An Improved Model for Interfacial Activity of Acidic Oil/Caustic System for Alkaline Flooding

Abstract

In alkaline flooding, Interfaclal properties of acidic oil/aqueous caustic play an important role. Although lots of experimental results concerning the effect of various parameters upon interfacial tension and surface charge density have been reported, the mechanism is still not well clarified. C. J. Radke, T. F. Yen and D. T. Wasan have already presented their chemical models for interfacial phenomena of this system, but they all ignore the possibility of forming micelles in the aqueous phase. This article deals with an improved equilibrium chemical model of acidic oil/caustic system. Taking the effect of NaOH-NaCI concentration on the micelles formation into consideration, an expression of interfacial activity is proposed on the basis of Davies theory of the ionic monolayer. Using kerosene containing oleic acid/aqueous solution of hydroxide-sodium containing sodium chloride as the model system, the data of interficial tension (7) and electrophoretic mobility (U) with various concentration of sodium hydroxide and sodium chloride in aqueous phase and acid value of oil phase are presented. The critical micelle concentration of sodium oleate under the various ionic strength is determined and the relation between the micelle concentration and ionic strength is employed in the simulation calculation. γmin and U max thus obtained from the model calculations agree well with the experimental results in regard to the varying trend of parameters used. The mechanisms for the presence of γ min are also suggested. This model may be used in practical numerical simulation for alkline flooding with reasonable option of physicochemical parameters.

Mechanistic Investigation of LSW/Surfactant/Alkali Synergism for Enhanced Oil Recovery: Fluid–Fluid Interactions

“…34,41,55 In addition, the formation of micelles and compression of the electric double layer at high ionic strength at higher concentrations of alkali could be another reason for this phenomenon. 62 According to the results presented in the Table 5 and Figure 6, the IFT reversal for C 19 TAB surfactant is sharp while gradual for SDBS surfactant. Oleic soap is a water-soluble anionic surfactant, which is produced in situ by the reaction of the alkali agent with saponifiable components of the crude oil, such as carboxylic acids.…”

“…In addition, when the ratio of ionized acid to un-ionized acid equals 1, the minimum IFT is achieved. The main reason for the reversing phenomena observed in Figure is the salting-out effect of the equilibrium shifting, which decreases the concentration of the ionized acid after CMC is achieved. ,, In addition, the formation of micelles and compression of the electric double layer at high ionic strength at higher concentrations of alkali could be another reason for this phenomenon …”

Review on Surfactant Flooding: Phase Behavior, Retention, IFT, and Field Applications

“…139 Tong et al proposed another mechanism for the increase of the IFT at higher alkaline concentration. 161 They proposed that the decrease in the ionic species at high alkali concentration is due to the formation of micelles and the compression of the electric double layer at high ionic strength. 6.1.5.…”

“…After a critical value, the concentration of the ionized acid decreases due to shifting of the equilibrium or due to the salting-out effect . Tong et al proposed another mechanism for the increase of the IFT at higher alkaline concentration . They proposed that the decrease in the ionic species at high alkali concentration is due to the formation of micelles and the compression of the electric double layer at high ionic strength.…”

Investigation of the microscopic displacement mechanisms and macroscopic behavior of alkaline flooding at different wettability conditions in shaly glass micromodels

“…Several authors (deZabala et al, 1982;Ramakrishnan and Wasan, 1983;Sharma and Yen, 1983;Tong et al, 1986) focused on quantifying the alkaline flooding technique by constructing a chemical displacement model. They implemented this purpose by establishing a relationship between IFT and the essential chemical properties of the acidic oil and the flood-water.…”