Study On The Preparation Of MOFs-based Catalysts And Selective Catalyzed Hydrogenation Of Furfural

Furfural,as an important biomass platform molecular compound,can produce a series of value-added chemicals through oxidative esterification,catalytic hydrogenation,aldol condensation and oxidative condensation.However,the key to high-value utilization of furfural is to design and develop highly active and selective catalyst.Metal-organic frameworks?MOFs?materials are organic-inorganic hybrid porous materials formed by self-assembly of organic ligands and metal ions or clusters through coordination bonds,which have both the rigidity of inorganic materials and the flexibility of organic materials.In recent years,MOFs materials have been widely studied in preparation of heterogeneous catalyst.This thesis aims to synthesize metal carbon material catalyst with high metal dispersion using MOFs as precursors to selective hydrogenate furfural to prepare value-added chemicals.Co/C was prepared by using sacrificial template-autoreduction method with ZIF-67 as precursor and then Co/C catalyst was modified by the impregnation method to obtain a Cu-Co/C.X-ray diffraction?XRD?,high-resolution transmission electron microscope?HRTEM?,scanning electron microscope-energy dispersive spectrometer?SEM-EDS?,X-ray photoelectron spectroscopy?XPS?,H₂-programmed temperature reduction?H₂-TPR?,vibration sample magnetometer?VSM?,Fourier transform infrared?FTIR?spectroscopy,specific surface area measuring instrument?BET?and other characterization methods have been to apply to study the structural characteristics of Co/C and Cu-Co/C.Furfural can be completely converted over Cu-Co/C with 97.4%furfuryl alcohol selectivity at 200^oC for 2.5 h.Cu/C was prepared by using sacrificial template-autoreduction method with Cu-MOFs as precursor.XRD,SEM,TEM,XPS,FTIR,H₂-TPR,thermal gravimetric?TG?analyzer,NH₃-programmed temperature oxidation?NH₃-TPD?and other characterizations show that the average particle size of Cu nanoparticles embedded on its surface was up to 80 nm,but Cu/C has also high metal dispersibility and stability due to the good metal dispersibility of Cu-MOFs.And 99.4%furfural conversion and100%furfuryl alcohol selectivity obtained at 150^oC for 2.5 h.Ni_0.09Zn/NC₆₀₀ and Co₂₀Zn/NC₆₀₀ were prepared by epitaxial method and impregnating Ni and Co with ZIF-8 as precursors using sacrificial template and supported self-reduction method.XRD,SEM,TEM,XPS,FTIR,H₂-TPR,NH₃-TPD,TG and laser ablation-plasma mass spectrometry?LA-ICPMS?show that Ni_0.09Zn/NC₆₀₀ has a spherical shape on the whole surface,and a large number of Ni₃ZnC_0.7 nanoparticles are uniformly inlaid on Ni_0.09Zn/NC₆₀₀ surface.Co₁₇Zn/NC₆₀₀is also spherical in shape as a whole,and the nanoparticles uniformly distributed on the surface are Co₃ZnC nanoparticles.Co₁₇Zn/NC₆₀₀ hydrogenated furfural with 100%furfural conversion and 100%furfuryl alcohol selectivity at 125^oC for 2.5 h.Over Ni_0.09Zn/NC₆₀₀,100%furfural conversion and 100%furfuryl alcohol selectivity are obtained at 170^oC for 2 h in isopropanol;100%furfural conversion and 86.4%tetrahydrofurfuryl alcohol selectivity are obtained at 150^oC for 1 h in water;100%levulinic acid conversion and 100%?-valerolactone selectivity are obtained at 65^oC for 1.25 h in water.Co₃ZnC and Ni₃ZnC_0.7 nanoparticles are the active components for hydrogenation of furfural in Co-Zn/NC and Ni-Zn/NC which were confirmed via hydrogenation of furfural over Co-Zn/NC and Ni-Zn/NC prepared by using a series of different Co or Ni loadings and different calcination temperatures.This thesis contains 63 Figures,17 Tables and 139 References.