RAPID, SELECTIVE, DIRECT AND DERIVATIVE SPECTROPHOTOMETRIC DETERMINATION OF TITANIUM WITH 2,4-DIHYDROXYBENZALDEHYDE ISONICOTINOYL HYDRAZONE

A simple and sensitive spectrophotometric method is developed for the determination of titanium in aqueous medium. The metal ion forms a red dish brown coloured complex with 2,4-dihydroxybenzaldehyde isonicotino yl hydrazone (2,4-DHBINH) in the pH range 1-7. The complex shows two a bsorption maxima, one at 430 nm and the other at 500 nm. The reagent s hows appreciable absorbance of 430 nm and negligible absorbance at 500 nm at pH 1.5. Beer's law is obeyed in the range 0.09 to 2.15 mu g ml( -1) of titanium(IV). The molar absorptivity and the Sandell's sensitiv ity of the method are 1.35 x 10(4) l mol(-1) cm(-1) and 0.0049 mu g cm (-2), respectively. A method for the determination of titanium by firs t-order derivative spectrophotometry is also proposed. The methods hav e been employed successfully for the determination of titanium in seve ral alloy and steel samples.