国标法测定水中石油类方法优化

Optimization of national standard method for determination of petroleum in water

对HJ637–2018测定水中石油类含量的方法进行优化。分别对仪器选择、校准方式、萃取液过滤转移吸附、工作曲线法快速测定等进行了优化。用全自动萃取方式,仪器自动校准,采用长颈玻璃砂芯漏斗实现萃取液过滤、转移、吸附一体化,以工作曲线法定量。结果表明,水中石油类的质量浓度与吸收值呈良好的线性关系,相关系数为0.999957。测定结果的相对标准偏差为0.9%-5.8%(n=6),平均值与标准值的相对误差为–10%-–1.2%,加标样品的平均加标回收率为96.2%。优化后的方法简单、快速且准确,能有效降低人工劳动强度,提高萃取效率,适用于水中石油类的测定。

The determination method of petroleum in water by HJ 637–2018 was optimized. The instrument selection, calibration method, filtration and transfer adsorption of extracts, and fast determination by working curve method were optimized, respectively. The extraction liquid was filtered, transferred and adsorbed in an integrated way by using full automatic extraction method, automatic calibration of the instrument and long neck glass sand core funnel, and quantified by working curve method. The results showed that there was a good linear relationship between the mass concentration of petroleum in water and the absorption value, and the correlation coefficient was 0.999 957. The relative standard deviations of the results were 0.9%– 5.8%(n=6). The relative error between the average values and the standard values were –10%– –1.2%. The average recovery of the added standard samples was 96.2%. The method is simple, rapid and accurate. It can effectively reduce the labor intensity and improve the extraction efficiency. It is suitable for the determination of petroleum in water.