This study examines the latest trends in the development of biodiesel blends for marine propulsion engines, with the goal of making our oceans cleaner and more sustainable. In this study, we examine various biofuels, including rapeseed, pyrolysis, olive, soybean, waste cooking, jatropha,
sunflower, transformer, and palm biodiesel, by testing them in a four-stroke marine diesel engine. One of the primary challenges in the fuel industry is the high levels of pollutants emitted by diesel engines, which can have a negative impact on human health. Our objective is to present
the methods used to develop these eco-friendly biodiesel blends. We also examine key performance metrics, such as brake thermal efficiency, fuel consumption, and combustion characteristics (heat-release rates and cylinder pressures), for various biodiesels in marine engines. The use of innovative additives in these biofuels is notable because it confers multiple benefits. Our findings show that all biodiesel blends tested help reduce harmful emissions such as carbon monoxide(CO),hydrocarbons(HC),carbon dioxide (CO2), and nitrogen oxides (NOx), when compared to traditional diesel fuel. This improvement is due to the favorable physical properties of these blends, which not only meet ASTM standards but also fulfill all requirements for diesel fuel.