一种快速测定化学需氧量(COD)的方法

提出用混酸来代替单一酸测定废水中的化学需氧量(COD)含量的方法。采用混酸(硫酸∶磷酸=4∶1)、重铬酸钾反应体系,氧化反应时间由标准方法的2h缩短为15min,是原来的1/8。用两种方法分别测试了标准物质所配制的废水和实际废水,经t检验和相关性分析,两种测试方法间不存在显著性差异,相关系数为0.95,相关性良好,同时实验得出本方法的检测限为5.15mg/L。本方法由于具有反应时间短,节省药剂和电费等优点,具有一定的可行性。

A Method to Rapid Measure Chemical Oxygen Demand

Mixed acid instead of single acid was proposed to measure chemical oxygen demand (COD) content. The mixed acid consisted of sulphuric and phosphorus acid with scale of 4:1 and oxidation reaction time shortening to 15 minutes. These two methods were used to measure wastewater prepared by standard substance and practical liquid water. Results showed that there existed no notable difference between the two methods and the correlation coefficient was about 0.95 that indicated a perfect correlation with detection limit of 5.15mg/L. The method is feasible and practical due to its shorter reaction time and cost effectiveness.