ACS Catalysis,
Год журнала:
2021,
Номер
11(15), С. 9729 - 9737
Опубликована: Июль 19, 2021
The
proximity
of
the
oxide-zeolite
bifunctional
catalysts
plays
a
crucial
role
in
syngas
conversion
to
light
olefins.
However,
its
underlying
mechanism
is
not
well
understood
and
optimal
yet
be
identified.
Herein,
we
take
ZnCrOx-SAPO-34
MnOx-SAPO-34
as
examples
show
that
reaction
benefits
from
shortened
with
granules
decreasing
micrometer
size
due
reduced
mass
transport
limitation.
CO
reaches
60.0%,
olefin
selectivity
75.5%,
space
time
yield
olefins
0.24
g·gcat–1·h–1
over
ZnCrOx-SAPO-34.
at
nanoscale
proximity,
an
interaction
may
develop
between
different
active
sites
migration
metal
species
addition
intermediate
exchange,
which
could
modify
their
properties
significantly.
For
instance,
zinc
migrate
SAPO-34
form
Zn-OH
preferably
Brønsted
acid
under
conditions,
leads
deteriorating
enhanced
hydrogenation.
This
can
alleviated
zeotypes
containing
less
sites.
By
contrast,
MnOx
does
exhibits
feature
"the
closer,
better"
MnOx-SAPO-34.
These
findings
are
essential
for
further
development
analogous
catalysts.
Transactions of Tianjin University,
Год журнала:
2022,
Номер
28(4), С. 245 - 264
Опубликована: Авг. 1, 2022
Abstract
Catalytic
conversion
of
CO
2
into
chemicals
and
fuels
is
a
viable
method
to
reduce
carbon
emissions
achieve
neutrality.
Through
thermal
catalysis,
electrocatalysis,
photo(electro)catalysis,
can
be
converted
wide
range
valuable
products,
including
CO,
formic
acid,
methanol,
methane,
ethanol,
acetic
propanol,
light
olefins,
aromatics,
gasoline,
as
well
fine
chemicals.
In
this
mini-review,
we
summarize
the
recent
progress
in
heterogeneous
catalysis
for
highlight
some
representative
studies
different
routes.
The
structure–performance
correlations
typical
catalytic
materials
used
reactions
have
been
revealed
by
combining
advanced
situ/operando
spectroscopy
microscopy
characterizations
density
functional
theory
calculations.
selectivity
toward
single
reduction
product/fraction
should
further
improved
at
an
industrially
relevant
rate
with
considerable
stability
future.
Graphical
Accounts of Chemical Research,
Год журнала:
2024,
Номер
57(5), С. 714 - 725
Опубликована: Фев. 13, 2024
ConspectusThe
hydrogenative
conversion
of
both
CO
and
CO2
into
high-value
multicarbon
(C2+)
compounds,
such
as
olefins,
aromatic
hydrocarbons,
ethanol,
liquid
fuels,
has
attracted
much
recent
attention.
The
hydrogenation
is
related
to
the
chemical
utilization
various
carbon
resources
including
shale
gas,
biomass,
coal,
carbon-containing
wastes
via
syngas
(a
mixture
H2
CO),
while
by
green
chemicals
fuels
would
contribute
recycling
for
neutrality.
state-of-the-art
technologies
CO/CO2
C2+
compounds
primarily
rely
on
a
direct
route
Fischer–Tropsch
(FT)
synthesis
an
indirect
two
methanol-mediated
processes,
i.e.,
methanol
from
compounds.
be
more
energy-
cost-efficient
owing
reduced
operation
units,
but
product
selectivity
FT
limited
Anderson–Schulz–Flory
(ASF)
distribution.
Selectivity
control
compound
one
most
challenging
goals
in
field
C1
chemistry,
chemistry
transformation
one-carbon
(C1)
molecules.We
have
developed
relay-catalysis
strategy
solve
challenge
arising
complicated
reaction
network
involving
multiple
intermediates
channels,
which
inevitably
lead
side
reactions
byproducts
over
conventional
heterogeneous
catalyst.
core
relay
catalysis
design
single
tandem-reaction
channel,
can
target
controllably,
choosing
appropriate
(or
intermediate
products)
steps
connecting
these
intermediates,
arranging
optimized
yet
matched
catalysts
implement
like
relay.
This
Account
showcases
representative
systems
our
group
past
decade
lower
(C2–C4)
aromatics,
oxygenates
with
breaking
limitation
catalysts.
These
are
typically
composed
metal
or
oxide
CO/CO2/H2
activation
zeolite
C–C
coupling
reconstruction,
well
third
even
fourth
catalyst
component
other
functions
if
necessary.
mechanisms
oxides,
distinct
that
transition
noble
surfaces,
discussed
emphasis
role
oxygen
vacancies.
Zeolites
catalyze
(including
hydrocracking/isomerization
heavier
methanol-to-hydrocarbon
reactions,
carbonylation
methanol/dimethyl
ether)
system,
mainly
controlled
Brønsted
acidity
shape-selectivity
confinement
effect
zeolites.
We
demonstrate
thermodynamic/kinetic
matching
steps,
proximity
spatial
arrangement
components,
transportation
intermediates/products
sequence
key
issues
guiding
selection
each
construction
efficient
system.
Our
methodology
also
useful
molecules
coupling,
inspiring
efforts
toward
precision
catalysis.
ACS Catalysis,
Год журнала:
2024,
Номер
14(13), С. 9887 - 9900
Опубликована: Июнь 18, 2024
Oxygen
vacancies
(Ov)
in
reducible
metal
oxides
are
the
vital
active
sites
for
methanol
synthesis
via
a
CO2
hydrogenation
technology.
However,
relationship
between
density
of
Ov
and
performance
is
still
ambiguous,
it
shows
lack
versatile
strategy
to
precisely
tailor
number
Ov.
In
this
study,
with
In2O3
as
representatively
catalytic
component,
functional
theory
computation
confirms
that
property,
especially
density,
pivotal
enhancing
selectivity
by
suppressing
undesirable
reverse
water–gas
shift
reaction
CO
formation,
which
attributed
unique
electronic
atoms
around
To
verify
theoretical
results,
we
report
protocol
optimize
concentration
on
sequential
carbonization
oxidation
(SCO)
treatments
In-based
metal–organic
frameworks,
during
consumption
carbon
species
structural
reconstruction
crystal
regulated
particle
size
varying
temperature.
The
In2O3-5
catalyst
carbonized
oxidized
at
500
°C
exhibits
good
(72.3%)
conversion
9.9%
under
330
°C,
3
MPa,
high
space
velocity
12,000
L–1
kgcat–1
h–1.
Multiple
situ
characterizations
clarify
proposed
property
regulating
SCO
convenient
boost
altering
process
HCOO*
intermediate-dominated
pathway.
Our
work
provides
design
will
shed
light
rational
oxide-based
catalysts
controllable
density.
