摘要
消解酸度、滴定酸度、还原性离子、消解时间等是影响重铬酸钾滴定法测定水中化学需氧量(COD)的重要因素。本文对这些影响因素开展研究,结果表明,消解酸度从50%(v/v)减少至30%,COD的测定值降低了35%~57%。氯离子的氧化产物为氯气,但采取0.025 mol/L的重铬酸盐时不能被完全氧化;铵离子单独存在时对测定COD值无贡献,但与氯离子共存时有贡献;碘离子则无此现象。
In this paper,the performance of digestion acidity,titratable acidity,reducing ion and digestion time were investigated on the determination of chemical oxygen demand(COD)in water by potassium dichromate titration.The results show that the value of COD was reduced by 35%~57% as the acidity of digestion dropted from 50%(v/v)to 30%.Chloride can be oxidized to Chlorine gas,but not be completely oxidized by dichromate with the concentration of 0.025 mol/L.The reducing ion ammonium did not contribute to the determination of COD,but contributed with the coexistence of chloride ions.In addition,iodide did not have the phenomenon.
作者
赵新亭
黄河仙
高茜瑶
谢沙
潘海婷
朱建辉
邓露
朱日龙
ZHAO Xin-ting;HUANG He-xian;GAO Xi-yao;XIE Sha;PAN Hai-ting;ZHU Jian-hui;DENG Lu;ZHU Ri-long(Ecological Environment Monitoring Station of Xinjiang Uygur Autonomous Region,Urumqi Xinjiang 830011,China;Chemistry and Chemical Engineering,Hunan University,Changsha Hunan 410082,China;Hunan Ecological Environment Monitoring Center,Changsha Hunan 410082,China;Ningxia Hui Autonomous Region Eco-environmental Monitoring Center,Yinchuan Ningxia 750001,China;Hunan Provincial Center for Ecological and Environmental Affairs,Changsha Hunan 410019,China;Turpan Ecological Environment Monitoring Station,Xinjiang Uygur Autonomous Region,Turpan Xinjiang 838000,China)
出处
《干旱环境监测》
2023年第3期102-106,共5页
Arid Environmental Monitoring
基金
湖湘高层次人才聚集工程(2021RC5030)
湖南省2021年创新型省份建设专项郴州国家可持续发展议程创新示范区项目重大项目(2021sfq26)。
关键词
重铬酸钾滴定法
化学需氧量(COD)
消解酸度
氯离子
铵离子
potassium dichromate titration
chemical oxygen demand(COD)
digestion acidity
chloride ion
ammonium ion
