SPECTROPHOTOMETRIC DETERMINATION OF MERCU RY(II) BY ITS ADSORPTION ONPOLYVINYL-CHLORIDE FILM AS ION ASSOCIATE WITH RHODAMINE-B

Cationic dyes formed ion-association complexes with tribromo mercury(I I) in aqueous solution. The complexes formed were adsorbed on a polyvi nyl chloride sheet (soft type), and the colored species adsorbed were used for the measurement of mercury. mum concentrations of KBr, H2SO4 and Rhodamine B were 1X10(-2)M (M = mol dm(-3)), 0.3 M and 1 X 10(-4) M, respectively. The detection limit of Hg was 0.04 ppm at shaking tim e of 10 min. and 35 degrees C. The proposed method is similar to ion p air solvent extraction but is simple and is more desirable than solven t extraction because it does not need any organic solvents.