PROCESSING OF NON PURIFIED ETHANOL FROM A GLUCOSE FERMENTATION PROCESS FOR SOLID OXIDE FUEL CELL APPLICATION

摘要

In order to use ethanol as a fuel in a fuel cell, it must be processed into a form useable directly or indirectly by the fuel cell. We have conducted studies aimed at the catalytic processing of non-purified ethanol (i.e. filtered but not distilled product of a glucose fermentation process) to produce a direct fuel stream for a solid oxide fuel cell (SOFC) for stationary electric power generation. These studies involve catalyst design for reforming of ethanol as well as determining the optimum operating conditions (i.e. temperature, ethanol space velocity, water content and oxygen ratio) for maximum hydrogen selectivity and minimum energy requirement for the reforming reaction. This work also involved a thorough characterization of the catalysts. Initial results indicate that, if ethanol obtained from a fermentation process is used to produce H_2 by steam reforming, there are advantages in not purifying or removing the water present in the ethanol. Firstly, the water present increases the H_2 selectivity of the process, and secondly, the cost for ethanol purification is eliminated. Furthermore, with Ni/Al_2O_3 as the reforming catalyst, the overall process has better efficiency since the other organic components of non-purified ethanol are also steam reformed to produce additional H_2 and CO, both of which are used as direct fuels for the solid oxide fuel cell.