1070-4272/03/7606-0867 $25.00 C 2003 MAIK [Nauka/Interperiodica]
Russian Journal of Applied Chemistry, Vol. 76, No. 6, 2003, pp. 867!870. Translated from Zhurnal Prikladnoi Khimii, Vol. 76, No. 6, 2003,
Original Russian Text Copyright + 2003 by Maslova, Gerasimova, Makarov, Naidenov, Forsling.
AND INDUSTRIAL INORGANIC CHEMISTRY
A Study of Structure and Surface Properties
of Cleaved Mica Particles
M. V. Maslova, L. G. Gerasimova, V. N. Makarov, V. Naidenov, and W. Forsling
Tananaev Institute of Chemistry and Technology of Rare Elements and Mineral Raw Materials, Kola
Scientific Center, Russian Academy of Sciences, Apatity, Russia
Luleo Technical University, Luleo, Sweden
Received October 9, 2002; in final form, February 2003
Abstract-The structure of cleaved mica particles and the influence of cleavage conditions on surface prop-
erties of mica were studied by IR spectroscopy.
In recent years, there has been considerably in-
creased interest in processing of mining tailings,
whose utilization frequently yields products that are
in short supply.
The consumption of raw mica is mainly limited to
large-plate phlogopite and muscovite, which are start-
ing materials for radio electronics and radio engineer-
ing. At the same time, demand for fine (small-size)
mica is virtually absent.
The problem of full utilization of mica raw ma-
terials can be solved solely by developing new tech-
nologies for utilization of small mica fractions, now
going to wastes. It is known that the crystal size is not
an important parameter for pigments used in manufac-
ture of paint-and-varnish materials, rubber fillers, and
plastics . The finer the initial mica, the lower
the amount of energy consumed for its cleavage and
grinding, and the cheaper the final product obtained.
Splitting and grinding of mica is accompanied by
destruction of the interlayer space, with deformation
or destruction of the crystal lattice and the resulting
change in the surface properties of mica, owing to
the appearance of an uncompensated structural charge
. These changes determine the quality of ground
micas and the possible field of their use.
The aim of this study was to analyze structural
changes and surface properties of phlogopite and
muscovite cleaved by different methods.
Phlogopite used in the study was obtained from
mica-ore-dressing tails of the Kovdor deposit, and
and muscovite was a by-product of mica production in
Karelia. The starting material consisting of 1 0 2-cm
plates was subjected to chemical and electrochemical
cleavage and then ground on a ball mill in wet mode.
The <63-mm fraction was used in the study.
In chemical cleavage, mica was treated with 0.5 M
sulfuric acid for 120 h . Leaching of the structure-
forming (cross-linking) elements disturbs the neutral
charge of a mica pack and leads to its cleavage. Elec-
trochemical cleavage  is based on leaching of po-
tassium ions into the liquid phase on applying a po-
tential difference to an aqueous mica suspension, with
the mica pack disrupted by the uncompensated charge
of the cleavage planes.
The cleaved mica was studied by the diffusion
reflection IR Fourier spectroscopy. The chemical
composition of the samples was determined with an
ICP3QMS mass-spectrometer. The crystallinity of
structure was characterized using a Siemens D 5000
diffractometer, and the specific surface area was meas-
ured by the BET method on a Micrometric 2000 in-
strument. The liquid phase was analyzed with a Per-
kin3Elmer 3100 atomic-adsorption spectrometer, and
the degree of recovery of the components into solution
The data presented in Fig. 1 give insight into
the behavior of the main cross-linking cations of mica
in its splitting. Evidently, the degree of cation leach-
ing is higher in chemical treatment, compared with
electrochemical treatment in a neutral medium. Irre-
spective of a cleavage method, the degree of leaching
of octahedral cations exceeds that for tetrahedral cat-
ions. The decrease in the specific surface area S