超声波提取土壤重金属形态试验的对比分析

Comparative analysis of ultrasonic extraction of soil heavy metal morphology

根据土壤形态的特性,加入不同提取液,采用超声波提取0.5 h与1.0 h作为土壤中重金属五步形态的前处理提取条件,与GB/T 25282―2010土壤和沉积物13个微量元素形态顺序提取程序中常规振荡16 h进行比对,根据对标准物质与土壤样品的测定证明Mn、Co、Cd、Cu、Ni、Pb和Zn在超声波前处理提取0.5 h时,部分数据准确度偏离规定值,提取率为66.0%~163%,误差较大。超声波前处理提取1.0 h与常规振荡16 h两种提取方法所得的结果基本吻合,提取率为95%~105%,所测数据符合标准值及准确度要求。用超声波提取重金属形态分析所需时间比常规振荡提取时间短,提取效率高。

According to the characteristics of soil speciation,different extracting solutions are added,and 0.5 h and 1.0 h ultrasonic extractions are used as five-step extraction conditions for heavy metal speciation in soil,compared with the application of standard GB 25282-2010,16-hour oscillation in the sequential extraction of soil and sediment micronutrients.According to the determination of reference materials and soil samples,this paper proves that the accuracy of some data deviates from the specified values when Mn,Co,Cd,Cu,Ni,Pb and Zn are extracted by ultrasonic pre-treatment for 0.5 h,with an extraction rate from 66.0%to 163%and an evident existence of errors.The results obtained by ultrasonic pre-processing for 1.0 h are in good agreement with those obtained by conventional oscillation for 16 h with extraction rates from 95%to 105%.The measured data satisfy the requirements of the standard values and rates of accuracy.To conclude,the efficiency of heavy metal extraction by ultrasonic wave is higher than conventional oscillating extraction.