عنوان مجله
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Journal of the Iranian Chemical Society
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چکیده
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Several identification techniques have been used
to study the effect of the preparation method of dealuminated
Y zeolite on catalyst loading. In this paper, NaY
zeolite was dealuminated by chemical operation with ethylenediaminetetraacetic
acid (H4EDTA) treatment. In this
method, extra-framework aluminum species removed from
the supercage of zeolite and therefore increases the Si/Al
ratio and pore volume. Consequently, the loading of the
molybdophosphoric acid (MPA) in the supercage of zeolite
is increases (0.1 g/g equal 0.049 mmol/g support) in EDTA
treatment (MPA-MDAZY) in comparison with (0.0875 g/g
equal 0.043 mmol/g support) in hydrothermal method
(MPA-DAZY). These results were also confirmed by XRF,
AAS, FTIR, SEM, BET, XRD and WDX analysis. Reducing
of the reaction time and increasing of the catalytic
activity of EDTA treatment toward hydrothermal method
can be related to the high catalyst loading based on removing
of extra-framework aluminum. The catalytic activity of
two catalysts has been compared in the xanthenes synthesis reactions.
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