Wild mustard (Brassica juncea L.) oil is evaluated as a feedstock for biodiesel production. Biodiesel was obtained in 94 wt.% yield by a standard transesterification procedure with methanol and sodium methoxide catalyst. Wild mustard oil had a high content of erucic (13(Z)-docosenoic; 45.7 wt.%) acid, with linoleic (9(Z), 12(Z)-octadecadienoic; 14.2 wt.%) and linolenic (9(Z), 12(Z),15(Z)-octadecatrienoic; 13.0 wt.%) acids comprising most of the remaining fatty acid profile. The cetane number, kinematic viscosity, and oxidative stability (Rancimat method) of the methyl esters was 61.1, 5.33 mm 2 s -1 (40°C) and 4.8 h (110°C), respectively. The cloud, pour and cold filter plugging points were 4, -21 and -3°C, respectively. Other properties such as acid value, lubricity, free and total glycerol content, iodine value, Gardner color, specific gravity, as well as sulfur and phosphorous contents were also determined and are discussed in light of biodiesel standards ASTM D6751 and EN 14214. Also reported are the properties and composition of wild mustard oil, along with identification of wild mustard collected in Brazil as Brassica juncea L. (2n = 36) as opposed to the currently accepted Sinapis arvensis L. (2n = 18) classification. In summary, wild mustard oil appears to be an acceptable feedstock for biodiesel production.

We report a facile Ru-catalyzed route to alkenes from unsaturated fatty acids (alkenoic fatty acids) via readily accessible catalyst precursors, [Ru­(CO)­2RCO2] n and Ru3(CO)12. The catalyst apparently functions in a tandem mode by dynamically isomerizing the positions of double bonds in an aliphatic chain and, subsequently, decarboxylating specific isomers with lower activation barriers. Substrates capable of tandem isomerization-decarboxylation processes (oleic acid, undecylenic acid) are readily converted to mixtures of alkenes. A catalytic cycle is proposed that relies on isomerization positioning double bonds proximate to the acid function to enable facile decarboxylation. To elucidate the proposed mechanistic pathway, substrates that do not undergo decarboxylation under these catalytic conditions (methyl oleate) are compared with those that cannot isomerize the position of unsaturation (cinnamic acid). Both were shown to be operational under these catalytic reaction conditions. Another illustrative comparison shows that the saturated octadecanoic acid is 28 times less reactive than the unsaturated counterpart when reacted using this precatalyst.