000			02291nab a2200229 4500
005			20260520004411.0
008			260224s2012 xxu ing
041			_aInglés
245	0	0	_aSurfactant systems for EOR in high-temperature
260			_a _b _cmar. 2012
270			_a03/12/2012 ; 03/12/2012
300			_a8 p. ; 11-19
520			_aA systematic study was made of phase behavior of alkoxyglycidylether sulfonates (AGESs). These surfactants were screened with either NaCl-only brines or NaCl-only brines and n-octane at water/oil ratio (WOR) ~1 for temperatures between approximately 85 and 120°C. All test cases were free of alcohols and other cosolvents. Classical Winsor phase behavior was observed in most scans, with optimal salinities ranging from less than 1% NaCl to more than 20% NaCl for AGESs with suitable combinations of hydrophobe and alkoxy chain type [ethylene oxide (EO) or propylene oxide (PO)] and chain length. Oil solubilization was high, indicating that ultralow interfacial tensions existed near optimal conditions. The test results for 120°C at WOR~1 have been summarized in a map, which might provide a useful guide for initial selection of such surfactants for EOR processes. Saline solutions of AGESs separate at elevated temperatures into two liquid phases (the cloud-point phenomenon), which may be problematic when they are injected into high-temperature reservoirs. An example is provided that indicates that this situation can be alleviated by blending suitable AGES and internal olefin sulfonate (IOS) surfactants. Synergy between the two types of surfactant resulted in transparent, single-phase aqueous solutions for some blends, but not for the individual surfactants, over a range of conditions including in synthetic seawater. Such blends are promising because both AGES and IOS surfactants have structural features that can be adjusted during manufacture to give a range of properties to suit reservoir conditions (temperature, salinity, and crude-oil type).
581			_a1
773	0		_tSPE Journal _g17
942			_cARTICULO
100	1		_aPuerto, Maura _952798
100	1		_aHirasaki, George J. _912498
100	1		_aMiller, Clarence A. _952799
100	1		_aBarnes, Julian R. _952800
999			_c187469 _d187469