Effect of dispersant added graphene nanoplatelets with diesel-Sterculia foetida seed oil biodiesel blends on diesel engine: engine combustion, performance and exhaust emissions

In this experimental study, the effect of graphene nanoplatelets (GNPs) on the performance, combustion, and emissions of a diesel engine using Sterculia foetida seed oil biodiesel (SFOME20) was investigated. The novelty of the present study is the surface modification of GNPs with a lipophilic surfactant at different ratios to achieve stable dispersion of GNPs in fuel blends. The homogeneity of the nano-additives in the fuel was tested by ultraviolet spectrometry, and an optimized amount of surfactant was found. The GNPs are dispersed in SFOME20 in different compositions such as 25, 50 and 75 ppm. The experiments were performed at a constant speed under different load conditions. Significant improvements in performance were oberved: brake thermal efficiencywas increased by 8.48%, and brake-specific fuel consumption was decreased by 16.53%. Emission levels Hydrocarbon (HC), carbon monoxide (CO) and nitrogen oxides (NOx)) were reduced by 28.3%, 24.16% and 10.43%, respectively, at 50 ppm in SFOME20. Significant improvement in combustion parameters was noted in the form of reduced ignition delay (ID), decreased combustion duration, and improved peak pressure and heat release rate under full load conditions. The GNPs were found to be promising additives for biodiesel blends to improve the overall performance, combustion and emission characteristics of the engine.