Experimental evaluation on oxidation stability of biodiesel/diesel blends with alcohol addition by rancimat instrument and FTIR spectroscopy

Use of alcohols blended with biodiesel as alternative fuel in diesel engine is an attractive solution for depletion and demand of fossil fuels in transportation and industrial applications. Calophyllum Inophyllum is a higher oil yielding species with high heating value and notably non-edible oil. One of the most important criteria used for assessing the quality of biodiesel blended fuel is 'storage oxidation stability'. Deprived oxidation stability is the important technical obstacle associated with the biodiesel commercialization. This study investigated the oxidation stability of biodiesel blends at 100 % (B100) and 20 % (B20) volume concentrations with diesel through induction time determined by Rancimat instrument. Effects of pentanol addition with B20 biodiesel at 10 % (P10) and 15 % (P15) volume concentrations are also analyzed. FTIR spectroscopy characterizes the oxidation variability of all test fuels. It can be concluded that the biodiesel (B100) shows good oxidation stability (I.P = 8.47 h). Addition of pentanol (10 %) enhances the storage ability by 44.57 % than B20, whereas further addition of pentanol (15 %) declines by 19.48 % when compared to P10. More concentration of pentanol weakens the hydrophilic and hydrophobic clusters formed between pentanol/diesel/biodiesel compounds which have been characterized using infra red spectroscopic analysis.