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.