Ramakrishna T V, Rahim S A, West T S
Chemistry Department, Imperial College, London S.W.7, U.K.
Talanta. 1969 Jul;16(7):847-53. doi: 10.1016/0039-9140(69)80125-6.
A simple and rapid method is described for the determination of niobium in steel with Bromopyrogallol Red. After dissolution of the sample, niobium is extracted along with iron from concentrated hydrochloric acid into isopentyl acetate. Niobium and iron are stripped into an aqueous solution containing sodium acetate, and EDTA, ammonium chloride, tartaric acid, and Bromopyrogallol Red are added to complex the niobium. The niobium-Bromopyro-gallol Red complex along with excess of reagent is extracted into isopentyl acetate containing di-n-octylmethylamine, and measured at 610 nm. The molar absorptivity is 2.50 x 10(4) and Beer's law is obeyed up to 27 mug of niobium. The method is free from interferences and can be applied to the analysis of samples containing as little as 0.01 % niobium.
介绍了一种用溴邻苯三酚红测定钢中铌的简单快速方法。样品溶解后，铌与铁一起从浓盐酸中被萃取到异戊基乙酸酯中。铌和铁被反萃取到含有醋酸钠的水溶液中，加入乙二胺四乙酸（EDTA）、氯化铵、酒石酸和溴邻苯三酚红以络合铌。铌-溴邻苯三酚红络合物与过量试剂一起被萃取到含有二正辛基甲胺的异戊基乙酸酯中，并在610nm处进行测定。摩尔吸光率为2.50×10⁴，在铌含量高达27μg时符合比尔定律。该方法不受干扰，可用于分析含铌量低至0.01%的样品。
