The determination of sodium in high purity water with sodium-responsive glass electrodes

Abstract

A detailed investigation has been made of the accuracy of sodium-responsive glass electrodes for determining sodium (1 to 50 µg per litre) in high purity waters (e.g., condensed steam and boiler feed-water) from power stations. The electrode potential can be made to follow the Nernst equation down to a sodium concentration of about 1 µg per litre by controlling the pH of the sample and by using a continuous flow of the sample past the electrode. Octadecylamine seriously affected the response of the electrodes, but other impurities likely to be present in power-station waters caused no significant effects. The standard deviation of analytical results varied from 0·4 to 1·2 µg per litre at concentrations of 2 and 26 µg of sodium per litre. Details of a recommended analytical procedure for discrete samples are given.