Obtenção de nanocelulose via hidrólise ácida a partir dos resíduos da produção de cerveja

Abstract

The industrial waste usage for technological application has been gaining ground in different segments and applications. One of the prominent sectors is Material technology, where these residues can be used to obtain the raw material for obtaining polyols, which, later on, will be used in the process for obtaining polymeric materials or as fillers and reinforcement in thermoplastic polymeric materials. The cellulose, which is a natural polymer and the material generated in greater amounts in nature, is been used as a source of study and has several applications in materials, such as reinforcement, load or chemical surface modifications. The nanocellulose, which is obtained from different chemical, mechanical and biological processes, may be in the form of cellulose nanofibrils (NFCs), which are present in crystalline and amorphous regions along it, and cellulose nanocrystals (NCCs) where it reveals only the crystal region. The material in this work is malt bagasse, which is currently the waste generated in the beer industry by bulk and shows no alternative reuse and application in Material technology. It was determined the chemical composition of the fibers and applied chemical bleaching process to remove components such as lignin and hemicellulose in preparation of the fibers for obtaining nanocellulose through acid hydrolysis. Hydrolysis was performed using H2SO4 at two concentrations, 44% (w / w) and 64% (m / m), with the temperature at 40 ° C and 50 ° C for the samples subjected to the acid solution 44%, besides that, it was used 40 ° C, 50 ° C and 60 ° C for samples with 64% solution. For the samples 44/40 and 44/50 it were obtained NFCS and for the 64% the result obtained was NCCs. Natural and bleached fibers, along with nanocellulose, obtained through different concentrations of H2SO4 and temperature variations were characterized by Fourier Transform Infrared Spectroscopy (FTIR), Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM) and Field Emission Scanning Electron Microscopy (FESEM), X-Ray Diffraction (X-RD) and Thermogravimetric Analysis (TGA).