段雪梅 颜晔 戴晓军 曾俊源 张燕波 巢文军

摘 要：采用微波（硝酸+双氧水）、微波（硝酸+氢氟酸）、微波（硝酸+氢氟酸+高氯酸）及电热板和全自动石墨消解仪等消解方法测定土壤标样重金属Cu、Zn、Ni、Cr、Pb、Cd的含量，研究不同测定方法对重金属测定结果的影响。结果表明：除铜之外，微波（硝酸+雙氧水）消解其他元素测定结果均超出了标样保证值的允许范围，相对误差在-39.9%～9.20%。微波（硝酸+氢氟酸）消解铜和铬的测定结果相对误差为-2.4%、-6.9%;锌和镍的测定结果均偏低，相对误差分别为-15.6%、-12.0%;铅和镉则偏高，相对误差分别为18.1%、19.5%。微波（硝酸+氢氟酸+高氯酸）除元素铅和镉的结果偏高外，相对误差分别为18.1%、19.5%，其余元素的测定结果均在标样保证值的允许范围内，相对误差在-10.2%～2.9%。电热板消解测定所有测定元素均在标准样品的推荐值范围内;全自动石墨消对Cu、Cr、Pb有较好的效果;而Zn的个别样品测定结果明显偏低、Ni明显偏高。微波（不同试剂组合）消解体系对不同元素的消解效果明显不同，因此，实际工作应用中要有针对性地加以选择来应用。石墨消解能将土壤样品Cu、Cr、Pb元素消解完全，精密度和回收率达到测试的要求，且安全性高、污染少、操作简单、智能化，适合大批量样品的同时处理。

关键词：消解方法;土壤;重金属

中图分类号 S181.3文献标识码 A文章编号 1007-7731（2021）09-0098-04

Abstract： This paper analyzed the effects of microwave digestion（HNO3+H2O2）， microwave digestion（HNO3+HF） and microwave digestion（HNO3+HF+HClO4）， electric heating plate and automaticgraphite digestion instrument on the determination results of heavy metals elements Cu， Zn， Ni， Cr， Pb and Cd in standard soil samples. The results indicated all the heavy metal are not within theguarantee value of the standard sample， except for copper with microwave digestion（HNO3+H2O2）and the relative error ranged from -39.9% to 9.20%. The relative error of the determination results are -2.4% and -6.9%， respectively for Cu and Cr and -15.6% and -12.0%， respectively for Zn and Ni and 18.1% and 19.5%， respectively for Pb and Cd with microwave digestion（HNO3+HF）.The results of Cu， Zn， Ni， Cr， are all within theguarantee value of the standard sample， except for Pb and Cd and the relative error are 18.1% and 19.5% respectively with microwave digestion（HNO3+HF+HClO4）.The measurement results of the electric heating plate are all within the recommended value range of the standard sample and automaticgraphite digestion hasgood effect on Cu， Cr and Pb， while the determination results of individual samples of Zn are obviously lower and obviously higher for Ni.The microwave （different reagent combination） digestion system has significantly different digestion effects for different elements. Therefore， it is necessary to make target selection in daily analysis.graphite digestion could digest soil samples completely for Cu、Cr、Pb. The precision and recovery rate could meet the test need and had the advantages of high safety， low pollution， simple operation and realization of intelligence， it was suitable for processing of large quantities of samples simultaneously.

Key word： Digestion method; Soil; Heavy metal

土壤重金属污染是当今世界不容忽视的环境问题，由于重金属在土壤中移动性差、滞留时间长、不易被生物降解，而且容易通过食物链传递进入生物体而危害生物安全和人类健康[1]。……