Properties and Phase Behavior of Water-in-Diesel Microemulsion Fuels Stabilized by Nonionic Surfactants in Combination with Aliphatic Alcohol

Abstract

We investigate the properties and phase behavior of the water–diesel fuel–Neonol AF 9-6/2-ethylhexanol system, which is regarded as a promising microemulsion fuel. A pseudoternary diagram of the system has been obtained. In the diesel fuel/water (DF/W) ratio ranging from 98:2 to 50:50 and the emulsifier concentration of 8–40 vol %, a region of microemulsions has been distinguished, generating particular interest as an alternative fuel. In the region under study, a reverse micellar phase L2 has existed predominantly. Fish-cut diagrams have been obtained for the DF/W ratios in the emulsifier concentration–temperature coordinates. An increase in the water fraction in microemulsions significantly has narrowed the range of their stability. The critical changes of microemulsion properties have been identified using the fish-cut diagrams. We have established the empirical relationship among the phase inversion temperature, the emulsifier concentration in the phase inversion point, and the water fraction in microemulsions.