Preparation Of Supported Amorphous Catalyst And Its Catalytic Performance In Hydrodeoxygenation

With the petroleum resources shortage, price rising steadily and people payingattention to environmental problem increasingly, effective usage of fossil resources anddeveloping renewable resources has become a widely concerned research project. Biomassfuel is an ideal substitute because of the compounds containing a few nitrogen and sulfurelements. However, the biological oil is generated by biomass pyrolysis, which contains alot of oxygen-containing compounds such as acid, aldehyde, ketone, phenol and furan. Itleads to the low combustion heat and volatility, poor stability, high viscosity and strongcorrosive of the biological oil. Some biological oil can’t be directly used as high gradesources of energy due to the high oxygen content （up to50%）. Thus the high efficiencyand relatively inexpensive catalyst is necessary in order to refine the raw biological oil byhydrodeoxygenation. As a kind of new environmental friendly catalyst, amorphouscatalysts are widely used in hydrogenation reaction. Because they possess relatively highactivity and selectivity for hydrogenation reaction and other unique properties such asshort range order, long range disorder and high degree of unsaturation. However, theamorphous catalysts are invalid in some complicated environment due to the low thermalstability. Thus it is an important research direction for hydrodeoxygenation reaction byamorphous catalyst to improving the thermal stability and chemical stability andpreventing crystallization and loss active component of catalyst. Selection and preparationof functional supporter is an effective way to preventing crystallization of catalyst in theprocess of using.In this paper, Ni-Mo-B/SiO₂amorphous catalysts were prepared by using immersionmethod and deposition method with reducing agent （NaBH or KBH）, active component ofcatalyst such as La（NO₃）₃, Ni（NO₃）₂,（NH4）6Mo7O₂4and supporter such as SiO₂or Al₂O₃.The resulting catalysts were characterized by BET, SEM, EDX, XRD and XPS.Hydrodeoxygenation （HDO） properties of the catalysts were tested using phenol as themodel compound. Our results show that the catalyst exhibit large specific surface area,high thermal stability and excellent HDO properties during the reaction.The conversion ofphenol reaches100%very quickly and the selectivity of deoxygenation reaches up to96.53%at518K and4.0MPa. The atomic ratio of Ni/Mo had little effect on the activitybut reaction temperature deeply affects the selectivity of deoxygenation of the catalyst.For instance, the selectivity of deoxygenation is5%,45.39%, and96.53%at488K,508K,and518K, respectively.