锌(Ⅱ)-2-(6-甲基-2-苯并噻唑偶氮)-5-二乙氨基苯甲酸的显色反应研究

Study on the Colour Reaction of Zinc(Ⅱ) with 6-CH_3-BTAEB

研究了2-（6-甲基-2-苯并噻唑偶氮）-5-二乙氨基苯甲酸（6-CH3-BTAEB）与锌显色反应的溶剂化效应和缓冲介质的影响。结果表明，在乙醇介质中，6-CH3-BTAEB与锌（Ⅱ）在（CH2）6N4-HNO3缓冲体系中可形成摩尔比为2：1的蓝色络合物。该络合物的最大吸收波长为626nm，表观摩尔吸光系数ε626=7．7×10^4L·mol^-1·cm^-1，锌（Ⅱ）含量在0～8μg／10mL范围内遵守比耳定律。方法用于镁舍金和模拟合金试样中痕量锌的测定，结果满意。

In this paper, the effect of organic solvent and buffer on colour reaction of zinc with 6-CH3- BTAEB has been studied. In （CH2）6N4-HNO3 buffer solution, 6-CH3-BTAEB reacts with zinc（ Ⅱ ） in the presence of ethanol to form blue violet 2：1 complex with apparent molar absorptivity of 7.7 × 10^4 L·mol^-1·cm^-1 at 626 nm. Beer＇s law is obeyed in the range of 0～8 μg/10 mL zinc（ Ⅱ ）. The proposed method has been applied to the determination of zinc in magnesium alloy and analog alloy with satisfactory result.