Polarographic determination of tungsten in water

A possibility has been studied of using alternating-current polarography for determining tungsten in sewage and natural water contaminated with industrial discharge. Tungsten has been extracted with a solution of α-benzoinoxime in chloroform. 100-fold amounts of Cu, Zn, Co, Pb, and Fe do not interfere with determination. Linear relationship between the value of limiting current and tungsten concentration has been observed in solutions with concentration 10-6-5x10-5 g-ion/l. Reliability and reproducibility of the method have been tested with the use of industrial water from hydrometallurgical plant. A mean relative error is 5%