铁（Ⅲ）－邻硝基苯基荧光酮－CEHEAELA－Brij－35显色反应的研究与应用

Study on Colour Reaction of Iron with O-Nitrophenylfluorone -New Amphoteric-Nonionic Mixed Surfactants

本文研究了在新两性表面活性剂Ｎ－［Ｎ＇－（羧乙基）－Ｎ＇－（２－羟乙基）氨乙基］月桂酰胺钠盐（ＣＥＨＥＡＥＬＡ）和十二醇聚氧乙烯２３醚（Ｂｒｉｊ－３５）存在下，铁（Ⅲ）与邻硝基苯基荧光酮（Ｏ－ＮＰＦ）的显色反应．在ｐＨ６．０～９．０的ＨＡｃ－ＮａＡｃ缓冲介质中，Ｆｅ（Ⅲ）与Ｏ－ＮＰＦ形成１：３的桔红色配合物，最大吸收波长在５８０ｎｍ处，表观摩尔吸光系数ε＿（５８０）达１．４０×１０￣５Ｌ·ｍｏｌ￣（－１）·ｃｍ￣（－１），铁（Ⅲ）浓度在０～０．４８ｕｇ／ｍＬ范围内符合比尔定律．方法用于水样、人发及铝合金中痕量铁的测定，结果满意．

In the presence of new amphoteric surfactant N-[N-(carboxyethyl)-N'-(2-hydroxyethyl)aminoethyl] laurylamide(CEHEAELA)and Brij-35,the colour reac-tion of iron(Ⅲ)with O-nitrophenylfluorone(O-NPF)lias been studied.The orange com-plex with molar ratio of Fe:O-NPF to be 1: 3 in the HAc-NaAc buffer medium withpH6.0～9. 0 and in the presence of CEHEAELA-Brij-35,has the apparent molar ab-sorptivity of 1.4× 10￣5 L. mol￣(-1). cm￣(-1) at 580nm. Beer's law is obeyed for iron(Ⅲ)to befrom 0 to 0. 48μg .mL￣(-1).The method has been applied to the direct determination oftrace iron(Ⅲ)in the natural water,tap water,hair and aluminium alloys with satisfactory results.