The analysis of electrolytic capacitor electrolyte: the determination of chloride and sulphate in the p.p.m. range

Abstract

A method is described for the determination of chloride and sulphate ions in ethylene glycol-ammonium borate based electrolytes from electrolytic capacitors. The electrolyte is extracted with 80 per cent. ethanol. The chloride concentration is determined by titration with electrogenerated silver ions by differential electrolytic potentiometry, and the sulphate concentration by titration with barium in the presence of Thorin with a photoelectric titrator. Concentrations of 0·3 p.p.m. of chloride and 0·5 p.p.m. of sulphate in the final solution have been satisfactorily determined. Both procedures have applications in a wide range of analyses.