不加热消解的 COD 快速测定方法及应用

摘要

针对国标中 COD 测定方法需要加热消解两小时的不简便性和量程上限仅仅到700 mg/L 的受限制性，设计了一种不加热消解的 COD 快速测定法。利用浓硫酸代替加热消解，即在样品中加入浓硫酸回流至室温便可达到加热消解两小时的效果，并采用了6次多项式的计算方法，使得实验结果更加准确。实验表明，本方法可以在保证精度的情况下将测量量程扩大至1000 mg/L，适用于更多化工领域的化学需氧量测定。%In national standards, the determination of COD needs to digest the sample under high temperature for two hours, and determination concentration range is within only 700 mg/L. Here, a rapid determination method without the heating digestion was designed. Adding sulphuric acid into the sample to reflow to room temperature achieved the result of 2 h heating digestion. The experimental results show that the determination range can be expanded to 1 000 mg/L.