Extractive freezing-out of carbonic acids from aqueous solution into acetonitrile under conditions of action of a field of centrifugal forces

Abstract

In the first time the Extractive freezing-out of monobasic carbonic acids C2-C8 from water into
acetonitrile in the conditions of action of a field of centrifugal forces is studied. Influence of speed of rotor’s
rotation of the centrifuge on amount of the obtained extract is studied. As a result of one procedure of
extraction it is reached 22-37-fold extent of concentration. Application of that extraction method together with
a gas chromatography with flame ionization detecting allowed to reach a determination limit in water of acetic
and propionic acid made 0.1 mg/l, butanoic, pentanoic, hexanoic, heptanoic and octanoic acids 0.05 mg/l. The
obtained extraction’s regularities of analytes keep within a framework of earlier offered theoretical model
based on the sorption mechanism of distribution between a surface of ice and a liquid phase of a nonfreezing
extractant. Prospects of application of a method in the analysis of vegetable objects on the example of
determination of salicylic acid are shown.