Emission and Fuel Properties Analysis of Jatropha and UCO Biodiesel Blends for Combustion Applications

Abstract

This study investigates the production, characterization, and emission performance of biodiesel blends derived from Jatropha Methyl Ester (JME) and Used Cooking Oil Methyl Ester (UCOME). Biodiesel was produced through a two-step transesterification process, resulting in an average yield of 94.3% for JME and 92.0% for UCOME from 9.6 liters of crude oil. Production cost analysis revealed that crude Jatropha oil constituted 83% of the total cost per liter, while UCO contributed only 5.8%, indicating significant economic advantages for waste-based feedstock. Physical properties of the biodiesel blends were assessed and compared to EN 590 (diesel) and EN 14214 (biodiesel) standards. Results showed that increasing biodiesel content in blends raised viscosity, density, specific gravity, and surface tension, while reducing calorific value. Despite these variations, all blends remained within acceptable biodiesel standard limits, making them suitable for industrial burner applications. SO₂ emissions were evaluated using combustion tests across lean, stoichiometric, and rich conditions. Compared to conventional diesel fuel (CDF), B25 UCOME achieved the highest SO₂ reduction of 69% under lean, 58.1% under stoichiometric, and 90.9% under rich conditions. These reductions are attributed to the inherently lower sulphur content in biodiesel. The findings demonstrate the environmental and economic potential of biodiesel blends, particularly UCOME, as cleaner and cost-effective alternatives to fossil fuels in combustion systems.