Tungsten determination in waters with preconcentration by sorption method

Optimal conditions of tungsten extraction from aqueous solutions containing 0.1-0.5 mol/l sodium chloride by a fibrous sorbent on the basis of polyacrylonitrile, modified by polyethylene polyamine, are found. It is established that 95-98% of tungsten is extracted by a sorbent from a 0.5 mol/l sodium chloride solution at pH 4 ± 0.5. The tungsten distribution coefficient of 500 ml/g, sorbent capacity for tungsten is more than 2 mmol/g. It is found that total tungsten desorption occurs, when 15 ml of 0.1 mol/l sodium hydroxide solution passes through the column at 5 ml/min rate. A method of determination of tungsten from 1 l sample at the 1-2μg/l level in waters with a high sodium chloride content is proposed