Abstract

Flotation Spectrophotometric Determination Of Platinum With Isochromatic Ion-Pair Between Tetrabromofluorescein And Rhodamine 6G

Author(s): Baosheng Liu, Zhichao Liu, Zhaozhen Cao, Jing Gao

The flotation spectrophotometric method for determination of platinum (Pt) with isochromatic dye ion-pair was described. [(2R6G) (PtBr6)⋅3(R6G⋅Br)] was resolved and Rhodamine 6G (R6G) was entered into aqueous phase when pH = 5.5 HAc-NaAc buffer solution was added to the [(2R6G) (PtBr6)⋅3(R6G⋅Br)] in medium of toluene. And then R6G·TBF was flotated by tetrabromofluorescein (TBF) with toluene. The floatation was dissolved in acetone and absorbance of the solution was measured at 530 nm. The sensitivity was increased because of the assistant effect between dyes (Pt: R6G: TBF=1: 5: 5). The molar absorptivity of this method was 9.94×105 l·mol-1·cm-1. The concentration of Pt obeyed Beer’s law in the range of 0 ~ 0.5 mg l-1 with a relative standard deviation 4.4 ~ 5.8 %; the recovery of the measurement was 96.0 ~ 102.0 %.The method has been applied to the determination of platinum in platinum contained catalysts with good results.