Preparation Of Modified Sugarcane Bagasse And Its Application In Sugar Decolorization

A new adsorbent was prepared for sugar decolorization by the reaction betweensugarcane bagasse and epichlorohydrin/ethylenediamine. In this paper, the modificationparameters, structural characteristics, adsorption mechanism and the regeneration text ofmodified sugarcane bagasse was studied and the conclusions are as follows:The modification parameters were optimized as temperature of80oC, reaction time of5h,ethylenediamine content of27%and sodium bicarbonate content of1.5%, which yielded0.92%of nitrogen content in modified sugarcane bagasse.The performance of the modified sugarcane bagasse was characterized by X-raydiffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetryanalysis (TGA) and scanning electron micrographs (SEM). XRD analysis showed the crystalof cellulose was transformed from cellulose I to cellulose II by pretreatment. FTIR analysisindicated that the adsorption performance could be attributed to the graft of amine groups.Compared with raw sugarcane bagasse, modified sugarcane bagasse showed better thermalstability. SEM results showed the surface morphology was changed after modification. Theformation of a new intermolecular hydrogen bond after alkali treatment was discovered bycurve fitting method for OH stretching region.The decolorization parameters were optimized as modified sugarcane bagasse content of5.0g, pH of5, temperature of60oC and time of30min, which yielded58.63%ofdecolorization rate.Study of adsorption kinetics indicated that the process followed the pseudo-second-orderchemisorption model. The adsorption behavior was well described by the Freundlich isothermmodel, showing a multilayer capacity for colour compounds. Moreover, the regenerationstudies showed the adsorbent had a good reuse performance over several regeneration cyclesand the regeneration efficiency of adsorbent was decreased to86.17%after being regeneratedfor9times.