氨水络合分离-电感耦合等离子体质谱法测定高温合金中痕量银

详细研究了ICP MS测定银时93Nb1 6 O+ 和91 Zr1 6 O+ 对1 0 9Ag+ 和1 0 7Ag+ 干扰和消除干扰的方法 ,建立了氨水络合分离-ICP MS测定高温合金中痕量银的方法。在 pH9氨性介质中 ,银和氨络合保留在溶液中 ,锆和铌生成沉淀而被分离 ,消除了铌和锆的干扰。加Re或Rh内标校正仪器漂移和基体效应 ,以ICP MS测定。测定结果准确可靠 ,方法的测定范围为0.0 0 0 0 0 5 %～ 0 .0 1% ,检出限为 0.0 0 0 0 0 3 %。

Determination of trace silver in superalloys by ICP-MS after complexing separation with ammonia

In this paper,a method for the determination of trace silver in superalloys by ICP-MS was established.The interferences of ~(91)Zr~(16)O~+ and ~(93)Nb~(16)O~+ on silver and the separation of silver from niobium and zirconium were investigated in detail.By using appropriate settings of operational parameters the interferences were minimized.In the ammonia medium at pH9,silver ion reacts with ammonia to form a complex Ag(NH_3)_2]~+,zirconium and niobium are precipitated and separated,and the interferences from Zr and Nb can be completely eliminated. Rhenium or rhodium as internal standard was used for correcting the drift of instrument and the effect of matrix in the determination of trace silver by ICP-MS. The method has been applied to the determination of trace silver in superalloys with satisfactory results.The appropriate concentration range of Ag is 0.000005%-0.01% and the detection limit is 0.000003%.