Journal of Water Process Engineering,
Journal Year:
2024,
Volume and Issue:
61, P. 105332 - 105332
Published: April 18, 2024
Per-
and
poly-fluoroalkyl
substances
(PFAS)
are
a
group
of
diverse
anthropogenic
chemicals
that
global
concern.
This
study
explored
degradation
perfluorooctanoic
acid
(PFOA),
its
common
alternatives,
perfluorobutanoic
(PFBA)
hexafluoropropylene
oxide
dimer
(HFPO-DA
or
GenX)
through
photochemical
processes
employing
sulfite
persulfate
mediators.
Specific
objectives
were
to
i)
assess
key
operational
parameters
their
interactions,
ii)
determine
the
roles
direct
photolysis,
generated
active
species,
UV
wavelengths,
iii)
explore
impacts
copresent
organic
inorganic
constituents,
iv)
develop
kinetic
model
for
sulfite-mediated
optical
intrinsic
rates
studied
PFAS
with
hydrated
electron
(eaq−).
Photochemical
experiments
conducted
in
well-controlled
collimated
beam
setups,
facilitating
fluence-based
study.
In
both
sulfite-
persulfate-mediated
systems,
solution
pH
is
most
significant
factor,
followed
by
mediator
concentration.
The
Φ254
nm
Φ185
0.104
±
0.007
1.38
0.11
mol/einstein,
highlighting
synergistic
impact
introducing
185
process.
Scavengers
water
matrices
influence
eaq−
SO4•–
dominating
respectively.
highlights
potential
role
O2•–
GenX
decomposition
elucidates
intermediates
evolution
mechanisms,
where
lead
distinct
CO
bond
breakage
GenX.
process
exhibits
slower
kinetics,
resulting
higher
lower
defluorination
efficiency.
Kinetic
modeling
reveals
rate
constants
PFOA,
PFBA,
as
(8.34
0.08)
×
107,
(5.85
0.07)
(1.70
0.10)
107
M−1
s−1,
