The purpose of the present study is to explore the effect of rubidium (Rb) and caesium (Cs) carbonate solutions (1 M) on the hydroliquefaction of wood biomass (280 degreesC for 15 min) products in the presence and absence (thermal) of bases by using an autoclave. Oxygenated hydrocarbons were extracted from liquid and solid portions and analyzed individually. The oil products were analyzed using gas chromatograph with mass selective detector (GC-MS). Catalytic hydrothermal treatment (Rb and Cs carbonates) of wood biomass produced mainly phenolic compounds and benzenediol derivatives. In thermal case 4-methyl-phenol, 2-furan carboxaldehyde and 2-methoxy-phenol were major compounds. 2-Furan carboxaldehyde and 4-methyl-phenol were not observed in catalytic runs. The use of base catalysts hindered the formation of char and favored the formation of oil products. The volatility distribution of hydrocarbons (ether extract) was characterized by using C-NP gram and it showed that of hydrocarbons for all runs including thermal were distributed in the boiling point region of n-C-6 to n-C-17. (C) 2004 Elsevier Ltd. All rights reserved.