Adsorption of Surface Active Ionic Liquids on Different Rock Types under High Salinity Conditions

Abstract

A new class of surface active ionic liquids (SAIL) have been reported to be a greener alternative to the conventional surfactants in enhanced oil recovery (EOR). These SAILs work efficiently under harsh salinity conditions encountered in the reservoir thereby recovering more additional oil during the tertiary oil recovery process. Adsorption mechanism of SAILs on different rock surface is however, not yet reported in the literature. This article highlights adsorption mechanism of three cationic SAILs having different headgroups, viz., imidazolium, pyridinium, pyrrolidinium, on different rock surfaces (crushed natural carbonate rock and crushed sandstone rock). All the SAILs studied here however had the same tail length and same anion (Br−) attached to it. XRD and XPS characterization techniques reveal that the crushed natural carbonate rock contains a substantial amount of silica, thus rendering it a slight negative charge. Static adsorption tests show that the retention efficiency on the natural carbonate type of rock for all the SAILs was lower than the conventional cationic surfactant, CTAB. The adsorption data obtained thereby was examined using four different adsorption isotherm models (Langmuir, Freundlich, Redlich-Peterson, and Sips). Results suggest that Sips adsorption isotherm model can satisfactorily estimate the adsorption of all the surface active agents on the natural carbonate rock. Factors like mineralogical composition of rock surface, presence of divalents, temperature, and structure of surfactants strongly affect the amount of surfactant adsorbed on reservoir rock. In order to evaluate the simultaneous effect all these factors as well as their interdependence on the retention capability of the three SAILs, a design of experiments approach has been employed further in this study. Statistical analysis of the data obtained after performing the full factorial experiments reveal that at high salinity, imidazoluim based SAIL show minimal adsorption on crushed natural carbonate rock at higher temperature. In general, at a given ionic strength, with increasing temperature as the amount of divalent in the aqueous solution increases, the amount of SAIL adsorbed on both the rock types decreases. Electrostatic attraction is the basic mechanism in governing adsorption of SAILs on the two types of rock surfaces. Results presented in this work can be used for EOR schemes.

Conformational Stability of Poly (N-Isopropylacrylamide) Anchored on the Surface of Gold Nanoparticles

“…Especially, the desorption of citrate groups adsorbed on the surface of AuNPs is enhanced by heating. Consequently, the aggregation of AuNPs makes a broadening of the plasmon band accompanied by a decrease in intensity and a slight red-shift [ 1 , 33 ]. For AuNPs-PNIPAM, although the charge density of AuNPs-PNIPAM decreases due to charged citrate groups replaced by PNIPAM without charges, the densely immobilized SH-PNIPAM molecules onto the surface of AuNPs effectively resist AuNPs-PNIPAM aggregation induced by higher temperature.…”

“…With an increase of salt concentration, the zeta potentials become lower due to the decrease in the thickness of the double layer, leading to enhancing the aggregation for both AuNPs-PNIPAM and AuNPs. In addition, this aggregation is further enhanced with increasing temperature due to the reduction of the adsorbed charge species and the increase probabilities of collision [ 33 , 34 ]. Consequently, the shoulder peak ranging from 600 to 800 nm is gradually apparent with increasing temperature for both AuNPs-PNIPAM and AuNPs, and this change is enhanced by the increase of NaCl concentration.…”

Numerical simulation of enhanced oil recovery studies for aqueous gemini surfactant‐polymer‐nanoparticle systems

“…Though both isotherms have their respective behavioral traits and applications, a careful evaluation of adsorption density versus surfactant concentration plots with these theories may help in understanding the molecular arrangement of adsorbed 14‐6‐14 GSs onto sandstone rock. Langmuir model assumes that surfactant molecules form a single layer onto adsorbent rock surfaces, wherein Freundlich model suggests a multiple layer stacking arrangement of adsorbed surfactant species 53 . Langmuir model exhibited better results as compared to Freundlich adsorption model, which was evident from larger values of coefficient of determination ( R 2 ).…”

Numerical Simulation of Enhanced Oil Recovery (EOR) studies for aqueous Gemini Surfactant-Polymer-Nanoparticle systems

“…Though both isotherms have their respective behavioural traits and applications, a careful evaluation of adsorption density versus surfactant concentration plots with these theories may help in understanding the molecular arrangement of adsorbed 14-6-14 GSs onto sandstone rock. Langmuir model assumes that surfactant molecules form a single layer onto adsorbent rock surfaces, wherein Freundlich model suggests a multiple layer stacking arrangement of adsorbed surfactant species [50]. Langmuir model exhibited better results as compared to Freundlich adsorption model, which was evident from larger values of coefficient of determination (R 2 ).…”