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G. A. Mamedova
Modification the
natural zeolite of nakhchivan in the alkaline environment
Abstract
Based on the
natural mineral of Nakhchivan, a number of zeolites of different structural
types were synthesized. The modification of the natural zeolite was carried out
under hydrothermal conditions, in aqueous solutions of LiOH, KOH, NaOH and
Ca(OH)2, and also in the presence of mineralizers (LiCl, KCl, NaCl,
CaCl2) in an autoclave. Based on the IR spectroscopic, X-ray phase
and elemental analyzes, it was shown that when hydrothermal treatment, the
natural zeolite is converted to other minerals of important for practices of
zeolite group. It was found that mordenite retains the stability of the
structure in alkali solutions (LiOH, KOH, NaOH, Ca(OH)2) at a
concentration of 1 N at a temperature of up to 100°C for 10 hours. When the
conditions of hydrothermal treatment change a natural zeolite transforms, which
gradually converts it into hydrosodalite through mineral phases: chabasite,
heylandite, clinoptilolite, analcime, phillipsite, faujasite, scapolite,
zeolite M, jismondine, leucite, calculite. The presence of mineralizers in the
medium leads to the production of other structural types of zeolites, as
compared to the thermal solution.
Key words:
chemical modification, natural mineral, mordenite, mineralizer, zeolite,
hydrothermal treatment.
Copyright (C) Chemistry Dept., Moscow State University, 2002
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