POTENTIOMETRIC MICRO-DETERMINATION OF SOME METAL-IONS USING CHLORANILATE PVC MATRIX MEMBRANE ELECTRODES

Chloranilate PVC matrix membrane electrodes have been developed. These are based on the use of aliquat-chloranilate ion pair in plasticized PVC matrices. The calibration slope is about 60 mV/decade. The limit o f detection is about 10(-5) M, the working pH range is 5-10, the elect rodes have been used in the determination of lead, mercury, and cadmiu m ions with chloranilic acid, separately and in binary mixtures. 2-Nit ro phenyl octyl ether, 2-nitro phenyl phenyl ether, dioctyl phthalate, dioctylsebacate, dioctyl phenyl phosphonate plasticizers are used; th ere were no significant differences in the performance characteristics of membranes for the various plasticizers. The life time of the elect rodes is greater than one month.