Natural metal sulfides as electrochemical sensors for redox titrations in γ-butyrolactone and propylene carbonate

Abstract

Natural monocrystalline pyrite, chalcopyrite, and galena have been used as indicator electrodes for potentiometric redox titrations in γ- butyrolactone and propylene carbonate. Copper(II) solution was employed as the titrating agent. The results obtained by using these electrodes were compared with those obtained by application of a platinum electrode under the same conditions, and good agreement, reproducibility, and accuracy were obtained. The results deviated by 0.16-0.50% from those obtained by using a platinum electrode. All the electrodes showed a relatively fast response time and can be used without any time limit or without considerable divergence in the potentials. The potential jumps at the titration endpoint obtained in the titration of some compounds by using a pyrite electrode are higher than those obtained by application of platinum as the indicator electrode. © Springer-Verlag 2010.