浊点萃取-荧光光度法测定废水中痕量铝

The Determination of Trace Aluminum in the Wastewater by Cloud Point Extraction and Spectrofluorimetric Method

建立了荧光光度法测定水中痕量铝离子的浊点萃取分离富集新体系.在pH=5.6的HAc-NaAc缓冲体系中,水样中的铝与8-羟基喹啉生成疏水性络合物.通过95℃水浴加热1.5 h,8-羟基喹啉-铝络合物被萃取到乳化剂(OP)表面活性剂相并与水相分开.在激发波长365 nm和发射波长510 nm下进行荧光测定,测定铝的线性范围为10.00～250.00μg/L,方法的检出限(3σ)为0.39μg/L,相对标准偏差(RSD)为3.6%,该法用于各种水样中痕量铝的测定,加标回收率为96%～105%,结果令人满意.

A cloud point extraction（CPE） method for the separation and preconcentration of trace aluminum in water prior to its determination by spectrofluorimetry has been developed.In pH 5.6 HAc-NaAc buffer solution,Al（Ⅲ） reacted with 8-hydroxyquinoline to form a hydrophobic complex,which could be extracted into OP nonionic surfactant phase and separated from the aqueous phase after water-bath at 95 ℃ for 1.5 h.The spectroflurimetric detection was under the condictions of λex=365 nm and λem=510 nm.A good linearity was observed for aluminum in the range of 10.00-250.00 μg/L with the detection limit of 0.39 μg/L and the relative standard deviation of 3.6%（n=11）.The developed method was applied to the determination of trace aluminum in various water samples,with good recoveries in the range of 96%-105% for spiked samples.