Removal of cationic and anionic dyes from aqueous phase by Ball clay – Manganese dioxide nanocomposites

We report novel method to synthesis of Ball clay – Manganese dioxide nanocomposite (BC-MNC) as an effective and eco-friendly adsorbent for the removal of malachite green(MG) and acid blue 25 (AB25) from its aqueous solution. The as synthesized BC-MNC was characterized using powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), zeta potential analysis, Brunauer−Emmett−Teller (BET) surface area analysis, Barrett-Joyner-Halenda (BJH) pore size and volume analysis. Many factors such as pH, adsorbent dose, temperature, contact time and initial dye concentrations were optimized to control the adsorption process of MG and AB25 onto BC-MNC. The optimum conditions for removal of MG were found to be pH = 8, adsorbent dose =0.8 g, contact time =70 min and similarly for AB25 was found to be pH = 2, adsorbent dose =0.8 g and contact time =80 min. The equilibrium isothermal data was finely fitted with Langmuir isotherm model for MG and Freundlich isotherm model for AB25. The kinetics data of both MG and AB 25 followed the pseudo-second order kinetics. The thermodynamics factors revealing that the adsorption process of MG was spontaneous and endothermic, and the adsorption of AB25 was spontaneous and exothermic in nature. Moreover, maximum adsorption capacity of BC-MNC for the removal of MG and AB25 was found to be 58.47 mg/g and 1250 mg/g respectively. Thus, the ...
Source: Journal of Environmental Chemical Engineering - Category: Chemistry Source Type: research