Voltammetric determination of 2-, 3- and 4-chloroaniline in mixtures

The oxidative-voltammetric behaviour of 2-, 3- and 4-chloroaniline has been investigated at the glassy carbon electrode over the pH range 1–12. The optimum pH values for the linear-sweep and differential-pulse voltammetric determination of these compounds were found to be 1.95 for 2- and 3-chloroaniline and 8.1 for 4-chloroaniline. Differentiation of the three compounds in a mixture was achieved by using a combination of high-performance liquid chromatography with voltammetric detection. This method could be used to determine concentrations of 2- and 4-chloroaniline down to 2 ng and 3-chloroaniline down to 1 ng for a 20-µl injection on to the chromatographic column.