Experimental analysis of Sterculia foetida biodiesel and butanol blends as a renewable and eco-friendly fuel

The current research intended to investigate the performance, emission and combustion characteristics of Sterculia foetida biodiesel blending with n-butanol at two different proportions (5% and 10%). The non-edible nature of the Sterculia foetida kernel oil favored choosing as feedstock. It comprises more than 70% of sterculic acid, a cyclopropane ring in its chemical structure. The base-catalyzed transesterification process converted Sterculia foetida kernel oil into biodiesel. The n-butanol additive was added in 5% & 10% volume as an oxygenated fuel to S. foetida / diesel blends for reducing emissions and improving thermal efficiency. Investigations revealed that brake thermal efficiency was improved by adding n-butanol in the blends compared with 20% S. foetida biodiesel + 80% Diesel. The emissions such as carbon monoxide, smoke opacity and hydrocarbons have significantly reduced vis-à-vis standard diesel. The oxides of nitrogen (NOX) and carbon dioxide (CO2) decreased relative to 20% S. foetida biodiesel + 80% Diesel. The analysis in combustion registered an improvement for butanol/diesel/biodiesel blends relative to S. foetida biodiesel owing to the innate content of oxygen in Heat Release Rate and In-Cylinder Pressure. Hence the addition of butanol with S. foetida biodiesel appears as a good substitute for straight diesel.