红外法测定废水中石油类和动植物油的质量控制手段

Quality Control on Determining Petroleum and Animal/Vegetable Oil in Wastewater byInfrared Spectrophotometry

目前,红外法测定废水中石油类和动植物油缺乏一套严密的质量控制手段。实验以红外分光光度法测定水中油类物质为方法依据(GB/T16488-1996),以废水为实验对象,以JK-951多功能红外测油仪、四氯化碳、无水硫酸钠、氯化钠、硅酸镁等为检测材料,采取全过程空白值的测定、空白质控图的绘制、方法检出限的测定、空白加标回收率的测定以及质控样的连续测定等一系列有机污染物质量控制措施手段,来完备红外法测油的实验室QA/QC措施。通过实验绘制了红外法油类测定空白质量控制图,测定并计算出方法检出限为0.07mg/L;测得空白加标回收率为76.7％～92.4％,质控样的测定结果完全符合质控标准值38.6±2.7的要求。同时,通过4种质控手段所得到的检测结果,验证了所用试剂及玻璃仪器的合格性、监测过程的准确性与精密性、在用仪器的受控性,从而通过控制样品分析过程中因玻璃器皿、试剂、萃取过程、仪器设备及人为误差所引起的数据的不可靠性,获取样品监测结果的可信性。

Determination of petroleum and animal/vegetable oil in wastewater by infrared spectrophotometry test is still lack of a series of quality control measures nowaday. Based on a lot of test data to constitute a series of quality control, as used blank test of full process, quality control chart of blank, MDL, recovery of blank spike and QC sample for determining organic pollutants by infrared spectrophotometry. The method depended on GB/T16488-1996, the apparatus and materials used were Model JK-951 multi-function infrared spectrophotometer and carbon tetrachloride, anhydrous sodium sulfate, sodium chloride, magnesium silicate, etc. The control chart for blank was generated through the experimentation. MDL was 0.07mg/L, recovery range of blank spike was 76.7% - 92.4%. The results of QC sample were in the range of the standard value. This paper conformed all of reagents and apparatus, veracity and precision, controlled the instruments by four QC methods. The detected results were real values with controlled all factors of analysis procedure.