【摘要】 在氯乙酸介质中,在 Tween 80和溴化十六烷基三甲基铵（CTAB）参与下,Ti（IV）与溴邻苯三酚红（BPR）形成两种络合物,BPR过量时为红紫色络合物(λ_max=527nm);Ti（Ⅳ）过量时为兰色络合物(λ_max=650nm)。本文系统研究红紫色络合物的形成条件。试验表明,此类络合物具有极高的灵敏度(ε_527nm=2.5×10⁶I·mol^-1·cm^-1)但选挥性较差。反应的适宜酸度为pH2.40—2.91。络合物中Ti（Ⅳ）与BPR的摩尔比为2:5。钛含量在2—12ng/ml范围遵守比尔定律。研究了30多种离子的干扰。讨论了反应灵敏度提高的原因。更多还原

【Abstract】 A hypersensitive colour reaction of Ti(IV)-bromopyrogallol red (BPR)-tween 80-cetyltrimethylammonium bromide (CTAB) has been investigated spectrophotometrically. Ti(IV) forms a red-purple colour complex at pH 2.40-2.91 in monochloroacetic medium with apparent molar absorptivity of 2.5×106 1·mol-1·cm-1 at 527nm. The molar ratio of Ti(IV) to BPR is 2:5 Beer’s law is obeyed for Ti(IV) in the range of 2-12 ng/ml. The effects of diverse ions on the determination of Ti(IV) are examined. The reasons of enhancing sensitivity of the reaction are discussed.更多还原