Hemicelluloses obtaining from rapeseed cake residue generated in the biodiesel production process

The processing of rapeseed oil seeds for biodiesel production generates huge amounts of lignocellulosic cake residue mainly composed by cellulose, hemicelluloses and lignin. In this work, the valorisation of these components, especifically the majoritary fraction, hemicelluloses, was studied. Hemicelluloses were extracted, purified and characterized by different techniques (FTIR, 1H NMR, 13C NMR, and GPC). Autohydrolysis and acid hydrolysis processes were applied to obtain sugar monomers and oligomers. Glucose and xylose were the main simple sugars in the obtained hydrolysates, representing 22.7% and 40.2% of total sugars content in the autohydrolysis hydrolysates and 27.7% and 36.6% in the acid hydrolysates respectively. Arabinose, galactose and mannose were present in relatively minor quantities.