Application of the catalytic properties of N-methylthiourea to the determination of In(III) at low levels by square wave voltammetry

摘要

This article proposes a simple and fast method of In(III) determination in the presence of Cd(II) and Pb(II). The catalytic activity of N-methylthiourea was used in the In(III) electroreduction, which also had a slight effect on the electroreduction process of Cd(II) and Pb(II). By applying square wave voltammetry it was possible to determine 3 x 10~(-7) mol dm~(-3) In(III) in the presence of 5 x 10~(-5) mol dm~(-3) Cd(II) and 1 x 10~(-4) mol dm~(-3) Pb(H) in 5 mol dm~(-3) NaClO4 at pH 2. The calibration curve for In (III) was linear from 3 x 10~(-7) to 5 x 10~(-4) mol dm~(-3). The relative standard deviation for In(III) determination was about 3.0%.