FIXATION OF ALIZARINE-S BY ZIRCONIA

For pH below the isoelectric point, the adsorption of alizarine S on z irconia may involve electrostatic attraction forces. For zirconia prep ared in molten salts media it occurs in two steps. The kinetic order o f both is one and they obey the Freundlich equation. They are attribue d to the fixation of alizarine S, respectively on the external surface of agglomerates and in the bulk of agglomerates, inside mesopores for med by the stacking of crystallites with a size large enough for the p enetration of the alizarine S molecule.