Among the three natural macromolecules that constitute the biomass like straws and stalks

only lignin has the mole ratio of C

H

O (1∶1∙3∶0∙3)closed to that of crude petroleum (1∶1∙6∶0∙05).In this paper

rice straw was pretreated by weak acid and cellulase

92∙5% hemicellulose and72% cellulose were removed.And the sample that contained36% lignin was further reformed at low temperature (320℃

10MPa) to obtained gasoline and diesel oil fractions

that is

"bio-petroleum" .Compared with the oil obtained from rice straw

the relative content of long chain hydrocarbons were increased greatly(32∙5%)

while the relative content of the oxygenous compounds were decreased.So

the components of the oil were concentrated on the benzene and phenolic compounds

which was favor for further separation to obtain gasoline and diesel oil products with high value.