Russian Journal of Applied Chemistry, 2012, Vol. 85, No. 4, pp. 594−597.
Pleiades Publishing, Ltd., 2012.
Original Russian Text © Yu.G. Khabarov, I.M. Babkin, V.A. Veshnyakov, 2012, published in Zhurnal Prikladnoi Khimii, 2012, Vol. 85, No. 4, pp. 576−580.
OF SYSTEMS AND PROCESSES
The Inﬂ uence of the Nitrosation Conditions of Lignosulfonates
on the Synthesis of Magnetoactive Compound
Yu. G. Khabarov, I. M. Babkin, and V. A. Veshnyakov
Lomonosov Northern (Arctic) Federal University, Russia
Received December 12, 2011
Abstract—The inﬂ uence of reagent consumption (sodium nitrite and nitric acid) and nitrosation time of ligno-
sulfonic acids on their peptization activity during subsequent synthesis of a magnetoactive compound on the basis
of iron(II) sulfate with the properties of a magnetic ﬂ uid was determined.
Ultradisperse magnetoactive compounds (MCs)
[particles of magnetite (Fe
) or ferrites of composition
] are dispersed phase of magnetic ﬂ uids, which
have ﬂ uidity and can interact with a magnetic ﬁ eld [1,
2]. Magnetic ﬂ uids are synthesized by the methods of
dispersion and condensation. The condensation methods
are based on the reaction involving di- and trivalent iron
↓ + 4H
The condensation performed at the ratio of salts
= 2 : 1 at 70°С and constant agitation results
in the formation of colloidal particles. With the use of
ammonium hydroxide, the temperature may be decreased
to 25–40°С [6–9].
In [10, 11], magnetite-based ferroﬂ uid was obtained
from di- and trivalent iron salts after prolonged thermal
treatment; stabilizers were lignosulfonates (LSs) instead
of the commonly used oleic acid.
Methods of the prepration of magnetically active com-
pound of the magnetite type based solely on iron(II) salt
are rare. Belikov et al.  suggested a method includ-
ing precipitation of iron(II) carbonate from a solution of
iron(II) salt and its subsequent treatment within 55–60°С
for 1 h. However, magnetite synthesized by the above
method has low relative magnetic susceptibility (RMS).
The nitrosation of LSs allows preparation of iron(II)
sulfate-based MC in the form of ultradisperse colloidal
solution with high RMS value.
In the study, the optimal conditions of the LS nitro-
sation were determined to obtain MC with maximum
We used in experiments 65% nitric acid, sodium
hydroxide, iron(II) sulfate heptahydrate (analytical pu-
rity grade), and technical lignosulfonates. From these
reagents we prepared aqueous solutions of the following
concentrations: 1 M NaOH, 10% HNO
, 2.5g l
and 18.6 g l
LS. A solution of iron(II) sulphate was
prepared in a 200-ml volumetric ﬂ ask. To do this, 5.56 g
O were dissolved in distilled water, 16 ml
of 10% acetic acid was added to suppress hydrolysis, and
then distilled water was added to the mark.
LSs were nitrosated in a 100-ml volumetric ﬂ ask
containing 4 ml of a solution of initial LSs, to which
a prescribed volume of 10% nitric acid, 80 ml of distilled
water, and a prescribed volume of the solution of sodium
nitrite were added. Then, distilled water was added to the
mark and the reaction mixture was kept for a necessary
The MC synthesis was performed as follows. Into
a tube, a 10 ml of a solution of initial or nitrosated LSs was
introduced, to which 2 ml of a solution of iron(II) sulfate