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item Knothe, Gerhard - Gary

Submitted to: World Expo
Publication Type: Abstract Only
Publication Acceptance Date: 6/20/2000
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: The alternative diesel fuel termed "biodiesel" (usually methyl esters of veg. oils) regained considerable interest since the late 1970's due to the energy crises. However, the use of veg. oil-derived diesel fuels is nearly as old as the diesel engine. The inventor of the diesel engine, Rudolf Diesel, discussed the fuel use of veg. oils under surprisingly modern aspects. From the 1920's through about 1945, numerous reports discuss veg. oil-based diesel fuels. In 1980, veg. oil methyl esters were reported to solve the problem of high viscosity of neat veg. oils. Neat veg. oils can now be considered abandoned as alternative fuels. In the U.S., veg. oil-based diesel fuels were initially intended to provide farmers with a "do-it-yourself" fuel for times of high cost of conventional diesel fuel or another energy crisis. Driving forces such as increasingly stringent environmental regulations, energy security, and utilization of excess veg. oil have caused the use of veg. oil-based diesel fuels to expand significantly. These driving forces can override the higher cost of biodiesel in comparison to conventional diesel fuel. Neat biodiesel and B20, a 20:80 biodiesel/petrodiesel blend, are recognized as alternative fuels under Energy Policy Act criteria. A provisional biodiesel standard exists. Environmentally, biodiesel is significant because most exhaust emissions, with the exception of nitrogen oxides (NOx), are reduced in comparison to conventional diesel fuel. Thus, the reduction of NOx exhaust emissions is a major research challenge to biodiesel. Other significant research areas are the improvement of low-temperature properties, improvement of long-term storage stability and improved analytical methods.