Experimental investigation of the effect of diesel–cotton oil–n-butanol ternary blends on phase stability, engine performance and exhaust emission parameters in a diesel engine

This study focused on the effect of temperature and component concentration on phase stability of diesel–cotton oil–n-butanol ternary blends. Titration method was performed for plotting phase diagrams at different temperatures (−10, −5, 0, 5 and room temperature). Ternary blend of 70% diesel fuel, 20% cotton oil, 10% n-butanol by volume (DCtOnB), which was prepared by the splash-blending method, obtained from titration values at −10 °C temperature was selected for the engine performance and exhaust emission tests. Engine performance test results of DCtOnB showed that average values of brake torque (2.6%), brake power (1.6%), brake thermal efficiency (BTE) (31.2%), brake mean effective pressure (BMEP) (2.3%) and exhaust gas temperature (3.6%) are lower, while brake specific fuel consumption (BSFC) (34.1%) is higher than those of diesel fuel. As for the emissions of the DCtOnB, it was found that carbon monoxide (CO) and carbon dioxide (CO2) emissions reduced significantly at low engine speeds, whereas oxides of nitrogen (NOx) and hydrocarbon (HC) emissions increased, when compared to those of diesel fuel. Taking these facts into account, a blend of 70% diesel fuel, 20% cotton oil and 10% n-butanol was found the most suitable ratio for low temperature behavior due to the satisfactory fuel properties and reduced exhaust emissions.