A study on oxidation stability improvement of a palm oil‐derived biodiesel by a synthetic antioxidant

Abstract

Biodiesel, an alternative for conventional diesel, can be produced from renewable resources such as vegetable oils. One of the most crucial characteristics of biodiesel fuel is oxidation stability, which significantly influences the stability of biodiesel during prolonged storage. In fact, biodiesel is less resistant against oxidation than the conventional diesel. In order to transcend this problem, additives are employed. This work uses the Rancimat technique to examine the effects of various antioxidants additives on the oxidation stability of different produced biodiesel. The oxidative stability of biodiesel produced from rapeseed, palm, sunflower and waste cooking oil were evaluated after assuring that the properties of used oils and produced biodiesel complied with the ASTM requirements. Palm biodiesel was selected since it showed the highest oxidation stability of 1.32 h. The experimental findings demonstrated that the two antioxidants investigated (phenolhydrazine and thiamine hydrochloride) are boosting oxidation stability, however phenolhydrazine is providing a higher oxidation stability than thiamine hydrochloride. The optimal amount of phenolhydrazine was found to be 2550 ppm and resulted in an oxidation stability of 6 h. This great enhancement of oxidation stability (454%) ascertained that phenolhydrazine is a strong antioxidant to be utilized in order to enhance shelf life of natural source‐derived biodiesels. The mentioned antioxidant was not yet studied in literature which confirms the novelty of our work.