This
article
discusses
the
challenges
and
potential
solutions
for
managing
wastewater
sludge
that
contains
per-
polyfluoroalkyl
substances
(PFAS),
using
experience
in
Maine
as
a
guide
toward
addressing
issue
nationally.
Traditional
treatment,
designed
to
remove
excess
organic
waste
nutrients,
does
not
eliminate
persistent
toxic
pollutants
like
PFAS,
instead
partitioning
chemicals
between
discharged
effluent
remaining
solids
sludge.
PFAS
chemistry,
molecular
size,
alkyl
chain
length,
fluorine
saturation,
charge
of
head
group,
composition
surrounding
matrix
influence
soil
water.
Land
application
sludge,
incineration,
storage
landfill
are
traditional
management
options.
Class
B
on
agricultural
fields
peaked
1990s,
totaling
over
2
×
106
cu
yd
40-year
period
has
contaminated
certain
food
crops
animal
forage,
posing
threat
supply
environment.
Additional
A
EQ
(Exceptional
Quality)
composted
was
also
applied
farmland.
The
State
banned
land
August
2022.
Most
sent
state-owned
Juniper
Ridge
Landfill,
which
accepted
94
270
tons
dewatered
2022,
14%
increase
2019.
Between
2019
sum
perfluorooctane
sulfonate
(PFOS)
perfluorooctanoic
acid
(PFOA)
concentrations
ranged
from
1.2
104.9
ng/g
dw.
In
generated
71.6
l
leachate.
concentration
six
leachate
increased
sixfold
2021
reaching
441
ng/l.
retention
within
solid-waste
landfills
long-term
release
through
liners
into
groundwater
require
ongoing
monitoring.
Thermal
or
pyrolysis
can
theoretically
mineralize
at
high
temperatures,
yet
strong
C-F
bond
reactivity
extreme
temperatures
complete
mineralization.
Future
alternatives
may
include
interim
options
such
preconditioning
with
nonpolar
solvents
prior
immobilization
landfills,
removing
leachate,
interrupting
cycle
moving
landfill,
via
then
back
Long-term
involve
destructive
technologies
electron
beam
irradiation,
electrochemical
advanced
oxidation,
hydrothermal
liquefaction.
highlights
need
innovative
sustainable
PFAS-contaminated
Chinese Journal of Chemistry,
Год журнала:
2024,
Номер
42(16), С. 1913 - 1928
Опубликована: Апрель 24, 2024
Comprehensive
Summary
Organic
fluorine
compounds
are
ubiquitous
and
pivotally
important
organic
molecules,
yet
their
activation
transformation
have
long
been
a
formidable
challenge
due
to
the
high
energy
low
reactivity
of
C—F
bonds.
electrosynthesis,
an
environmentally
benign
synthetic
method
in
chemistry,
enables
myriad
chemical
transformations
without
need
for
external
redox
reagents.
In
recent
years,
electrochemistry
has
emerged
as
powerful
tool
achieving
bonds
fluorine‐containing
compounds.
This
review
aims
succinctly
recapitulate
latest
advancements
electrochemical
defluorinative
delve
into
reaction
design,
mechanistic
insights,
developmental
prospects
these
methods.
Key
Scientists
1959,
Lund
was
first
pioneer
electroreduction
CF
3
CH
group.
Electrochemistry
lately
provided
new
opportunities
efficient
conversion
fluorides.
2020,
Zhou
coworkers
discovered
carboxylation
α‐CF
alkenes.
Lambert
colleagues
reported
electrophotocatalytic
amination
aryl
Electrochemical
hydrodefluorination
trifluoromethylketones
developed
by
Lennox
2021.
same
year,
Wang
Guo
disclosed
radical
alkylation
alkenes
with
Katritzky
salts
alkyl
precursors.
Subsequently,
Wu
Liao
described
transition‐metal‐free,
site‐selective
arylation
polyfluoroarenes
(het)arenes
using
paired
electrophotocatalysis.
2023,
numerous
efforts
were
made
achieve
bond
activation.
Xia
organoboron‐controlled
chemoselective
sequential
(deutero)hydrodefluorination
trifluoroacetamides.
Journal of the American Chemical Society,
Год журнала:
2024,
Номер
146(15), С. 10687 - 10698
Опубликована: Апрель 5, 2024
Perfluorooctanoic
acid
(PFOA)
is
an
artificial
chemical
of
global
concern
due
to
its
high
environmental
persistence
and
potential
human
health
risk.
Electrochemical
methods
are
promising
technologies
for
water
treatment
because
they
efficient,
cheap,
scalable.
The
electrochemical
reduction
PFOA
one
the
current
methodologies.
This
process
leads
defluorination
carbon
chain
hydrogenated
products.
Here,
we
describe
a
mechanistic
study
in
gold
electrodes.
By
using
linear
sweep
voltammetry
(LSV),
E0′
−1.80
V
vs
Ag/AgCl
was
estimated.
Using
scan
rate
diagnosis,
determined
electron-transfer
coefficient
(αexp)
0.37,
corresponding
concerted
mechanism.
strong
adsorption
into
surface
confirmed
by
Langmuir-like
isotherm
absence
(KA
=
1.89
×
1012
cm3
mol–1)
presence
negative
3.94
107
mol–1,
at
−1.40
Ag/AgCl).
Based
on
Marcus–Hush's
theory,
calculations
show
solvent
reorganization
energy
(λ0)
0.9
eV,
suggesting
large
electrostatic
repulsion
between
perfluorinated
water.
estimated
free
transition
state
electron
transfer
(ΔG‡
2.42
eV)
suggests
that
it
thermodynamically
reaction-limiting
step.
19F
–
1H
NMR,
UV–vis,
mass
spectrometry
studies
confirm
displacement
fluorine
atoms
hydrogen.
Density
functional
theory
(DFT)
also
support
mechanism
reductive
PFOA,
agreement
with
experimental
values.
RSC Advances,
Год журнала:
2025,
Номер
15(11), С. 8287 - 8292
Опубликована: Янв. 1, 2025
We
demonstrate
complete
photo-assisted
electrocatalytic
defluorination
of
PFAS
in
AFFF
using
nonprecious
materials.
High-salt
LiOH
electrolyte
prevents
foaming,
and
pulsed
electrolysis
with
tailored
potential
modulation
optimizes
defluorination.
