Journal of Colloid and Interface Science,
Journal Year:
2020,
Volume and Issue:
585, P. 337 - 346
Published: Nov. 24, 2020
Molecular
dynamics
(MD)
simulations
are
used
to
predict
the
partitioning
of
per-
and
polyfluoroalkyl
substances
(PFASs)
smectite
clay,
a
high
surface
area
adsorbent
ubiquitous
in
temperate
soils.
Simulated
systems
model
stack
flexible
lamellae
contact
with
bulk
aqueous
reservoir
containing
PFAS
molecules.
Perfluorobutanesulfonic
acid
(PFBS),
perfluorohexanesulfonic
(PFHxS),
perfluorooctanesulfonic
(PFOS)
simulated
at
various
chemistry
conditions
examine
effect
size,
salinity,
coordinating
cation
type
(K+,
Na+,
Ca2+)
on
adsorption.
The
metadynamics
technique
is
employed
facilitate
exploration
simulation
cell
reconstruct
underlying
free
energy
landscape.
Adsorption
favorable
hydrophobic
domains
external
basal
surfaces
fluorinated
chain
adopting
flat
orientation
surface.
Analysis
adsorption
energetics
reveals
large
entropic
contributions
enthalpy
unfavorable,
though
much
less
so
presence
Ca2+
due
stabilizing
'lateral
bridging'
interactions
between
divalent
cations
sulfonate
head
groups.
Overall,
this
research
advances
mechanistic
understanding
PFAS-smectite
provides
new
insights
that
could
help
inform
fate
transport
models
development
adsorbents
remediation
techniques.
Environmental Technology & Innovation,
Journal Year:
2020,
Volume and Issue:
19, P. 101026 - 101026
Published: July 1, 2020
The
levels
of
pesticides
in
water
have
increased
due
to
their
excessive
use
the
modern
agricultural
domain.
Choosing
a
suitable
treatment
method
for
pesticide
removal
depends
on
type
and
efficacy
process.
This
review
critically
discusses
provides
detailed
description
variety
chemical,
physical,
biological
approaches
from
water,
such
as
advanced
oxidation
processes,
adsorption,
activated
sludge,
membrane
bioreactors,
technologies.
Both
single-treatment
hybrid
methods
are
thoroughly
described
discussed.
techniques
offers
potential
opportunities
develop
innovative
techniques.
A
thorough
analysis
influent
composition
recognition
best
technique
is
very
important
design
plant
that
targets
maximum
possible
rate
different
types
pesticides.
Furthermore,
decentralization
was
also
discussed
which
it
an
approach
would
lead
better
effluent
quality
lower
prices.
Many
affordable
sludge
adsorption
by
adsorbents
showed
high
treating
Environmental Science & Technology Letters,
Journal Year:
2019,
Volume and Issue:
6(12), P. 688 - 695
Published: Nov. 22, 2019
Perfluoroalkyl
and
polyfluoroalkyl
substances
(PFAS)
are
a
group
of
persistent
mobile
fluoro-organic
chemicals
that
have
been
detected
in
many
water
supplies,
their
recommended
safe
concentrations
drinking
as
low
6
ng/L.
Current
technological
advances
suggest
amine-containing
sorbents
can
provide
alternative
solutions
to
PFAS
control
the
treatment
municipal
wastewater
at
relatively
concentrations.
The
objective
this
review
is
critical
analysis
development
application
for
removal.
removal
by
aminated
relies
on
combined
effects
three
main
factors:
(i)
electrostatic
interactions
with
functional
groups
sorbent,
(ii)
hydrophobic
sorbent
between
molecules,
(iii)
morphology.
design
next-generation
should
take
into
consideration
these
factors
relative
contribution.
We
also
an
outlook
highlight
key
areas
innovative
research
needs
develop
more
efficient
will
enable
compliance
increasingly
stringent
regulations
PFAS.
