Enhanced oil recovery using the ionic liquid trihexyl(tetradecyl)phosphonium chloride: phase behaviour and properties

Abstract

With a decrease in world oil reserves and a higher demand for petroleum and its derived products, the effective exploitation of oil reservoirs has become increasingly important. Enhanced oil recovery (EOR) assisted by surfactants is an effective method for recovering the oil from reservoirs that have lost their drive after the application of primary and secondary recovery methods. This research is aimed at showing the suitability of several ionic liquids as effective replacements for conventional surfactants in EOR. The reservoir fluid has been modelled as a ternary system of water (pure water or aqueous solution of NaCl) plus the ionic liquid trihexyl(tetradecyl)phosphonium chloride plus dodecane. Determination of its liquid-liquid phase equilibrium indicates the formation of a Winsor type III system, with a triphasic region and adjacent biphasic regions. The interfacial tensions in the system corroborate the ability of the ionic liquid to act as a surface active agent, as desirable for its use in an EOR process. A relevant transport property such as viscosity, in addition to density, has been experimentally measured for the equilibrium phases.

Ionic Liquids as Surfactants – Applications as Demulsifiers of Petroleum Emulsions

“…The interfacial tensions in the system corroborate the ability of the IL to act as a surface active agent, as desirable for its use in an EOR process. A relevant transport property such as viscosity, in addition to density, has been experimentally measured for the equilibrium phases [65]. The same research group showed in 2013 that the three-phase system generated when adding trihexamethyl(tetradecyl)phosphonium chloride to the water-oil mixture remain stable in the wide range of temperature and in the presence of salt, in contrast with other system, no cosurfact is required.…”

“…showed the suitability of several ILs as effective replacements for conventional surfactants in EOR [65][66]. The reservoir fluid has been modelled as a ternary system of water (pure water or aqueous solution of NaCl) plus the IL: trihexyl(tetradecyl)phosphonium chloride plus dodecane.…”

Correlation of three-liquid-phase equilibria involving ionic liquids

“…With the aim of confirming the quality of the NRTL model to simultaneously correlate LLE and LLLE data for systems with ionic liquids, we have extended the correlation to other previously determined three-liquid-phase systems involving ionic liquids [33][34][35][36][37][38].…”

“…Most of the predictions of three-phase equilibria with interaction parameters obtained from binary systems do not adequately represent all the regions of the phase diagrams. [33][34][35][36][37][38] are correlated using the NRTL model. The correlations are carried out by simultaneously fitting the binary and ternary LLE data together with the LLLE tie-triangle of the systems.…”

Water-soluble complexes of hydrophobically modified polymer and surface active imidazolium-based ionic liquids for enhancing oil recovery

“…It has been demonstrated that the performance can be notably changed by combinations of this polymer solution with a certain amount of surfactant [7][8][9]. Although the hydrophobically associating polymer-surfactant flooding technique is promising, its application to date has been limited due to the rheology performance of system and the failure in function of surfactant under the reservoir conditions such as poor salt tolerance of anionic surfactant [10]. For these reasons, there is growing interest in finding a new hydrophobically associating polymer-surfactant system whose properties best fit the EOR requirements.…”