Density functional theoretical study of the interaction of geminal zwitterionic liquids with limestone, regarding the behavior of the wettability parameter

Zwitterionic liquids have a wide variety of applications in enhanced oil recovery (EOR). In particular, geminal zwitterionic substances have been used as wettability modifiers of limestone, dolomites, and sandstones at high temperatures and pressures. The understanding of the interaction mechanisms of such molecules with the limestone surface is an important step toward the comprehension of the modification in wettability. In the study here presented, the interaction energies of limestone with geminal zwitterionic liquids of the type bis-N-alkyl polyether were calculated within the framework of the density functional theory (DFT). With the use of the DMOL3 library of the Material Studio Software (a DFT-based computational code), we calculated the interaction energies of the bis-N-alkyl polyether liquids, asphaltene with the limestone rocks.