title: Use of a NICA-Donnan approach for analysis of proton binding to a lignocellulosic substrate extracted from wheat bran.
abstract: The acid-base properties of a lignocellulosic substrate extracted from wheat bran have been investigated. The lignocellulosic substrate was first studied by use of FTIR, XPS, and solid-state 13C NMR to characterize the surface-active groups. Major contributions arise from the presence of carboxylic and phenolic sites. The former are associated with long-chain fatty acids and the latter are constituent units of lignin. All ionizable sites were quantified by use of the Ca-acetate method and by potentiometric titrations in non-aqueous media. Results were compared with those from conductimetric titrations in water and in the presence of barium ions. Protometric titration curves for the lignocellulosic substrate were obtained at several ionic strengths. Data were also treated with the NICA-Donnan model to determine the intrinsic ionization parameters.
authors.affiliation: GRECI (Groupe de Recherche en Chimie Inorganique), Université de Reims Champagne-Ardenne, BP 1039, 51687 Reims Cedex 2, France.
authors.forename: J
authors.initials: J
authors.lastname: Bouanda
authors.forename: L
authors.initials: L
authors.lastname: Dupont
authors.forename: J
authors.initials: J
authors.lastname: Dumonceau
authors.forename: M
authors.initials: M
authors.lastname: Aplincourt
mesh_terms: D002482:Cellulose / Q000737:chemistry* / Q000302:isolation & purification; D004043:Dietary Fiber / Q000032:analysis*; D004563:Electrochemistry; D007477:Ions; D008031:Lignin / Q000737:chemistry* / Q000302:isolation & purification; D009682:Magnetic Resonance Spectroscopy; D011522:Protons
chemical_list: D004043:Dietary Fiber; D007477:Ions; D011522:Protons; C036909:lignocellulose; D002482:Cellulose; D008031:Lignin