摘要 |
A synergistic blend for foaming concentrated brines comprises at least one foaming agent (in an amount between from about 10 to about 90 weight percent of the blend) and a compound of the formula: CnH2n+1-N-[(CH2)mCOOM]2 (I) wherein n is 4 to 11, M is an alkali metal and m is 1 to 3. Especially suitable as foaming agent are quaternary ammonium salts, alkyl betaines, alkylamidopropyl betaines, sulfabetaines, hydroxysultaines, amphoteric perfluorohydrocarbons, as well as alkylether sulfates. Such synergistic blends are especially useful in the foaming of saturated or near saturated brines.
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