1070-4272/02/7511-1833$27.00C2002 MAIK [Nauka/Interperiodica]
Russian Journal of Applied Chemistry, Vol. 75, No. 11, 2002, pp. 1833!1836. Translated from Zhurnal Prikladnoi Khimii, Vol. 75, No. 11,
2002, pp. 1869!1872.
Original Russian Text Copyright + 2002 by Korenman, Kochetova, Kuchmenko.
OF CHEMISTRY AND TECHNOLOGY
Sensor Analysis of Gases Emitted in Basic Organic Synthesis
Ya. I. Korenman, Zh. Yu. Kochetova, and T. A. Kuchmenko
Voronezh State Technological Academy, Voronezh, Russia
Received October 11, 2001; in final form, May 2002
Abstract-A matrix comprised of eight different sensors based on piezoelectric-crystal resonators was used
for analysis of multicomponent gas mixtures. The resonator electrodes were modified with both known and
unconventional gas-chromatographic sorbents.
Gas emissions from basic organic synthesis consist
of substances belonging to diverse classes, in par-
ticular, alcohols, amines, amides, ketones, aldehydes,
ethers, esters, and aromatic compounds. Volatile
anthropogenic pollutants are able of fast migration to
residential areas; many of them are accumulated in
the biosphere in concentrations posing hazard to
human life. The content of these pollutants should be
strictly controlled [1, 2].
Modern methods of analysis should be prompt,
mobile, sensitive, cost-effective, and accurate. In this
connection, particular attention is now paid to de-
velopment of gas-analyzing sensors. The operation of
these sensors is underlain by transformation of the
analytical signal generated by interaction of the sam-
ple analyzed with the sensitive coating on the elec-
trodes into a physical signal .
Sensor selectivity is governed by the nature of the
sensitive coating (modifier) of the piezoelectric-crystal
resonator. Modifiers should be selective to individual
components or groups of related compounds, exhibit
adhesion to the electrode surface, and afford accurate
determination of pollutants at the levels of their maxi-
mum permissible concentrations (MPCs). Repeated
use of sensors should not markedly affect the main
physical and chemical properties of the modifiers.
The aim of this work was to optimize the detection
of multicomponent gas mixtures emitted in basic
organic synthesis using sensors based on piezoelec-
The experimental setup for static determination of
volatile organic compounds was assembled at the
laboratory from inexpensive units (Fig. 1).
Standard gas mixtures were prepared in a gen-
erator, into which samples were injected under per-
manent stirring of the mixture components with a
stirrer. The required amount of saturated vapors of the
substances under study was injected into the generator
with a syringe via a polyurethane gasket, where the
sample was uniformly diluted to appropriate concen-
trations (MPC, 1/2 MPC, etc.).
The concentrations of the components c, mgm
were calculated by the Mendeleev3Clapeyron equa-
c = 1.22 p
M 0 10
where 1.22 is the proportionality coefficient; p
saturated vapor pressure, mm Hg; M, the molecular
weight; p, atmospheric pressure, Pa; and T, tempera-
Fig. 1. Schematic of the static sensor device for analysis of
gaseous media, involving sample injection: (1) detection
unit, (2) thermostat, (3) resonator with two film-coated
electrodes, (4) polyurethane gasket, and (5) syringe.