Synthesis of Sodium Alginate-Derived Carbon Aerogel for Adsorptive Removal of Methylene Blue

Abstract

In this study, carbon aerogel was prepared from sodium alginate via the sol-gel technique. The morphological study clearly revealed that the synthesized aerogel possessed a highly porous structure with a specific surface area of 470 m2/g. The applicability of the aerogel as an adsorbent was examined in methylene blue removal. Adsorption isotherms, kinetics, and thermodynamic studies of Removal of MB from aqueous solutions were conducted in a batch system. The effect of pH and adsorbent dosage on the adsorption of MB was investigated. The equilibrium data were best fitted to the Langmuir model with a maximum adsorption capacity of 70.42 mg/g. The adsorption kinetics of MB followed the pseudo-first-order models. Thermodynamic analysis of the results indicated that adsorption is a physical process and is in agreement with data obtained from the Dubinin−Radushkevich isotherm model. The removal of the MB process was spontaneous and endothermic.

Keywords

• carbonaceous aerogel
• methylene blue
• adsorption model
• kinetics