During the pyrolysis of biomass which occurs in the absence of a solvent, it is known that the inorganic matter in the biomass enhance the initial rate of decomposition; however, they also accelerate the formation of char through radical recombinations (Aho et al., 2013 and Eom et al., 2012). However, research on the effect of inorganic matter on the hydro-/solvothermolysis of biomass is rarely performed. To investigate the effect of matter inorganic matter in EFB, a comparative study of raw EFB and washed EFB, in which the inorganic matter was removed, was carried out