Pine oil–biodiesel blends: A double biofuel strategy to completely eliminate the use of diesel in a diesel engine

Pine oil, synthesized from pine oleoresin, is recently being viewed as a potential renewable source of fuel for diesel engine application. Significantly, the estimated physical and thermal properties of pine oil are suited for its use in diesel engine, with the notable advantages of lower viscosity, boiling point and comparable calorific value with diesel. In this study, we decidedly conceived a strategy to blend it with a biodiesel, instead of diesel, so as to look out for double biofuel, a measure aimed at complete replacement of fossil fuels. As such, in the current investigation, KME (kapok methyl ester), a biodiesel derived from kapok oil, was blended with pine oil in various proportions such as B25P75, B50P50 and B75P25. Significantly, up on blending pine oil with KME, the viscosity, boiling point, cetane number and other properties of the resultant blends were found to be appropriate, as the merits and demerits of one biofuel over the other are mutually balanced. Therefore, the reported blends were subsequently tested for its combustion, performance and emission characteristics in a single cylinder diesel engine. From the experimental investigation, B50P50 blend was found to be amenable for its use in diesel engine without any modification, as the performance and combustion characteristics of the engine was found to be comparable with diesel. Further, the major emissions such as HC (hydrocarbon), CO (carbon monoxide) and smoke for B50P50 were observed to be 8.1%, 18.9% and 12.5% lower than diesel at full load condition, while NOX (oxides of nitrogen) emission was in par with diesel.