对羧基苯基荧光酮与铝显色反应的研究及应用

Study on color reaction of p-carboxylphenylfluorone with alnmininm and its application

研究新试剂对羧基苯基荧光酮与铝的显色反应,建立测定镁合金中微量铝的光度分析方法。在pH5.7的乙酸铵缓冲溶液和阳离子表面活性剂十六烷基三甲基溴化铵(CT- MAB)存在下,铝与对羧基苯基荧光酮发生灵敏的显色反应,生成稳定的红色络合物。铝络合物最大吸收峰位于573 nm,表观摩尔吸光系数达1.37×10~5L·mol^(-1)·cm^(-1),0～0.24μg/mL铝符合比尔定律。显色反应体系具有良好的选择性,绝大多数金属离子允许量较高,尤其是镁。该方法已用于镁合金中微量铝的测定,结果令人满意。

A new method was developed for spectrophotometric determination of trace aluminium in magnesium alloy,based on the color reaction of p-carboxylphenylfluorone with aluminium（Ⅲ）. In ammonium acetate solution（pH5. 7） and in the presence of cationic surfactant CTMAB,aluminium reacts with p-carboxylphenylfluorone sensitively to form a red complex. The complex has a maximum absorption at 573nm,with apparent molar absorptivity of 1.37×10^5L·mol^-1·cm^-1,0～0.24μg/mL. Beer＇s law is obeyed in the range of 0-0. 24μg/mL for aluminium. The color reaction system has good selectivity too. Most of metal ions studied can be tolerated in considerable amounts, especially magnesium. Proposed method has been applied to direct determination of aluminum in magnesium alloy samples with satisfactory results.