Abstract
•The decomposition of lignocellulose is studied by in situ and ex situ techniques.•Three fractions, solid, liquid and gas are quantified and characterized.•The degradation temperature is lowered by 100°C in the presence of H3PW12O40.•At 300°C with H3PW12O40, the amount of liquid collected reaches 30wt.%.•Traces of furfural was observed from pure wood, with H3PW12O40 it reaches 2wt.%.
Transformation of lignocellulosic biomass to biofuels involves multiple processes, in which thermal decomposition, hydrotreatment are the most central steps. Current work focuses on the impact of several solid acids and Keggin-type heteropolyacids on the decomposition temperature (Td) of pine wood and the characterization of the resulted products. It has been observed that a mechanical mixture of solid acids with pine wood has no influence on Td, while the use of heteropolyacids lower the Td by 100°C. Moreover, the treatment of biomass with a catalytic amount of H3PW12O40 leads to formation of three fractions: solid, liquid and gas, which have been investigated by elemental analysis, TGA, FTIR, GC–MS and NMR. The use of heteropolyacid leads, at 300°C, to a selective transformation of more than 50wt.% of the holocellulose part of the lignocellulosic biomass. Moreover, 60wt.% of the catalyst H3PW12O40 are recovered.