ABSTRACT
This chapter presents progress on lignocellulosic liquefaction under milder treating conditions, that is, at a temperature of 240–270°C without catalyst, or at a temperature of 80–150°C with an acidic catalyst. The liquefaction or dissolution of chemically modified wood has been developed, and the liquefaction of untreated wood has also been found to be possible. After the discovery of the phenomena of these wood liquefactions, various trials have been done to, increase the biomass concentration in the liquefaction mixture, obtain the true liquefaction degree in relation to the soluble properties of liquified biomass in organic solvents, and understand the mechanism of the liquefaction. Applications of these wood liquefactions have also been developed in the preparations of adhesives, moldings and foams. Chemically modified woods have been found to liquify and dissolve in neutral aqueous solvents, organic solvents, or organic solutions, depending on the characteristics of the modified wood, so far, three methods have been found for chemically modified wood liquefaction.
