Nanoscale Mos < Sub > 2 < / Sub > And Hydrogenation Deoxidization Performance Research Of Preparation Of Catalyst

With the continuing depletion of the reserves of non-renewable petroleum and the worsening environment pollution, bio-oil, as a clean and renewable energy, has attracted much attention. However, the unpurified bio-oil contains many oxygenic compounds, leading to the high oxygen content of bio-crude(40wt%), which lead to some detrimental properties, such as low heating value, chemical instability and immiscibility with hydrocarbon fuels and so on. It is very necessary to selectively remove oxygen from the bio-oil via the hydrodeoxygenation(HDO) to improve the quality of the upgraded bio-oil. Furthermore, the key of HDO technology is developing catalysts with high activity and good stability. In this article, a series of unsupported MoS2and Ni(Co)-MoS2catalysts were prepared, and were characterized by means of BET, XRD, SEM and TEM. Their catalytic activities were tested with4-methylphenol as a model compound. The MoS2catalysts were successfully prepared by a mechanical activation method, in which MoO3and S was used as reactants, and the influence of annealing temperature on their structures and catalytic functions were also discussed. The results showed that the obtained MoS2nanosheets had short low stacking layers, the length and width were about100nm and10nm, respectively. Moreover, they were monodisperse and had high surface area(about83.6m2/g). When the preparation temperature was500℃, MoS2nanosheets possessed the highest catalytic activity, the conversion of4-methylphenol was58.2%. The hydrodeoxygenation of4-methylphenol mainly favored the hydrogenolysis route. As the preparation temperature of MoS2nanosheets increasing, the selectivity of hydrogenation pathway was enhanced gradually.The Ni(Co)-MoS2catalysts were successfully prepared by adding Ni(NO3)2·6H2O and Co(NO3)2·6H2O in ball milling process, and the influences of assistants (Ni and Co) on MoS2catalysts were investigated systematically, including their structures and catalytic functions. The results showed that the addition of Ni and Co would reduce the specific surface area slightly but improve their metal dispersion. The addition of Ni would promote the crystal growth of MoS2, and the facilitation would increase significantly with the increasing of the amount of Ni, However Co would suspend it at relatively low temperatures. Both of them enhanced the final activity of MoS2catalysts, while, the activities of them were both increased consistantly and reached the maximum value at600℃, then reduced sharply due to the formation of bulk segregations with the increasing of annealing temperatures. In addition, the activity of Ni-MoS2catalysts was decreased consistantly with the increasing of the amount of Ni and reached the maximum value when the molar ratio of Ni and Mo was1/4. Ni-MoS2catalysts favored the reaction route of hydrogenation(HYD) but Co-MoS2catalysts preferred the reaction route of direct-deoxygenation(DDO) in the HDO of4-methylphenol.