新型酸性光亮镀锡铜合金液中微量铜的快速测定

Rapid Determination of Minim Copper in Newly Acidic Bright Tin-Copper Alloy Plating Bath

采用 5 -Br -PADAP光度法测定酸性光亮镀锡铜合金液中的微量铜 ,优选出最佳测定波长。研究了酸度 甘油浓度和显色剂浓度以及各种干扰离子对测定的影响 ,铜含量在 0～ 2 0 μg/ 2 5mL范围内 ,服从比尔定律。加标回收试验结果表明 ,该方法重复性好 ,准确度高 ,简单快速 ,回收率为 99%～ 10 2 % ,具有很好的实用价值和应用前景 。

Minim copper in new acidic bright tin-copper alloy plating bath was determined by spectrophotometrie method using 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol(5-Br-PADAP)as chromogenic reagent,and measuring wavelength was optimized.The effects of acidity,concentration of glycerol and chromogenic reagent,and various interference ions were studied.Beer's law was followed for copper content among 0-20μg/25 mL.Experimental results of standard addition show that the method has good repeatability and accuracy with recovery rate of 99%～102%.The method is simple,rapid and has better practicability and application prospect that is acceptable for direct determination of minim copper without separation in acidic bright tin-copper alloy plating bath.