Study of iron and titanium complexes with propylenediaminetetraacetic acid by differential pulse polarography : Determination of iron and titanium in Portland cements

Differential pulse polarography is used to study the iron(III) and titanium(IV) complexes with propylenediaminetetraacetic acid (PDTA). The complexes produce reduction peaks at –0.09 V and –0.32 V (vs. Ag/AgCl/3 M KCl), respectively, at pH 4.5. This is used for a simultaneous, precise determination of iron and titanium. The detection limits in aqueous solutions were 5.0 × 10^?7 M for iron and 3.0 × 10^?7 M for titanium and linear calibrations were obtained in the range 4.0 × 10^?4–6.0 × 10^?4 M in both cases. Correct results were obtained for iron trioxide (ca. 2%) and titanium dioxide (ca. 0.3%) in Portland cements, with relative standard deviations of about 3% and 6%, respectively.