光谱学与光谱分析, 2009, 29 (8): 2227, 网络出版: 2010-05-26
紫外-可见光谱法测定高锰酸盐指数的研究
Study on the Determination of Permanganate Index by UV-Vis Spectrometry
高锰酸盐指数 紫外-可见光谱法 地表水 水质监测 Permanganate index UV-Vis spectrometry method Surface water Water quality monitoring
摘要
高锰酸盐指数(CODMn)是反映饮用水水源受到有机污染的一项重要指标, 现行的国标测定法为滴定法。 本文探索研究了紫外可见光谱法测定地表水中高锰酸盐指数的新方法。 内容包括: 测定波长的选择、 H2SO4用量的影响、 KMnO4浓度和用量的影响、 加热温度和时间的影响、 方法的线性关系以及与滴定法的对比试验。 通过研究, 得到方法的优化测定条件: 测定波长为525 nm, 25% H2SO4的用量为5.00 mL, 0.012 50 mol·L-1 KMnO4标准使用液的用量为2.00 mL, 加热温度为100 ℃, 加热时间为30 min。 方法用于了嘉陵江、 长江水中高锰酸盐指数的实际分析, 获得了满意的结果。 研究结果表明与国标法相比, 本法具有快速、 易操作、 灵敏度高、 精密度好、 试样量少, 成本低、 易实现水质在线监测等特点, 是一种环境友好的监测分析新方法。
Abstract
Permanganate index is an important parameter to evaluate the organic pollution for water sources, and the current national standard method is titration analysis which needs large sample and is complicated. A new analytical method of measuring permanganate index in surface water using UV-Vis spectrometry has thus been studied. In the laboratory work, analytical wavelength of UV-Vis spectrometry was chosen. The effect of sulfuric acid dosage, concentration and dosage of KMnO4 together with heating temperature and time was identified. In order to evaluate this new method, the linear relationship of this method was tested and the analysis results were compared with those by titration method. The selected optimum analysis parameters were: 525 nm wavelength, 25% H2SO4 dosage of 5.00 mL, 0.012 50 mol·L-1 KMnO4 dosage of 2.00 mL, 30 min heating time at the temperature of 100 ℃. This UV-Vis spectrometry method was successfully applied to measuring the permanganate index of the samples collected from the Jialing River and the Yangtze River. Compared with the current national standard method, this method is time and cost efficient, sensitive and precise, with low reagent usage; and is also easy to be manipulated and can be employed for online monitor, thus making it an environmental friendly analysing method.
蒋绍阶, 石芙蓉, 郑怀礼. 紫外-可见光谱法测定高锰酸盐指数的研究[J]. 光谱学与光谱分析, 2009, 29(8): 2227. JIANG Shao-jie, SHI Fu-rong, ZHENG Huai-li. Study on the Determination of Permanganate Index by UV-Vis Spectrometry[J]. Spectroscopy and Spectral Analysis, 2009, 29(8): 2227.