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[资源] 【资源】Preparation of zeolite catalysts 已有3人参与

最近读了几篇分子筛催化的基本、重要文献，大家分享

Zeolite catalysts are successfully applied in hydrocarbon processing and in
chemical conversion processes. Properties which make zeolites versatile catalyst
components are:
Size and shape of the crystallites are variables in catalyst design and are
determined by the synthesis conditions.
The internal surface area is high and thermally very stable compared to
those of the amorphous silicas and aluminas used traditionally in catalyst
preparation.
The pores are well defined and of molecular dimensions, the pore size is
determined by the crystallographic structure.
The pore openings ruling the accessibility of the internal surface may be
subtly changed by ion-exchange, postimpregnation or chemical reaction with
specific compounds, (pore size engineering).
Charge-compensating cations can be removed by ion-exchange.
T-atoms are in most structures highly accessible, their nature determines the
polarity of the surface and its catalytic activity.
The chemical composition of the lattice is dependent on the synthesis
conditions. In many cases the Si/AI ratio may be varied within wide limits and for
some structures also the nature of the T-atoms is a variable.
The chemical composition of the lattice may be changed by the application of
the various techniques for dealumination- and T-site substitution reactions
(secondary synthesis), as a side effect a profound change in the texture of the
zeolite may occur by the formation of mesopores.
The catalytic activity of the surface of a zeolite can be modified by a
treatment with a reactive chemical and this modification may be limited to the outersurface
of the crystals by selection of a reagent, which due to its size, cannot reach
the internal surface.

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http://www.163pan.com/files/80100160h.html
文件名称:
PREPARATION OF ZEOLITE CATALYSTS.pdf
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[ Last edited by buffaloli on 2010-6-5 at 09:48 ]

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