Catalytic Furfural Preparation Of Renewable Fuels 2-Methylfuran And 6-Butyl Undecane

As the only chemical energy in renewable energy,the effective use of biomass was considered to be the key to solve the current energy shortage.The furfural derived from the second-generation biomass raw material lignocellulose has been widely used in recent years to catalyze the preparation of biomass liquid fuels due to its high reactivity brought by its structural characteristics.Among them,2-methylfuran,the product of direct catalytic hydrodeoxygenation of furfural,has better gasoline-like characteristics than bioethanol,and is a fair choice for gasoline substitutes.The 6-butylundecane prepared by the two-step catalytic reaction of furfural and 2-methylfuran through hydroxyalkylation/alkylation and hydrodeoxygenation can meet the performance requirements of aviation aircraft for high-quality fuel.Therefore,in this paper,by catalyzing the conversion of furfural,the biomass liquid fuels 2-methylfuran and 6-butylundecane were prepared respectively.1.A Mo-doped Ni-based catalyst Ni-Mo/ZrO₂ was prepared and used to catalyze furfural to prepare 2-methylfuran.Under the reaction conditions that the Ni content in the catalyst was 10%,the Mo:Ni molar ratio was 0.6:1,and the reaction conditions were180℃,6 h,and 3 MPa H₂,the yield of 2-methylfuran reached 93.9%.After the catalyst was used repeatedly for 5 times,the yield of 2-methylfuran still exceed 80%.The catalyst had excellent reaction performance.The structure characterization of the Ni-Mo/ZrO₂ catalyst found that the addition of Moand the Ni in the catalyst formed a MoNi₄ structure which avoided the adsorption of the furan ring in furfural on the Ni（111）crystal surface,thereby avoiding the hydrogenation of the furan ring.The surface of Moelement could adsorb a large amount of dissociated H and can also avoid the adsorption of furan ring on the surface of the catalyst.The strong acidic site brought about by the addition of Mocan promote the cleavage of the C-O bond that is the active site for removing the alcoholic hydroxyl group in the reaction intermediate furfuryl alcohol.These characteristics of the catalyst converge can create the high yield of 2-methylfuran.In addition,the catalytic reaction mechanism of furfural on Ni/ZrO₂ and Ni-Mo/ZrO₂ catalysts was also proposed.2.MoO₃-TiO₂ and Ni/Mo₂C catalysts were prepared separately and used to catalyze furfural and 2-methylfuran to prepare 6-butylundecane in two steps.The MoO₃-TiO₂ catalyst was used to catalyze the hydroxyalkylation/alkylation reaction of furfural and 2-methylfuran.It was found when the MoO₃ content in the catalyst was10%and the reaction condition of 60℃,6 h,mol ratio of furfural:2-methylfuran=2:2.05,the yield of HAA product reached 94.6%.The characterization of the MoO₃-TiO₂catalyst found that the combined effect of the L acid site in TiO₂ and the B acid site in MoO₃ was a key reason for the catalyst’s high catalytic activity.The Ni/Mo₂C catalyst used to catalyze the hydrodeoxygenation of HAA products also had excellent performance.Under the reaction conditions of 4%Ni in the catalyst and 240℃,10 h,5 MPa H₂,the yield of alkanes was 97.1%,The yield of 6-butylundecane reached 86.1%.The strong acid sites in the catalyst promoted ring opening,and Ni brought high hydrodeoxygenation activity,which resulted in a high yield of total alkanes.The high dispersion of Ni in the catalyst and the precious metal-like properties of Mo₂C together avoided the cleavage of the C-C bond in the catalytic reaction,which is the reason for the high yield of 6-butylundecane.In addition,the catalytic reaction mechanism of furfural and 2-methylfuran on MoO₃-TiO₂ catalyst was proposed.