Physicochemical Characterization of Water-Butanol-Diesel Blends for Enhanced Fuel Performance Analysis

Abstract

This study investigates the physicochemical properties of water-butanol-diesel (WBD) fuel blends to assess their suitability as alternative fuels for diesel engines. The blends analyzed include diesel (D) and emulsified mixtures containing 5% water and varying butanol content: W5DBu5, W5DBu10, and W5DBu15. Key parameters evaluated are density, kinematic viscosity, heating value, cetane number, specific heat capacity, flash point, and oxygen content. Results show that density decreases with increased butanol proportion, ranging from 998 kg/m³ for water to 827.5 kg/m³ for diesel, with W5DBu5 exhibiting a 1.0% lower density than diesel. Kinematic viscosity at 40°C increases slightly with butanol addition, with W5DBu15 showing the highest viscosity at 2.7 mm²/s. The heating value reduces as butanol content rises, with W5DBu15 recording a 15% lower heating value than pure diesel. Cetane number analysis reveals that diesel achieves the highest ignition quality, while W5DBu blends demonstrate extended ignition delays. Water exhibits the highest specific heat capacity, whereas diesel presents the lowest, indicating potential for improved energy absorption in blended fuels. Flashpoint analysis shows a decrease from diesel to W5DBu15, implying changes in ignition safety. Finally, oxygen content increases with water and butanol, with water reaching 89%, enhancing combustion efficiency. These findings demonstrate that WBD blends, particularly W5DBu5 and W5DBu10, offer promising fuel characteristics for optimized engine performance while potentially reducing emissions.