溶剂浮选吸光光度法测定微量铂

Determination of Trace Platinum by Solvent Sublation Spectrophotometry

本文应用溶剂浮选吸光光度原理,拟定了微量铂的分析方案。用CTMAB作捕收剂,捕收〔Pt(SnC1_3)5〕^(3-)离子,浮选至有机溶剂乙酸乙酯中,在398nm处用1cm的比色皿测定吸光度,可以测定ppb级的铂。富集比为40,表观摩尔吸光系数为2.6×10~5,铂的回收率接近100％。

A method for determination of trace Pt is reported. This mthod, solvent sublation spec-trophotometry, is based on the ion-associate formed by the anionic chlorostannite eomplex of platinum with cetyltrimethylammonium brocmide(CTMAB). The ion-associate finally formed is slight soluble in water, but it is readily soluble in CH_3COOC_2H_5. The optimum condition of sublation is tested by orthogonal test. The sbsorbance of the solution is measured at 398nm against a reagent blank prepared in the same way. The apparent molar absorptivity is 2.6×10~5 L. mol^(-1)·cm^(-1)·Beer＇s law is obeyed over the range of 0～120μg(the solution volume is 200ml, the organic phase volume is 5ml). The recovery of Pt is nearly 100%.