Synthesis and characterization of SnO2/(NH4)2‐SnCl6 nanocomposites loaded on activated carbon and its application for adsorption of methylene Blue and Orange G

Abstract

The present study deals with the synthesis and characterization (FE‐SEM, particle size distribution, XRD and point of zero charge) SnO2/(NH4)2‐SnCl6 nanocomposites loaded on activated carbon (SnO2/(NH4)2‐SnCl6‐NCs‐AC) and its subsequent application for the simultaneous removal of Methylene Blue (MB) and Orange G (OG) from aqueous solution. Response surface methodology (RSM) based on central composite design (CCD) give trend of influencing responses with respect to five parameters such as contact time (X1), OG concentration (X2), MB concentration (X3), adsorbent mass (X4) and pH (X5). In later stage following recognition of significant variables and interaction, quadratic model generated which are able to predict the dyes removal in different conditions. Justification and selection of significant terms was conducted based on analysis of variance and Fisher's F‐test Optimal value of contact time, OG concentration, MB concentration, adsorbent mass and pH were set at 4.0 min, 10 mg l−1, 20 mg L−1, 0.015 g and 6.0, respectively, which lead to achievement of best experiment removal percentage of 97.0 and 99.5% OG and MB respectively, from their binary solutions. The whole experimental data follow pseudo‐first‐order and pseudo‐second‐order rate equations. The fitting experimental data to more available conventional model like Langmuir, Freundlich, Temkin and Dubinin‐Radushkevich isotherm models revel more ability of Langmuir model (with R2 > 0.997) for explanation of system in equilibrium. The adsorption efficiency remained high even after the five cycle of reuse (99.76% and 95.56% for MB and OG, respectively).