Cell Reports Physical Science,
Год журнала:
2023,
Номер
4(12), С. 101692 - 101692
Опубликована: Ноя. 20, 2023
Non-oxidative
alkane
dehydrogenation
produces
alkene
and
hydrogen
products.
The
current
processes
face
three
challenges:
limited
conversion
due
to
thermodynamics,
rapid
catalyst
deactivation,
CO2
emissions
from
process
heating.
A
membrane
reactor
(MR)
has
the
potential
overcome
thermodynamic
limit
by
removing
H2
in
situ,
but
both
tend
deactivate
quickly.
Here,
we
report
a
carbon
that
integrates
H2-permeable
molecular
sieve
(CMS)
hollow
fiber
membranes
siliceous
zeolite-supported
metal
catalysts.
By
lowering
reaction
temperature
using
catalysts
with
low
threshold
overcoming
CMS
membranes,
achieve
high
stability.
electro-conductive
nature
of
enables
joule
heating
reaction,
reducing
emissions.
We
demonstrate
record-high
stability
for
propylene
ethylene
production,
second-
first-largest-volume
chemicals
used
as
feedstock
globally.
Chemical Society Reviews,
Год журнала:
2023,
Номер
52(5), С. 1773 - 1946
Опубликована: Янв. 1, 2023
This
review
summarizes
the
use
of
zeolites
and
ordered
mesoporous
silica-based
catalysts,
development
new
processes
technologies
to
boost
conversion
CO
2
into
chemicals
fuels.
Chemical Reviews,
Год журнала:
2023,
Номер
123(9), С. 6107 - 6196
Опубликована: Март 30, 2023
The
Brønsted
acidity
of
proton-exchanged
zeolites
has
historically
led
to
the
most
impactful
applications
these
materials
in
heterogeneous
catalysis,
mainly
fields
transformations
hydrocarbons
and
oxygenates.
Unravelling
mechanisms
at
atomic
scale
been
object
tremendous
efforts
last
decades.
Such
investigations
have
extended
our
fundamental
knowledge
about
respective
roles
confinement
catalytic
properties
proton
exchanged
zeolites.
emerging
concepts
are
general
relevance
crossroad
catalysis
molecular
chemistry.
In
present
review,
emphasis
is
given
views
on
mechanism
generic
catalyzed
by
acid
sites
zeolites,
combining
information
gained
from
advanced
kinetic
analysis,
situ,
operando
spectroscopies,
quantum
chemistry
calculations.
After
reviewing
current
nature
themselves,
key
parameters
a
focus
made
reactions
undergone
alkenes,
alkanes,
aromatic
molecules,
alcohols,
polyhydroxy
molecules.
Elementary
events
C–C,
C–H,
C–O
bond
breaking
formation
core
reactions.
Outlooks
take
up
future
challenges
field,
aiming
getting
ever
more
accurate
mechanisms,
as
ultimate
goal,
provide
rational
tools
for
design
improved
zeolite-based
catalysts.
Fuel,
Год журнала:
2024,
Номер
366, С. 131270 - 131270
Опубликована: Март 1, 2024
Light
olefins
are
unsaturated
hydrocarbons
with
at
least
one
carbon–carbon
double
bond.
They
include
ethene
(or
ethylene)
propene
propylene),
and
butene.
Ethylene
propylene,
sometimes
called
the
king
crown
of
chemicals,
critical
building
blocks
in
petrochemical
industry.
Concerns
about
sustainable
development
climate
change
have
prompted
chemical
manufacturers
to
start
seeking
renewable
feedstocks.
Since
oil
reserves
finite
high
demand,
it
is
essential
look
for
an
alternative
route,
especially
a
one,
produce
light
olefins.
Demand
these
has
been
continually
increasing.
These
materials
serve
myriad
markets,
such
as
manufacture
polymers,
fibres,
numerous
organic
chemicals.
Thus,
range
applications
continues
expand
globally
across
many
industries.
Propylene,
particular,
demand
Steam
cracking
significant
route
more
than
50
years.
However,
steam
technology
requires
energy
consumption
involves
CO2
emissions
atmosphere,
Therefore,
much
attention
focused
on
developing
other
alternatives
which
energy-efficient
reduced
emission.
This
paper
effort
review
current
technologies
olefin
production.
It
covers
both
major
commercial
processes
new
use
microwaves
will
go
through
olefins,
also
considered
types
feedstock,
most
used
catalysts,
hypothesized
mechanisms
catalytic
reactions.
The
literature
mainly
last
20
years,
but
we
consider
published
century
give
broad
perspective
evolution
developments
producing
Chemical Society Reviews,
Год журнала:
2021,
Номер
51(1), С. 376 - 423
Опубликована: Дек. 14, 2021
In
the
last
few
decades,
scientists
have
been
motivated
by
promising
production
of
chemicals
from
methane
under
mild
conditions
for
low
energy
consumption
and
climate
remediation;
significant
fundamental
understanding
on
this
topic
has
achieved.
ACS Catalysis,
Год журнала:
2022,
Номер
12(9), С. 5060 - 5076
Опубликована: Апрель 14, 2022
Zeolites
and
metal-zeolites
are
a
class
of
porous
materials
that
have
been
widely
utilized
in
industry.
So
far,
several
fundamental
questions
relating
to
the
dynamic
evolution
zeolite
framework
metal-zeolite
interface
remain
unanswered.
Contrary
classical
view
zeolites
as
static,
rigid,
changeless
material,
atoms
foreign
metals
can
dynamically
interconvert
under
pretreatment
or
reaction
conditions,
making
it
difficult
identify
real
active
centers
mechanisms.
With
development
characterization
techniques
theoretical
calculations,
more
profound
understanding
at
atomic
scale
has
achieved.
This
critical
Review
will
feature
recent
progress
metal-zeolites,
mainly
focusing
on
T–O–T
bonds
breaking
formation,
metal
valence
state
transformation,
phase
evolution,
migration.
We
compare
these
proposed
mechanisms
analyze
their
suitability
distinct
experimental
conditions.
highlight
identification
sites
catalytic
mechanism
should
be
cautious
consider
Finally,
we
summarize
usages
limitations
different
characteristic
techniques,
propose
some
future
research
directions
about
hope
bridge
gaps
between
knowledge
achieved
characterizations
nature
guide
zeolite-based
synthesis,
modification,
application.
Energy & Fuels,
Год журнала:
2023,
Номер
37(3), С. 1657 - 1677
Опубликована: Янв. 19, 2023
The
price
of
light
aromatics,
which
are
important
chemical
intermediates,
is
greatly
affected
by
fluctuations
in
the
oil
market,
and
there
a
gap
supply.
It
urgent
to
expand
source
aromatics
match
market
demand.
Being
highly
accessible,
oxygen-free
aromatization
alkanes
(C1–C4),
with
high
product
selectivity
cost-effectiveness,
has
attracted
widespread
interest
from
both
academia
industry.
However,
rapid
deactivation
catalysts
due
carbon
deposition
seriously
hindered
industrialization
process.
This
Review
presents
bifaciality
coke
on
proposes
formation
mechanism
related
dynamic
migration
intermediates
according
type
catalyst
active
site.
An
emphasis
placed
creating
reaction
microenvironment
that
resists
improving
mass-transfer
efficiency,
controlling
interaction
between
sites,
adjusting
silanol
defects,
looking
forward
future
directions
for
development.
Angewandte Chemie International Edition,
Год журнала:
2023,
Номер
62(25)
Опубликована: Май 9, 2023
The
location
of
Brønsted-acid
sites
(bridging
OH
groups,
b-OH)
at
different
crystallographic
positions
zeolite
catalysts
influences
their
reactivity
due
to
varying
confinement.
Selecting
the
most
stable
b-OH
conformers
each
12
T-sites
(T=Si/Al)
H-MFI,
a
representative
set
26
is
obtained
which
includes
free
groups
pointing
into
empty
pore
space
and
forming
H-bonds
across
five-
or
six-membered
rings
TO4
tetrahedra.
Chemically
accurate
coupled-cluster-quality
calculations
for
periodic
models
show
that
strength
internal
and,
hence,
bond
length
vary
substantially
with
framework
position.
For
11
19
H-bonded
examined,
our
predictions
fall
full
width
half
maximum
range
experimental
signals
3250±175
cm-1
7.0±1.4
ppm
supports
previously
debated
assignments
these
sites.
