Systematic study of the effects of novel halogen-free anionic surface active ionic liquid on interfacial tension of water/model oil system.

In this investigation, a novel anionic- halogen-free ionic liquid (IL), 1-butyl-3-methylimidazolium dodecyl sulfate ([C 4 mim][C 12 SO 4 ]), was synthesized and examined for possible application in the chemical enhanced oil recovery (EOR) processes. In this way, the effects of [C 4 mim][C 12 SO 4 ] and NaCl concentrations, temperature and model oil type (aliphatic and aromatic hydrocarbons) on interfacial tensions (IFTs) between [C 4 mim][C 12 SO 4 ] solutions and model oils were systematically investigated. It is surprisingly revealed that the novel SAIL [C 4 mim][C 12 SO 4 ] is highly effective in reducing the IFT of aromatic hydrocarbon/water system, and ultra-low IFT can be achieved in the presence of salinity at higher temperature. Moreover, the interaction energies between [C 4 mim][C 12 SO 4 ] and different model oil molecules were calculated using molecular mechanics, which could further interpret the reasons of ultra-low IFT. [ABSTRACT FROM AUTHOR]