无汞开管法快速测定工业废水中的COD  

Rapid determination of COD in industrial wastewater by mercury-free open-tube method

作　　者：韦利杭[1] 楼振纲[1] 

机构地区：[1]浙江省环境监测中心站,浙江杭州310012

出　　处：《中国环境监测》2002年第1期18-21,共4页Environmental Monitoring in China

摘　　要：采用无汞开管法测定 COD。方法使用硫酸 -磷酸介质、重铬酸钾氧化体系 ,以硫酸银作催化剂 ,其他试剂包括硝酸银和硫酸铬钾以排除氯离子的干扰。样品在玻璃试管中进行消化 ,用一台恒温器加热样品 ,反应温度 1 65℃ ,加热时间只需 1 0 min,消解后剩余的重铬酸盐用分光光度法或滴定法测定。试验结果表明 ,本法的检出限为 1 0 .9mg/ L,测定范围为 3 0～ 1 5 0 0 mg/ L。由于方法不使用剧毒的汞盐 ,也就避免了汞对环境的污染。应用本法测定了大批量工业废水样品 。A reliable, simple and safe system to determine COD rapidly by a mercury free and open tube method was established The method employs K 2Cr 2O 7 as oxidant in a medium of H 2SO 4 H 3PO 4, with catalysis by Ag 2SO 4 and with addition of AgNO 3 and CrK(SO 4) 2·12H 2O to mask chloride Samples were digested in glass tubes and heated at 165℃ for 10min in an attemperator The residual dichromate was then determined by spectrophotometry or titration The results of the tests show that the detection limit for COD was 10 9 mg/L and in the range of 30(1500mg/L of COD the detected result was satisfied The advantage of this method avoids the use of toxic mercuride that could pollute the environment The developed method has been successfully applied to determine COD in large quantities of industrial wastewater samples

关 键 词：COD 无汞开管法 快速测定 工业废水 

分 类 号：X832[环境科学与工程—环境工程]