Research About The Steam Reforming Of Model Compound Of Bio-oil Light Component For Hydrogen Production

Biomass as a renewable carbon resource, through fast pyrolysis can obtain biomass oil and energy-oriented use, is an important direction of alleviate energy crisis, environmental pollution and biomass utilization. But biomass oil has the characteristics of strong acidity and high water content, we can get high boiling point fractions (heavy components) without water or acid as well as low boiling point fractions (light component) with rich water and a small amount of acid, aldehyde, ketone, alcohol, phenol and other oxygen-containing organic compounds by distillation and grading treatment. The heavy components via further catalytic upgrading can gain liquid fuel and light components of oxygen-containing organic compounds can through steam reforming for hydrogen production.The key to bio-oil light components reforming for hydrogen production is the effective stability of catalyst and the economy of reaction conditions. Therefore, this thesis use acetic acid as the model compound of bio-oil light component, using fixed bed flow dynamic atmospheric reaction technology, carry out a research that hydrogen production by steam reforming of bio-oil light component over nickel-based catalysts, obtained the following main research results:The supports of MgO, γ-Al2O3, ZrO2and CeO2loaded nickel catalysts were prepared by the impregnation method, we examined their reaction performance in the acetic acid steam reforming at low temperature. The conversion of acetic acid close to100%, large hydrogen production quantity and good stability over Ni/CeO2catalyst at350℃low temperature and atmospheric pressure. Characterization results show that the strong interaction of Ni/MgO and Ni/γ-Al2O3catalysts, due to low metal Ni can be used, not favour of reforming reaction. Ni/CeO2catalyst due to the weak interaction between Ni and CeO2, easy to reduction, and more metal Ni, has the high ability of reforming hydrogen production. Therefore, the extent of interaction between the supports and nickel is the main affect factor of catalysts in steam reforming.Use cerium zirconium composite oxide as a support and prepared by coprecipitation method, investigated the Ni/CeO2-ZrO2catalyst with different Ce/Zr ratio, we found that the performance of Ni/CeO2-ZrO2catalyst is better than Ni/CeO2catalyst for hydrogen production by steam reforming of acetic acid. Different Ce/Zr ratio mainly affects the CexZr1-xO2solid solution structure, impacts the reduction degree and particle size of NiO species. The research of Ni amount and calcined temperature further shows that the catalytic performance of Ni/CeO2-ZrO2catalyst has a corresponding relationship with the number of reducible nickel species and particle size.By changing the reduction temperature, reaction temperature and the content of acetic acid, investigated the property of Ni/CeO2-ZrO2catalyst for steam reforming of acetic acid. Results show that there are two ways of acetic acid steam reforming for hydrogen production in this catalyst system. One type, acetic acid can be directly steam reforming on the metal Ni; another, by ketonization formed acetone on the support, then reforming on nearby Ni components.