Effects of Diphenylamine on Binary Systems of Acetone + Ethanol, Acetone + Cyclohexane, and Ethanol + Cyclohexane at 101.3 kPa: Vapor–Liquid Equilibrium Measurement and Molecular Simulation

Abstract

The recovery of organic solvents is important in the process of extracting nitrocellulose from waste propellants. Until now, the influence of diphenylamine from waste propellants on organic solvents has not been clear, which is a critical factor for their separation. In this paper, binary and ternary vapor–liquid equilibrium systems referring to mixtures containing diphenylamine, acetone, ethanol, and cyclohexane at 101.3 kPa were investigated systemically. The experimental results shows that diphenylamine increased the equilibrium temperature, decreased the relative volatility of organic solvents, and has a limited effect on the azeotropic composition for the systems of acetone + cyclohexane and ethanol + cyclohexane. In addition, a molecular dynamics analysis through GROMACS software was adopted to explore the interaction between diphenylamine and the above solvents, and the results show that the order of magnitude of the interaction force is: acetone is greater than ethanol and ethanol is greater than cyclohexane. This might be the main reason for the decreasing relative volatility of organic solvents.