1. n. [Enhanced Oil Recovery]

The ability of a chemical agent to remove a contaminant from a solid surface. For example, in enhanced oil recovery, a surfactant can be used to remove an oil phase from a mineral surface.

At least two mechanisms can occur:

• The surfactant adsorbs on the contaminated surface and presents its hydrophilic group to the contacting liquid. Thus, the surface behaves hydrophilically and repels macroscopic oil drops.
• The surfactant adsorbs to the contaminant. It is energetically more favorable for the combination of surfactant and contaminant to be in solution than to be attached to the surface so the contaminant is solubilized, exposing the mineral surface.