Dispersion of praseodymium-doped zirconium silicate pigment in aqueous suspension by modified hydroxyl copolymer

Water-based copolymer dispersants, i.e., sodium polyacrylic acid-co-2-acrylamide-2-methylpropanesulfonic acid-co-glycerol monomethacrylate (PASGs), were synthesized for dispersion of praseodymium-doped zirconium silicate pigment in aqueous suspension with polyacrylic acid-co-2-acrylamido-2-methylpropanesulfonic acid (PAS). Effects of different parameters on the dispersion behavior of colloidal particles were investigated via sedimentation tests. The samples were characterized by particle size analysis, Fourier transform infrared spectroscopy, and electrokinetic potential measurement. The interparticle potential energy at different pH values and dispersant types was calculated. The results show that PASG(1) at 3 wt.% addition effectively disperses the colloidal particles in the denser suspension of 35 wt.% at pH 7.0, compared to PAS. Dispersant PASG(1) provides greater steric hindrance and electrostatic repulsive energies than dispersant PAS. The dispersion/aggregation behavior of colloidal particles in the suspension under different conditions was also predicted by a modified population balance model (PBM). The predicted data are similar to the experimental results. (C) 2019 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.