电感耦合等离子体质谱(ICP-MS)法同时测定荞麦秸秆中的8种重金属元素

基于硝酸-盐酸-氢氟酸消解体系,建立了马弗炉-微波消解-电感耦合离子体质谱(ICP-MS)法同时测定荞麦秸秆中的Cr、Cu、Ag、Mn、Fe、As、Ni、Pb等重金属含量测定方法。在微波消解的过程中,分别考察5种不同组合的混合酸体系及两种消解方法对荞麦秸秆中8种重金属测试结果的影响。实验结果表明,浓硝酸-浓盐酸-氢氟酸(6∶2∶2)混酸体系和马弗炉-微波消解样品前处理优于其他方法。在优化条件下,8种重金属加标回收率为91.2%~102%,相对标准偏差(RSD,n=5)为0.22%~4.7%,检出限为0.18~9.41μg/L。方法操作简便、快速、准确,结果可靠,能同时测定荞麦秸秆中8种重金属元素。

Simultaneous Determination of the 8 Heavy Metal Elements by ICP-MS

Based on the acid digestion system of nitric acid-hydrochloric acid-hydrofluoric,a muffle furnace-microwave digestion-inductively coupled plasma mass spectrometry method was established to simultaneously determine the content of heavy metals including Cr,Cu,Ag,Mn,Fe,As,Ni,Pb in buckwheat straw.In the process of microwave digestion,the effects of five different combinations of mixed acid systems and three digestion methods were investigated.The experimental results show that concentrated nitric acid-concentrated hydrochloric acid-hydrofluoric acid(6∶2∶2)mixed acid system and muffle furnace-microwave digestion are better than other methods.Under the optimized conditions,the recoveries of the eight heavy metals were 91.2%—102%,the relative standard deviation(RSD,n=5)was 0.22%—4.7%,and the detection limit was 0.18—9.41μg/L.The method is simple,fast,accurate and reliable.It can simultaneously determine eight kinds of heavy metals in buckwheat straw.