Polarographic investigation of the catalytical adsorptive complex behavior of trace iron

Department of Chemistry, Shandong University, Jinan, P.R. China

Manuscript received 23 December 1998, accepted 28 December 1998

In HAc-NaAc (1 : 1) buffer solution, Fe^III-5-Br-PADAP-NO₃ system sensitively presents a reductive wave at a banging mercury drop electrode (HMDE). The reductive wave is a catalytical adsorptive complex wave. In 0.05 mol dm^-3 HAc-NaAc and 4.0 x 10^-6 mol dm-³ 5-Br-PADAP solution, the second derivative peak height of the reductive wave is linearly proportional to the concentration of Fe^III in the range from 1.0 x 10^-10 to 1.0 x 10^-7 mol dm^-3. The detection limit is 6.0 x 10^-11 mol dm^-3. The method has been applied to determine trace amount of iron samples of pig meat and tap water.