流动注射停流法快速测定环境水样中COD

FIA DETERMINATION OF COD IN ENVIRONMENTAL WATER BY STOP-FLOW TECHNIQUE

应用流动注射停流分析技术 ,对环境水样中的COD进行测定。采用KMnO4 作氧化剂和光度分析指示剂 ,葡萄糖作基准物质 ,在反应温度为 95℃ ,停流 5min时 ,COD测定范围为 0～10 0mg·L- 1,检出限为 2mg·L- 1,相对标准偏差为 0 .8% (n =9) ,回收率为 85 %～ 95 %。Cl-<15 0mg·L-

A new FIA method for the rapid determination of chemical oxygen demand (COD) in environmental water samples by stop flow technique is described. Acidic potassium permanganate solution is used both as oxidant and photometric indicating reagent. Glucose is used as standard. When the time of stop flow used is 5min and the reaction temperature is carried out at 95℃, the detection limit and relative standard deviation found are 2mg·L -1 and 0.8%, respectively. The determination range is 2～100mg·L -1 COD. The recoveries are in the range of 85%～95%. Choride ion up to 150mg·L -1 level does not interfere without any masking agent. The time for a determination is about 5 minutes and 30 seconds.