ChemSusChem,
Journal Year:
2024,
Volume and Issue:
17(20)
Published: May 20, 2024
Although
the
introduction
of
plastics
has
improved
humanity's
everyday
life,
fast
accumulation
plastic
waste,
including
microplastics
and
nanoplastics,
have
created
numerous
problems
with
recent
studies
highlighting
their
involvement
in
various
aspects
our
lives.
Upcycling
plastics,
conversion
waste
to
high-added
value
chemicals,
is
a
way
combat
that
receiving
increased
attention.
Herein,
we
describe
novel
aerobic
photochemical
process
for
upcycling
real-life
polystyrene-based
into
benzoic
acid.
A
new
employing
thioxanthone-derivative,
combination
N-bromosuccinimide,
under
ambient
air
390
nm
irradiation
capable
polystyrene-derived
products
acid
yields
varying
from
24-54
%.
Cleaner Chemical Engineering,
Journal Year:
2023,
Volume and Issue:
5, P. 100094 - 100094
Published: Jan. 26, 2023
•
Hydrothermal
liquefaction
(HTL)
has
been
studied
for
plastic
recycling.
At
sub-
and
supercritical
conditions,
HTL
depolymerization
may
be
carried
out.
Subcritical
conditions
can
depolymerize
polymers
with
functional
groups.
It
is
easier
to
polyolefins
water(>
374
°C;
>
22
MPa).
Low-pressure
hydrothermal
(LP-HTL)
handle
polyolefin
hydrocarbons.
If
our
expectations
are
have
a
future
the
resources
provided
by
earth,
recycling
of
plastics
become
one
most
important
topics
that,
as
humans,
we
must
deal
with.
Among
technologies
developed
treating
this
issue
method.
In
review,
subcritical
processes
presented.
Experimental
methods
product
yields
disclosed
discussed.
previously
used
synthetic
containing
heteroatoms,
such
bisphenol-A-based
epoxy
resin
(Epoxy),
polyamide
6
(PA6),
6/6
(PA66),
polyethylene
terephthalate
(PET),
polycarbonate
(PC),
polyurethane
(PU).
This
type
polymer
broken
down
using
low-temperature,
low-pressure
method
because
it
heteroatoms
that
easy
break
down.
To
like
(PE)
polypropylene
(PP),
derivatives
mixtures,
formed
long
hydrocarbon
chains,
water
(>
23
MPa)
seem
required.
These
requirements
make
procedure
quite
expensive.
The
review
showed
new
uses
pressures
between
2.5
30
MPa,
temperatures
above
400
°C,
residence
times
20
60
min,
named
(LP-HTL),
hydrocarbon.
describes
needed
problematic
feedstock
and,
in
certain
way,
possible
utilization
technology
more
complex
waste
mixtures.
Chemical Reviews,
Journal Year:
2024,
Volume and Issue:
124(16), P. 9457 - 9579
Published: Aug. 16, 2024
The
large
production
volumes
of
commodity
polyolefins
(specifically,
polyethylene,
polypropylene,
polystyrene,
and
poly(vinyl
chloride)),
in
conjunction
with
their
low
unit
values
multitude
short-term
uses,
have
resulted
a
significant
pressing
waste
management
challenge.
Only
small
fraction
these
is
currently
mechanically
recycled,
the
rest
being
incinerated,
accumulating
landfills,
or
leaking
into
natural
environment.
Since
are
energy-rich
materials,
there
considerable
interest
recouping
some
chemical
value
while
simultaneously
motivating
more
responsible
end-of-life
management.
An
emerging
strategy
catalytic
depolymerization,
which
portion
C-C
bonds
polyolefin
backbone
broken
assistance
catalyst
and,
cases,
additional
molecule
reagents.
When
products
molecules
materials
higher
own
right,
as
feedstocks,
process
called
upcycling.
This
review
summarizes
recent
progress
for
four
major
upcycling
strategies:
hydrogenolysis,
(hydro)cracking,
tandem
processes
involving
metathesis,
selective
oxidation.
Key
considerations
include
macromolecular
reaction
mechanisms
relative
to
mechanisms,
design
transformations,
effect
conditions
on
product
selectivity.
Metrics
describing
critically
evaluated,
an
outlook
future
advances
described.
ChemSusChem,
Journal Year:
2022,
Volume and Issue:
16(2)
Published: Nov. 28, 2022
Abstract
Converting
poly(ethylene
terephthalate)
(PET)
into
metal–organic
frameworks
(MOFs)
has
emerged
as
a
promising
innovation
for
upcycling
of
waste
plastics.
However,
previous
solvothermal
methods
suffer
from
toxic
solvent
consumption,
long
reaction
time,
high
pressure,
and
temperature.
Herein,
mechanochemical
milling
strategy
was
reported
to
transform
PET
series
MOFs
with
yields.
This
had
the
merits
solvent‐free
conditions,
ambient
temperature,
short
running
easy
scale‐up
large‐scale
production
MOFs.
The
as‐prepared
exhibited
definite
crystal
structure
porous
morphology
composed
agglomerated
nanoparticles.
It
proven
that,
under
milling,
firstly
decomposed
1,4‐benzenedicarboxylate,
which
acted
linkers
coordinate
metal
ions
forming
fragments,
followed
by
gradual
arrangement
fragments
work
not
only
promotes
value‐added
conversion
polyesters
but
also
offers
new
opportunity
produce
in
green
scalable
manner.
