Extração de nanocristais de celulose da fibra da vagem de amendoim (Arachis hypogaea)

Abstract

Faced with the environmental problems related to plastic recycling and the depletion of fossil resources, the interest in sustainable materials, such as the use of natural fibers in the manufacture of composites for the replacement of fiberglass and plastic, arose. A source of natural fibers is the peanut pod, which is an abundant agroindustrial residue. To avoid the inappropriate disposal of agroindustrial residues, which generate damages to the environment, an alternative is the use for extraction of cellulose nanocrystals and application in coverings and reinforcement materials. The present work carried out the extraction of cellulose nanocrystals from the peanut pod through the processes of mercerization and bleaching in order to remove some components present in the fiber with lignin and hemicellulose. The fiber was submitted to pre - treatments and delignification by chemical treatments and then analyzes of X - ray Diffraction and Infrared Spectroscopy with Fourier Transform. Subsequently, the fiber was treated with acid hydrolysis with variation of times and temperatures, performing nine experiments through the experimental design of the central rotational compound 22 for the extraction process of cellulose nanocrystals. After extraction, the yield of the cellulose nanocrystals was quantified. Through the fiber analysis it was observed that removal of the components was effective. There was extraction of cellulose nanocrystals in all assays, however, the highest yield was through assay 1 with 86.81% in the time of 30 ° C and 30 minutes. In this way, the fiber has potential for use due to its high cellulose content.