铜的催化褪色动力学-负吸光度法测定

Determination of Copper by Catalytic Discoloring Kinetics-Negative Absorption Photometry

以催化褪色动力学光度法测铜为例 ,对负吸光度法用于褪色法能提高准确度与灵敏度、扩展线性范围、减小共存离子干扰及操作简便规范等的原因进行了系统的研究 ;实例表明 ,间接摩尔吸光系数为1.71×107L·moL -1·cm -1,可测浓度范围为40～3600ng·L -1及相对标准偏差为0.8%(n=9) ,均明显优于用经典吸光度法测定 ,且催化温度降低 ,反应时间缩短并省去反应抑制剂 。

With determination of copper(Ⅱ) by catalytic discoloring kinetic photometry as an example, the causes that can increase accuracy and sensitivity, extend the linear dynamic range, decrease the foreign ionic interference and lead to simplicity and norm of operation and so on have been studied in application of negative absorption photometry to discoloring photometry. In the example of determining copper(Ⅱ), the indirect molar absorptivity is 1.71×107 L·mol-1·cm-1,the linear range is 40～3 600 ng·L-1 and relative standard deviation is 0.8%(n=9), the results are obviously superior to the positive absorption photometry, and the method has the advantages of lower catalytic temperature, shortened reaction time, eliminating reaction inhibitor and easier operation.