Russian Journal of Applied Chemistry, 2010, Vol. 83, No. 1, pp. 54−57.
Pleiades Publishing, Ltd., 2010.
Original Russian Text
Zh.K. Tukhmetova, Sh.B. Kasenova, I.M. Oskembekov, S.M. Adekenov, B.K. Kasenov, Zh.S. Nurmaganbetov, 2010, published in Zhurnal
Prikladnoi Khimii, 2010, Vol. 83, No. 1, pp. 56−59.
OF SYSTEMS AND PROCESSES
Calorimetry of Dissolution of Peganine Methyl Iodide
and Calculation of the Standard Enthalpy
of Formation of a Number of Its Analogs
Zh. K. Tukhmetova, Sh. B. Kasenova, I. M. Oskembekov,
S. M. Adekenov, B. K. Kasenov, and Zh. S. Nurmaganbetov
Fotokhimiya Research and Production Center, Joint-Stock Company, Karaganda, Republic of Kazakhstan
Received August 21, 2008
Abstract—Catalytic thermal destruction of ethylenediaminetetraacetic acid and its complexes with nickel, iron,
and cobalt in nitrate solutions on carbon materials (activated unwoven material, sibunite, and BAU-A activated
carbon) was studied. The activation energies of thermal destruction were calculated.
Recently physical chemists have been strongly
interested in analysis of thermochemical and
thermodynamic characteristics of natural compounds
exhibiting biological activity. It should be noted that
many derivatives of natural alkaloids possess unique
The goal of this study was to experimentally determine
the enthalpy of dissolution of methyl iodide of alkalod
peganine in water and to calculate its standard enthalpy
of formation and that for a number of other derivatives
of this alkaloid.
The compound with empirical formula C
and melting point of 165–167°C has been synthesized for
the ﬁ rst time at the laboratory of chemistry of alkaloids,
Fotokhimiya Research and Production Center, Joint-
Stock Company (Karaganda).
Isothermal calorimetry, a reliable technique for
determining the fundamental thermochemical constant,
standard enthalpy of dissolution of compounds, was
chosen for studying the heat of dissolution.
Our study was performed on a commercial DAK-
I-IA automated differential calorimeter with working
temperature in the range 25–200°C and an error in
measuring the heat release energy not exceeding 20
μV . The calorimeter measures the integral heat ﬂ ux
from the ampule with substances through differentially
connected thermobatteries and a massive central
microcalorimeter unit. In the microcalorimeter, physical
processes of heat release (heat absorption) occur in
the working cell. A massive calorimetric unit with two
calorimetric cells is placed in a cylindrical passive
thermostat. The calorimetric cell is constituted by
a cartridge and a thermostat unit with vertical slots and
thermopiles between these slots. The thermopiles are
welded into two differentially connected thermobatteries:
measuring and compensatory. A calibration heater in
which a metallic ampule with a substance under study is
placed is situated in the internal cartridge.
A portion of a substance under study, weighed on an
analytical balance with a precision of four decimal places,
was placed in the wire-mesh cup of a stopper, which was
then inserted into a vessel with a metallic ampule and
a rod. The 8-cm
ampule contained 5 ml of the solvent.
The ampule was heated to the temperature of experiment
(25°C) and then was introduced into the calorimetric
cell. The substance was preliminarily thermostated for
2 h. After the thermal equilibrium between the cells
was attained, as indicated by a record on the chart strip
of a KSP-4 self-recorder, the “experimental zero” was
set. The stopper was pushed out by pressing the knob
on the rod and the energy of heat release was measured