Submitted to: Society of Tribologists and Lubrication Engineers
Publication Type: Abstract Only
Publication Acceptance Date: 12/15/2011
Publication Date: 5/6/2010
Citation: Knothe, G.H. 2010. Lubricity studies with biodiesel and related compounds [Extended abstract]. Society of Tribologists and Lubrication Engineers Annual Meeting & Expo. p. 129.
Technical Abstract: Biodiesel, the alkyl esters of vegetable oils or animal fats, possesses excellent lubricity. This feature has rendered biodiesel of special interest for blending with ultra-low sulfur diesel fuels with poor lubricity. However, some minor components, mainly free fatty acids and monoacylglycerols, of biodiesel also exhibit excellent lubricity, even exceeding that of methyl esters. These minor components are at least partially responsible for the lubricity of low-level blends of biodiesel with petrodiesel fuels. Beyond this effect, a sequence of lubricity-imparting moieties COOH > CHO > OH > COOCH3 > C=O > C-O-C was established for C10 compounds. Another sequence of lubricity improvement is O > N > S as was shown for C3 compounds with OH, NH2 and SH groups. Furthermore, both ball and disk wear scar data in the relevant HFRR lubricity test can be used for assessing lubricity.