Adsorption and Optimization Studies of Congo Red from Solution Using Montmorillonite-Silica Nanocomposite

Congo red was removed on Montmorillonite-silica nanocomposite from solution by adsorption process. The adsorption parameters studied were adsorbent dose, initial concentration and contact time. The optimum adsorption parameters were found to be 2 mg/L, 1.5 g and 40 minutes for initial concentration, adsorbent dose and contact time respectively with removal percentage of 84.10%. Pseudo first and second order kinetics were used for the studies. Pseudo second order best fit the adsorption process with R2 = 1 than the Pseudo first order which has R2 = 0.933. Experimental data were best fitted by the Langmuir Isotherm with R2 =0.9024 other than the Freundlich Isotherm, R2 =0.568. The RL of 0.994 of the Langmuir isotherm shows the favourability of the adsorption process. The maximum adsorption capacity by Langmuir isotherm was found to be 172. 40 mg/g.