Surfactants alkylether carboxylates

Because of their excellent biodegradability, alkylether carboxylates (AECs) (general structure CnH2 +i-0-(CH2-CH2-0)n-CH2-C00 ) are used more frequently today in households for cleaning purposes. From the structure shown in Fig. 2.11.11, mass spectra as observed in the ionisation of AES or non-ionic surfactants of the ethoxy type with equally spaced signals (Am/z 44) can be expected [22],... 

AEOs spiked into raw wastewaters were applied to elaborate an APCI or ESI-LC-MS method to determine non-ionic surfactants after SPE. Ionisation efficiencies of both interface types were compared and the more effective APCI technique then was applied for quantification [334]. Recoveries observed with standard determination methods for surfactants and MS detection techniques for different types of surfactants (e.g. alkylether carboxylates, sulfosuccinates, fatty acid polyglycol amines, quaternary carboxoalkyl ammonium compounds, modified AEOs, EO/ PO compounds, APGs, alkyl polyglucamides, betaine and sulfobetaine) in spiked wastewater samples were compared by applying APCI and/or ESI(-i-/-).Poor recoveries were obtained by standard methods but good results by MS [335]. APCI and... 

Fatty acids and acyl sarcosines may be extracted with petroleum or diethyl ether from an acidified aqueous solution if no other surfactants are present, or with petroleum ether from acidified 50% ethanol if they are. The extract is evaporated and the residue weighed. Alkylether carboxylic acids cannot be quantitatively extracted with petroleum ether. They can be extracted from aqueous solution with chloroform, but they are best determined by two-phase titration with benzethonium chloride in akaline solution (bromophenol blue method) or direct potentiometric acid-base titration. 

At the end of the 1990s statistics show that the non-ionic surfactants achieved the highest growth in production rates world-wide, though anionic surfactants (anionics) maintained the dominant position in the surfactant market. Today they are produced in a larger variety by the petrochemical industry than all other types of surfactants. Their production spectrum covers alkyl sulfates (ASs), secondary alkane sulfonates (SASs) and aryl sulfonates and carboxylates via derivatives of partly fluorinated or perfluorinated alkyl surfactants to compounds with an alkylpolyglycolether substructure combined with an anionic moiety such as alkylether sulfates (AESs), phosphates, phosphonates or carboxylates. 

The use of carboxylic and dicarboxylic acids, SDS, bile salts, organic solvents, and alkylammo-nium ions was explored to study the separation of LAS homologues and positional isomers, - as well as alkylether sulfate oligomers. The MEKC separation of mixtures of the surfactant classes coconut diethanolamide, cocamido propyl betaine, and alkylbenzene sulfonate was studied in either low pH phosphate or high pH borate or dipentylamine buffers containing as surfactants deoxy-cholate or SDS, organic solvents (methanol, acetonitrile, n-propanol, and n-butanol), and anionic solvophobic agents (DOSS, fatty acids). " ... 

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