摘要: |
Faculty and students from five universities--the University of Kentucky, University of Pittsburgh, University of Utah, West Virginia University, and Auburn University--are collaborating in a research program to develop C1 chemistry processes to produce ultra-clean liquid transportation fuels and hydrogen, the zero-emissions transportation fuel of the future. The feedstocks contain one carbon atom per molecular unit. They include synthesis gas (syngas), a mixture of carbon monoxide and hydrogen produced by coal gasification or reforming of natural gas, methane, methanol, carbon dioxide, and carbon monoxide. An important objective is to develop C1 technology for the production of transportation fuel from domestically plentiful resources such as coal, coalbed methane, and natural gas. An Industrial Advisory Board with representatives from Chevron-Texaco, Eastman Chemical, Conoco-Phillips, Energy International, the Department of Defense, and Tier Associates provides guidance on the practicality of the research. The current report presents results obtained in this program in its third year, as briefly summarized below. (1) Nanoscale iron-based catalysts containing molybdenum, palladium, or nickel and supported on alumina have been developed that are very effective for the dehydrogenation of methane and ethane to produce pure hydrogen and carbon nanotubes, a potentially valuable byproduct. Some of the nanotube structures are being investigated as a safe storage medium for hydrogen. Dehydrogenation of higher hydrocarbons, including several liquids that are compatible with vehicular transportation under fuel cell power, is currently under investigation. (2) Operation of Fischer-Tropsch (FT) synthesis under supercritical fluid (SCF) solvent conditions increases liquid fuel yields and improves the selectivity of the process to produce desired products. (3) Small additions ({approx}1%) of organic probe molecules with carbon-carbon triple bonds to the FT reaction markedly shift the molecular weight distribution and increase the oxygenate content of the products. The goal is to develop better technology for producing cleaner burning diesel fuel and other fuels. (4) Several different types of catalyst are under investigation to develop better control of FT fuel product distributions. (5) C1 processes have been developed for producing ethylene and propylene, two high-value products, from methanol. Novel silicoaluminophosphate (SAPO) catalysts containing nickel and other metals are used. (6) Binary tungsten-cobalt carbide catalysts have been found to have excellent activities and lifetimes for reforming of methane into synthesis gas using carbon dioxide. This type of catalyst is being further investigated for synthesis gas reactions relevant to the goal of producing hydrogen from coal. |