本文以电化学活性的玫红酸钠修饰碳糊电极,利用玫红酸盐与钡离子的络合效应,实现钡离子的电化学固相微萃取.以循环伏安法研究了钡离子的固相微萃取及其最佳实验条件.固相微萃取的动力学符合S形曲线模型,获得表观一级反应速率常数为2.183 min-1.固相微萃取的热力学遵循Freundlich等温吸附模型,吸附常数为n=11.4,k=1.025.%Electrochemical solid phase microextraction is a powerful tool in sample pretreatment, and can be used in the electrochemical detection of electrochemically inactive substances. In the present paper, Barium ion was extracted electrochemically on a sodium rhodizonate modified carbon paste electrode based on the coordination interaction between sodium rhodizonate and Barium ion. The extraction process and its optimal experimental conditions were studied by cyclic voltammetry. The extraction kinetics follows a sigmoidal model with the apparent first order kinetic constant of 2. 183 min~'. The isothermal follows a Freundlich model with the thermodynamic adsorption constants of n=11.4,l=1. 025. This study offers a basic data for the electrochemical determination of barium cation.
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