Study On The Catalytic Hydrodeoxygenation Of Phenol With NiCu/SiO₂ And The Influence Of The Introduction Of Aliphatic Acid

The renewable energy resources are of great importance for the society because of the depletion of fossil fuel reserves and environmental apprehensions around the world.Biomass is one of the cheapest resource available.Biomass can be converted to bio-oil through pyrolysis,and bio-oil can be transferred to liquid fuel by further catalytic upgraded.One of the most promising strategies for the production of liquid fuels is the catalytic hydrodeoxygenation（HDO）of lignin-derived compounds.In this study,a series of bifunctional Ni-Cu/Si O₂ catalysts with nickel phyllosilicate（Ni-PS）have been synthesized by the process of evaporation of ammonia（AE）.The influences of Ni and Cu ratio,and the reduction temperature on the HDO activity of catalysts were studied with phenol as the model compound.Different characterization methods including X-ray powder diffraction（XRD）,Fourier transform infrared spectroscopy（FT-IR）and Transmission Electron Microscope（TEM）were also taken to explain the influence on the HDO activity of the catalysts.The results confirmed that compared with 700 ℃,the lower reduction temperature 400 ℃ left more phyllosilicate in the catalyst and provided acid sites for the catalysts,which was helpful to the deoxygenation of phenol and the highest selectivity of cyclohexane was 84%.And the formation of Ni-Cu alloy of the bifunctional Ni-Cu/Si O₂ catalyst was also responsible for the satisfactory HDO activity and Ni₅Cu₁/Si O₂showed the best performance in the hydrodeoxygenation of phenol.Lauric acid was selected as the model of triglycerides and its influence on the HDO of phenol was also studied in this research.The maximum selectivity of cyclohexane was 79.4%and appeared when 0.2 g of lauric acid was added.The Results indicated that the amount of lauric acid showed an obvious influence on the deoxygenation of phenol.Relatively less amount of lauric acid facilitated the deoxygenation process however too much introduction suppressed the conversion of cyclohexanol to cyclohexane.