Feasibility study of Caesalpinia Bonduc seed methyl ester as a sustainable biodiesel for naturally aspirated diesel engines

In consideration of the increasing concerns regarding environmental degradation and the depletion of fossil fuels, this research endeavors to assess the viability of employing Caesalpinia bonduc seed methyl ester (CBOBD) as a sustainable biodiesel in naturally aspirated diesel engines. Biodiesel was produced through a two-step transesterification process, and the resultant test blends (CBOBD20 to CBOBD100) were critically analyzed in comparison to conventional diesel regarding performance, combustion, and emission characteristics. The CBOBD20 blend demonstrated a brake thermal efficiency (BTE) of 32.64 %, which is merely 4.6 % inferior to that of diesel (34.22 %), while concurrently achieving a 5.7 % reduction in carbon monoxide (CO) emissions and an 8.1 % decrease in hydrocarbon (HC) emissions. Nonetheless, a slight increase of 0.4 % in nitrogen oxides (NOx) emissions was recorded. The exhaust gas temperature (EGT) exhibited a marginal rise, reaching 349.63 °C for CBOBD20 in contrast to 347.57 °C for diesel. Fuel consumption saw an increase of 0.03 kg/kWh for CBOBD20 and 0.05 kg/kWh for CBOBD100. These findings substantiate the technical feasibility of CBOBD20 as a low-emission biodiesel alternative, preserving efficiency levels comparable to diesel while providing significant environmental advantages.