Adsorption of Methylene Blue dye by Synthetic Zeolite Na-A and Standard Zeolite 4A

Abstract

This study investigated the adsorption ability of methylene blue dye by the zeolite Na-A synthesized from water treatment sludge and the standard zeolite 4A.  The effects of adsorbent dosage, contact time, initial methylene blue concentrations, solution pH and optimal experimental conditions were investigated. The adsorption isotherms were analyzed by using Langmuir and Freundlich equations. The experimental results recommended the optimum adsorbent dosage and contact time of synthetic zeolite Na-A were 1 g and 60 min, respectively. At the optimum conditions, the adsorption percent of synthetic zeolite Na-A and zeolite 4A was more than 90 and 18 percent, respectively. Adsorption capacities of each zeolite in range of pH 3-9 were similar. The results found that the experimental data of isotherm followed the Langmuir isotherm model better than the Freundlich model. The maximum adsorption capacities obtained from Langmuir isotherm of synthetic zeolite Na-A and standard zeolite 4A were 40.67 and 7.85 mg/g, respectively. Therefore, the synthetic zeolite Na-A synthesized from water treatment sludge could be a good adsorbent for methylene blue dye removal.