Disordered components of lignocelluloses: characterization by infrared spectroscopy associated to the dynamics of isotopic exchange

Abstract

The woody, non-edible fraction of plants, the so-called lignocellulose, is a vast renewable resource that is nonetheless underexploited. Lignocelluloses have ordered - the cellulose nanocrystals - as well as disordered components, the latter made of hemicelluloses, lignin e fractions of cellulose. The supramolecular arrangements of the disordered components are poorly understood. This project will investigate these disordered components employing a new analytical technique, whose development is an essential element of the project. The new analytical technique will use (i) infrared vibrational spectroscopy, with (ii) polarization of the radiation and (iii) isotopic exchange in deuterated water. The combination of these three elements is a well-established approach, to which the project will add a fourth dimension that is (iv) the dynamics of the isotopic exchange. The additional dimension is expected to resolve spectral components, thus helping to understand material properties. The results obtained with the new technique will be contextualized from comparisons within a wide spectrum of samples that will be also characterized by the other techniques available in our group. Once developed, the new technique will be applied to lignocelluloses of major economical relevance, such as sugarcane bagasse and eucalyptus wood, in raw states as well as after processing. The success of the project will deliver a spectroscopy technique with extraordinary informative power, applicable to a large spectrum of plant biomasses. (AU)