间接分光光度法对水中二氧化氯的测定

Determination of chlorine dioxide in water by indirect spectrophotometry

目的建立一种分析较高浓度二氧化氯溶液的便捷分析方法。方法基于二氧化氯自身的颜色和氧化性,分别建立了直接分光光度法和罗丹明B、亚甲基蓝和丽丝胺绿B间接分光光度法。结果罗丹明B、丽丝胺绿B和亚甲基蓝的最大吸收波长分别为554、618和664nm,测定范围分别是51.5~560mg/L、22~224mg/L和86.8~2688mg/L;在pH值为2~9范围内pH值对丽丝胺绿B影响甚微,但亚甲基蓝受pH值变化的影响较大,ClO2^-和ClO3^在500mg/L内对测定无干扰。结论丽丝胺绿B间接分光光度法是一种稳定的二氧化氯分析方法,罗丹明B可以用中性及碱性样品的测定,亚甲基蓝适用于分析测定更高浓度二氧化氯消毒剂,但需注意样品pH值与标准样品一致。

Objective To establish a convenient analytical method for measuring high concentration of chlorine dioxide solution. Methods Rhodamine B,methylene blue,and lissamine green B indirect spectrophotometry were established based on the color and oxidizing properties of chlorine dioxide itself. Results The maximum absorption wavelengths of rhodamine B,lissamine green B and methylene blue were 554,618,and 664 nm,respectively,and the linear ranges of which were 23-560 mg/L,11-224 mg/L,67-2 688 mg/L. Lisamine green B was almost unaffected by pH in the range of pH 2-9,while methylene blue was greatly affected. Cl O-2 and Cl O-3 did not interfere with the assay under 500 mg/L. Conclusion Lisamine Green B indirect spectrophotometry is a stable method for chlorine dioxide analysis. Rhodamine B can be used for the determination of neutral and alkaline samples. Methylene blue is suitable for the analysis of higher concentration chlorine dioxide disinfectants,but the pH of the sample should be consistent with the standards.