Survey of Straight Vegetable Oil Composition Impact on Combustion Properties

The combustion of straight vegetable oil (SVO) in internal combustion engines has shown conflicting results in emissions, power, and engine longevity. Many early studies suggested that SVO should not be considered for long term use in diesel engines. However, waste vegetable oil has been fueling adapted vehicles in progressive communities for years. The issues involved in the combustion of SVO or pure plant oils are complex. Engine injection systems, oil type, lipid acid ratio, and fuel temperature all have significant impact on the engine performance and emissions. A review of published studies of SVO combustion with a focus on known SVO composition and chemical structure reveals trends which merit further study. Future engine tests with known vegetable oil profiles will add significantly to the progression of SVO use in engines.