Russian Journal of Applied Chemistry, 2012, Vol. 85, No. 6, pp. 872−878.
Pleiades Publishing, Ltd., 2012.
Original Russian Text © I.D. Sorokina, A.F. Dresvyannikov, 2012, published in Zhurnal Prikladnoi Khimii, 2012, Vol. 85, No. 6, pp. 888−894.
AND INDUSTRIAL INORGANIC CHEMISTRY
Synthesis of a Water Puriﬁ cation Reagent Based
on the Fe(II), Fe(III), Al(III), Cl
I. D. Sorokina and A. F. Dresvyannikov
Kazan National Research Technological University, Kazan, Tatarstan, Russia
Received July 27, 2011
Abstract—Formation kinetics of a water puriﬁ cation reagent based on the Fe(II), Fe(III), Al(III), Cl
system was studied in relation to the nature and state of the surface of dispersed aluminum, initial concentration
of iron(III) ions, and pH value. The chemical composition of heteronuclear coordination compounds of iron and
aluminum was determined by potentiometry, nuclear magnetic resonance, and X-ray phase analysis.
A study of the fundamental aspects of how
heteronuclear complexes are formed in equilibrium
systems is one of the most important problems of
coordination chemistry, which is closely related to
implementation of innovative chemical technologies.
A study of the complexation of iron(II),(III) and
aluminum(III) in aqueous solutions is rather useful for
substantiation and simulation of chemical processes in
polycomponent systems. The synthetic availability and
broad opportunities for modiﬁ cation of iron(II),(III)
and aluminum(III) complexes create a great potential
for development of complex-forming formulations
with required set of properties on the basis of these
Systems based on oxo and hydroxo compounds of
iron and aluminum attract researchers’ interest because
of the possibility of being used as coagulants for water
clariﬁ cation and a precursor for synthesis of sorbents. It
is known that presence of aluminum(III) can stabilize the
Fe(II)/Fe(III) ratio in the system, which is used in, e.g.,
electroplating for preparing iron-plating electrolytes.
Salts of iron and aluminum are effective reagents
for water puriﬁ cation . Aluminum sulfate and
oxychloride and iron chlorides and sulﬁ des are the most
widely used for this purpose in our country and abroad.
It has been found experimentally that use of mixed
reagents including compounds of aluminum and iron
improves the efﬁ ciency of water puriﬁ cation . It
follows from published data  that iron-aluminum
reagents have a number of advantages over those
containing only a single ingredient, to which belong
the decrease in the residual content of aluminum(III) in
water, faster precipitation of coagulated particles, better
coagulation at low temperatures, and weaker coloration.
The wider zone of optimal pH values, observed when
reagents of this kind are used, is attributed to a wide
diversity of hydrolysis products with their individual
properties , and the accelerated precipitation of
ﬂ akes, to a change of the reagent structure due to a
denser packing of particles.
The main problems encountered in manufacture of
water-purifying reagents with reproducible composition
and properties consist in that the available raw material
resources are to be used and in reliable technological
processes should be developed.
Difﬁ cultly utilizable iron-containing wastes: e.g.,
solutions for etching of carbon steels, which contain up
to 100 g L
iron ions and comparatively high free acid
concentration, solid iron-containing waste in the form
of scale, and metallurgical dust permanently accumulate
in large amounts. Therefore, it is advisable to use these
wastes as raw materials for synthesis of the reagents.