The effectiveness of antioxidant additives on the oxidation stability of jatropha biodiesel

ABSTRACT

Biodiesel holds advantages such as a reduced level of exhaust emissions of carbon monoxide, unburned hydrocarbon emissions, and particulate matter over diesel fuel, which draw attention due to its environmental-friendly, readily available, and easily decomposable nature. However, the problem that limits the usage of biodiesel as a fuel in engine is fuel degradation and oxidation reaction over a period of time. Thus, to address the drawback of degradation and oxidation problem of biodiesel, an experimental investigation on the effect of antioxidant additives on the oxidation stability of a jatropha biodiesel (JBD) is conducted by using Rancimat apparatus. The antioxidants such as N,N-Dimethyl p-phenylenediamine dihydrochloride (NPPD), succinimide (SU), and N-phenyl-p-phenylenediamine (DPPD) are dispersed at various proportions (500, 1000, 1500, and 2000 ppm) with JBD. The experimental results established increased the oxidation stability for the antioxidant-dispersed JBD compared with the JBD. The NPPD at concentrations of 500, 1000, 1500, and 2000 ppm improved the induction time from 2.5 h for JBD to 15.6, 20.5, 30.2, and 38.4 h, respectively. Among the test fuels are kept for the storage of 21 days, JBD dispersed with NPPD at a concentration of 2000 ppm has improved the higher oxidation stability among the other antioxidant-dispersed test fuels.

KEYWORDS:

• Antioxidants
• jatropha biodiesel
• oxidation stability
• parts per million
• Rancimat