FLOTATION SPECTROPHOTOMETRIC DETERMINATION OF PRASEODYMIUM WITH 5,7-DICHLOROQUINOLIN-8-OL AND RHODAMINE 6G

Praseodymium was determined by reaction with 5,7-dichloroquinolin-8-ol and Rhodamine 6G in a weakly alkaline medium. The flotation of the io n association complex was carried out with hexane, followed by dissolu tion in acetone for subsequent spectrophotometric determination. The m olar absorptivity was 1.83 x 10(5) 1 mol - 1 cm - 1 at 530 nm. Beer's law was obeyed in the range 8-240 mug l - 1 praseodymium. Praseodymium in aluminium metal and aluminium salts was determined by the proposed method in conjunction with an ion-exchange separation using Dowex 50W -X8 cation-exchange resin.