Organosolv extraction method

Over the last decades, infrared (IR) vibrational sprectroscopy has been well established as a useful tool for structure elucidation and quafity control in several industrial applications. Indeed, the development of Fourier transform (FT) IR and attenuated total reflectance (ATR) techniques have also evolved allowing rapad IR measurements of organosolvent extracts of plant tissues, edible oils, and essential oils, for example (Damm et al., 2005 Lai et al., 1994 Schulz Baranska, 2007). In consequence of the strong dip>ole moment of water, IR spectroscopy applications have mostly focused on the analysis of dried or non-aqueous plant matrices and currently IR methods are widely used as a fast analytical technique for the authentication and detection of adulteration of vegetable oils. 

A group of methods to obtain lignin are known as organosolv procedures. They consist of an extraction of wood sawdust with an alcohol (such as ethanol) and some acid (5% HCI) in stronger conditions (boiling under reflux) followed by the reprecipitation of lignin from the extract. 

A variety of methods exits to extract native (nonmodified) lignin totally or partially from lig-nocellulose biomass. These methods use organic solvents like methanol or ethanol (Organosolv process [43]) or even pure water (steam explosion process, Aquasolv process [41,44-47]), but... 

Several methods for the fractionation of hemicellulose from lignocellulose have been described in the literature. These include physical methods such as steam treatment (7-73), and chemical methods such as for exanq>le organosolv processes (d, 14, 75). In addition, microwave irradiation of lignocellulose in the presence of water has been investigated for the purpose of enzymatic saccharification and ethanol production (7d-7S) and within our project for the extraction of hemicellulose (7). 

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