双最大吸收波长光度法测定天然水中的银

DETERMINATION OF SILVER IN NATURAL WATER BY DUAL-MAXIMUM-ABSORPTION WAVELENGTHES SPECTROPHOTOMETRY

在乙酸介质中,银(Ag^+)亚铁氰化钾—邻菲啰啉反应有催化作用,体系由红色渐变为蓝绿色。据此,本文依据稳定悬浮体系光学吸收性质、研究双最大吸收波长以测定银的新方法。该方法将红色褪色和绿色生色双定量联系起来,分析灵敏度比单波长法提高1倍,而且操作较简单,精密度较高,计算曲线稳定,适合于天然水和部分较洁净污水中Ag的分析。

In acetic acid solution silver (Ag^+)can accelerate the reaction of potassium ferrocyanide [K_4Fe(CN)_6] and 1,10-phenanthroline and the solution will change from red into blue color. In this paper with the optical absorption property of stable suspending particle the new method to determine silver called dual-maximum-absorption wavelengthes spectrophotometry is presented. It can realize dual-quatitative analysis to measure the fading and developing at the same time. Experimental results show that the sensitivity is 2 times higher than that with single wavelength method. And the operation is simple and the precision is high. Meanwihle, the silver calculated curve is very stable. The method is suitable to analyse natural water and so on.