Synthesis of amino-modified ordered mesoporous silica as a new nano sorbent for the removal of chlorophenols from aqueous media

Contamination of natural water with organic pollutants is a problem of major concern and the demand for effective adsorbents for the removal of toxic compounds is increasing. Present work deals with the adsorption of 2-chlorpphenol (2-CP) and 2,4,6-trichlorophenol (2,4,6-TCP) from aqueous solutions on a new nano sorbent; amino-modified ordered mesoporous silica (APS-MCM-41) material. It was found that APS-MCM-41 shows significant adsorption for 2-CP and 2,4,6-TCP. This might be due to the acid and alkaline interactions among the amino functional groups and chlorophenols. Batch adsorption studies were carried out to study the effect of various parameters like adsorbent dose, pH, initial concentration and contact time. It was found that adsorption of 2-CP and 2,4,6-TCP depends upon the solution pH. From the sorption studies it was observed that the uptake of 2,4,6-TCP was higher than that of 2-CP. Freundlich and Langmuir adsorption isotherms were used to model the equilibrium adsorption data for 2-CP and 2,4,6-TCP. (C) 2009 Published by Elsevier B.V.