Environmental Science and Ecotechnology,
Год журнала:
2024,
Номер
21, С. 100417 - 100417
Опубликована: Март 21, 2024
Zero
Valent
Iron
(ZVI),
an
ideal
reductant
treating
persistent
pollutants,
is
hampered
by
issues
like
corrosion,
passivation,
and
suboptimal
utilization.
Recent
advancements
in
nonmetallic
modified
ZVI
(NM-ZVI)
show
promising
potential
circumventing
these
challenges
modifying
ZVI's
surface
internal
physicochemical
properties.
Despite
its
promise,
a
thorough
synthesis
of
research
this
domain
remains
elusive.
Here
we
review
the
innovative
methodologies,
regulatory
principles,
reduction-centric
mechanisms
underpinning
NM-ZVI's
effectiveness
against
two
prevalent
pollutants:
halogenated
organic
compounds
heavy
metals.
We
start
evaluating
different
modification
techniques,
such
as
liquid-phase
reduction,
mechanical
ball
milling,
pyrolysis,
their
respective
advantages.
The
discussion
progresses
towards
critical
analysis
current
strategies
used
for
NM-ZVI
to
enhance
reactivity,
electron
selectivity,
utilization
efficiency.
This
achieved
optimizing
elemental
compositions,
content
ratios,
lattice
constants,
hydrophobicity,
conductivity.
Furthermore,
propose
novel
approaches
augmenting
capability
address
complex
pollution
challenges.
highlights
alternative
remediate
water
environments
contaminated
with
or
metals,
contributing
broader
discourse
on
green
remediation
technologies.
Environmental Science & Technology,
Год журнала:
2024,
Номер
58(5), С. 2542 - 2553
Опубликована: Янв. 23, 2024
Defluorination
is
essential
to
eliminate
the
antibiotic
resistance
and
detrimental
effects
of
florfenicol
(C12H14Cl2FNO4S,
FF),
which
achievable
by
sulfidated
nanoscale
zerovalent
iron
(S-nZVI),
yet
a
comprehensive
understanding
mechanism
lacking.
Herein,
we
used
experimental
data
density
functional
theory
calculations
demonstrate
four
dechlorination-promoted
defluorination
pathways
FF,
depending
on
S-nZVI
or
not.
FF
was
defluorinated
in
rapid
then
slow
but
continuous
manner,
accompanying
consecutive
dechlorination
deschloro
(dFF)
dideschloro
(ddFF).
Unexpectedly,
predominant
occurs
spontaneous
hydrolysis
ddFF
form
hydrolyzed
byproduct
(HO-ddFF),
i.e.,
independent
S-nZVI,
initiated
intramolecular
attack
from
carbonyl
O
alkyl
F
thus
limited
for
dFF
owing
diminished
nucleophilicity
electron-withdrawing
Cl.
The
removal
Cl
also
makes
reductive
amenable.
other
two
minor
more
occur
synergy
with
dFF,
are
mediated
reactive
carbanion
intermediates
generate
HO-dFF
HO-ddFF,
respectively.
reliability
these
dechlorination-facilitated
verified
consistency
theoretical
data,
providing
valuable
insights
into
degradation
fluorinated
contaminants.
Environmental Science & Technology,
Год журнала:
2024,
Номер
58(25), С. 11193 - 11202
Опубликована: Июнь 11, 2024
Per-
and
poly
fluoroalkyl
substances
(PFASs)
are
often
encountered
with
nonaqueous
phase
liquid
(NAPL)
in
the
groundwater
at
fire-fighting
military
training
sites.
However,
it
is
unclear
how
PFASs
affect
dechlorination
performance
of
sulfidized
nanoscale
zerovalent
iron
(S-nFe0),
which
an
emerging
promising
NAPL
remediation
agent.
Here,
S-nFe0
synthesized
controllable
S
speciation
(FeS
or
FeS2)
were
characterized
to
assess
their
interactions
for
trichloroethylene
(TCE-NAPL).
Surface-adsorbed
blocked
materials'
reactive
sites
inhibited
aqueous
TCE
dechlorination.
In
contrast,
PFASs-adsorbed
particles
improved
hydrophobicity
tended
enrich
NAPL–water
interface,
re-exposed
after
accumulation
into
accelerate
This
PFASs-induced
phenomenon
allowed
materials
present
a
higher
reactivity
(up
1.8-fold)
high
electron
efficiency
99%)
TCE-NAPL
Moreover,
nFe0-FeS2
was
more
readily
enriched
interface
selective
than
nFe0-FeS,
regardless
coexisting
PFASs.
These
results
unveil
that
small
amount
yet
previously
overlooked
can
favor
reductions
by
S-nFe0,
highlighting
importance
transportation
induced
remediation.
Environmental Science and Ecotechnology,
Год журнала:
2024,
Номер
21, С. 100417 - 100417
Опубликована: Март 21, 2024
Zero
Valent
Iron
(ZVI),
an
ideal
reductant
treating
persistent
pollutants,
is
hampered
by
issues
like
corrosion,
passivation,
and
suboptimal
utilization.
Recent
advancements
in
nonmetallic
modified
ZVI
(NM-ZVI)
show
promising
potential
circumventing
these
challenges
modifying
ZVI's
surface
internal
physicochemical
properties.
Despite
its
promise,
a
thorough
synthesis
of
research
this
domain
remains
elusive.
Here
we
review
the
innovative
methodologies,
regulatory
principles,
reduction-centric
mechanisms
underpinning
NM-ZVI's
effectiveness
against
two
prevalent
pollutants:
halogenated
organic
compounds
heavy
metals.
We
start
evaluating
different
modification
techniques,
such
as
liquid-phase
reduction,
mechanical
ball
milling,
pyrolysis,
their
respective
advantages.
The
discussion
progresses
towards
critical
analysis
current
strategies
used
for
NM-ZVI
to
enhance
reactivity,
electron
selectivity,
utilization
efficiency.
This
achieved
optimizing
elemental
compositions,
content
ratios,
lattice
constants,
hydrophobicity,
conductivity.
Furthermore,
propose
novel
approaches
augmenting
capability
address
complex
pollution
challenges.
highlights
alternative
remediate
water
environments
contaminated
with
or
metals,
contributing
broader
discourse
on
green
remediation
technologies.
