A. A. Kubasov, L. E. Kitaev, V. V. Yushchenko, Ya. V. Tikhii
The effect of small quantities of water and ammonia on the nature of
adsorption complexes in a zeolite Y
Abstract
The influence of adsorption of small quantities of water and ammonia on
the nature of acid centers in a decationated zeolite Y was studied using the
methods of IR spectroscopy and temperature-programmed desorption of ammonia. It
is shown that ammonia molecules adsorbed on zeolite Lewis centers bind water
molecules. In the case of preliminary adsorption of water its molecules block
strong acid centers in the zeolite, but also are capable to transfer protons to
ammonia molecules. The formed complexes have less stability than ammonium ions
formed on zeolite structural hydroxyl groups. The experimental data confirm the
results of quantum mechanical modeling of the properties of zeolite clusters
with adsorbed molecules of water and ammonia.
Copyright (C) Chemistry Dept., Moscow State University, 2002
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