Advanced Science,
Journal Year:
2024,
Volume and Issue:
unknown
Published: Dec. 6, 2024
Abstract
Catalytic
cracking
of
polyolefin
wastes
into
valuable
chemicals
at
mild
conditions
using
non‐noble
metal
catalysts
is
highly
attractive
yet
challenging.
Herein
it
reported
that
2D
tungsten
trioxide
(2D
WO
3
)
nanosheets,
after
decorating
with
group
VIII
promoters
(i.e.,
Fe,
Co,
or
Ni),
convert
high‐density
polyethylene
(HDPE)
alkylaromatics
and
olefins
low
temperature
ambient
pressure
without
any
solvent
hydrogen:
Ni/WO
abundant
Brønsted
acidic
sites
initiates
HDPE
a
240
°C;
Fe/WO
energy
barrier
cyclization
achieves
high
conversion
to
84.2%
liquid
hydrocarbons
selectivity
30.9%
aromatics
300
°C.
In‐situ
spectroscopic
investigations
supplementary
theoretical
calculations
illustrate
these
are
formed
through
the
alkene
intermediates.
These
also
display
efficiency
in
low‐temperature
single‐use
commercial
such
as
packaging
bags
bottles.
This
work
has
demonstrated
potential
efficient
upcycling
waste
conditions.
Energy & Fuels,
Journal Year:
2024,
Volume and Issue:
38(13), P. 11363 - 11390
Published: June 13, 2024
Pyrolysis
is
an
important
process
to
mitigate
the
issues
of
plastic
waste
accumulation
and
fossil
energy
resource
exhaustion
as
it
can
convert
into
value-added
chemicals.
Accordingly,
in
this
comprehensive
review,
pyrolysis
mechanisms
product
distributions
common
plastics,
such
polystyrene,
polyethylene,
poly(ethylene
terephthalate)
polypropylene,
poly(vinyl
chloride),
their
blends
are
examined,
inherent
properties
these
plastics
analyzed.
This
review
primarily
focuses
on
recent
advancements
catalytic
pyrolysis,
specifically
transformation
aromatics.
Additionally,
detailed
descriptions
intricate
connections
between
resulting
products
various
reaction
conditions,
including
reactor
type,
catalyst,
temperature,
provided.
Furthermore,
mechanistic
kinetic
studies
systematically
evaluated.
Finally,
challenges
prospective
trends
summarized.
offers
insights
that
serve
references
for
development
industrially
applicable
catalysts
recycling
systems.
Giant,
Journal Year:
2024,
Volume and Issue:
19, P. 100307 - 100307
Published: June 14, 2024
Polyolefins
are
the
most
produced
and
widely
used
polymeric
materials.
However,
chemically
inert
nature
of
polyolefins
has
led
to
severe
environmental
pollution,
posing
a
threat
human
sustenance
development.
Managing
recycling
polyolefin
plastic
waste
is
crucial
for
transition
from
linear
sustainable
circular
economy.
Catalytic
chemical
includes
traditional
techniques
like
pyrolysis
photolysis,
innovative
methods
that
introduce
cleavable
bonds
into
chain
closed-loop
recycling.
post-functionalization
post-consumer
materials
another
strategy
tackle
waste,
aiming
upgrade
materials'
utility
contribute
sustainability.
Overall,
developing
catalytic
deconstructing
upcycling
plastics
essential
encourage
better
reclamation
practices
reduce
impact
waste.
The Journal of Physical Chemistry C,
Journal Year:
2025,
Volume and Issue:
unknown
Published: Jan. 10, 2025
Plastic
waste
is
a
major
environmental
issue;
converting
it
directly
into
valuable
chemicals
by
using
catalysts
promising
alternative
to
plastic
recycling.
Here,
we
report
the
selective
catalytic
cracking
of
polypropylene
(PP),
typical
commodity
plastic,
high-value
light
olefins
(C2–C5),
below
pyrolytic
temperature
(290
°C)
and
without
external
hydrogen
supply,
zeolite
catalysts.
Among
H+-form
zeolites
with
different
structures,
HMFI
showed
highest
yields
hydrocarbons
which
(C2–C5)
were
products.
The
HMFI-catalyzed
PP
conversion
was
applicable
upcycling
model
waste,
resulting
in
61.9%
hydrocarbon
yield.
results
situ
IR
experiments
small
amount
Brønsted
acid
sites
suggested
that
on
surface
are
indispensable
for
posited
be
active
short-chain
(oligomeric)
species
as
intermediate
Density
functional
theory
analyses
conducted
determine
plausible
reaction
pathways
adopting
2,4-dimethylheptene
shortest
unit
oligomeric
species.
obtained
show
β-scission
isobutene
propylene
(or
propyl
alkoxide
group)
via
carbocation
intermediates
an
activation
energy
118
kJ
mol–1.
Operando
UV–vis
under
conditions,
combined
ex
1H
NMR
13C
spent
catalyst,
some
further
converted
or
heavy
aromatics
(coke
deposit),
probably
carbenium
ion
ACS Catalysis,
Journal Year:
2024,
Volume and Issue:
14(21), P. 16148 - 16165
Published: Oct. 17, 2024
Hydrocracking
of
plastics
over
bifunctional
hierarchical
zeolites
is
promising
for
the
upcycling
into
value-added
products.
However,
exact
role
their
acidic
and
textural
properties
toward
catalytic
activity
remains
unclear.
Herein,
we
modified
structure
a
β
zeolite
via
dealumination
desilication
routes,
resulting
in
zeolites.
The
parent
samples
were
loaded
with
Ni
studied
hydrocracking
virgin
HDPE.
In
comparison
to
dealuminated
zeolite,
desilicated
showed
higher
conversion
87.8%
66.7%
products
gasoline
range,
owing
its
significantly
high
properties.
selectivity
gasoline-range
hydrocarbons
further
improved
95.9
69.2%,
respectively,
by
addition.
To
unlock
structure–activity
correlation
various
samples,
different
activity-driven
factors
was
studied,
an
empirical
relationship
that
aligns
observed
conversions
samples.
Moreover,
it
possible
achieve
iso-paraffins
optimization
balance
between
metal-acid
sites
on
Furthermore,
both
Ni-loaded
good
stability
ability
be
regenerated
under
cyclic
runs.
best-performing
also
maintained
postconsumer
waste
(conversion
=
85–95%)
when
using
mixture
(88.4%).
A
life
cycle
assessment
recent
literature
demonstrated
advantages
proposed
modification
routes
achieving
productivity
(6.6–7.6
ggasoline/gcat·h)
less
environmental
impact.
Overall,
these
findings
highlight
noble-metal-free,
easily
modifiable,
environmentally
friendly
enhanced
liquid
fuels.
