Effectiveness of derived oka activated carbon coated with magnesium oxide in removal of bromocresol green: Isotherms and kinetics

Abstract

Introduction: Protection of environment and water resources implies an urgent need for removal of dyes from textile wastewater. The aim of study was to evaluate the effectiveness of derived Oka activated carbon coated with magnesium oxide in removal of bromocresol green (BG) from aqueous solution. Methods: Activated carbon was derived from Oak and coated with magnesium oxide. The prepared carbon was used for removal of BG from aqueous solution. Effect of various variables such as initial pH, contact time, adsorbent dosage and initial dye concentration was investigated. The adsorption equilibrium was demonstrated with Langmuir and Freundlich and Temkin isotherm models. Results: Results showed that the maximum removal rate of BG (92.6) was obtained in pH=3, contact time=4 min, adsorbent dosage of 4 g/l and dye concentration of 20 mg/l. The Freundlich isotherm model fitted well with the experimental adsorption data (R2=0.9969). The adsorption kinetic equations of pseudo-first order, pseudo-second order were used to model the experimental data as function of contact time. The experimental adsorption data best correlated to pseudo-second order model (R2=0.9955). Conclusion: The modified activated carbon used in this study can be applied as effective adsorbent for removal of dye in aqueous solution. © 2019, Shahroud University of Medical Sciences. All rights reserved.