摘要
应用氢化物发生无色散原子荧光法测定水中痕量As(Ⅲ)和As(Ⅴ).在pH5.6—6.0时,As(Ⅲ)与KBH_4作用生成气态氢化物(AsH_3),被原子荧光仪测定.在此酸度下,AS(Ⅴ)不发生反应.在2NHCl溶液中,用硫脲和抗坏血酸还原As(Ⅴ)为As(Ⅲ),同法测总砷,用差减法求得As(Ⅴ).方法检出限0.1ppb,相对标准偏差4.6—5.8％,回收率93—104％.
Trace As(Ⅲ)and As(Ⅴ)was determined by hydride generation non-dispersive atomic fluorescence spectrometry(AFS)in water.An aliquot portion of the sample,adjusted to an acidity of pH5.6-6.0,is treated with KBH4,only As(Ⅲ)forms a gaseous hydride(AsH3).The AsH3 was determined directly by AFS.As(Ⅴ)was not formed AsH3 under the same condition.Another aliquot portion of the sample,reduced As(Ⅴ)with thiourea and ascorbic acid into As(Ⅲ)in 2N HCl,then the total contents of As was determined by the same method.The content of As(Y)is obtained by their difference.The detection limit of this method was 0.1 ppb.Relative standard deviation was 4.6-5.8%,and the recovery was 93-104%.ndition.Another aliquot portion of the sample,reduced As(Ⅴ)with thiourea and ascorbic acid into As(Ⅲ)in 2N HCl,then the total contents of As was determined by the same method.The content of As(Y)is obtained by their difference.The detection limit of this method was 0.1 ppb.Relative standard deviation was 4.6-5.8%,and the recovery
出处
《环境化学》
CAS
CSCD
北大核心
1990年第1期54-58,共5页
Environmental Chemistry
