S. Pu et N. Shiraishi, LIQUEFACTION OF WOOD WITHOUT A CATALYST .4. EFFECT OF ADDITIVES, SUCHAS ACID, SALT, AND NEUTRAL ORGANIC-SOLVENT, Mokuzai Gakkaishi, 40(8), 1994, pp. 824-829
Wood can be liquefied in the presence of phenols by heating it at abou
t 250-degrees-C. Because the liquefied products were found to be acidi
c solutions, the formation of acid during the liquefaction and the eff
ects of acids on liquefaction have been investigated. Acids which are
formed during liquefaction were found to be weak acids like acetic aci
d. The effect of the addition of neutral organic solvents on liquefact
ion also has been investigated. No accelerating effect by the addition
of acetic acid could be seen at a 7/3 wood/phenol ratio, whereas the
acid addition effect appeared when large amounts of formic acid, which
has a one order greater acidity than acetic acid, were used. Alkali o
r alkaline salt, which can neutralize the formed acid retards the reac
tion, although no effect of a neutral salt addition exists. Neutral or
ganic solvents miscible with the liquefied wood, retard the conversion
, whereas no obvious effect can be observed by the addition of immisci
ble solvents, for example, hexane.