阳离子交换树脂富集衍生气相色谱法测定二甲基胂酸

PRECONCENTRATION AND DETERMINATION OF DIMETHYLARSONIC ACID BY DERIVATIVE GASCHROMATOGRAPHY AND CATION-EXCHANGE RESIN

实验发现,碘化二甲基胂(IDA)具有很好的色谱挥发性,在5％,10％SE-30柱上可得到较好的色谱峰。二甲基胂酸(DMA)碘化后生成碘化二甲基胂(IDA)。本文提出了新的碘化萃取体系:SnCl_2-KI(1moI/l)-HCl(6mol/l)-甲苯。该体系具有转化率高、干扰少的优点。实验还发现,经过阳离子交换树脂富集,有效地消除了低浓度时,DMA转化中或转化后的分解或吸附对测定的影响,从而提高了分析结果的准确度。

Dimethylarsonic acid (DMA) can be transformed into iododi-methylarsine (IDA) which is volatile and separated in the chro-matographic column with 5%, 10% SE-30 liquid phase. A new derivative extraction system is proposed, SnCl2-KI (1 mol/1)-HC1 (6mol/l)-toluene, which has the advantage of high percentage transformation and less interference. It is found that DMA being enriched,the effects of decomposition and adsorption in the low concentration of DMA is avoided efficaciously, and the accuracy and the reliability are raised.