Adsorption of Cibacron Yellow F-4G dye onto activated carbons obtained from peanut hull and rice husk: kinetics and equilibrium studies

Abstract

The use of biomass residues from agricultural processes for the production of cheap and competitive activated carbon (AC) is an excellent option to minimize the costs of existing procedures to remove dyes from wastewater. In this study, the potential use of AC obtained from peanut hulls and rice husks for adsorption of Cibacron Yellow F-4G (CYF-4G) is examined. The activated peanut hull (PHAC) and rice husk (RHAC) were characterized by TGA, FTIR, BET and elemental analysis. The effects of different process variables as well as the dose of adsorbent, dye concentration and pH were evaluated. A decrease in amount of dye adsorbed per unit adsorbent mass was observed when increasing CYF-4G concentration. The results showed an optimal dye adsorption value at a pH of 2.0. The adsorption kinetics of CYF-4G are governed by the pseudo-second-order model. In addition, adsorption fits the Langmuir isotherm better than Freundlich's. Adsorption capacities of AC prepared from agricultural waste show that PHAC performs better than RHAC to remove CYF-4G.