A NEW MEMBRANE SENSOR FOR UO22-HYDROXYACETOPHENONEOXIME-THIOUREA-TRIOXANE RESIN( IONS BASED ON 2)

Poly(vinylchloride) (PVC) and polystyrene based uranyl ion-selective e lectrodes have been constructed using 2-hydroxyacetophenoneoxine-thiou rea-trioxane resin as electroactive material. For PVC based membranes dibutylphthalate (DBP) and dioctylphthalate (DOP) were used as plastic izing solvent mediators. These membrane electrodes work in the concent ration range of ca. 10(-5)-10(-1) M with a response time as fast as 30 s. The useful working pH range is 2.5-3.5 and the electrodes perform satisfactorily up to 20 %(v./v.) partially nonaqueous content. The ele ctrodes were used over a period of 4 months with good reproducibility (standard deviation = 0.5 mV). Further, the selectivity coefficient va lues of the order 0.1 for mono- and bivalent ions indicate moderate se lectivity for UO22+ ions over the interfering ions.