Effective Hydrodeoxygenation Of Dibenzofuran

Catalytic hydrogenolysis is one of the most common molecular decomposition reactions. Aromatic ether structures are ubiquitous in biomass and coal resources. Catalytic hydrogenolysis of aromatic ether C-O bond is an efficient method to transform biomass and coal resources into chemical raw materials and fuel. Noble metal catalysts (Pt, Pd) have good catalytic activity, and non noble metal Ni catalyst has better selectivity of aromatic ether C-O hydrogenolysis. Based on the above factors, single metal catalysts Pt, Pd, Ni, Fe and bimetallic catalyst with different molar ratio NiPt, NiPd, FePt, FePd were prepared using a wet reduction method. TEM, XPS, XRD, UV-Vis and other characterization methods were used to characterize the catalysts. Dibenzofuran (DBF) was chosen as the hydrodeoxygenation (HDO) model compound for our research. The reaction activity and product selectivity of different solid metal catalysts in different reaction conditions were studied.Effective hydrodeoxygenation (HDO) of dibenzofuran (DBF) catalyzed by bimetallic Nig6Pti4catalyst in water was demonstrated at 200℃ and 1.2 MPa H2 pressure. The yield of hydrodeoxygenation products can be achieved up to 92% and the total conversion was of dibenzofuran (DBF) was up to 99%. The reaction pathway was also proposed as follows: hydrogenation of dibenzofuranand to hexahydrodibenzofuran and tetrahydrodibenzofuran, which react via 2-cyclohexylphenol and 2-phenylcyclohexanol to form double-ring hydrocarbons. And the major product was cyclohexylbenzene, and there were no C-C bond cleaving products detected. We proposed hydrogenation of the aromatic rings is the first step, following by the C-O ether bonds cleavage and the deoxygenation of cyclohexanol to produce O-free cyclohexylbenzene.Based on the TEM and XPS characterization, Ni/Pt bimetallic catalysts have smaller particle size than corresponding Ni single metal catalysts and Ni were enriched in the catalysts surface. The combination of the two single component exhibits prominent effects overcoming the limitations of a single component catalyst. It is interesting to see that Ni/Pt catalysts were effective in the hydrogenolysis deoxygenation of sp2 C-O bond here. The structural characteristics of the Ni/Pt bimetallic catalysts may be the reason of their high catalytic activity and selectivity than the same amount of single metal Ni or Pt catalyst.