LignoAnalyse 2: Step two of Lignin Analytical Cluster Directed Towards the Standardisation of Materials and Procedures Used During Lignin Processing

The aim of the project is the production and characterisation of fractionated lignin by nonaqueous titration, NMR spectrosopy, MALDI TOF MS, particle size distribution and zetapotential. The lignins can be used as reference material.

Fiche signalétique

  • Département HESB | Architecture, bois et génie civil
  • Pôle de recherche Matériaux et la technologie du bois
  • Champ de recherche Technologie des adhésifs et chimie des polymères
  • Organisme de financement COST
  • Durée 20.11.2006 - 23.01.2009
  • Responsable du projet Urs von Arx
  • Direction du projet Urs von Arx
  • Équipe du projet Ingo Mayer
    Aline Maillard
  • Partenaires - secteur privé PS Prozesstechnik GmbH
  • Partenaires - établissements de recherche, y c. BFH EPFL
    International Lignin Institute
  • Mots-clés Lignin, nonaqueous titration, NMR, MALDI MS, particle size distribution, zetapotential.

Contexte initial

Membrane separated lignins are characterized by the following already standardised methods: nonaqueous titration, 13C and 31P NMR spectroscopy, MALDI TOF MS. With 31P NMR spectroscopy aliphatic-OH, condensed phenolic-OH, syringyl-OH, guaiacyl-OH, p-hydroxyl-OH and carboxylic groups are parallel ascertainable. New protocols for the determination of the particle size distribution and the zetapotential of lignin particles in dispersions are developed.

But

Production of lignin fractions at laboratory and kg scale and characterisation of these fractions by nonaqueous titration, NMR spectroscopy, MALDI TOF MS, particle size distribution and zetapotential.

Compétences clés

Molecular mass determination by MALDI TOF MS; Determination of different OH groups and carboxyl groups in lignin with nonaqueous titration and NMR spectroscopy; Determination of the particle size distribution and the zetapotential.

Résultat

The molecular mass distribution of the fractionated lignins found by MALDI TOF MS is between 500 Da and 5500 Da with maxima at 1299 Da, 2100 Da and 2800 Da. The content of the different OH groups and the carboxyl groups of the fractionated lignins were determined by standardised nonaqueous titration and NMR methods. The particle size distributions of the fractionated lignins are between 240 nm and 400 nm , the zetapotentials of the same samples between -13 mV and -42 mV.

Perspectives

The total phenolic-OH content in lignins found by 31P NMR spectroscopy and by nonaqueous titration are notably different. The reason for this has not been explained so far and therefore further research is necessary.