(596f) Experimental Determination of the Structural Evolution of Biomass Particles during Gasification

Gasification has been identified as an energy-efficient, environmentally-friendly and economically-feasible technology to partially oxidize biomass into a gaseous mixture of syngas consisting of H₂, CO, CH₄ and CO₂.  High-quality syngas can be further used to catalytically synthesize liquid fuels and produce hydrogen. Biomass gasification involves complicated structural evolution of solid biomass particles. During gasification, the physicochemical structure of biomass particle changes significantly when the volatiles are released. The change of the porous structure of biomass particles during gasification is critical in determining the mass transport of volatile species, and the physical properties of the particle. This research is to measure the structural evolution of biomass particles during gasification. A specifically designed tubular reactor and a thermogravimeter (TGA) are used to prepare biomass samples pyrolyzed or gasified at different temperatures. The porous structure, morphology, and structural evolution of biomass particle are analyzed by a surface area/pore analyzer, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction analysis (XRD), Infrared (IR) and Raman spectroscopy. The porous structure of the biomass particles will be first studied by using N₂ adsorption at 75 K using a Micromeritics ASAP 2020 surface area and pore analyzer. The pore structure of the biomass particles including pore size and pore size distribution as well as surface area are determined by the Brunauer-Emmett-Teller (BET) equation. Direct observation of the porous structure is performed using a Carl Zeiss Auriga-BU FIB FESEM microscope and Carl Zeiss Libra 120 Plus TEM microscope. The results from XRD and Raman examination will reveal carbon structure evolution during the gasification process.