INVESTIGATION OF KINETIC OF DEHYDROXYLATION REACTION IN MUSCOVITE. M. T. Dehtyaruk, E. A. Kalinichenko, A. S. Litovchenko, A. M. Kalinichenko, N. N. Bagmut, Institute of Geochemistry, Mineralogy and Oreformation, Ukrainian Academy of Sciences, Palladina prosp., 34, 252680, Kiev-142, Ukraine

Structural transformation of hydroxyl-containing minerals are usually accompanied by destruction of the structural OH- groups (the dehydroxylation reaction). It is followed by partial or complete rebuilding of the crystalline structure. This effect can be evoked by temperature, electric field, radiation etc. At the temperatures above 900 K the dehydroxylation reaction take place in a muscovite.

The kinetics dependences a(t) of the dehydroxylation reaction and the temperature dependence k(T) of the dehydroxylation rate, studied in the muscovite by Electron Spin Resonance method, are presented in this work. Samples of a polycrystalline muscovite (Ukraine) by dimensions 1.0x1.0x0.1 mm had been subjected to the thermal treatment within the temperature range 923 to 1173 K.

The theoretical analysis of experimental data shown that the kinetics curves a(t) is well described by the exponential law. The temperature dependence k(T) can be described by the theory of transitions, induced by fluctuative reparation of a barrier as a result of thermal oscillations of ions in the lattice. On the basis of the kinetic and temperature dependences of the dehydroxylation reaction the two-well curve of proton potential energy was calculated taking into account thermal oscillations of ions in the muscovite structure.