SPECTROMETRIC DETERMINATION OF TI(IV) WITH AN AZOPYRAZOLONIC DERIVATIVE

Spectrometric studies on the complexation of Ti(IV) with a new organic reagent obtained by coupling 3-methyl-1-phenyl-5-pyrazolone with diaz otized 3-amino-4-hydroxy-benzene-sulphonic acid were carried out. A 1: 2 Ti(IV):reagent complex, which is soluble in water, is formed at pH 5 -6.2. The maximum absorbance of the complex lies at lambda = 520nm, wh ere the absorbance of the reagent is very low. The molar absorptivity at this wavelength is 5x10(3) L mol-1 cm-1; the value of log K is 8.0 +/- 0.2. at 20 +/- 1-degrees-C and pH = 5.6. The Beer-Lambert law is f ollowed for titanium concentrations in the 0.2-10 mug Zr/mL range. Int erferences of Na(I), K(I), Ag(I), Mg(II), Ca(II), Zn(II), Cu(II), Fe(I I), Co(II), Ni(II), Al(III), Fe(III), Ce(III), Ce(IV), Zr(IV), ions we re investigated.