Microtitrimetry by controlled current potentiometric titration

摘要

The classical methods of titration require large volumes of chemicals. Microtritimetry is the method of choice since it utilizes small quantities of chemicals and yields less waste compared to other conventional methods. Thus it benefits both the analytical chemists and the environment. In this communication, microtitrimetry is performed by employing the technique of differential electrolytic potentiometry for the location of the end point. Oxidation-reduction titration using platinum electrodes is described. For the first time the endpoint for a sample of 1.0 μL of 0.10 M Fe(II) has been located by titration using a solution of Ce(IV). The optimum conditions such as volume of cerium ammonium sulfate added, current applied to polarize the electrodes in case of dc controlled current potentiometric titration (CCPT). The effect of changing the percentage bias of the square wave used to polarize the electrodes on the differential peak in case of ac CCPT has been investigated. The precision of this microtitrimetric method is also reported.