Adsorption Study of Anionic Dye, Eriochrome Black T from Aqueous Medium Using Polyvinyl Alcohol/Starch/ZSM-5 Zeolite Membrane

Abstract

Here we investigated the application of a novel polyvinyl alcohol/starch/ZSM-5 zeolite membrane as an adsorbent for the removal of Eriochrome black T (EBT) from aqueous medium. Physical and chemical structure of the membranes was characterized by scanning electron microscopy, optical microscopy, Fourier-transform infrared spectroscopy, X-Ray diffraction, thermogravimetric analysis and universal testing machine. Swelling measurement shows that with increase in zeolite content the hydrophobicity of the membrane also increases. Adsorption measurements were monitored spectrophotometrically at 530 nm. Results indicate that the operational parameters (initial dye concentration, zeolite dosage, temperature, pH and contact time) has significant influence on the adsorption behavior of the membrane. The maximum adsorption capacity was estimated to be 2.17 mg/g for 5 wt% zeolite loaded membrane at an initial concentration of 10 mg/L, at room temperature and at pH 3. Adsorption kinetics analysis revealed that pseudo-second-order model describes the adsorption of EBT onto PVA/starch/ZSM-5 zeolite membrane with correlation coefficient close to one. Adsorption isotherm was analyzed using Langmuir and Freundlich isotherm models and the result shows that adsorption follow Freundlich isotherm model. Adsorption–desorption studies suggests that the membrane possess good regeneration capacity.