改进的甲酚红褪色光度法测定微量二氧化氯

DETERMINATION OF TRACE CHLORINE DIOXIDE BY IMPROVED SPECTROPHOTOMETRIC METHOD WTTH CRESOL RED DECOLOURATION

对甲酚红褪色光度法测定微量二氧化氯进行改进，在ｐＨ＝３．０缓冲介质中，加入适量氨磺酸铵（０．０７４ｍｏｌ／Ｌ）作为掩蔽剂，可在Ｃｌ２（〈８５ｍｇ／Ｌ），ＣｌＯ（〈１２．４ｍｇ／Ｌ），ＣｌＯ２（〈２０ｍｇ／Ｌ）共存时选择性测定ＣｌＯ２线性范围０～３ｍｇ／Ｌ，检测限０．００３ｍｇ／Ｌ，方法回收率９７．２％～１０６．０％，该方法简便，快速，准确，适用于水溶液中微量ＣｌＯ２的测定。

The spectrophotometric method with cresol red decoboration to determine the Content of trace chlorine dioxide(CIO2) in water was improved.In the buffer medium at pH=3.0,the concentration of CIO2 could be detected selectively in the existence of foreign substances such as Cl2(<85mg/L),ClO-(<12.4mg/L),ClO2(<20mg/L)with Ammnium Sulphamate as masking reagent.The linear range of determination was 0~3mg/L,the detection limit was 0.003mg/L and the recovery was 97.2%~106.0%.The method was simple,convenient,rapid,accurate and was successfully applied to the determination of trace amount of ClO2 in the water solution.