石蜡相分光光度法测定稀土的研究

Study on the determination of trace rare earths by paraffin phase spectrophotometry

系统研究了稀土 -8 羟基喹啉显色体系在石蜡相中的显色反应。在NH4Cl-NH3·H2 O(pH 9)介质中 ,稀土 -8 羟基喹啉显色络合物可定量被石蜡萃取 ,且固相色阶明显 ,RE2 O3 在 0～ 80 μg/ 5 0mL范围内符合比尔定律 ,从而建立了测量稀土的新的固相分光光度法。大多数干扰离子可通过控制溶液酸度进行萃取分离。方法应用于江西稀土矿中稀土总量的测定 ,结果满意。

RE-8 hydroxyquinoline color reaction in paraffin phase has been studied. In the medium of NH 4Cl-NH 3·H 2O(pH?9), the colored complex of RE-8 hydroxyquinoline can be quantitatively extracted with paraffin. Beer's law is obeyed in the range of 0 to 80μg/50mL for RE 2O 3. Most foreign ions can be separated from the system extracted by paraffin with controling the acidity of the solution. The method has been applied to the determination of trace rare earths in Jiangxi rare earth ores with satisfactory results.