Studies on the Effect of Antioxidants on the Long-term Storage stability and Oxidation Stability of Jatropha Biodiesel

Abstract

Biodiesel is defined as the mono alkyl esters of vegetable oils. Biodiesel is more susceptible to oxidation or autoxidation during long term storage than conventional petro diesel. This paper presents results of studies on the effectiveness of various individual antioxidants to improve the oxidative stability and storage stability of Jatropha biodiesel (JBD).The results of Rancimat experiments show that the induction point (IP) increased substantially on adding certain antioxidants to the Jatropha biodiesel. The study reveals pyrogallol (PY) to be the best antioxidant which showed the best improvement in the oxidative stability of JBD, the induction time being enhanced to 18.62 h at a PY concentration of 3000 ppm at 110⁰C.  The storage stability studies were carried out according to the ASTM standard procedures 1) ASTM 4625 @30⁰C/50 weeks 2) ASTM 4625@43⁰C/ 12 weeks by adding different antioxidants like Butylated hydroxytoluene(BHT), Butylated hydroxyanisole (BHA), Pyrogallol (PY), Gallic acid (GA) and tertiary Butylhydroquinone (TBHQ). The effectiveness of these five antioxidants on JBD was examined at varying loading level during the storage period.