ACS Omega,
Год журнала:
2021,
Номер
6(19), С. 12801 - 12812
Опубликована: Май 3, 2021
The
MnxCey
binary
catalysts
with
a
three-dimensional
network
structure
were
successfully
prepared
via
polymer-assisted
deposition
method
using
ethylenediaminetetraacetic
acid
and
polyethyleneimine
as
complexing
agents.
developed
pore
could
facilitate
the
gas
diffusion
accelerate
catalytic
reaction
for
NH3
selective
reduction
(SCR).
Moreover,
addition
of
Ce
is
beneficial
exposure
active
sites
on
catalyst
surface
increases
adsorption
NO
species.
Therefore,
Mn1Ce1
exhibits
best
activity
NOx
removal
conversion
rate
97%
at
180
°C,
superior
water
resistance,
favorable
stability.
SCR
over
takes
place
through
E–R
pathway,
which
confirmed
by
in
situ
diffuse
reflectance
Fourier
transform
analysis.
This
work
explores
new
strategy
to
fabricate
multimetal
optimize
catalysts.
Chemical Reviews,
Год журнала:
2019,
Номер
119(19), С. 10916 - 10976
Опубликована: Авг. 15, 2019
Selective
catalytic
reduction
with
NH3
(NH3–SCR)
is
the
most
efficient
technology
to
reduce
emission
of
nitrogen
oxides
(NOx)
from
coal-fired
industries,
diesel
engines,
etc.
Although
V2O5–WO3(MoO3)/TiO2
and
CHA
structured
zeolite
catalysts
have
been
utilized
in
commercial
applications,
increasing
requirements
for
broad
working
temperature
window,
strong
SO2/alkali/heavy
metal-resistance,
high
hydrothermal
stability
stimulated
development
new-type
NH3–SCR
catalysts.
This
review
summarizes
latest
SCR
reaction
mechanisms
emerging
poison-resistant
beginning
subsequently
gives
a
comprehensive
overview
newly
developed
catalysts,
including
metal
oxide
ranging
VOx,
MnOx,
CeO2,
Fe2O3
CuO
based
catalysts;
acidic
compound
containing
vanadate,
phosphate
sulfate
ion
exchanged
such
as
Fe,
Cu,
Mn,
monolith
extruded,
washcoated,
metal-mesh/foam-based
The
challenges
opportunities
each
type
are
proposed
while
effective
strategies
summarized
enhancing
acidity/redox
circle
poison-resistance
through
modification,
creating
novel
nanostructures,
exposing
specific
crystalline
planes,
constructing
protective/sacrificial
sites,
Some
suggestions
given
about
future
research
directions
that
efforts
should
be
made
in.
Hopefully,
this
can
bridge
gap
between
practical
realize
their
applications
near
future.
ACS Catalysis,
Год журнала:
2022,
Номер
12(22), С. 14347 - 14375
Опубликована: Ноя. 7, 2022
As
primary
air
pollutants,
nitrogen
oxides
(NOx)
result
in
a
series
of
environmental
issues,
such
as
photochemical
smog,
acid
rain,
ozone
depletion,
and
fine
particle
pollution,
which
threaten
the
health
all
human
beings.
Selective
catalytic
reduction
with
NH3
(NH3-SCR)
is
most
powerful
technique
for
abatement
NOx.
The
development
NH3-SCR
catalysts
key
to
normal
operation
NOx
removal
systems.
currently
used
V2O5-WO3(MoO3)/TiO2
are
widely
applicable
medium-/high-temperature
conditions
but
not
suitable
operated
at
low
temperatures.
high-efficiency
low-temperature
SCR
central
issue
present.
rational
design
efficient
requires
an
atomic-level
understanding
their
mode
operation,
including
identification
characterization
active
sites,
reaction
paths,
rate-determining
steps
NH3-SCR.
Herein,
we
summarize
recent
advances
intermediates,
pathways
oxide
molecular
sieve
mainly
studied
by
researchers
will
be
reviewed,
particular
focus
on
mechanism.
We
provide
current
general
mechanism
further
combine
guidelines
catalysts.
hope
that
our
account
trigger
research
activities
discussions
catalysis
bridge
material
gap
between
idealized
real
ACS Catalysis,
Год журнала:
2021,
Номер
11(24), С. 14727 - 14739
Опубликована: Ноя. 23, 2021
Alkali
metal
poisoning
has
been
a
complex
yet
unresolved
issue
restricting
the
catalytic
activity
of
NH3–SCR
catalysts
in
industry
to
date.
Herein,
effect
K
deposition
on
Fe/beta
for
NOx
was
systematically
investigated
by
series
experimental
characterizations
and
density
functional
theory
(DFT)
calculations.
It
determined
that
lower
could
activate
facilitate
transfer
electrons
enhance
ratio
Fe2+/Fe3+
reducible
Fe
species,
thereafter
promoting
NO
O2
adsorption
decreasing
activation
energy
NO2,
thereby
significantly
improving
0.25%
K–Fe/Beta.
To
best
our
knowledge,
this
phenomenon
not
reported
field
exhaust
abatement.
Nevertheless,
excessive
(≥0.50%)
can
only
occupy
Brönsted
acid
sites,
leading
perceptible
aggregation
active
species
an
increase
oxidation
Lewis
but
also
induce
generation
inactive
nitrates,
blocking
pore
structure
Beta
molecular
sieve,
resulting
distinctive
reduction
seriously
performances
0.50%
K–Fe/beta
1.0%
catalysts.
Thus,
study
may
shine
light
deep
understanding
alkali
poison
during
design
advanced
heterogeneous
catalysis
future.
ACS Catalysis,
Год журнала:
2021,
Номер
11(12), С. 7371 - 7382
Опубликована: Июнь 7, 2021
Zeolite-supported
metal
catalysts
are
widely
employed
in
a
number
of
chemical
processes,
and
the
stability
catalytically
active
species
is
one
most
critical
factors
determining
reaction
performance.
A
good
example
Pd/zeolite
catalyst,
which
provides
high
activity
for
methane
oxidation
but
deactivates
rapidly
under
conditions
due
to
palladium
nanoparticle
sintering.
Although
coating
metals
with
thin
shells
porous
materials
promising
strategy
address
sintering
metals,
it
still
challenging
fix
small
particles
completely
inside
zeolite
crystals.
Here,
using
an
amine-based
ligand
stabilize
during
synthesis,
we
realize
exclusive
encapsulation
highly
dispersed
oxide
clusters
(1.8–2.8
nm)
microporous
channels
voids
nanosized
silicalite-1
The
synthesis
zeolite-supported
catalyst
influence
degree
size
distribution
particles.
Thanks
effect
clusters,
together
inherent
properties
such
as
low
acidity,
hydrophobicity,
hydrothermal
stability,
optimized
Pd@silicalite-1
outperforms
traditional
Pd-based
prepared
by
wetness
impregnation,
exhibiting
both
better
lean
reaction.
