Evaluación de un electrodo de carbón vítreo modificado con Zeolita tipo “A” en la adsorción de 2-clorofenol

• Main Authors: Aurora Molina, Carlos Villavicencio, Lenys Fernández
• Format: Article
• Language: English
• Published: Universidad de Los Andes 2009-10-01
• Series: Avances en Química
• Subjects: zeolite-modified electrodes; 2-chlorophenol oxidation; preconcentration
• Online Access: http://www.saber.ula.ve/bitstream/123456789/29513/5/artic2.pdf

Glassy carbon electrodes modified with Zeolite “A” were studied in order to evidence the adsorption of 2-chlorophenol. Synthesis of zeolite was undertaken by a hydrothermal method using calcined kaolin as raw material. The zeolite was first exchanged with calcium ions. Then, it was modified with the cationic surfactant CTAB (cetyl trimethyl ammonium bromide) or the non-ionic surfactant Triton X-100 (t-octylphenoxy-polyethoxyethanol). Adsorption of 2-chlorophenol was evaluated by cyclic voltammetry, once it was adsorbed onto the modified electrode. Electrochemical results indicated that the films surfactant-zeolites were able to adsorb the 2-chlorophenol from an aqueous alkaline medium. The best results were achieved when the cationic surfactant CTAB was used. The importance of electrode surface cleaning to guarantee the complete adherence between the vitreous carbon and the modified surfactant zeolite was determinated. Polishing and cleaning processes depend on the type of surfactant used.