Adsorption of a switchable cationic surfactant on natural carbonate minerals

Leyu Cui, Kun Ma, Ahmed Abdala, Lucas J. Lu, Ivan Tanakov, Sibani L. Biswal, George J. Hirasaki

Research output: Chapter in Book/Report/Conference proceedingConference contribution

2 Citations (Scopus)


A switchable cationic surfactant, e.g., tertiary amine surfactant Ethomeen C12, has been previously described as a surfactant that can be injected in high pressure CO2 for foam mobility control. C12 can dissolve in high pressure CO2 as a nonionic surfactant and equilibrate with brine as a cationic surfactant. Here we describe the adsorption characteristics of this surfactant in carbonate formation materials. The adsorption of this surfactant is sensitive to the equilibrium pH, the electrolyte composition of the brine, and the minerals in carbonate formation materials. Pure C12 is a nonionic surfactant. When it is mixed with brine, the solution has high pH and limited solubility. However, when the surfactant solution in brine is equilibrated with high pressure CO2, the pH is about 4, the surfactant switches to a cationic surfactant and becomes soluble. Thus the adsorption is also a function of pH. The adsorption of C12 on calcite at low pH is low, e.g., 0.5 mg/m2. However, if the carbonate formation contains silica or clays, the adsorption is high, as is typical for cationic surfactants. The adsorption of C12 on silica decreases with increase in divalent (Ca2+ and Mg2+) and trivalent (Al3-) cations. This is due to the competition for the negatively charged silica sites between the multivalent cations and the monovalent cationic surfactant. An additional effect of the presence of divalent cations in the brine is that it reduces the dissolution of calcite or dolomite in presence of high-pressure CO2. The dissolution of calcite and dolomite is harmful because of formation damage and increased alkalinity. The latter raises the pH and thus increases adsorption of C12 or even cause surfactant precipitation.

Original languageEnglish
Title of host publicationSociety of Petroleum Engineers - 19th SPE Improved Oil Recovery Symposium, IOR 2014
PublisherSociety of Petroleum Engineers (SPE)
Number of pages16
ISBN (Print)9781632663863
Publication statusPublished - 2014
Externally publishedYes
Event19th SPE Improved Oil Recovery Symposium, IOR 2014 - Tulsa, OK, United States
Duration: 12 Apr 201416 Apr 2014


Other19th SPE Improved Oil Recovery Symposium, IOR 2014
CountryUnited States
CityTulsa, OK


ASJC Scopus subject areas

  • Chemical Engineering(all)
  • Energy Engineering and Power Technology

Cite this

Cui, L., Ma, K., Abdala, A., Lu, L. J., Tanakov, I., Biswal, S. L., & Hirasaki, G. J. (2014). Adsorption of a switchable cationic surfactant on natural carbonate minerals. In Society of Petroleum Engineers - 19th SPE Improved Oil Recovery Symposium, IOR 2014 (Vol. 1, pp. 163-178). Society of Petroleum Engineers (SPE).