Study Of Pyrolysis Kinetics Of Biomass Tar And Preparation Process Of Composite Nanofibers By Electrostatic Spinning

Biomass tar is a main by-product of biomass thermochemical conversion during biomass pyrolysis,which accounts for 5%-15% of the total energy.Biomass tar is hard to be naturally degraded or catalytically transformed because of its complex composition,furthermore,disposal of biomass tar has become a bottleneck in the industrialization of biomass gasification pyrolysis.Based on the physical and chemical properties,biomass tar can be used as a raw material for preparation of chemicals and carbon fiber materials,which provides a new route for its commercial utilization.To address the issues of high viscosity,complex components,and no-models for thermal decomposition and preparation process,studies of dynamic characteristics and preparation process of composite nanofibers from biomass tar and polyacrylonitrile by electrostatic spinning were conducted in this work.Findings will help to achieve the high value and clean utilization of biomass tar.The main contents and conclusions are as follows:(1)In view of the complex composition of two representative biomass tars(corn stalk tar and bamboo tar),and lacks of kinetic model for explanation of their thermal decomposition process,investigations on the components and thermal properties of biomass tar were carried out.(2)Spinning solutions with different raw material ratios had different apparent viscosities.The viscosity of the solution largely affects the diameter and continuity during the process of electrostatic spinning jet fibers.In this work,polyacrylonitrile(PAN)and biomass tar were adopted as matrix materials,and N,N-dimethylformamide(DMF)was used as a solvent to prepare Tar/PAN/DMF spinning solutions with different ratios.(3)Three factors and three levels orthogonal experiments were designed with three process parameters of biomass tar addition,spinning voltage and spinning distance to prepare Tar/PAN nanofibers with different diameters and morphologies,and their structures and properties were characterized.(4)Porous carbon fibers PAN-CNF and 30 Tar/PAN-CNF were prepared by pre stabilization carbonization method using the above-mentioned Tar/PAN electrospun nanofibers as precursors.Their structures,morphology and specific surface area were characterized,and their electrochemical properties were further studied.