ISSN 1070-4272, Russian Journal of Applied Chemistry, 2016, Vol. 89, No. 5, pp. 732í738. © Pleiades Publishing, Ltd., 2016.
Original Russian Text © E.A. Pakhnutova, Yu.G. Slizhov, A.I. Makarycheva, 2016, published in Zhurnal Prikladnoi Khimii, 2016, Vol. 89, No. 5, pp. 597í604.
INORGANIC SYNTHESIS AND INDUSTRIAL
Use of Silochrome with Grafted Layers of Transition Metal
Acetonates for Sorption Concentration of Volatile Organic
Substances from Aqueous Media
E. A. Pakhnutova, Yu. G. Slizhov, and A. I. Makarycheva
National Research Tomsk State University, pr. Lenina 36, Tomsk, 634050 Russia
Received March 29, 2016
Abstract—Sorbents based on silica of Silochrome S-120 brand with covalently attached layers of transition
metal acetylacetonates were synthesized. The sorption properties of the resulting chelate-containing materials
were studied and the analytical potential of their application for rapid sorption concentration of volatile organic
compounds from water bodies was evaluated.
Development of high-efficiency methods for
concentration of environment contaminants is a topical
task for modern ecological and analytical chemistry .
The determination of most of volatile organic compounds
(VOCs) is based on the gas-chromatographic method
distinguished by simple equipment, low detection
limits, and high selectivity. The maximum permissible
concentrations (MPCs) of some VOCs may constitute
several micrograms per liter (ppb), and, therefore, it
becomes necessary to use additional concentration.
A variant of the dynamic sorption, the sorption
concentration combined with a static gas extraction [2, 3]
or with a dynamic and continuous extraction [4, 5], and
the purge-and-trap method in which the dynamic sorption
and the gas extraction are combined are attributed to
widely used methods for concentration of volatile organic
substances from water bodies. The last method has an
advantage of making possible the VOC extraction in the
continuous on-line mode [6, 7].
Despite the wide variety of materials used in
concentration, development of new sorbents with
prescribed properties for effective and selective extraction
of various substances and toxicants from rather diverse
objects and a search for new approaches to their correct
determination with preliminary application of sorption
concentration and physicochemical methods are an
important topical task.
Microcomponents are most frequently concentrated
with synthetic polymers , carbon sorbents , and
chemically modified silicas (CMSs). As a rule, the
maximum sorption capacity for VOCs is exhibited by
carbon sorbents. However, the fact that microimpurities
are ﬁ rmly retained in these sorbents makes the desorption
difﬁ cult and restricts their application . The problem
of the thermal desorption of analytes is solved by using
surface-layered sorbents modiﬁ ed with inorganic salts
The common disadvantage of polymeric adsorbents is
their low sorption capacity for polar organic substances,
which gives no way of reaching high concentration
coefficients. Amorphous porous silicas are versatile
sorbents because their structural characteristics (speciﬁ c
surface area, pore diameter and volume, particle size, and
strength) can be varied in the course of synthesis .
In our opinion, of particular interest in this regard
are CMS-based sorption materials and, in particular,
silica gels with grafted layers of chelate complexes. A
characteristic feature of these sorbents is that the sorption
process occurs in a thin surface layer of the modiﬁ er,