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In order to utilize lignocellulosic biomass as a feedstock for bioethanol, ozone pretreatment was conducted on Japanese cedar sawdust and three other lignocellulosic wastes. Successful lignin degradation was accomplished by ozone pretreatment of the Japanese cedar sawdust and over 90% of polysaccharides were converted to monomeric sugars by enzymatic saccharification. This ozone pretreatment was also effective with other lignocellulosics, such as Hinoki cypress sawdust, lumber and board wastes. Ethanol production by simultaneous saccharification and fermentation of the ozone pretreated Japanese cedar sawdust was also successful. It was shown that ozone pretreatment increases enzymatic susceptibility and enables the production of ethanol from lignocellulosic biomass.

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Chlorine-free bleaching was carried out on kraft pulp from oil palm empty fruit bunches (EFB) with an oxygen (O 2 ) -acid (H 2 SO 4 ) -ozone (O 3 ) -hydrogen peroxide (H 2 O 2 ) bleaching sequence. The κ-number (= an indicator of lignin content) of the pulp was reduced considerably after these processes indicating that most of the lignin present in the pulp can be removed using this chlorine-free sequence. Handsheets of both bleached and unbleached EFB pulp were prepared and their paper properties were determined. Brightness, a measure of the whiteness of paper, was achieved to ca. 75% for the bleached EFB pulp, showing a possibility of achieving 80% of brightness by chlorine-free bleaching. Paper strengths as indicated by tensile, tear and burst indices as well as stretch did not show significant differences between before and after bleaching. It is notable that these results were obtained despite a large decrease in viscosity by the bleaching process. Moreover, the EFB bleached pulp showed comparable strengths to hardwood pulps, indicating that EFB has the potential as a raw material for chemical pulp production using chlorine-free bleaching sequences.