engleski

Response characteristics of a novel nonionic surfactant sensor

Nonionic surfactants are surface-active compounds with hydrophobic and hydrophilic moieties. Commercial nonionic surfactants are normally a mixture of homologous structures composed of alkyl chains that differ in the number of carbons and hydrophilic moieties that differ in the number of ethylene oxide (ethoxylate, EO), propylene oxide (propoxylate, PO), and butylene oxide (butoxylate, BO) units. Almost all the analytical methods for determination of polyethoxylated nonionic surfactants are based on the formation of tetraphenylborate salts of pseudocationic complexes of nonionics surfactants with some metal cations (mainly barium) [1-2]. Barium ion forms pseudocationic complexes with ethoxylated nonionic surfactants (EONS) according to the following schema: The “x” value varies depending on the number of ethoxy (EO) units in the surfactant molecule. It was found that one barium ion complexes 10-12 EO groups. The complexing tendencies of the polyethoxylates homologous series containing up to 80 EO units with barium ion have been potentiometrically investigated. The complexation reaction has been followed with a new nonionic surfactant sensor [3]. The composition of complexes has been determined by potentiometric titration using the same surfactant sensor.

nonionic surfactant; pseudocationic complex; sensor

nije evidentirano