EXTRACTION OF ZIRCONIUM AS ZR(IV)-3-HYDROXYFLAVONE COMPLEX INTO BENZENE AND ITS DETERMINATION

An extractive spectrophotometric method is developed for the determination of zirconium. The procedure is based on the formation of a coloured complex by the reaction of zirconium with 3-hydroxyflavone in perchloric acid medium. The metal complex can be quantitatively extracted into benzene at pH 2.5, whose absorbance is measured at 405 nm. The method obeys Beer's law in the range 0-1.0 mug ml-1 with Sandell's sensitivity of 1.53x10(-3) mug cm-2. Re(VII), U(VI), V(IV), Ce(IV), Se(IV), Al(III), Bi(III), Sb(III), Cr(III), Co(II), Ni(II), Cu(II), Zn(II), Cd(II), Hg(II), Fe(II), platinum metals, alkali metals and alkaline earths metals do not interfere. Interference due to V(V), Cr(VI) and Fe(III) is eliminated by using masking agents.