Effect of diesel–microalgae biodiesel–butanol blends on performance and emissions of diesel engine

• The manuscript presents availability of butanol–microalgae biodiesel–diesel blends as fuel in diesel engines.
• Fuel properties of blends were determined.
• The engine performance tests were carried out.
• Microalgae biodiesel was identified as a promising alternative fuel and butanol was identified as a promising additive.

In this work, the commercially available diesel fuel (D), diesel (80%)–microalgae biodiesel (20%) (by volume) (D80B20), diesel (70%)–microalgae biodiesel (20%)–butanol (10%) (D70B20But10) and diesel (60%)–microalgae biodiesel (20%)–butanol (20%) (D60B20But20) fuels were tested to evaluate the effects of the fuel blends on the performance and exhaust emissions of a diesel engine. Engine performance parameters and exhaust gas emissions such as nitrogen oxides, carbon monoxide and smoke opacity were measured. The results showed that; although butanol addition caused a slight reduction in torque and brake power values, the emission values of the engine were improved. Therefore, butanol can be used as a very promising additive to diesel–microalgae biodiesel blends.