Equilibrium Modeling and Kinetic Studies on the Adsorption of Basic Dye by a Low Cost Adsorbent

Document Type : Research Paper

Authors

• Zohreh Saadati ¹
• Anita Makvandya ²

¹ aDepartment of Chemistry, Islamic Azad University, Omidiyeh Branch, Omidiyeh, Iran

² Department of Chemistry, Islamic Azad University, Omidiyeh Branch, Omidiyeh, Iran

Abstract

An agricultural waste and eco-friendly biosorbent i.e. rice husk has been used as a cheap adsorbent
for the removal of methylene blue dye from aqueous solutions. The physical properties of the developed
adsorbent were characterized using FTIR. The study was realized using batch experiments. The effects
of contact time, pH, initial dye concentration, biosorbent dose and temperature were investigated. The
adsorption data were evaluated by Freundlich and Langmuir isotherm models. The adsorption isotherm is
best fitted by the Freundlich model, while the adsorption kinetics is well described by the pseudo-secondorder
model. Different thermodynamic parameters i.e., changes in standard free energy, enthalpy and
entropy have also been evaluated and it has been found that the dye adsorption onto rice was a spontaneous,
endothermic and physical reaction.

Keywords

• Rice Husk
• Biosorption
• Kinetic study
• Isotherm
• Methylene Blue
• basic dye

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