An experimental investigation was carried out to evaluate the performance and emission
characteristics of vegetable oils blends with diesel oil as an alternative fuel. Virgin and waste
frying vegetable oils of sunflower, corn, soybean and palm oils were collected and characterized
with GC-FID. Nine blends of various vegetable oils and diesel were prepared. The important
chemical and physical properties of the blends (including kinematic viscosity, heat of
combustion, exhaust emissions (SOx and NOx), flash point, pour point, cloud point, sulfur
content, density and specific gravity) were compared to those of diesel oil. Generally, there is no
significant difference between the use of waste or virgin vegetable oils blends with diesel oil.
Among the various blends, those containing up to 30% vegetable oils have viscosity, pour point,
cloud point and density values close to those of diesel oil. These blends have approximately
95% of the heat of combustion, but have the advantages of higher flash point and lower
emissions compared to those of diesel oil. Blends of 30% vegetable oils have comparable
performance and emissions characteristics to those of diesel oil fuel and found to be good
substitute for diesel.