Shea Butter Oil Biodiesel Synthesized Using Snail Shell Heterogeneous Catalyst: Performance and Environmental Impact Analysis in Diesel Engine Applications

Abstract

The implementation of biodiesel in internal combustion engines has been observed to enhance engine performance and mitigate the discharge of toxic gaseous emissions from the engine. In this research, Shea Butter Oil Biodiesel (SBOB) was used to operate a diesel engine to analyze the performance and emissions characteristics. Shea Butter Oil Biodiesel (SBOB) was blended with petroleum diesel in ratios 0:100 (B0), 25:75 (B25), 50:50 (B50), 75:25 (B75), and 100:0 (B100). The torque, brake power (BP), and brake thermal efficiency (BTE) of the engine were determined. Gaseous emissions from the engine’s combustion were characterized using the BOSEAN BH-4S portable multi-gas detector, while the organic emissions compositions were detected and quantified using Gas Chromatography-Mass Spectrometry (GC-MS). The fuel properties of SBOB and its blends were found to be within the range of acceptable standards. However, the carbon content, sulphur content, heating value, and ash content of the blends decreased from 0.68 to 0.12 wt %, 0.04 to 0.00 wt %, 44.2 to 34.2 MJ/kg, and 0.020 to 0.010 wt %, respectively. The engine torque, brake power, BTE, and engine vibrations were found to reduce when the biodiesel blends were used. Besides the diesel fuel, the biodiesel blend, B25, produced the best engine performance characteristics with 8.50 Nm torque, 1780.95 W BP, and 90.29% BTE. The B100 produced the lowest concentrations of carbon emissions, viz. 520 ppm CO and 1.0% CO2. The NO and NO2 concentrations were found to increase for all the biodiesel blends used. The NO and NO2 concentrations were measured as 230 ppm and 210 ppm for B0, respectively, and 250 ppm and 235 ppm for B25, respectively. The research showed that SBOB has improved engine performance and lowered the emissions profile of CO and CO2 compared with petroleum diesel. The GCMS analysis confirmed that some harmful organic compounds were present in the emissions profile obtained from the exhaust samples of the diesel engine at various compositions.