A STOPPED-FLOW KINETIC PROCEDURE FOR SIMULTANEOUS DETERMINATION OF IRON, ANTIMONY AND VANADIUM

A kinetic procedure for simultaneous determination of iron, antimony a nd vanadium is proposed based on their inductive effect on the chromiu m (VI)- iodide reaction in weak acidic medium. The reaction was monito red with stopped-flow spectrophotometric technique by using iodine-sta rch complex as indicator. Calibration graphs are linear for 0 approxim ately 1.6 mug/ml Fe(II), 0 approximately 2.0 mug/ml Sb(III) and 0 appr oximately 2.8 mug/ml V(IV), respectively, and detection limits are 0.0 12 mug/ml Fe, 0.014 mug/ml Sb and 0.010 mug/ml V. 100 to 1000 times hi gher concentrations of CO2+, Ni2+, Mn2+, Cu2+, Cd2+, and Zn2+ do not i nterfere with the determination. The method is applied for determinati on of iron, antimony, vanadium in wastewater and a synthetic sample; t he results are satisfactory.