Nickel(II)-selective electrodes based on macrocyclic compounds

Abstract

Poly(vinyl chloride)-based membrane electrodes based on synthetic macrocyclic compounds have been constructed by using sodium tetraphenylborate as an anion excluder, and dibutyl phthalate and dioctyl phthalate as plasticizing solvent mediators. These electrodes have a working concentration range of 10^–5–10^–1 mol l^–1 with a Nernstian slope of 29 mV per decade and are selective over a large number of bivalent and trivalent cations. Among monovalent cations NH⁺₄(0.5) and K⁺(0.6) interfere and their concentration, which can be tolerated over the whole concentration range, has been determined. The determination of the nickel concentration from the wastes of electroplating has been successfully achieved with these membrane sensors.