Lignin Carbohydrate Complexes structure preserved throughout downstream processes for their valorization after recovery from industrial process water

Abstract

Firstly studied and pointed out because of their major role in wood recalcitrance to delignification, LCCs are gradually raising interest about their own valorization thanks to their various interesting properties. Considering their future industrial production, this work is focused on evaluating the impact of different downstream processes (DSP) on their structure including moist heat sterilization, simple effect evaporation and spray-drying. LCCs were recovered from the mill water of a thermomechanical plant by successive membrane filtration steps. Samples were taken after the different DSP and compared to a freeze-dried control. Global and structural characterizations given by elemental analysis, acid hydrolysis, pyrolysis coupled to gas-chromatography, SEC, ¹³C and 2D-HSQC NMR showed that the LCCs structure is well preserved during all of these DSP. This paper demonstrates the feasibility of producing high quality industrial LCC grade for commercialization in integrated biorefineries.

Keywords: Characterization; Lignin Carbohydrate Complexes; Thermal treatment.