PHASE TRANSFORMATIONS OF NATURAL ZEOLITES under ACID AND ALKALI TREATMENTS
Abstract
The change of zeolite properties of the ‘Noyemberyanskoe’ deposit (Armenia) after their processing with alkaline and acidic solutions (16 mol/dm3 ) has been studied by Xray diffraction and dip pycnometry. It has been established that chemical composition and specific total pore volume of clinoptilolite were changed, and also new phases, such as sodalite, gismondine and fillipsite, were formed at sodium hydroxide concentration of ≥ 2 mol/dm3 . It has been found that increasing the hydrochloric acid concentration up to ≈ 6 mol/dm3 leads to size and form change of clinoptilolite sorption channels, and further increase causes its destruction. The method of lowtemperature nitrogen adsorptiondesorption proved the presence of mesoporous constituent in a clinoptilolite rock.
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About the Authors
A. O. Sargsyan
Yerevan State University
Armenia
Armenia
O. A. Sargsyan
Yerevan State University
Armenia
Armenia
L. R. Harutyunyan
Yerevan State University
Armenia
Armenia
G. G. Badalyan
Yerevan State University
Armenia
Armenia
I. A. Petrosyan
Yerevan State University
Armenia
Armenia
R. S. Harutyunyan
Yerevan State University
Armenia
Armenia
T. F. Kouznetsova
Institute of General and Inorganic Chemistry of the National Academy of Sciences of Belarus
Belarus
Belarus
A. I. Ivanets
Institute of General and Inorganic Chemistry of the National Academy of Sciences of Belarus
Belarus
Belarus
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