PtSn/Al2O3
and
PtSnSr/Al2O3
were
prepared
by
the
incipient
wetness
impregnation
method.
The
added
Sn
Sr
are
uniformly
distributed
on
surface
without
damaging
original
crystal
structure
texture
properties.
addition
of
not
only
changes
dispersion
Pt,
reduces
reduction
temperature
but
also
provides
electrons
to
increases
electron
cloud
density
deep
propylene
adsorption.
number
total
acid
sites
strong
sites,
generation
adverse
effects
carbon
deposition,
slows
down
deactivation
catalyst,
improves
selectivity
propylene.
Pt1.5Sn1.5Sr/Al2O3
showed
best
catalytic
reaction
performance
remained
stable
after
five
cycles
regeneration.
Abstract
The
effect
of
La‐deficiency
and
Ce/Sr‐substitution
in
the
benchmark
LaCo
0.8
Fe
0.2
O
3
has
been
investigated
for
decomposition
N
2
between
500
900
°C.
Real
inlet
gas
composition
space
velocity
reveal
that
can
improve
thermal
stability
catalyst,
while
La
1‐
x
Sr
Co
with
≥0.1
was
highlighted
as
a
promising
formula
due
to
strongest
resistance
deactivation
suppressed
undesired
NO
at
high
velocity.
This
phenomenon
is
mainly
ascribed
incorporation
2+
into
perovskite
lattice
during
reaction
consequently
stabilizing
3+
species
creating
oxygen
vacancies
CoO
3‐δ
.
On
contrary,
loss
activity
on
Ce‐substituted
preferentially
related
cobalt
exsolution
extra
framework
making
catalytic
cycle
unfavorable.
All
these
bulk
surface
changes
are
accompanied
opposite
evolution
apparent
activation
energy
pre‐exponential
factor
which
be
discussed
based
redox
mechanism.
The Canadian Journal of Chemical Engineering,
Год журнала:
2024,
Номер
unknown
Опубликована: Ноя. 26, 2024
Abstract
Propane
dehydrogenation
(PDH)
has
become
a
significant
method
for
propylene
production.
However,
the
systematic
effects
of
catalyst
acidity
on
performance
remain
unclear.
In
this
study,
Pt‐based
catalysts
with
different
acidities
were
prepared
using
n‐nonane
modification,
and
their
was
evaluated
compared.
The
synergistic
interactions
between
catalyst's
its
metallic
functionality
thoroughly
investigated.
results
demonstrate
that
relationship
PDH
catalyst,
selectivity
propylene,
coke
deposition
follows
volcano‐shaped
curve.
An
optimal
exists
allows
to
achieve
efficient
performance.
Specifically,
desorption
target
product,
necessitates
combined
action
acidic
sites.
Excessive
sites
affect
sites,
while
insufficient
This
study
provides
theoretical
guidance
design
systems.
Industrial & Engineering Chemistry Research,
Год журнала:
2024,
Номер
unknown
Опубликована: Дек. 19, 2024
Maintaining
high
dispersion
of
Pt
in
catalysts
remains
a
significant
challenge
due
to
migration
and
aggregation.
Addressing
this
gap
is
critical
for
advancing
the
design
with
enhanced
performance
stability,
particularly
applications
requiring
strong
metal–support
interactions.
Here,
we
introduce
novel
catalyst
preparation
method
that
employs
an
ethylenediaminetetraacetic
acid
disodium
salt
(EDTA)
as
directing
agent
stabilize
on
Al2O3
support
promoted
by
Sn.
Leveraging
ability
EDTA
selectively
bind
Sn,
synthesized
highly
dispersed
Pt–Sn–Al2O3
dehydrogenation
catalyst.
First-principles
calculations
based
density
functional
theory
confirmed
carbonyl
hydroxyl
oxygen
atoms
preferentially
bond
Sn
support,
facilitating
precise
anchoring.
Experimental
results
further
validated
these
findings,
showing
EDTA-guided
synthesis
formation
active
sites
led
stronger
interactions,
resulting
uniform
particle
distribution
improved
stability.
This
approach
not
only
increased
propylene
selectivity
from
about
85%
93%
but
also
significantly
reduced
methane
byproduct
formation.
These
findings
demonstrate
introduction
can
effectively
address
aggregation
issues,
offering
promising
strategy
designing
more
efficient
stable
industrial
processes.
PtSn/Al2O3
and
PtSnSr/Al2O3
were
prepared
by
the
incipient
wetness
impregnation
method.
The
added
Sn
Sr
are
uniformly
distributed
on
surface
without
damaging
original
crystal
structure
texture
properties.
addition
of
not
only
changes
dispersion
Pt,
reduces
reduction
temperature
but
also
provides
electrons
to
increases
electron
cloud
density
deep
propylene
adsorption.
number
total
acid
sites
strong
sites,
generation
adverse
effects
carbon
deposition,
slows
down
deactivation
catalyst,
improves
selectivity
propylene.
Pt1.5Sn1.5Sr/Al2O3
showed
best
catalytic
reaction
performance
remained
stable
after
five
cycles
regeneration.
