Industrial & Engineering Chemistry Research,
Journal Year:
2024,
Volume and Issue:
63(42), P. 17868 - 17877
Published: Oct. 15, 2024
In
the
pursuit
of
circular
economies
aimed
at
achieving
sustainable
development,
chemical
recycling
emerges
as
a
promising
method
for
transforming
polycarbonate
(PC)
plastic
into
value-added
monomer.
Herein,
methanol
dispersions
ultrasmall
ZnO
nanoparticles
(∼4
nm)
are
firstly
utilized
catalytic
methanolysis
PC.
Under
mild
reaction
conditions
(120
°C,
1
h)
with
low
catalyst
amount
(0.8
wt
%),
complete
conversion
PC
and
97.8%
yield
BPA
could
be
achieved.
The
above
also
capable
depolymerizing
representative
real
wastes
(DVD
disks,
CD
sheets)
least
96%,
exhibiting
excellent
prospects
industrial
application.
Furthermore,
possible
mechanism
was
proposed,
kinetics
investigated
an
activation
energy
122.39
kJ/mol.
More
importantly,
activity
can
reach
high
125
g
h–1
(g
ZnO)−1,
highest
reported
to
date.
Angewandte Chemie International Edition,
Journal Year:
2023,
Volume and Issue:
62(46)
Published: Aug. 3, 2023
To
address
the
global
plastic
pollution
issues
and
challenges
of
hydrogen
storage
transportation,
we
report
a
system,
based
on
hydrodeoxygenation
(HDO)
oxygen-containing
aromatic
wastes,
from
which
organic
carriers
(LOHCs)
can
be
derived.
We
developed
catalytic
system
comprised
Ru-ReOx
/SiO2
+HZSM-5
for
direct
HDO
polycarbonate
(PC),
polyethylene
terephthalate
(PET),
polybutylene
(PBT),
polyphenylene
oxide
(PPO),
their
mixtures,
to
cycloalkanes
as
LOHCs,
with
high
yields
up
99
%,
under
mild
reaction
conditions.
The
theoretical
capacity
reaches
ca.
5.74
wt%.
pathway
involves
depolymerization
PC
into
C15
aromatics
monophenols
by
hydrogenolysis
C-O
bond
between
benzene
ring
ester
group,
subsequent
parallel
hydrogenation
monophenols.
cyclic
alcohol
is
rate-determining
step.
active
site
Ru
metallic
nanoparticles
partially
covered
ReOx
species.
excellent
performance
attributed
synergetic
effect
oxophilic
species
sites
hydrogenation,
promotion
HZSM-5
dehydration
alcohol.
highly
efficient
stable
dehydrogenation
over
Pt/γ-Al2
O3
confirms
that
products
act
LOHCs.
Chemical Engineering Journal,
Journal Year:
2024,
Volume and Issue:
485, P. 149832 - 149832
Published: Feb. 19, 2024
In
the
pursuit
of
circular
economies
aimed
at
eliminating
waste
and
pollution,
chemical
recycling
emerges
as
a
promising
avenue
for
transforming
plastics
into
monomers.
This
study
addresses
need
economically
viable
mild
depolymerisation
methods,
focusing
on
poly(bisphenol
A
carbonate)
(BPA-PC),
an
engineering
plastic
with
monomer
bisphenol
(BPA),
known
xenoestrogen.
Improving
BPA-PC
is
crucial
to
prevent
release
BPA
environment.
Our
investigation
centres
three
commercially
available
organocatalyst-modified
silica
gels
in
polycarbonate
(PC)
methanolysis,
alongside
one
functionalised
1,5,7-triazabicyclo-[4.4.0]-dec-5-ene
(TBD),
previously
reported
polyethylene
terephthalate
(PET)
glycolysis.
The
latter
Si-TBD,
among
these
catalysts,
exhibits
superior
catalytic
activity
PC
methanolysis.
methanolysis
process
was
optimised
by
experimental
design.
Under
optimal
reaction
conditions
(PC:
2.00
g,
methanol
(n(MeOH):n(PC)
=
13:1),
Si-TBD:
5
mol%,
65
°C,
2
h),
96
%
non-isolated
yield
obtained.
kinetics
reveals
that
Si-TBD-catalysed
pseudo-first-order
exceptionally
low
activation
energy
44.19
kJ
mol−1,
lowest
date.
Si-TBD
recycled
ten
cycles
after
regeneration,
even
though
regenerated
catalyst
has
slightly
lower
than
native
catalyst,
good
yields
(72
±
4
%)
were
achieved
consistently.
Investigations
necessity
inert
atmosphere
during
indicate
it
not
required.
Impressively,
demonstrates
ability
depolymerise
room
temperature,
without
stirring,
days,
excellent
(94
%).
Notably,
this
offers
similar
performance
temperature
others
literature
ChemPlusChem,
Journal Year:
2024,
Volume and Issue:
unknown
Published: May 3, 2024
Chemical
recycling
and
upcycling
offer
promising
approaches
for
the
management
of
plastic
wastes.
Hydrodeoxygenation
(HDO)
is
one
appealing
ways
conversion
oxygen-containing
wastes,
including
polyethylene
terephthalate
(PET),
polybutylene
(PBT),
polycarbonate
(PC),
polyphenyl
ether
(PPO),
polyether
ketone
(PEEK),
into
cyclic
alkanes
aromatics
in
high
yields
under
mild
reaction
conditions.
The
challenge
lies
achieving
C-O
activation
while
preserving
C-C
bonds.
In
this
review,
we
highlight
recent
advancements
catalytic
strategies
catalysts
these
wastes
cycloalkanes
aromatics.
systems,
multi-step
routes,
direct
HDO
transfer
methods,
are
exemplified.
design
performance
systematically
summarized
compared.
We
comprehensively
discuss
functions
catalysts'
components,
pathway
mechanism
to
gain
insights
process
efficient
valorization
Finally,
provide
perspectives
field,
with
specific
emphasis
on
non-noble
metal
catalyst
design,
selectivity
control,
network
studies,
mixed
product
functionalization.
anticipate
that
review
will
inspire
innovations
development
rational
aromatic
plastics
establish
a
low-emission
circular
economy.
JACS Au,
Journal Year:
2024,
Volume and Issue:
4(11), P. 4361 - 4373
Published: Oct. 11, 2024
The
chemical
upcycling
of
plastic
wastes
by
converting
them
into
valuable
fuels
and
chemicals
represents
a
sustainable
approach
as
opposed
to
landfilling
incineration.
However,
it
encounters
challenges
in
dealing
with
mixed
due
their
complex
composition
sorting/cleaning
costs.
Here,
we
present
one-pot
hydrodeoxygenation
(HDO)
method
for
containing
poly(ethylene
terephthalate)
(PET),
polycarbonate
(PC),
poly(phenylene
oxide)
(PPO)
naphthenes
under
mild
reaction
conditions.
To
facilitate
this
process,
developed
cost-effective,
contaminant-tolerant,
reusable
Ni/HZSM-5
bifunctional
catalyst
through
an
ethylene
glycol-assisted
impregnation
method.
metallic
Ni
site
plays
pivotal
role
catalyzing
C-O
C-C
cleavages
well
hydrogenation
reactions,
while
the
acidic
HZSM-5
facilitates
dehydration
isomerization
reactions.
collaboration
between
metal
acid
dual
sites
on
enabled
efficient
HDO
wide
range
substrates,
including
bottles,
textile
fibers,
pellets,
sheets,
CDs/DVDs,
plastics
without
cleaning
or
pigments
removal
even
various
mixtures,
high
yield
up
99%
at
250
°C
4
MPa
H
Advanced Sustainable Systems,
Journal Year:
2025,
Volume and Issue:
unknown
Published: March 20, 2025
Abstract
The
unmatched
applications
of
plastic
commodities
are
evident
from
the
enormous
production,
reaching
over
400
million
tons
per
year
in
recent
times.
Contrastingly,
lack
proper
management
leads
to
a
large
accumulation
waste,
majorly
including
polyolefins
and
polyesters.
Conventional
methods
possess
significant
drawbacks
like
cost‐ineffectiveness
greenhouse
gas
emissions.
Over
last
decade,
chemical
processes
have
shown
promising
potential
for
but
only
hold
0.1%
share
recycling.
catalytic
offer
excellent
protocols
obtain
high‐value
liquid
fuels,
waxes,
chemicals
waste.
This
review
presents
an
elaborate
discussion
on
state
art
reductive
upcycling
polyolefins,
polyesters,
mixed
initially
discusses
alarming
statistics
plastics
conventional
approaches
followed
by
introduction
processes.
Further,
various
recently
reported
strategies
been
elaborated
detail
catalyst
deactivation,
technoeconomic
analysis,
life
cycle
assessment
deeper
understanding
current
this
research
field.
Finally,
detailed
summary
along
with
existing
challenges
countermeasures
is
discussed
open
new
avenues
waste
research.
