Effect of metal contaminants and antioxidants on the storage stability of Jatropha curcas biodiesel

The present paper deals with the study on the effect of metal contamination on the storage stability of Jatropha curcas biodiesel (JCB). Taking Pyrogallol (PY) as the most effective antioxidant based on the earlier work of the authors, JCB was mixed with different transition metals - Fe, Ni, Mn, Co and Cu in different concentrations with and without PY. Induction period (IP) was measured using Rancimat method (EN 14112). Based on the results, several correlations were developed for assessing the storage stability in terms of IP as a function of antioxidant concentration (A), metal concentration (M) and storage time (T). A comparison between the experimental IP values and those predicted by the correlation showed that about 95% of the predicted data points lie within ±12% deviation lines of the experimental results. This is the first study of its kind being reported showing the relationship of IP with antioxidant concentration, metal contaminants and storage time. The correlations developed can be used to predict the amount of antioxidants required to stabilize the JCB for predefined time period.