2-羟基-3-(三乙胺基)丙基正癸基硫醚修饰碳糊电极测定痕量金

Voltammetric Determination of Trace Gold(Ⅲ)at A Carbon-paste Electrode Modified with2-Hydroxy-3-(triethylamino)propyl n-Decyl Thioether

制备了2＿羟基＿3＿(三乙胺基)丙基正癸基硫醚修饰碳糊电极,用于痕量金的测定。研究了电极的伏安特性及分析条件。在0.2mo／LKCl-HCl缓冲溶液中(pH1),Au(Ⅲ)被富集到电极表面,然后介质交换到0.2mol／LKCl-HCl空白溶液中(pH1)进行阳极溶出伏安测定,对于5min富集,Au(Ⅲ)浓度在2×10-8～1×10-6mol／L范围内呈线性关系,检出限为1×10-8mol／L,相对标准偏差5.2%,一般常见离子不干扰。

A carbon_paste electrode modified with2_hydroxyl_3_(triethylamino)propyl n_decyl sulfide(HTPDT)was prepared for the determination of trace gold.The cyclic voltammetric characteristics and the analytical conditions of the electrode were studied.The gold(Ⅲ)ion was pre_concentrated on the surface of the modified electrode in a buffer solution of0.2mol·L -1 KCl-HCl(pH1),and then determined in a cell containing0.2mol·L -1 KCl-HCl blank solution(pH1).This electrode gave good linearity in the range of2×10 -8 ～1×10 -6 mol·L -1 with a detection limit of1×10 -8 mol·L -1 .The method has been applied to the determination of gold in mineral samples,and satisfactory results were obtained.