The Development Of Nickel Catalyst Of New Type And Its Application Research On Biomass Catalytic Gasification

At present, energy industry and environmental field in China are both confronted with challenge. As a clean energy, biomass energy has been paid close attention to home and broad. The gas of heat value taken from biomass gasification or pyrolysis can be used as fuel or used for civilian power generation, which is one of the most promising research issues. However, tar in biomass gasification gas has great hazards on the follow-up equipment, so a large amount of research is focusing on tar removal and improving gas product. Biomass tar is of complex composition. The use of catalyst can effectively reduce the tar content, and improve the quality of gas. In a word, FCC is a great potential gasification technology of purification.Given the key problem of tar cracking in the biomass conversion technologies, the work was carried out as the following:(1) Nano-Fe2O3 powders and nano-La₂O₃ were prepared through homogeneous precipitation, respectively, and the conditions of preparation were investigated; then, a new type of composite supported catalyst--Ni-Fe-La/γ-Al₂O₃ was developed, and effects of calcination conditions on the particle size of catalytic active ingredient were analyzed. This supported catalyst which was coating with similar egg shell structure, had core ofγ-Al₂O₃, and shell of the composite nano-metal oxidation, which of a multi-layered three-dimensional structure, and large specific surface area. The XRD and SEM analysis both showed that Ni-Fe-La/γ-Al₂O₃ catalyst calcined at 400℃had the minimum size.(2) The catalytic performance of homemade Ni-Fe-La/γ-Al₂O₃ catalyst in fixed-bed reactor was advanced by contrast with other catalysts, i.e, olivine, dolomite, Ni/γ-Al₂O₃ and pyrolysis (no catalyst) using sawdust and scrap wire skin as raw materials, respectively. The results indicated that gas production/gas production rate from pyrolysed with catalysts improved more than it from with no catalyst; more combustible gas, especially H₂ and CO were produced, and content of tar was the smallest. The catalytic performace listed as follows: Ni-Fe-La/γ-Al₂O₃ catalyst>Ni/γ-Al₂O₃ catalyst>dolomite>olivine. More tar and charcoal, and less gas generated from pyrolysing scrap wire skin, compared to pine sawdust pyrolysis.