Composition for use in oil recovery, its method of use, and novel surfactant compounds.

摘要

Betaines containing the morpholine nucleus, some of which are novel per se, are dissolved in sea water or formation water, the concentration of betaine being from 200 to 100,000 ppm to give a surfactant solution suitable for displacing crude oil from a formation in an enhanced oil recovery process, Included in the solution can be an anionic surfactant containing in its structure an ethoxylated benzene ring which shows a synergistic effect with the betaine in lowering the interfacial tension of the surfactant solution against oil. These betaines have high tolerance towards divalent metal cations and high temperature stability as compared with betaines previously proposed for enhanced oil recovery.