摘要
由于硫酸往往含有微量硒杂质，本文改用硫酸钠作扶助剂提高高氯酸（硝酸）常压湿消化的允许消化温度，实现煤和环境及生物样品中有机砷和有机硒的全消化。建立了一个容易操作、重现性好的消化程序。用液氮低温捕集技术提高分析灵敏度。硝酸分解残留物对砷化氢和硒化氢生成过程的干扰，以及盐酸中微量氧化物对Ｓｅ（Ⅵ）还原处理的影响均用盐酸羟氨消除。ＥＤＴＡ可用于消除过渡金属离子对硒化氢生物过程的干扰。测定了多种标准参考物中微量砷和硒，得到与检定值相符合的结果。
An improved perchloric acid digestion procedure has been established for the routine determinations of arsenic and selenium in environmental and biological matrices and coal by hydride generation/atomic absorption spectrometry(HG/AAS)in conjunction with cryogenic trap precollection.Samples are digested with the mixture of nitric acid,perchloric acid,and sodium sulfate in conical glass flasks.NH2OH·HCl is used to reduce the interfering oxidants,i.e.,Cl2 that interferes with the reduction of Se(Ⅵ)to Se(Ⅳ),and NOx which interferes with the generation of both arsine and selenium hydride.The interference on the formation of selenium hydride from transition metal ions has been eliminated by addition of EDTA in the sample solutions.This procedure has been evaluated by analyzing several certified reference materials for both arsenic and selenium,and the results are in good agreement with the certified values.
出处
《中国环境监测》
CAS
CSSCI
CSCD
北大核心
1998年第1期16-20,共5页
Environmental Monitoring in China
关键词
砷
硒
高氯酸消化
煤
环境
生物样品
Arsenic,Selenium,Acid digestion,Coal,Environmental and biological materials,Hydride generation,AAS
