Study On One-pot Conversion Of ?-pinene To Biomass High-density Fuel Catalyzed By Bifunctional Microporous Molecular Sieves

With the widespread use of fossil energy worldwide,especially as a transportation fuel,it has greatly increased the concentration of CO2 in the atmosphere.Governments and agencies of worldwide countries have proposed and planned a variety of solutions to reduce carbon dioxide emissions.Among these solutions,the development of renewable energy such as biofuels has the most prominent advantages.The green and sustainable natural biomass resources of turpentine are rich in the rigid polycyclic hydrocarbon structure of C10-C15,which provides the possibility and material basis for the preparation of biomass high energy density fuel(HEDF)with good performance to replace petroleum-based products,and has a good development prospect..Firstly,the catalytic performance of different types of acidic molecular sieves in the dimerization of ?-pinene,the main component of turpentine,was screened.It is found that H? molecular sieve has excellent catalytic activity,dimer selectivity,suitable shape selectivity properties and reuse stability,and the acidic catalytic activity of H? molecular sieve increases first and then weakens with the increase of Si O2/Al2O3.In addition,the effects of pretreatment conditions such as the calcination temperature and calcination time of H? molecular sieve on the dimerization of?-pinene were also studied.The SOT-H? molecular sieve with good catalytic activity in the dimerization reaction of ?-pinene was prepared by steam-assisted method(SAC)and seed-organic template method(SOT).The bifunctional catalyst with excellent acid catalytic performance and hydrogenation reduction performance was created by impregnation and loading coupling transition metal.According to this,biomass high energy density fuel was prepared by dimerization-hydrogenation “one-pot” reaction.The effects of the coupling reduction mode of transition metal nanoparticles and acidic support,the type and amount of supported metal on the acid catalytic ability and catalytic hydrogenation ability of the bifunctional catalyst were investigated.The process conditions for “one-pot” reaction were optimized under the preferred Ru/SOT-H?catalysis.In addition,pinane,which is also derived from turpentine resources,is used instead of toluene as the dispersion medium for the “one-pot” reaction.And under the optimized reaction operation process,the mixed liquid product obtained by the reaction does not require solvent evaporation and other operations.It can obtain excellent oil close to that of petroleum-based high density fuels.Thereby providing a clean and efficient new way for the development of turpentine biomass HEDF.In order to further improve the stability of the dual-functional catalyst,this paper also prepared Ru/FSOT-H? dual-functional catalyst with fish-in-pore structure by high-temperature dealumination.The study found that the trap structure formed by dealumination on the surface of the H? molecular sieve by high temperature treatment has a good stabilization effect on the metal nanoparticles,so that the dispersion stability of metal nanoparticles in the bifunctional catalyst has been greatly improved.This study also provides a practical new solution for the synthesis of HEDF from natural biomass resources.