Selective Catalytic Hydrogenation Of Furfural As Model Compound Of Bio-Oil

With the development of modern society,energy-efficient and high-quality fuels and chemicals are in great demand.The use of lignocellulosic biomass is one of the most attractive and promising options,as it is environmentally friendly and sustainable.Furfural is one of the top value-added chemicals derived from biomass and has recently been emphasized.In this dissertation,the main work is about the selective catalytic hydrogenation of furfural as model compound of bio-oil.Furfural was converted to target product by noble catalysts and non-noble catalysts.The reaction condictions was optimized,and mechanism of different kind of catalysts was also proposed.Additonally,other factors,including support,additive,and so on,were also investigated.The brief results are as follows:1.A series of Ni,Cu and bimetallic Cu-Ni catalysts with different metals loadings supported on CNTs were prepared by impregnation methods for liquid-phase hydrogenation of furfural to tetrahydrofurfuryl alcohol(THFA)using ethanol as a solvent.Various effects of reaction parameters such as,reaction temperature,reaction time,hydrogen pressure,different supports and different loading amount of Ni over both monometallic and bimetallic catalysts were fully studied.Among the catalysts investigated,10 wt%Ni/CNT and bimetallic Cu-Ni(Cu:10 wt%,Cu/Ni=1:1,molar ratio)catalysts showed high conversion of farfural and selectivity towards THFA.Bimetallic Cu-Ni catalysts exhibit the best catalytic performance of 100%conversion of furfural and up to 90.3%selectivity towards THFA at mild condition of 130?,40 bar hydrogen and 10 h reaction time.Cu-Ni bimetallic synergistic effect has been interpreted through XPS measurement and a possible hydrogen-transfer mechanism is proposed.The features of the CNTs supported catalysts were investigated via XRD,XPS,TEM,H2-TPR and the N2 adsorption-desorption isotherms.The Ni and bimetallic Cu-Ni catalysts prepared in this work is inexpensive and simple,which makes them a promising candidate for the conversion of furfural to THFA.2.Nano-Pt and Nano-Pd particles were introduced to modified multiwalled carbon nanotubes via co-impregnation method for hydrogenation of furfural in liquid phase using ethanol as a solvent.Different transition metal(Cr,Mn,Fe,Co,Ni)was used as promoters using Pt/CNT and Pd/CNT catalysts.Among the catalysts investigated,Pt-Fe/CNT(Pt:0.5 wt%)showed highest conversion and selectivity to furfuryl alcohol(yield of 87.4%),while Pd-Ni/CNT(Pd:0.5 wt%)catalysts exhibited the best catalytic performance(83.3%yield of tetrahydrofurfuryl alcohol)under the optimized conditions of 30 bar hydrogen and 5 h,at 100 and 130?,respectively.Moreover,different supports were used to support alloy compared to CNT support.Synergistic effect of bimetallic catalysts has been utilized to improve catalytic activity.Catalysts have shown stable activity and selectivity after 5 cycles using Pt-Fe/CNT and Pd-Ni/CNT catalysts.Bimetallic catalysts were characterized by various techniques such as XRD,TEM,HR-TEM,H2-TPR,NH3-TPD and XPS.