| A variety of novel alkyl nitrate compounds were synthesized from triglyceride based feedstocks for use as diesel fuel cetane improvers. The addition of the nitrate functionality to organic compounds results in materials that readily decompose at temperatures around 200°C as determined by differential scanning calorimetry. The products from the decomposition include NO2, NO, aldehydes, and alkoxy and alkyl radicals, which are believed to accelerate the ignition of the bulk fuel charge at typical fuel injection conditions. Furthermore, the nitrate derivatives of triglyceride-based materials are capable of improving other properties of the diesel fuel including detergency and lubricity.; Production of a nitrate ester requires introduction of an alcohol functionality to the base triglyceride. A number of reactions are capable of producing this hydroxyl functionality. Epoxidation of the olefin groups of soya methyl esters produced an intermediate that readily underwent ring-opening reactions with either water or methanol to yield internal hydroxyl groups. A one-step interesterification of the native triglyceride with a diol produced compounds with a terminal hydroxyl group. This glycolysis reaction was achieved through the discovery of the catalytic activity of CaCO3. Finally, commercial syntheses of non-ionic surfactants also produce materials with hydroxyl functionality. All of the nitrated derivatives of these hydroxyl-containing intermediates were found to be active ignition stimulants.; One family of nitrate products derived from DEG and tallow is currently in advanced development for eventual industrial production. This highly active cetane improver product is being developed with the intent to market it as a renewable alternative to the commercial cetane improvers, 2-ethylhexyl nitrate and di-tertiary-butyl peroxide. |
