Effective Adsorptive Removal of Brilliant Green Dye from Aqueous Solution by Bentonite and Acid-activated Bentonite

Abstract

In the present work, Adsorption of Brilliant Green (BG) from aqueous solutions via batch sorption experiments onto Yemen bentonite (YB) and Acid-activated bentonite (A-AYB) has been investigated. Studies concerning the factors influencing the adsorption capacities of YB and A-AYB for example: adsorbent dosage, initial dye concentration, pH, ionic strength, temperature and contact time were systematically studied and discussed. The results show that YB demonstrated high adsorption capacities toward basic dyes while A-AYB exhibited sorption capacities lower than YB. The kinetics data were analyzed using first order and pseudo-second order models. The isotherm data were investigated accord­ing to Langmuir and Freundlich equations. Thermodynamic parameters ΔG°, ΔH° and ΔS° were calculated for the adsorption of BG on YB and A-AYB; the value of ΔG° showed the spontaneous nature of adsorption for both sorbents.