土壤中二噁英类测定的前处理技术分析

Analysis of Pretreatment Technology for the Determination of Dioxin in Soil

为了探究土壤中二噁英类测定的关键前处理技术,确保土壤测定结果能真实反映二噁英类污染水平,选取一批次土壤样品,通过对样品前处理过程是否进行盐酸发泡处理、索氏提取和ASE提取两种不同的样品提取方式、不同的多层复合硅胶柱净化次数、不同的活性碳柱净化次数等进行比较。研究结果表明盐酸发泡处理后的结果更接近土壤实际值。第一步净化操作中C1、C2、C3、C4样品的毒性当量浓度分别是8.4、1.8、2.1、1.6 ngTEQ/kg,说明在遇到复杂基体样品时,需要进行两次硅胶柱净化处理,才能达到更好的去除干扰物的目的。第二步活性碳柱净化步骤中,使用一次净化即可达到较为满意的结果。研究结果为土壤中二噁英类测定的关键前处理过程提供了数据支持,为深入打好土壤中持久性有机污染防治攻坚提供了技术支撑。

In order to explore the key pretreatment techniques for the determination of dioxins in soil,and ensure that the results can truly reflect the level of dioxin pollution.In this paper,the different pre-treatment process including whether hydrochloric acid foaming treatment,soxhlet extraction and ASE extraction,different purification times of multilayer silica gel column and activated carbon column were compared.The study result showed that the results of hydrochloric acid foaming treatment was closer to the actual value of soil.The toxic equivalent quantity of C1,C2,C3 and C4 were 8.4,1.8,2.1 and 1.6 ngTEQ/kg,respectively,in the first stage of purification,indicating that when encountering complex matrix samples,two times of Silica Gel column purification treatment were needed to achieve the purpose of better removal of interfering substances.In the second step of active carbon column purification,a satisfactory results can be achieved by using only one purification.The results of this study can provide data support for the key pre-treatment processes for the determination of dioxins in soil and can provide technical support for the prevention and control of persistent organic pollution in soil.