Influence of blending soybean, sunflower, colza, corn, cottonseed, and residual cooking oil methyl biodiesels on the oxidation stability

摘要

Binary mixtures of soybean (SbMB), sunflower (SfMB), colza (CzMB), corn (CoMB), cottonseed (CsMB), and residual cooking oil (RMB) methyl biodiesels were prepared and the oxidation stability (induction period, IP) was measured. CoMB, SbMB, and particularly CzMB improved the oxidation stability of the binary mixtures, which was in agreement with measurements of polyunsaturated fatty acid content and antioxidants (TBHQ) originating from the vegetable oils used for biodiesel production. The oxidation stability of biodiesels with low oxidation stability such as CsMB and RMB was improved through blending with 90% (w/w) SbMB to satisfy EN 14214 (IP ＞ 6 h). Considering ASTM D6751 (IP ＞ 3 h), the oxidation stability of SfMB (0.88 h) was improved by blending with 60% (w/w) SbMB while RMB only required 10% (w/w) SbMB in order to attend ASTM requirements. CzMB presented the highest IP value and therefore is the most effective blender to biodiesels with low oxidation stability. On the other hand, soybean oil is one of the major feedstocks for biodiesel production in the world and the use of SbMB as a common blending to other biodiesels such as CsMB, RMB and SfMB is demonstrated to be an alternative solution to prepare biofuels with improved oxidation stability.