ABSTRACT
Increased environmental awareness has promoted the development of alternate forms of chemicals, materials, and energy to traditional fossil sources, which produce approximately 73% of greenhouse gas emissions, particularly CO2 (Lokhorst and Wildenborg, 2005). For example, ethanol has attracted attention worldwide for use as an alternative automotive fuel. Unlike fossil fuels, ethanol is a renewable energy source which can be produced by fermentation of sugars. It is widely used as a partial gasoline replacement in Brazil and the United States. During combustion, ethanol acts as an oxidizing agent, and ethanol/gasoline blends therefore produce fewer harmful emissions, such as carbon monoxide (CO) and nitrogen oxides (NOx), compared with gasoline (Takahashi et al., 2000; Mielenz, 2001).
