Foaming properties, alcohol ethoxylate derivatives

Correlation equations relating surfactant chemical structure to performance characteristics and physical properties have been established. One atmosphere foaming properties of alcohol ethoxyl-ates and alcohol ethoxylate derivatives have been related to surfactant hydrophobe carbon chain length, ethylene oxide content, aqueous phase salinity, and temperature. Similar correlations have been established for critical micelle concentration, surfactant cloud point, and surfactant adsorption. 

Foam exhibits higher apparent viscosity and lower mobility within permeable media than do its separate constituents.(1-3) This lower mobility can be attained by the presence of less than 0.1% surfactant in the aqueous fluid being injected.(4) The foaming properties of surfactants and other properties relevant to surfactant performance in enhanced oil recovery (EOR) processes are dependent upon surfactant chemical structure. Alcohol ethoxylates and alcohol ethoxylate derivatives were chosen to study techniques of relating surfactant performance parameters to chemical structure. These classes of surfactants have been evaluated as mobility control agents in laboratory studies (see references 5 and 6 and references therein). One member of this class of surfactants has been used in three field trials.(7-9) These particular surfactants have well defined structures and chemical structure variables can be assigned numerical values. Commercial products can be manufactured in relatively high purity. 

Alcohol ethoxylates and alcohol ethoxylate derivatives were chosen for study based on their predicted foaming properties, thermal and chemical stability, salinity tolerance, and adsorption characteristics. Table 1 illustrates the classes of surfactants used and the shorthand surfactant naming system employed. Except when noted, surfactants were developmental ENORDET surfactants from Shell Chemical Company or were research samples synthesized in our laboratory or at Koninlijke/Shell Laboratorium, Amsterdam. AES 810-2.6A was obtained from GAF Corporation. 

Foaming properties of alcohol ethoxylates and alcohol ethoxylate derivatives are related to chemical structure features such as hydrophobe size and linearity, ethylene oxide chain length, and the terminating group at the end of the ethylene oxide chain. Foaming properties may be mathematically related to chemical structure parameters using multiple correlation analysis. ... 

Various anionic derivatives of alcohol ethoxylates have been shown to possess improved saline media foaming properties in the... 

These surfactants show poorer wetting and foaming properties in comparison with alcohol derived nonionics. Emulsifying properties are excellent. In general, esters and lower ethoxylates are appropriate for w/o dispersions while higher ethoxylates are more suitable emulsifiers for o/w dispersions. 

Alcohols are hydrocarbon derivatives with hydroxy groups. Primary long-chain C o-Cig alcohols are the most interesting compounds as surfactants. They exhibit all the properties of nonionics with the exception of micelle formation in aqueous solution. Higher aliphatic alcohols are better soluble in oils than in water. They are widely used as co-surfactants/ emulsifiers and foam stabilizers in aqueous solutions of anionic surfactants. Furthermore, alcohols serve as an intermediate raw material in manufacturing water-soluble surfactants, such as ethoxylated products and ether sulphates [7-11]. 

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