一类新的4-取代胂酸型变色酸偶氮多卤显色剂的合成及其与稀土元素显色反应的研究

Syntheses of a Kind of New 4-Substitned Arsecazopolyhalogen Reagents and their Color Reactions with Rare Earths

本文研究了五个结构新颖的显色剂与稀土元素的显色反应。其中的二溴羧基偶氮氯肿(CAsA-DBK)与稀土元素反应具有对比度大、灵敏度高、选择性好等优点。在0.6mol/LHClO_4介质中,不加任何掩蔽剂条件下,只与铈组稀土显色,与钇组稀土几乎不显色,是一个较有特色的铈组稀土试剂。

The syntheses and the color reaction of five new colur reagents with rare earth elements are studied in this paper. Among them, the colour reaction of bibromo-caboxy-4-chloroarsenazo ( CAsA- DBE ) has the advantages of great contrast, high sensitivity and good selectivity. In a medium of 0. 6mol/L HClO_4 without any masking agent,it reacts only with cerium-subgroup rare carths, almost not with yttrium-subgroup elements. So it is a good color reagent for cerium-subgroup rare earths.