铝(Ⅲ)-3,5,7,2',4'-五羟基黄烯酮-吐温80体系的分光光度研究及应用

Study on the Colour Reaction of Aluminium (Ⅲ) with 3,5,7,2' ,4'- Pentahydroxyflavone in the Presence of Tween 80 and Its Application

本文研究了铝(Ⅲ)与 3,5,7,2＇,4＇-五羟基黄烯酮(桑色素,Morin)在非离子宏面活性剂Tween 80存在下,pH3.4—4.4的HAC-NaAc介质中,Al(Ⅲ)与Morin形成稳定的黄绿色配合物,其最大吸收波长在423nm处,表观摩尔吸光系数为7.2×10~·mol^1·cm^1 ,配合物组成比用Al(Ⅲ):Morin=1:3,其表观不稳定常数为1.43×10^(17),Al(Ⅲ)浓度在0～15μg/25ml之间符合比尔定律.以硫脲、抗坏血酸和邻菲罗啉作掩蔽剂,测定了电镀废水中微量铝,结果满意.

A simple sensitive and selective method for the spectrophometric determination of aluminium has been developed. Aluminium reacts with 3,5,7,2' ,4'- Pentahydroxyflavone (Morin) in the presence of Tween 80 to form a stable complex with Morin in HAc-NaAc solution at pH 4. 0. Its apparent molar absorptivity is 7. 2× 104L mol-1·cm-1 at 423nm. Beer's law is obeyed in the range of 0-15μg/25mL for aluminium. The color of aqueous solution is stable for at least 24 h. Thiourea, ascorbic acid and 1, 10-phenanthroline are used to increase the selectivity of the method. The proposed method has been used for the determination of trace aluminium in electroplating Waste-water with satisfactory results. The recovery of Al is in the range of 98. 3%-101.3%.