不同消解对原子吸收光谱法测定三七中重金属铬的影响

以云南文山三七为材料,分析研究了用干法灰化、湿法消解前处理样品对原子吸收光谱法测定三七中重金属C r含量的影响,方法的相关系数为0.9993,干法灰化回收率为95.02%,湿法消解回收率为93.03%,分析结果满意。结果表明,干法灰化的最佳条件为灰化温度500—600℃、灰化时间6—8h。湿法消解的最佳消解体系为HNO3:HC lO4(V/V)=4:1体系。用干法灰化或常压下湿法消解处理样品,原子吸收光谱法可以准确测定三七中重金属C r含量,且方法简单、快捷。云南文山三七粉中重金属C r含量为1.8178μg/g。

Effects of Different Digestion Methods on Determination of Heavy Metal Cr in Panax pseudo-ginseng var.notoginseng by AAS

The content of heavy metal Cr in Panax pseudo-ginseng var.notoginseng from Wenshan,Yunnan Province was determined by atomic absorption spectrometry(AAS).The effects of the two pre-treatments,dry ashing method and wet digestion method,on the Cr content determination were studied.The correlation coefficient of the method was 0.9993.The recovery of dry ashing method was 95.02%,while the recovery of wet digestion method was 93.03%.The results suggested that the optimum condition for the dry ashing method was at 500—600℃ for 6—8h,and that for the wet digestion method was HNO3∶HClO4(V/V)=4∶1 digestion system.The content of Cr in Panax pseudo-ginseng var.notoginseng can be determined accurately by AAS via the pre-treatment of dry ashing method or wet digestion method at ambient pressure,and both methods are simple and rapid.The content of heavy metal Cr in Panax pseudo-ginseng var.notoginseng from Wenshan,Yunnan Province is 1.8178μg/g.