| Biomass is rich and friendly environmentally renewable resource, which can be converted to hydrogen, high-quality liquid fuels and high value-added chemicals. As an alternative of fossil resources such as petroleum, coal and natural gas, the application of renewable biomass resource is receiving great attention globally. However, there are still remained many problems especially of conversion techniques and energy efficiency to make use of a wide variety of biomass types as a renewable energy source. The main content of present thesis was focused on the items as follows.(1). Efficient electrochemical catalytic reforming of bio-oil to produce hydrogenHigh efficient production of hydrogen from steam reforming of bio-oil was performed on the self-made NiCuZn/Al2O3 catalyst. A recently developed electrochemical catalytic reforming method was also applied. The effects of the reforming conditions, including temperatures, current, S/C etc., on the carbon conversion, hydrogen yield and products distribution were investigated. Results showed that the carbon conversion and hydrogen yield were both remarkably enhanced by the current. The maximum carbon conversion is 98.9% nd hydrogen yield is 93.2% n our investigated conditions. Hydrogen is a major product (-69 vol%) together with by-products of CO2 (-26 vol%) as well as very low content of CO (-5 vol%) and a trace amount of CH4.To make clear the mechanism of the electrochemical catalytic steam reforming, we studied the decomposition of model compounds (e.g., ethanol) experiments at low-pressure. Faraday-plate experiments were also performed to investigated the temperature and current effect on the emission current of the Ni-Cr wire. The alteration of the catalyst in the bio-oil reforming process were investigated viaXRD,XPS,BET and TGA measurements.(2). Alkali-promoted CuCoMn catalysts for mixed alcohols synthesis from bio-gasification syngas.A series of alkali-promoted CuCoMn catalysts were applied for synthesis of low carbon mixed alcohols from bio-gasification syngas. The variety and content of alkali influence the catalysts performances in many ways. The 3% mole fraction) Na promoted catalyst showed the best performance for higher alcohols synthesis. Some important reaction conditions including temperature, pressure, gas hourly space velocity were investigated. The carbon conversion significantly increases with rising temperature below 300℃, but the alcohols selectivity has an opposite trend. Higher pressure is beneficial to the higher alcohol synthesis. Increasing GHSV reduces carbon conversion, but enhances the yield of higher alcohols. The maximum higher alcohols yield derived from bio-syngas is 304.6 g·kg-1·h-1 with the C2+(i-C6 higher alcohols) alcohols of 64.4%(w, mass fraction) under the tested conditions. Both of the alcohols and hydrocarbons distributions are consistent with the Anderson-Schulz-Flory plots. Adding Na to CuCoMn catalysts favor to increase the selectivity of higher alcohols and promotes the dispersion of the active elements of copper and cobalt.(3). Methanol synthesis on dual-reactor from CO2-rich bio-oil reforming syngas.A dual-bed reactor, assembled with the on-line syngas conditioning and methanol synthesis, was successfully applied for high efficient conversion of CO-rich bio-oil derived syngas to bio-methanol. In the forepart catalyst bed reactor, the catalytic conversion can effectively adjust the crude CO2-rich syngas into the CO-containing bio-syngas. After the on-line syngas conditioning at 450℃CO2/CO ratio in the bio-syngas significantly decreased from 6.3 to 1.2. In the rearward catalyst bed reactor, the conversion of the conditioned bio-syngas to methanol shows the maximum yield about 1.21 kg MeOH (kgcatalyst·h)-1 with a methanol selectivity of 97.9%at 260℃and 50 atm using conventional CuZnAl catalyst. The influences of temperature, pressure and space velocity on the bio-methanol synthesis were also investigated in detail. Potentially, present bio-methanol synthesis may be one promising route to produce the bio-methanol from bio-oil.
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