VTT has first-class analytical facilities for the characterisation of lignin structure and its material properties, e.g. lignin functionalities, detailed chemical substructures and inter-unit linkages, substitution patterns of aromatic subunits, molar mass distributions, and thermal properties.
Detailed lignin characterisation is a prerequisite for the elucidation and adjustment of structure-property correlations when developing new lignin based products, in order to bring added value to modern biorefineries. Knowledge of the effects of process conditions on lignin structure is also essential for the development of novel biomass deconstruction methods, and for optimisation of more traditional pulping and bleaching processes towards better resource and cost efficiency. Furthermore, lignin quality can be improved by various fractionation and purification methods available at VTT.
VTT has continuous collaboration with the pulping industry as well as biofuel and biochemical producers that are interested in lignin-containing process streams as raw material. By characterisation of the lignin quality in respect of purity and structure, significantly better means for lignin valorisation and process optimisation can be obtained.
Long tradition in lignin chemistry
VTT has a long tradition in lignin chemistry, originating from the development of delignification processes for the pulping industry, and also versatile pretreatment methods for biorefinery in general. Presently, there is a strong focus on lignin valorisation, utilising the aromatic nature of lignin in order to replace synthetic phenols in novel biobased products. Detailed chemical characterisation and knowledge of lignin chemistry are key elements in all these.
First-class analytical facilities
VTT has first-class analytical facilities with all the required modern analytical tools for a detailed characterisation of lignin structure and its material properties.
- Lignin functionalities can be determined by 31P NMR spectroscopy
- Detailed chemical substructures and inter-unit linkages can be identified and quantified by modern 2D NMR spectroscopic techniques
- Substitution patterns of aromatic subunits can be revealed both by NMR and pyrolysis GC/MS. The latter is also applicable to insoluble samples, and can be used in lignin characterisation directly from biomass without isolation of the lignin
- Molar mass distributions can be determined by SEC
- Thermal properties (Tg, Tdeg) can be analysed by DSC and TGA
- Elemental analyses are also available
Lignin separation technologies include e.g. membrane filtration, which can be carried out from laboratory to bench and pilot-scale.