title: Isolation and characterization of lignocellulose nanofibers from different wheat straw pulps.
abstract: Wheat straw was cooked under different pulping processes: Soda (100°C, 7% NaOH, 150min), Kraft (170°C, 16% alkalinity, 25% sulfidity, 40min) and Organosolv (210°C, 60% ethanol, 60min). Once the pulps were obtained, lignocellulose nanofibers (LCNF) were isolated by mechanical process and TEMPO-mediated oxidation followed by a high pressure homogenization. After pulping process, the different pulps were characterized and its chemical composition was determined. The pulps characterization indicates that the Soda process is the process that, despite producing less delignification, retains much of the hemicelluloses in the pulp, being this content a key factor in the nanofibrillation process. Regarding the LCNF obtained by mechanical process, those nanofibers isolated from Organosolv wheat pulp (OWP) and Kraft wheat pulp (KWP) show low values for nanofibrillation yield, specific surface area and greater diameter. However, those nanofibers isolated from Soda wheat pulp (SWP) reach much higher values for these parameters and presents a diameter of 14nm, smaller than those obtained by TEMPO-mediated oxidation from OWP. Smaller diameters are generally obtained in TEMPO-oxidized LCNF. This work concludes that the lignin content does not affect greatly to obtain LCNF as does the hemicellulose content, so it is accurate to use a soft pulping process.
authors: Chemical Engineering Department, Faculty of Science, University of Córdoba, Building Marie-Curie, Campus of Rabanales, 14014 Córdoba, Spain.
authors: Rafael
authors: R
authors: Sánchez
authors: Chemical Engineering Department, Faculty of Science, University of Córdoba, Building Marie-Curie, Campus of Rabanales, 14014 Córdoba, Spain. Electronic address: eduardo.espinosa@uco.es.
authors: Eduardo
authors: E
authors: Espinosa
authors: Chemical Engineering Department, Faculty of Science, University of Córdoba, Building Marie-Curie, Campus of Rabanales, 14014 Córdoba, Spain.
authors: Juan
authors: J
authors: Domínguez-Robles
authors: Chemical Engineering Department, Campus "El Carmen'', University of Huelva, Av. 3 de Marzo s/n, 21071 Huelva, Spain.
authors: Javier Mauricio
authors: JM
authors: Loaiza
authors: Chemical Engineering Department, Faculty of Science, University of Córdoba, Building Marie-Curie, Campus of Rabanales, 14014 Córdoba, Spain.
authors: Alejandro
authors: A
authors: Rodríguez
mesh_terms: D008031:Lignin / Q000302:isolation & purification*; D057139:Nanofibers / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013818:Thermogravimetry; D014908:Triticum / Q000737:chemistry*; D014866:Waste Products / Q000032:analysis*; D014961:X-Ray Diffraction
chemical_list: D014866:Waste Products; C036909:lignocellulose; D008031:Lignin
keywords: Characterization; Kraft; Lignocellulose nanofiber; Organosolv; Soda; Wheat straw