Evaluación de diferentes métodos de extracción para la obtención de nanofibras de celulosas puras a partir del raquis de banano

Abstract

The development of materials from waste is a sustainable alternative to reduce pollution, because they take advantage of this waste by giving it a new use. The present research work focuses on the evaluation of the different extraction methods to obtain pure cellulose nanofibers from the banana rachis, from which biological, physical and chemical extraction methods were applied. In the chemical method, alkaline treatment with NaOH was performed, followed by bleaching with NaOH+H2O2 and finally acid hydrolysis with HCl. In the biological method, the fungus Trichoderma spp was used to inoculate the banana rachis; in the physical treatment in he employed the use of a hydrothermal reactor, thus submerging the banana rachis together with NaOH. In the biological method, the fungus Trichoderma spp was used to inoculate the banana rachis; in the physical treatment in he employed the use of a hydrothermal reactor, thus submerging the banana rachis together with NaOH. The cellulose nanofibers obtained were classified as follows: NCF-BFQ (combination of methods: biological retting, steam explosion and chemical treatment), NCF-FQ (application of methods: steam explosion and chemical treatment), NCF-BQ (union of methods: biological retting and chemical treatment) and NCF-Q (by chemical treatment), these methods were combined to evaluate their effectiveness and characterize them. The characterization was carried out by determining the zero-charge potencial pHpcc, Fourier transform infrared spectrophotometry (FTIR) for the identification of the functional groups present in NCFs, Scanning Electron Microscopy (SEM) to determine the morphology of NFCs and analysis of economic feasibility (production costs). According to FTIR spectra, the NFC-BQ method shows the lowest stretch in the range of 1600 cm ⁻¹ to 800 cm ⁻¹, compared to the other methods. This suggest that the NCF-BQ method has the lowest concentration of cellulose and lignin, as peaks associated with these componentes are less prominent in the spectrum. Although combined methods can offer advantages in terms of purity and specific characteristics of nanofibers, the chemical method remains the most cost-effective for large-scale NFC production.