Preparation of chelating agents from sugarcane bagasse by microwave radiation as an alternative ecologically benign procedure

Abstract

Microwave radiation was utilized to produce neutral chelating agents (BCA) from sugarcane bagasse. BCA were prepared by reaction of urea with reactive sites present in bagasse such as hydroxyl and carboxylic groups. BCA prepared through microwave radiation had slightly lower yield (83%) compared to the conventional oven-drier process (87%). BCA demonstrated maximum chelating adsorption capacity (Q_max) of 1.2 mmol g⁻¹ for Cu(II) at pH of 5.5 and 1.4 mmol g⁻¹ for Hg(II) at pH 6.0. These results could be comparable with the Q_max of 1.46 mmol g⁻¹ for Cu(II) and 2.4 mmol g⁻¹ for Hg(II) obtained from Duolite GT-73, a commercial chelating resin, macroreticular with tiol (S–H) functional groups.