荧光法和紫外法测定海水中石油类的对比研究

Comparative Study on the Determination of Petroleum in Seawater by Fluorescence and Ultraviolet Methods

本文采用标准GB 17378.4-2007中荧光分光光度法和紫外分光光度法测定海水中石油类,分别对两种方法的标准曲线绘制、方法检出限、精密度及准确度等关键指标进行对比研究。结果显示:荧光法的标准曲线相关系数r为0.9996、0.9998、0.9999,紫外法的标准曲线相关系数r为0.9996、0.9999、0.9997,均大于0.999;荧光法的方法检出限为0.0004 mg/L,明显低于紫外法的检出限0.0030 mg/L;荧光法的空白水样加标、海水及其海水加标的精密度为0.20%~2.74%,优于紫外法的精密度0.13%~4.09%;荧光法的样品加标回收率为95.1%~102.1%,优于紫外法(87.0%~96.1%)。综上所述:两种方法的标准曲线、方法检出限、精密度和准确度均满足标准检验要求,可用于测定海水中石油类,但荧光法的灵敏度更高,实验数据更稳定,更适合测定石油类浓度较低的海水样品。

In this paper,the fluorescence spectrophotometric method and the ultraviolet spectrophotometric method of standard GB 17378.4-2007 were used for the determination of petroleum products in seawater,and the key indexes of the two methods,such as standard curve,method detection limit,precision and accuracy,were compared and studied respectively.The results showed that the correlation coefficients of the standard curves of the fluorescence method were 0.9996,0.9998,0.9999,and the correlation coefficients of the standard curves of the UV method were 0.9996,0.9999,and 0.9997,which were all greater than 0.999.The limit of detection of the fluorescence method was 0.0004 mg/L,which was significantly lower than that of the UV method was 0.0030 mg/L.The precision of the fluorescence method for the spiking of blank water samples,seawater and its seawater spiking was 0.20%~2.74%,which was better than that of the UV method with the precision of 0.13%~4.09%;the recoveries of the spiking of the samples of the fluorescence method were 95.1%~102.1%,which was better than that of the UV method was 87.0%~96.1%.In conclusion,the standard curves,method detection limits,precision and accuracy of the two methods meet the requirements of standard test and can be used for the determination of petroleums in seawater,but the fluorescence method is more sensitive,the experimental data are more stable,and it is more suitable for the determination of seawater samples with lower concentrations of petroleums.