Application of catalytic ozone chemistry for improving biodiesel product performance.

Ozonolysis of methyl soyate (biodiesel) was conducted in the presence of methanol, dichloromethane (solvent), and triethylamine (catalyst) at -75 degrees C. Structural analysis, including FTIR, GC, and GC-MS, showed that the total amount of double bonds in the mixture was reduced by more than 90% after 2 h of ozonolysis. All of the esters predicted by this novel application of ozone reaction chemistry were successfully produced. Other major components were identified by GC-MS. Thermogravimetric analysis showed a dramatic decrease in the onset volatilization temperature from 135 to 73 degrees C, making ozonated biodiesel fuel comparable to diesel fuel (76 degrees C). Differential scanning calorimetric studies showed that the cooling curves for both methyl soyate and ozonated methyl soyate displayed two exothermic regions. The onset freezing temperature of ozonated methyl soyate in the "colder" region was significantly reduced from -63 to -86 degrees C. Furthermore, the degree of crystallinity in the "hotter" region was also reduced.