PRECONCENTRATION AND VOLTAMMETRIC MEASUREMENT OF SILVER(I) WITH A CARBON-PASTE ELECTRODE MODIFIED WITH 2,9-DICHLORO-1,10-PHENANTHROLINE-SURFACTANT

A chemically modified carbon paste electrode was prepared by incorpora ting appropriate amounts of 2,9-dichloro-1,10-phenanthroline and surfa ctant directly in a paste mixture. The electrode was able to bind silv er ions chemically, and gave a better voltammetric response for silver than did ordinary carbon paste electrodes. The response was character ized with respect to paste composition, preconcentration time, silver ion concentration, reproducibility, possible interferences and other v ariables. The method showed good linearly for 8 x 10(-10)-5 x 10(-7) m ol l(-1) silver(I) in nitric acid medium. The performance of the elect rode was verified by the determination of silver(I) in waste water.