SPECTROPHOTOMETRIC DETERMINATION OF VANADIUM(III) AND VANADIUM(V) USING 2-{(E)-{3-{(E)-(2)HYDROXYPHENYL)METHYLENEAMINO} PHENYL}IMINOMETHYL}PHENOL
ABSTRACT
2-[(E)-[3-[(E)-(2-hydroxyphenyl)methyleneamino]phenyl]iminomethyl]phenol was synthesized from the condensation reaction of 1,3-diaminobenzene and 2-hydroxyzaldehyde in dimethylformaldehyde (DMF). Its coordination characteristic with vanadium(III) and vanadium(V) complexes was studied via, UV/Visible, IR and NMR spectroscopy; stoichiometric, melting point and conductivity determinations. The analytical data of these complexes and the mode of bonding show that, the ligand acted as a tetradentate ligand via coordination through the two azomethine nitrogen and the two hydroxylic oxygen. Mole ratio method indicated a 1:1 ligand to metal ratio for the complexes. Vanadium(III) and vanadium(V) were determined spectrophotometrically by measuring their absorbance at 400 and 405 nm respectively. From the calibration curve, Beer’s law was valid for vanadium(III) and vanadium(V) between 0.488 – 3.904 ppm. The calibration and analytical sensitivity of vanadium(III) complex is 0.074 and 0.32 while that of vanadium(V) is 0.024 and 24 respectively. Optimum pH for the formation of the complex was determined to be 10 and 11 for vanadium(III) and vanadium(V) respectively. Very few elements were found to interfere with the method. The method was successfully applied in the determination of vanadium in steel.