2008, №4

pp. 11-34

Kinetics and mechanism of doped corundum structure formation in water fluid

2008, №4

сс. 11-34

Quote

Yu.D. Ivakin, M.N. Danchevskaya, O.G. Ovchinnikova, G.P. Muravieva, V.A. Kreisberg.

Key words: supercritical CO2, inactivation, sterilization, microorganisms

The kinetics and mechanism of corundum formation from hydrargillite in a water fluid in sub- and supercritical conditions in the presence of manganese ions are investigated. It was established that the formation of corundum structure with uniform distribution of manganese ions takes place due to a high solid-phase mobility, which arises in the conditions of quasi-equilibrium dehydroxylation of hydrargillite solid matrix in a water fluid. During isomorphous substitution of Al+3 ions by manganese ions, the composite defects containing Mn2+ and Mn4+ ions with hydroxyl groups and oxygen vacancies are formed. The corundum samples doped with manganese exhibits ferromagnetic properties at room temperature.