萤光滴定法测定镍的含量及其应用

CONTENT OF FLUORESCENCE DETERMINATION NICKEL AND ITS APPLICATION

采用萤光滴定法测定镍的含量，在ｐＨ＝１２．３８的碱性试液中加入过量的ＥＤＴＡ，用标准钙溶液反滴定过量的ＥＤＴＡ，以钙黄绿素作指示剂，三乙醇胺作掩蔽剂。测定时相对标准偏差小于５％，取样量可少至５μｇ，直接用于合金钢中镍含量的测定。

 method is described for the determination of nickel by fluorescence. An excess of EDTA is added to the nickel solution, alkalinity of the solution is adjusted to pH=12.38, and the excess of EDTA is back-titrated with calcium salt solution using calcein as indicator. In an interference study the masking agent triethanolamine was found to improve the end-point detection. Microgram amounts of nickel are determined with a relative standard errorless than 0.5%.The lower limit of determination is 5μg of nickel.The method has been successfully used for the nickel determination in steels.