Equilibrium and Transport Properties of Primary, Secondary and Tertiary Amines by Molecular Simulation

Gustavo A. Orozco (1, 2) , Carlos Nieto-Draghi (1) , Allan D. Mackie (2) , Véronique Lachet (1)

1 IFPEN - IFP Energies nouvelles
2 Departament d'Enginyeria Quimica

Using molecular simulation techniques such as Monte-Carlo (MC) and molecular dynamics (MD), we present several simulation results of thermodynamic and transport properties for primary, secondary and tertiary amines. These calculations are based on a recently proposed force field for amines that follows the Anisotropic United Atom approach (AUA). Differentamine molecules have been studied, including n-ButylAmine, di-n-ButylAmine, tri-n-ButylAmine and 1,4-ButaneDiAmine for primary, secondary, tertiary and multi-functional amines respectively. For the transport properties, we have calculated the viscosity coefficients as a function of temperature using the isothermal-isobaric (NPT) ensemble. In the case of the pure components, we have investigated different thermodynamic properties using NVT Gibbs ensemble simulations such asliquid-vapor phase equilibrium diagrams, vaporization enthalpies, vapor pressures, normal boiling points, critical temperatures and critical densities. We have also calculated the excess enthalpies for water-n-ButylAmine and n-heptane-n-ButylAmine mixtures using Monte-Carlo simulations in the NPT ensemble. In addition, we present the calculation of liquid-vapor surface tensions of n-Butyl-Amine using a two-phase NVT simulation as well as the radial distribution functions. Finally, we have investigated the physical Henry constants of nitrous oxide (N2O) and nitrogen (N2) in an aqueoussolutions of n-ButylAmine. In general, we found a good agreement between the available experimental information and our simulation results for all the studied properties, ratifying the predictive capability of the AUA force field for amines.

Keywords: Transport properties; Amines; Molecular dynamic simulation

Domains: Chemical Sciences; Polymers; Modeling and Simulation; Chemical Physics [physics.chem-ph]; Materials

Gustavo A. Orozco, Carlos Nieto-Draghi, Allan D. Mackie, Véronique Lachet. Equilibrium and Transport Properties of Primary, Secondary and Tertiary Amines by Molecular Simulation. Oil & Gas Science and Technology - Revue d'IFP Energies nouvelles, 2014, 69 (5), pp.833-849. ⟨10.2516/ogst/2013144⟩. ⟨hal-01085315⟩