(737c) Alkene Metathesis of Camelina FAME with Supercritical Ethylene

Akene metathesis of unsaturated FAME with ethylene is a powerful synthesis reactor to produce terminal alkenes which can be used for synthesis of polymers and other valuable compounds.  Although commercial metathesis catalysts have been proven to be efficient in converting pure FAME, this process has not been used effectively in a mixture of methyle esters like biodiesel.  Moreover, there has been no study in the literature that has used supercritical ehtylene in alkene metathesis.  We anticipate to minimize mass transfer limitations with the use of supercritical ethylene during metathesis with FAME.

In this study FAME derived from camelina oil, which contains as much as 90S% unsaturated components, was allowed to react with supercritical ethylene at room temperature in the presence of Grubb's catalyst.  A high pressure syringe pump is used to deliver 750 psi of ethylene and the reaction is performed in a 500 mL high pressure and high temperature reactor fro 4 hours.  Different commercial first and second generation Grubbs catalysts were tested.  Depending on the nature of the catalyst, self metathesis of FAME, isomerization and cyclization were observed as well at varying degrees as evidenced by GC/MS analyses.  Percent conversion of unsaturated FAME as high as 87% was observed.