Title
Synthesis and properties of treated waste cellulose and GMA grafted composite to remove different acid dyes from aqueous solutions
Authors
NABIL A. EL-KELESH and GHADA A. MAHMOUD

Received July 13, 2013
Published Volume 49 Issue 9-10 October-December
Keywords gamma-irradiation, composite, waste cellulose, grafting, dye adsorption

Abstract
The present study investigated the alkali treatment of waste cellulose (Cell) and its grafting with glycidyl methacrylate monomer (GMA) using gamma rays of Co60 source and a solvent mixture of methanol/H2O. The obtained Cell/GMA composite was assessed as to its efficiency as a sorbent for the removal of acid dye contaminants from wastewater. Various concentrations of GMA and irradiation doses were used to determine the optimum grafting conditions of the composite. The characterization the Cell/GMA composite was done by scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and infrared spectrometer analysis (FTIR). The ability of the composite to absorb water was studied as a function of GMA concentration, irradiation dose and pH of the medium. The efficiency of Cell/GMA in removing several acid dyes (such as acid fast yellow, λ = 404 nm, acid methyl blue, λ = 620 nm, and acid methyl green, λ = 597 nm) from aqueous solutions was investigated. The effect of parameters such as medium pH and GMA monomer content in the grafted composite on the dye removal efficiency was studied. The adsorption isotherm was well described by the Freundlich equation and the empirical constants n and k were calculated. It was found that the adsorption capacity of Cell/GMA was high at relatively low temperature, which means the adsorption is exothermic in nature and the heat change (∆H) of adsorption was calculated using the Arrhenius equation. These results show that the Cell/GMA composite can be used as a sorbent for the removal of acid dye contaminants from wastewater and can be successfully employed in wastewater treatment.