Potentiometric Sensors for Pr(III) Based on N-N᾽o‐Phenylene‐bis(salicylideneimine) Using Epoxy Resin and PVC as Binding Materials

Abstract

Listen

Translate article

Praseodymium(III) ion selective electrodes have been prepared using N-N᾽o‐phenylene‐bis(salicylideneimine) as a suitable electro‐active material. Several membranes comprising of varying compositions of electro‐active material with epoxy resin and polyvinylchloride (PVC) as binding materials were prepared. However the one with composition 50% Schiff᾽s base and 50% binder was found to exhibit best performance. The sensor with epoxy resin as binder presents a linear dynamic range of 1.0×10-6 to 1.0×10-1 M with a Nernstian slope of 19.9 mV/decade. The sensor has a quick response time. (less than 10 s). The reproducibility of the electrode is about 6 months without any considerable, noticeable potential divergence. The sensor is effective in pH range of 3.00‐8.62. In case of PVC as binding material; the results are compared for same composition of electro‐active material. The sensor presents a linear dynamic range of 1.0×10-6 to 1.0×10-1 M with a slope of 14.0 mV/decade. The response time of the sensor is found to be 20s with a reproducibility of 4 months. The sensor is effective in pH range of 2.97‐8.90. Effect of internal solution was studied and both the electrodes could satisfactorily be used in partially non‐aqueous medium. Selectivity coefficients for both the electrodes have been determined by FIM (fixed interference method) with respect to many rare earth metal ions, alkali & alkaline earth metal ions and some transition metal ions. Both the electrodes were successfully employed as indicator electrode in the potentiometric titration of Pr(III) ions with oxalic acid and EDTA.