Molecular dynamics simulation on the interfacial features of phenol extraction by TBP/dodecane in water

We studied the interfacial features and extraction process of phenol by molecular dynamics simulations using the GROMACS software package. The systems of organic phase with varying TBP concentrations and aqueous phase with varying phenol concentrations were simulated. The density profiles of the interfacial features were calculated and they indicated that tributyl phosphate (TBP) gathers at the water/dodecane interface and creates an indistinct and broad interface. TBP can form 1:1, 1:2 and 2:3 complexes with water and a 1:1 complex with phenol. The radial distribution function (RDF) of TBP and phenol shows that most of the hydrogen bond interaction distance is 1.8 Å. The mean square displacements (MSDs) of water and phenol for the different systems show that TBP can restrict the migration of water and phenol near the interface.