In this work will be produced cellulose nanofibers from soybean by-products (straw and bean pods) by chemical hydrolysis coupled to a mechanical treatment by ultrasound. Initially will be determined the bleaching/delignification methodology of soybean by-products (straw and bean pods) to obtain a fraction rich in cellulose. This fraction will be subjected to chemical hydrolysis with sulfuric acid. The sulfuric acid concentration, temperatures, and reaction time will be investigated to determine the best conditions for obtaining cellulose nanofibers. First, the material will be drying and milling using slicer and cryogenic mill. This material will be subject to bleaching/delignification using three methodologies. When determined the bleaching/delignification methodology that allows separating larger amounts of lignin and hemicellulose, the chemical hydrolysis will be performed. Two concentrations of sulfuric acid (1 % and 6% ) and two temperatures (50ºC and 85 ° C) will be tested. Kinetics of chemical hydrolysis will be obtained for these conditions according to the reducing sugars concentration and zeta potential (particle size and surface charge). The lignocellulosic composition will be evaluated by HPLC. The nanofibers produced will be characterized according to their crystallinity by X- ray diffraction and their morphology by transmission electron microscopy (TEM).
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