Formulações diesel B10/butanol/etanol/metanol: equilíbrio de fases e ensaios em motor ciclo diesel

Abstract

Among the main sources of energy used in Brazil, diesel oil stands out due to its wide use in road transport, locomotives, and ships. Despite its relevance to the transport sector at the national level, its contribution to the climate imbalances currently observed in the world is undeniable. In this perspective, although it is challenging to reconcile the supply of global energy needs with the preservation of the environment, the ability to reduce undesirable emissions makes diesel/alcohol blends an attractive option. Based on this premise, the present study has the general objective of developing B10/butanol/methanol (DBM) and B10/butanol/ethanol (DBE) diesel blends for use in real engines. The compositions of the formulations were determined based on the construction of equilibrium diagrams at a temperature of 25 ± 2 °C. In order to find a mathematical development capable of representing the experimental data, the NRTL and UNIQUAC models were applied with the aid of the TML computational tool, the latter being the one that generated the lowest mean squared deviation (0.34%). The prepared mixtures were submitted to density tests (ASTM D4052 at 20, 25, and 40 °C), kinematic and dynamic viscosities (ASTM D7042 40 °C), corrosivity (ASTM D130 at 50 °C for 3 h), pour point (ASTM D97), cloud point (ASTM D2500), cold filter plugging point (ASTM D6371) and vapor pressure (ASTM D6378), as well as employed in the construction of power curves in a diesel cycle engine according to the recommendations of the test code of engines (ABNT - NBR ISO 1585). In general, all the compositions studied have characteristics that meet the ANP specifications for road use, although the mixture with the highest percentage of methanol has presented unsatisfactory hourly and specific consumption during combustion in a diesel engine.