Thallium Analysis Using Automated Photometric Titration

Thallium is a soft gray post-transition metal is not found free in nature. When isolated, it resembles tin, but discolors when exposed to air. Thallium can be titrated as Tl(III) in slightly acidic medium. To visualize the equivalence point, the indicator xylenol orange is used. The indication is done with the Optrode at a wavelength of 574 nm.