Analysis of Difference between Zinc Salt and Aluminum Salt Treated Titanium Dioxide

Using metatitanic acid from titanium white production by sulphate process as the raw material,the aluminum salt and zinc salt were used as salt treatment agents to treat the metatitanic acid,and initial product of titanium white was obtained after calcination.The difference of viscosity and zeta potential for the two kinds of titanium dioxide slurries was compared and analyzed,and the morphology and structure of the samples were characterized by SEM and XRD respectively.The results show that under the same concentration,pH and amount of dispersant,the slurry containing aluminum salt treated sample has a lower viscosity and better dispersibility.Zeta potential analysis shows that the aluminum salt treated sample has a higher absolute zeta potential than that of the zinc salt treated sample.XRD analysis shows that aluminum ions are doped into the lattice and replace part of the titanium ions in the aluminum salt treated titanium dioxide after calcination,leading to a change in its unit cell parameters and an increase in the cell volume.Meanwhile,the aluminum salt treated titanium dioxide has a more electronegative character due to the substitution of tetravalent titanium ions by trivalent aluminum ions,resulting in a better dispersibility.