Use of the enzymatic hydrolysis residue of sugarcane straw pretreated with dilute acid for the production of composites

This study aimed to reuse the solid residue of the enzymatic hydrolysis of sugarcane straw pretreated with diluted acid in order to obtain composites. For this purpose, sugarcane straw was submitted to the pretreatment with H₂SO₄ (1% w/V) at 120 ° C for 20 minutes. Then, the pretreated material was delignificated with NaOH 1% (w/V) at 100 ° C for 1 hour. The in natura straw, pre-treated and the pulp obtained were chemically characterized to determine the content of cellulose, hemicelluloses and lignin were then subjected to enzymatic hydrolysis, which was carried out using a commercial cellulase Celluclast 1.5 L, supplemented by β-glycosidase (Novozym 188). And to observe the structural changes in the fiber after each step was performed a Scanning Electron Microscopy (SEM). The pretreated sugarcane straw has approximately 42% cellulose and the pulp obtained has 52% cellulose. The enzymatic conversion obtained for the pre-treated straw was 60% whereas for the pulp obtained, the conversion was around 89%. The solid residue obtained after enzymatic hydrolysis was used as reinforcement in composites of polyurethane with three different proportions of residue: 10, 15 and 20 %. Water absorption tests and differential scanning calorimetry (DSC) of the composites obtained are underway.