锌系与铝系盐处理钛白差异分析

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

以硫酸法钛白二洗偏钛酸为原料,分别采用铝盐和锌盐为盐处理剂对偏钛酸进行处理,经过煅烧后得到钛白初品。对比分析了两种钛白的浆料黏度和Zeta电位差异,然后通过XRD和SEM对样品微观形貌和结构进行表征。结果表明,在相同浓度、相同pH和相同分散剂加量条件下,铝盐处理的样品打浆后黏度更低,分散性更好。Zeta电位分析表明铝盐处理的样品比锌盐处理的样品的Zeta电位绝对值高;XRD分析表明铝盐处理的样品经过煅烧后铝离子代替部分钛离子掺杂进入到二氧化钛晶格中,导致其晶胞参数变化,晶胞体积变大,同时由于三价的铝离子代替四价钛离子导致其更偏负电性从而具有更好的分散性。

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.