Abstract:

A new method for detecting water sample COD rapidly-using ultrasonic assisted digestion(UASD) of water samples under normal temperature and pressure,combined with detection methods,such as spectrophotometry(SP) or oxidation-reduction potential(ORP) for detecting water sample COD,has been brought forward. The experimental results show that the optimal time for UASD method to digest water samples is around 4 min. By means of drawing the work curve with standardized potassium acid phthalate solution,UASD-SP method is used for detecting the COD in water samples(diluted COD< 500 mg/L). Compared with international detected value,the accuracy of this detected value is -5.4%--2.1% and the precision of the experiment is 0.42%-2.8%. The feasibility of applying ultrasonic assisted digestion method for detecting COD rapidly is verified.

Key words: chemical oxygen demand(COD), ultrasonic assisted digestion, oxidation-reduction potential, spectrophotometry

摘要：

提出快速检测水样化学需氧量(COD)的新方法,即在常温常压下利用超声消解(UASD)水样,并结合分光光度法(SP)或氧化还原电位法(ORP)检测水样COD。实验表明,UASD法消解水样的最佳时间在4 min左右;用标准邻苯二甲酸氢钾溶液绘制工作曲线,采用UASD-SP法对污水样品的COD(经稀释COD < 500 mg/L)进行检测,测得的COD值与国标法测定值对比,准确度在-5.4%~-2.1%,实验精密度在0.42%~2.8%。实验证明了应用超声消解快速检测COD方法的可行性。

关键词: COD, 超声辅助消解, 氧化还原电位法, 分光光度法

CLC Number: 

• X132