45244-49-3

This invention relates to an anionic-cationic-nonionic surfactant as substantially represented by the formula (I), production and use thereof in tertiary oil recovery. The anionic-cationic-nonionic surfactant of this invention exhibits significantly improved interfacial activity and stability as compared with the prior art. With the present anionic-cationic-nonionic surfactant, a flooding fluid composition for tertiary oil recovery with improved oil displacement efficiency and oil washing capability as compared with the prior art could be produced. In the formula (I), each group is as defined in the specification.

In this study, cationic surfactants having different alkyl chain lengths were prepared by amidation of lauric, myristic, palmitic, stearic, oleic acids with diethylene triamine. The products were quaternized using chlo-roacetic acid. The chemical structure of the prepared compounds was elucidated using different spectroscopic techniques. The critical micelle concentration (CMC) and the free energy of the micellization and adsorption of these compounds were determined by surface tension and conductivity measurements. The products were evaluated as surface-active agents as well as corrosion inhibitors for steel alloy in 1 M hydrochloric and sulfuric acid, the results indicate that these materials have a high efficiency as corrosion inhibitors and as surface active agents. These results were correlated with the chemical structure of the prepared compounds. AOCS 2009.