Adsorption of methyl green onto zeolite ZSM-5(pyrr.) in aqueous solution

Abstract

In this work we report the preparation of ZSM-5 (pyrr) with molar composition: 0.2057Na2O - 0.00266Al2O3 - SiO2-0.68Pyrr (pyrrolidine) - 40 H2O - 0.12H2SO4 by hydrothermal synthesis method. The sample is characterized using IR spectra, MEB and XRD. The removal of Methyl Green (MG) dye from aqueous solutions onto ZSM-5(pyrr.), is examined under various experimental conditions (dyes concentration, amount H-ZSM-5(pyrr.), temperature, pH and contact times).The adsorbed amount increased with increasing amount dye, amount H-ZSM-5(pyrr.), time, temperature and PH. The linear correlations of Langmuir and Freundlich isotherms are determined. The experimental results show that we have model Langmuir. Free energy "G° enthalpy "H°, entropy "S° and activation energy Ea are determined. The "H°, "G° and Ea values indicated that the adsorption of methyl green dye onto H-ZSM-5(pyrr.) is exothermic physisorption process. Kinetics analyses are conducted using pseudo first-order, second-order and the intraparticle diffusion models. The results showed that the adsorption kinetics was controlled by a pseudo second-order model.