Ding Yaobin, Zhu Lihua, Yan Jingchun, Xiang Qingqing, Tang Heqing
College of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P.R. China.
J Environ Monit. 2011 Nov;13(11):3057-63. doi: 10.1039/c1em10454c. Epub 2011 Sep 14.
Persulfate can efficiently decolorize azo dyes through oxidizing these compounds, which enabled us to develop a method of rapid spectrophotometric determination of persulfate for monitoring the wastewater treatment on the basis of the oxidation decolorization of azo dyes. Four azo dyes with different molecular structures were investigated as probes, and the influences of operation parameters including reaction time, solution pH, initial dye concentration, and initial concentration of activator Fe(2+) were checked on the determination of persulfate. Under optimum conditions, the decolorization degree of the dyes responded linearly with persulfate concentration for all the four azo dyes, and the linear range and detection limit were found to be 2.0-150 μmol L(-1) and 0.62 μmol L(-1) for rhodamine B, 2.0-100 μmol L(-1) and 0.42 μmol L(-1) for methylene blue, 4.0-150 μmol L(-1) and 0.50 μmol L(-1) for methyl violet, and 20-150 μmol L(-1) and 8.1 μmol L(-1) for orange II. A persulfate treatment of a spiked wastewater sample was satisfactorily monitored with the new method.
过硫酸盐可通过氧化偶氮染料使其有效脱色，这使我们能够基于偶氮染料的氧化脱色开发一种快速分光光度法测定过硫酸盐的方法，用于监测废水处理情况。研究了四种不同分子结构的偶氮染料作为探针，并考察了反应时间、溶液pH值、初始染料浓度和活化剂Fe(2+)初始浓度等操作参数对过硫酸盐测定的影响。在最佳条件下，对于所有四种偶氮染料，染料的脱色程度与过硫酸盐浓度呈线性关系，罗丹明B的线性范围和检测限分别为2.0 - 150 μmol L(-1)和0.62 μmol L(-1)，亚甲基蓝为2.0 - 100 μmol L(-1)和0.42 μmol L(-1)，甲基紫为4.0 - 150 μmol L(-1)和0.50 μmol L(-1)，橙黄II为20 - 150 μmol L(-1)和8.1 μmol L(-1)。用该新方法对加标废水样品的过硫酸盐处理情况进行了令人满意的监测。
