Determination of titanium(IV) using o-hydroxyhydroquinonephthalein and Tween 20.

A new, simple and sensitive spectrophotometric method for the determination of titanium(IV) was studied using o-hydroxyhydroquinonephthalein(Qn.Ph.) and Tween 20. The analytical species of interest have an absorption maximum at 595 nm and obeyed Beer’s law over the range 0.3–2.4 μg of titanium(IV) in final 10 ml solution. This method was highly sensitive in comparison with Sandell sensitivity of 0.00025 μ/cm2 for titanium(IV) at an absorbance of 0.001 at 595 nm against water and the molecular extinction coefficient of the Qn.Ph.–titanium (IV) complex was 1.91×105 l mol−1 cm−1.