2,4二羟基苯甲醛缩氨基硫脲与铜Ⅱ的显色反应及应用

Spectrophotometric study on the color reaction of 2,4-dihydroxybenzaldehyde thiosemicarbazone with copper and application

研究了新显色剂 2 ,4 二羟基苯甲醛缩氨基硫脲 (DBT )与铜的显色反应 ,建立了光度法测定微量铜的新方法。在pH5 2 的HAc NaAc缓冲溶液中 ,Cu2 + 与DBT形成一种稳定的摩尔比为 1:1的黄色络合物 ,其最大吸收波长位于 3 66 2nm处 ,表观摩尔吸光系数为 2 3 7× 10 4 。Cu2 + 量在 0 1～ 2 0mg/L范围内服从比尔定律 ,相关系数r =0 9993。将该法应用于铝合金和人发中微量铜的测定 。

A new method for the spectrophotometric determination of trace copper with 2,4 dihydroxybenzaldehyde thiosemicarbazone(DBT) is reported in this paper.In the medium of HAc NaAc buffer solution at pH5.2,DBT reacts with copper to form a stable complex and the maximum absorbance is at 366.2nm with an apparent molar absorptivity of 2 37×10 4L·mol -1 ·cm -1 ,Beer's law is obeyed in the concentration range of 0 1-2 0mg/L for Cu 2+ The method has been satisfactorily applied to the determination of copper in aluminum alloy and human hair.