离子交换色层法分离和富集水中微量有机胂

SEPARATION AND PRECONCENTRATION OF TRACE ORGAN ARSENIC SPECIES IN WATER SAMPLES BY ION EXCHANGE CHROMATOGRAPHY

摘要: 研究了用阳离子交换色层法分离和富集水中甲基胂酸（ＭＭＡ）和二甲基胂酸（ＤＭＡ）的实验条件。对样品的吸附酸度、淋洗液的组成及淋洗速度进行了选择。在吸附酸度ｐＨ＝２条件下，用６０ｍＬ０．５ｍｏｌ／ＬＣＨ３ＣＯＯＨ－ＣＨ３ＣＯＯＮＨ４（ｐＨ＝４．７）洗脱ＭＭＡ，继续用６０ｍＬ３ｍｏｌ／ＬＮＨ３·Ｈ２Ｏ洗脱ＤＭＡ，淋洗速度控制在０．１～０．１５ｍＬ／ｍｉｎ，洗脱液用中子活化法进行测定。实际水样的加标回收率：ＭＭＡ为（９６±２）％，ＤＭＡ为（１０３±３）％，它们的相对标准偏差分别为６％和３％。

Abstract: A simple and sensitive method for the separation and determination of monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA)is presented. The separation is achieved by cation exchange chromatography. MMA and DMA are determined by neutron activation analysis of the fractions collected. The recoveries of MMA and DMA are (96±2)% and (103±3)%, their relative standard deviations are 6% and 3%,respectively.