浊点萃取分光光度法测定水样中的痕量汞

Determination of trace mercury in water samples by spectrophotometry after cloud point extraction

目的：建立以双硫腙为络合剂、Triton X-100为表面活性剂的浊点萃取-可见分光光度法测定痕量汞的新方法。方法：Hg^2＋与双硫腙络合物在Triton X-100溶液中经水浴、离心、冷却后被分离、富集在表面活性剂中，富集相用水稀释后，在λmax=500nm处测定其吸光度。结果：在最佳实验条件下，吸光度与汞的浓度在0．01～0．4μg／ml范围内呈良好线性关系，工作曲线回归方程为A=2．2035c＋0．022，相关系数r=0．9988。结论：本法不仅灵敏、准确、选择性好，而且不使用有毒有害的有机溶剂，实现了绿色分析。

Objective：To develop a new method for the determination of trace mercury in water by spectrophotometry after cloud point extraction. Methods：Mercury was separated and preconcentrated owing to the formation of a complex with dithizone in the presence of Triton X - 100. After phase separation, the surfactant -rich phase was diluted with distilled water, and then determined by Spectrophotometer at λmax = 500 rim. Results ： Under optimum conditions, analytical graph was rectilinear in the concentration range of 0. 01 - 0. 4 μg/ml. The regression equation was A = 2. 2035c ＋ 0. 022, correlation coefficient r = 0. 9988. Conclusion：Without using toxic and harmful organic solvents, the proposed method is sensitive, accurate and selective.