High-Performance Multifunctional Fuel Additives Derived from Renewable Fatty Acids and Phosphazene

The increasing need for high-quality diesel fuel can be fulfilled by using environmental friendly, high-performance additives. We have synthesized novel fatty acid-derived multifunctional additives coupled with phosphazene moiety having the backbone of alternative nitrogen and phosphorous atoms which provided stability, while the additives possessed affinity for the metal surface to form a surface-complex film leading to the hindered metal contact and providing friction-reducing and antiwear properties. In addition, the applicability of the synthesized additives was investigated by testing the anti-oxidant and anticorrosion properties in polyethylene glycol (PEG200) which was taken as the reference base fluid. A rotating bomb oxidation test was used to evaluate the anti-oxidant characteristics, and a four-ball test for the tribological properties. Among the synthesized additives, phosphazene ester of erucic acid exhibited the best antiwear and antifriction properties; however, phosphazene ester of oleic acid was found to be the best anti-oxidant additive.