3-甲氧基-甲亚胺H分光光度法测定镓(Ⅲ)

Spectrophotometric determination of gallium(Ⅲ) with 3-methoxy-azomethine H

研究了由十六烷基三甲基溴化铵（CTMAB）、正丁醇、正庚烷和水自制微乳溶液存在下，3-甲氧基-甲亚胺H与Ga（Ⅲ）的显色反应，建立了分光光度法测定微量镓的新方法。结果表明，在pH5．90的HAc-NaAc缓冲溶液中，Ga（Ⅲ）与试剂形成摩尔比为1：1的淡黄色络合物，络合物的最大吸收峰在440nm，表观摩尔吸光系数ε为1．60×10^5L·mol^-1·cm^-1。在10mL显色液中，Ga（Ⅲ）量在0．04～4．2μg范围内符合比尔定律，检出限为0．013μg／mL。方法已用于煤和矿石中微量镓的测定，回收率为103．2％～104．6％，相对标准偏差为4．70％～4．80％。

The color reaction of the reagent 3-methoxy-azomethine H with gallium（Ⅲ） in the presence of cetyltrimethylammouium bromide （CTMAB）, n-butanol, heptanol and water microemulsiom were studied, and a new spectrophotometric method for the determination of trace Ga（Ⅲ） has been established. Results show that the new color reagent reacts with Ga（Ⅲ） to form a stable light yellow complex （mole ratio 1 ： 1） in the presence of HAc-NaAc buffer solution at pH 5.90. The maximum absorption wavelength and apparent molar absorptivity are 440 nm and 1.60×10^5L·mol^-1·cm^-1 respectively. Beer＇s law is obeyed in the range of 0.04-4.2 μg in 10 mL chromogenic liquor, and the detection limit is 0. 013 μg/mL. The method has been applied to the determination of Ga（Ⅲ） in the coal and ore samples with the RSD of 4.70%-4.80% and the recovery of 103.2%-104.60%