydrophilic and negatively charged. Based on this different nature of printing inks, their different behavior in flotation de-inking is obvious. Current de-inking models do not describe the effects of, for example, nonionic surfactants or water-borne inks in flotation. The model presented is valid for different surfactant ionogenity and types of inks.