Automated determination of uranium(VI) in seawater using on-line preconcentration by coprecipitation

Abstract

An automated method is developed for the spectrophotometric determination of nanoamounts of uranium(VI) with Arsenazo III using online preconcentration by the coprecipitation of the uranium complex of the reagent with organic coprecipitants. The collector was an Arsenazo III ion pair with organic cations poorly soluble in water. The concentrate was separated by filtration through a cellulose fiber membrane and dissolved in a flow of an organic solvent; the analytical signal was recorded as the output peak. The developed method is characterized by simplicity, sufficiently high sensitivity, high throughput and rapidity, and can be used for the selective determination of uranium(VI) in complex liquid matrices. The detection limit is ∼0.01 ng/mL (3s, n = 5, P = 0.95). The throughput of the method is 150 samples per hour.