Study of Adsorption of Copper Ions on Functionalized MCM-41 by Experimental methods and Molecular Dynamic Simulations

Copper is an essential element at the trace level (i.e. catalytic action in heme synthesis) [1], but the intake of large quantities can be toxic. So the techniques, such as ion exchange, precipitation, adsorption, membrane processes, electro-dialysis, have been employed for removing heavy metals from wastewater [2]. Adsorption is an effective and economic method for removing heavy metals from wastewater. The mesoporous molecular sieves with MCM-41 type structures were applied for the adsorption of metal ions from aqueous solutions [3]. In this work, a functionalized MCM-41with amine and furfuran groups have been prepared and used for removing Cu2+ from aqueous solutions. The MCM-41 mesoporous was synthesized and the surface of MCM-41was functionalized with NH2 by 3-aminopropyl-trimethoxysilane and 3-(2-aminoethylamino) propyl-trimethoxysilane. Afterwards, the Furfuran functional group was stabilized on MCM-41-NH2. The synthesized structures were characterized by FT-IR, BET, UV-Visible and XRD spectroscopy methods. We have used this functionalized MCM-41 to elimination of copper ions from water. In order to determine the concentration of acquired ions from the filtrated solution, the flame atomic absorption spectrometry (FAAS) was utilized. The effect of some variables like adsorbent quantity, time of reaction, pH and temperature was investigated. The results show that, the adsorption capacity of Cu2+ on the modified MCM-41 with Furfuran is 3.8 mgCu/g. The Adsorption properties of metal ions on MCM-41 [4] and on modified MCM-41 by different organic groups (chloropropyl, phenyl, benzyl, mercaptopropyl, cyanopropyl, butyl groups) were calculated based on grand canonical Monte Carlo (GCMC) simulation [5]. We have study the adsorption properties of functionalized MCM-41 structure by molecular dynamics (MD) simulation.The spectral properties and adsorption isotherms of Cu+2 adsorbed in functionalized MCM-41 were calculated based on grand canonical Monte Carlo (GCMC) simulation. Equilibrium modeling of the adsorption showed that the adsorption of Cu2+ ions was fitted to a Freundlich isotherm. The qualitatively consistent results of molecular dynamics simulations with experiments suggest the possibility of applying computer simulation for preliminarily selection of adsorbent functional groups for removal of Cu2+.