Comparison of the efficiency of Cu and silver nanoparticle loaded on supports for the removal of Eosin Y from aqueous solution: Kinetic and isotherm study

In this study, the efficiency of a novel copper containing ionic liquid based nanoporous organosilica (Cu@IL-ONO) and palladium nanoparticles loaded on activated carbon (Pd-NP-AC) for the removal of Eosin Y from aqueous solution was investigated. The Cu@IL-ONO was prepared by hydrolysis and co-condensation of tetramethoxysilane (TMOS) and 1,3-bis (trimethoxysilylpropyl) imidazolium chloride in the presence of surfactant template following immobilization of copper chloride dihydrate. These materials were characterized by nitrogen adsorption-desorption analysis and scanning electron microscopy (SEM) and subsequently used for the successful removal of Eosin Yellow (EY) from aqueous solution. The effects of pH, contact time, amount of adsorbents, initial dye concentration was optimized and set as following: 0.005 g/50 mL Cu@IL-ONO and 0.015 g/50 mL Ag-NP-AC at pH = 2 for Cu@IL-ONO and pH = 3 for Ag-NP-AC and contact time less than 14 min. The experimental removal percentage data at various situations was fitted by conventional isotherm models like Langmuir, Freundlich, Tempkin and Dubinin-Radushkevich (D-R). Judgment based on linear regression coefficient (R-2) and error analysis show high usability of the Langmuir isotherm for best explanation of experimental data with maximum monolayer adsorption capacities 286 and 250 mg g(-1), at room temperatures for Cu@IL-ONO and Ag-NP-AC, respectively. Fitting the corresponding data of removal percentage at various experimental conditions shows the suitability of second order and interparticle diffusion model for interpretation of real data. (C) 2013 Elsevier B.V. All rights reserved.