| Summary: | 碩士 === 逢甲大學 === 化學工程研究所 === 83 === The properties of the Cu catalyst depends upon the kind of
chelating agents in the preparing process. Two different
chelating agents,ethylenediaminetetraacetic acid (EDTA) and
triethanolamine (TEA),were individually used to prepare seven
different cotents of Cu on γ-alumina support (8.44 ∼24.56
wt%) by EDTA and (7.09∼25.92 wt%) by TEA using the electroless
Cu plating method. The dispersion of Cu particle on γ-alumina
support and the crystalline phase of catalyst were
characterized by Scanning Electron Micrography (SEM) and X-ray
Diffraction (XRD) respectively. The Cu surface area and the
acidity of catalyst were determined individually by the
chemisorption of nitrous oxide and ammonia using the volume
adsorption method in a vacuum apparatus. The catalyst activity
to the dehydrogenation reaction of butanol at the range of
200℃ ∼300℃ was carried out in a fixed-bed flow micro-reactor
and the products were analyzed by an on-line gas chromatography
(GC) using a flame ionization detector (FID). The experiment
results showed that both the dehydration and dehydrogenation
occurred simultaneously. At the same reaction temperature,the
conversion of 2-butanol was higher than that of 1-butanol. The
conversion increased not only with temperature but also with
the Cu surface area. Cu dispersed homogeneously over the γ-
alumina support by using EDTA as chelating agent,resulting in a
higher surface area and higher conversion of butanol;however,Cu
aggregated on the γ-alumina support by using TEA as chelating
agent,displaying a lower surface area and lower conversion.
The dehydration dominated the reaction when the reaction
temperature was raised beyond 340℃. The dehydration acitivity
was highly dependent on the distribution of the acidic sites
over the γ-alumina support. When the surface of γ-alumina
support was covered by Cu,the acidity of the catalyst decreased
coincidentally.
|
|---|
