基于Fenton试剂和微型光谱仪实现水质COD和总磷的在线测定

基于Fenton试剂和微型光谱仪，实现了水质化学需氧量(chemical oxygen demand，COD)和总磷(total phosphorus, TP)的在线测定。该系统结合超声辅助，基于Fenton试剂实现了常温常压下水中有机化合物和有机磷化合物的在线消解。系统基于微型光谱仪实现了可见光光谱探测并采用多波长分光光度法分析光谱数据。结果表明，系统具有测定时间短，低功耗，结构简单和二次污染少的优点。同时，系统测定相对误差小于10%，COD和总磷检测限分别为2和0.008 mg·L-1，灵敏度分别为0.021 3和0.452 6，标准偏差分别为5.6%(15.0 mg·L-1 COD标样)和5.8%(0.010 mg·L-1 总磷标样)。实际水样测定结果与国家标准分析方法比较无显著差异。

On-Line Determination of Chemical Oxygen Demand andTotal Phosphorus in Water by Using FentonReagents via a Micro-Spectrometer

This paper presents a system for on-line determination of chemical oxygen demand (COD) and total phosphorus (TP) in water by using Fenton reagents via a micro-spectrometer.The system uses Fenton reagents with ultrasonic-assisted to realize on-line digestion of organic compounds and organic phosphorus compounds in water samples under normal temperature and normal pressure,and uses a micro-spectrometer to realize multi-wavelength spectrophotometric detection.The results show that the system realize less measuring time,lower power consumption,simpler system structure and less secondary pollution.Moreover,the results show that the relative error is ≤10%,the limit of detection (LOD) are 2 mg·L-1 COD and 0.008 mg·L-1 TP,respectively,the sensitivities are 0.021 3 COD and 0.452 6 TP,respectively,and the precision is around 5.6% RSD at 15.0 mg·L-1 COD (n=7) and 5.8% RSD at 0.010 mg·L-1 TP (n=7).In addition,there are not significantly difference between the Chinese national standard analysis methods and the methods used in proposed system.