Enhanced adsorption of Methylene Blue by EDTAD-modified sugarcane bagasse and photocatalytic regeneration of the adsorbent

Ethylenediaminetetraacetic dianhydride (EDTAD) modified sugarcane bagasse (SB) was prepared, and characterized by Fourier transform infrared spectroscopy (FTIR). Due to the presence of a large number of carboxyl groups, the adsorption capacity of the EDTAD-modified SB (EDTAD-SB) for Methylene Blue (MB) showed a significant increase compared with SB. The maximum adsorption capacity was 115.3 mg g(-1) for MB, according to the Langmuir equation. Kinetic studies showed better correlation coefficients for a pseudo-second-order kinetic model, confirming that the sorption rate was controlled by a chemisorption process. Photocatalytic regeneration of spent EDTAD-SB using UV/TiO2 is effective. Further, the regenerated EDTAD-SB exhibits 85% efficiency for subsequent adsorption cycle with MB aqueous solutions. (C) 2010 Elsevier B.V. All rights reserved.