ISSN 1070-4272, Russian Journal of Applied Chemistry, 2015, Vol. 88, No. 12, pp. 1981−1985. © Pleiades Publishing, Ltd., 2015.
Original Russian Text © Yu.G. Khabarov, N.Yu. Kuzyakov, G.V. Komarova, V.A. Veshnyakov, A.A. Patrakeev,
2015, published in Zhurnal Prikladnoi Khimii, 2015,
Vol. 88, No. 12, pp. 1734−1738.
Synthesis of a Magnetically Active Compound in the Presence
of Technical-Grade Lignosulfonates
Yu. G. Khabarov, N. Yu. Kuzyakov, G. V. Komarova,
V. A. Veshnyakov, and A. A. Patrakeev
Northern (Arctic) Federal University named after Lomonosov, nab. Severnoi Dviny 17, Arkhangelsk, 163002 Russia
Received October 30, 2015
Abstract—The conditions of the synthesis of a magnetically active compound by redox transformation of iron(II)
and chromium(VI) ions were determined. Under the synthesis conditions, the chromium compounds are recovered
from the solution virtually completely. The use of technical-grade lignosulfonates in the step of the condensation
of the magnetically active compound leads to considerable enhancement of the magnetic activity.
Owing to high practical importance of magnetically
active compounds, researchers’ attention is steadily fo-
cused on the development of new procedures of their
synthesis, on study of the properties, and on search for
new ﬁ elds of their application.
Typical magnetically active compounds (MCs) are
) and ferrites of some metals (MFe
Magnetite is a magnetically ordered material exhib-
iting ferromagnetic properties. It has an inverse spinel
crystal structure in which iron(II) cations and a half
of iron(III) cations are arranged in alternating crystal-
lographic layers. The moments of the iron(III) ions are
compensated, and the magnetic moment is formed by
parallel ordering of spins of iron(II) ions. Minimization
of the total energy composed of the exchange energy,
crystallographic anisotropy energy, magnetostatic en-
ergy, and magnetostriction energy is responsible for the
domain structure. Numerous methods have been devel-
oped for preparing MCs.
Magnetite is often prepared by the condensation pro-
cedure based on the reaction involving bi- and trivalent
iron cations [1–4] at their 1 : 2 molar ratio and pH in the
interval 8–14. The shape, composition, size, and prop-
erties of the particles are inﬂ uenced by the kind of the
iron salt, Fe
ratio , reaction temperature ,
pH , kind of the base, and stirring rate .
Numerous synthesis methods, including those yield-
ing magnetite with particles of nanometric size, suitable
for preparing magnetic ﬂ uids, have been developed by
now. Magnetite can be synthesized by the electrochemi-
cal method  and by partial reduction of iron(III) cat-
Procedures for preparing a magnetically active com-
pound of magnetite type on the basis of an iron(II) salt
only are used more seldom.
Technical-grade lignosulfonates (LSTs) have been
used instead of commonly used oleic acid as stabilizers
for a magnetic liquid based on magnetite that has been
prepared from bi- and trivalent iron salts after prolonged
heat treatment. The LSTs modiﬁ ed by nitrosation ac-
quire an unusual property: Their use in the synthesis of
MCs from iron(II) sulfate allows MCs to be prepared as
a nanosized colloid formed upon peptization of the pre-
cipitate that is the initial condensation product [13, 14].
The condensation of a magnetically active compound
initially yields coarsely dispersed aggregates, which
gradually undergo sedimentation and acquire magnetic
It was interesting to examine by physicochemical
methods the possibility of preparing a magnetically
active compounds by redox reactions of iron(II) and
chromium(VI) ions in the presence of lignosulfonates.