Processes,
Год журнала:
2023,
Номер
11(11), С. 3211 - 3211
Опубликована: Ноя. 10, 2023
Granular
and
powdery
clinoptilolite
tuff
samples
from
Beli
Plast,
Eastern
Rhodopes,
Bulgaria,
were
coated
with
metal
hydroxides
(Fe,
Al,
Fe-Mg)
by
two-step
alkalization.
The
prepared
sorbents
tested
for
As(III)
As(V)
uptake
a
modeled
water
solution
an
arsenic
concentration
of
44
μg/L.
granular
sorbent
was
used
in
the
sorption
columns
showed
high
efficiency
purification
slightly
polluted
waters.
calculated
maximum
capacity
optimal
conditions
is
32.9
μg/g.
adsorption
proceeds
according
to
Langmuir
model.
mechanism
most
likely
inner-sphere
complexation.
sorbents’
complete
regeneration
achieved
NaOH
treatment.
results
experiments
show
good
possibilities
obtaining
ranging
below
limit
detection
3.8
µg/L,
which
significantly
lower
value
than
permitted
10
μg/L
close
national
environmental
quality
standard
shallow
shows
Fe-
or
Mg,Fe-coated
sorbents.
are
highly
efficient
purifying
400
liters
initial
mg/L
either
arsenate
arsenite
per
1
kilogram
at
rate
2.4–2.0
L/h/kg.
powdered
batch
system
under
“static”
much
higher
one.
Such
more
suitable
small
quantities
arsenic.
Gels,
Год журнала:
2024,
Номер
10(6), С. 392 - 392
Опубликована: Июнь 9, 2024
Fly
ash
was
used
as
raw
material
to
prepare
zeolites
through
silicate
gels,
assisted
by
the
hydrothermal
method.
The
gels
could
be
effectively
formed
in
a
few
minutes
molten
alkali
environment.
prepared
using
these
method,
which
realizes
transformation
from
useless
materials
highly
valuable
materials.
obtained
were
applied
removal
of
ammonium
water,
achieving
highvalue
utilization
fly
ash.
synthesized
characterized
X-ray
diffraction
(XRD),
scanning
electron
microscopy
(SEM),
energy
dispersive
spectrum
(EDS),
thermogravimetric
(TG),
and
Fourier
transform
infrared
(FTIR)
spectroscopy.
study
on
adsorption
water
shows
that
is
more
line
with
pseudo
first-order
kinetics,
mainly
occurs
first
20
min.
can
reach
equilibrium
30
min,
maximum
capacity
49.1
mg/g.
has
best
performance
at
pH
=
5.
Furthermore,
within
certain
range,
an
increase
temperature
beneficial
for
ammonium.
Energy Technologies & Resource Saving,
Год журнала:
2024,
Номер
80(3), С. 156 - 185
Опубликована: Окт. 6, 2024
The
basic
data
on
the
volume
of
formation
and
composition
fly
ash,
which
is
a
product
coal
combustion
at
thermal
power
stations,
are
given.
analysis
current
state
ways
managing
ash
makes
it
possible
to
distinguish
following
main
directions:
physical-mechanical,
physical-chemical,
biological
combined
methods
handling
it,
used
in
agriculture
(use
as
fertilizers
pesticides;
chemical
land
reclamation:
regulation
structure
pH
soil);
during
earthworks
(reinforcement
weak
expansive
soils,
use
tamponage
compositions,
arrangement
embankments
dams);
road
construction
(strengthening
soil
for
lower
layers
surface;
production
asphalt,
cement-concrete
mixtures
arranging
foundations
clothing,
well
crushed
stone-sand
gravel-sand
reinforced
with
cement);
building
materials
industry
(cement,
concrete,
solutions,
geopolymers,
bricks,
blocks,
glass,
glass
ceramics,
porous
rolled
waterproofing
materials);
protective
coatings
(paints,
enamels,
enamel
shotcrete,
heat-protective
heat-insulating
coatings);
sorbents
catalysts
their
carriers;
mechanical
engineering
(abrasive,
frictional,
filtering
lubricating
materials,
soldering,
foundry
sand
forms
or
rods);
other
(pigments,
polymer
composites,
elements
sources
electric
current,
accumulators
certain
substances,
carbon
nanoparticles
(fullerenes,
nanotubes),
cosmetics
hygiene
products);
pyrometallurgical
hydrometallurgical
recovery
elements;
alloys
metal
matrix
composites;
extracting
rare
earth
elements.
Currently,
most
appropriate
disposal
either
its
direct
minimal
change
properties,
processing
minimization
new
waste,
particular
construction.
Bibl.
164,
Fig.
3.
Molecules,
Год журнала:
2024,
Номер
29(22), С. 5244 - 5244
Опубликована: Ноя. 6, 2024
Global
development
has
led
to
the
generation
of
substantial
levels
hazardous
contaminants,
including
pesticides,
which
pose
significant
environmental
risks.
Effective
elimination
these
pollutants
is
essential,
and
innovative
materials
techniques
offer
promising
solutions.
This
study
examines
modification
natural
zeolite
(clinoptilolite)
fly
ash-based
NaA
NaX
zeolites
with
hexadecyltrimethylammonium
bromide
(CTAB)
create
inexpensive
adsorbents
for
removing
2,4-dichlorophenoxyacetic
acid
(2,4-D)
herbicide
from
water.
Detailed
characterization
was
performed,
along
an
evaluation
effects
pH,
contact
time,
temperature,
initial
2,4-D
concentration
on
their
sorption
capacities.
The
modified
samples
exhibited
changes
in
elemental
composition
(e.g.,
reduced
SiO
The
powdered
sorbents
were
applied
in
a
batch
system
under
"static"
conditions
and
showed
much
higher
adsorption
capacity
than
the
granular
one.
These
type
of
are
more
suitable
for
small
quantities
water
with
high
concentration
arsenic.
possibilities
using
all
tested
methods
arsenic
removal
have
been
evaluated,
scheme
technological
process
has
proposed.
Processes,
Год журнала:
2023,
Номер
11(11), С. 3211 - 3211
Опубликована: Ноя. 10, 2023
Granular
and
powdery
clinoptilolite
tuff
samples
from
Beli
Plast,
Eastern
Rhodopes,
Bulgaria,
were
coated
with
metal
hydroxides
(Fe,
Al,
Fe-Mg)
by
two-step
alkalization.
The
prepared
sorbents
tested
for
As(III)
As(V)
uptake
a
modeled
water
solution
an
arsenic
concentration
of
44
μg/L.
granular
sorbent
was
used
in
the
sorption
columns
showed
high
efficiency
purification
slightly
polluted
waters.
calculated
maximum
capacity
optimal
conditions
is
32.9
μg/g.
adsorption
proceeds
according
to
Langmuir
model.
mechanism
most
likely
inner-sphere
complexation.
sorbents’
complete
regeneration
achieved
NaOH
treatment.
results
experiments
show
good
possibilities
obtaining
ranging
below
limit
detection
3.8
µg/L,
which
significantly
lower
value
than
permitted
10
μg/L
close
national
environmental
quality
standard
shallow
shows
Fe-
or
Mg,Fe-coated
sorbents.
are
highly
efficient
purifying
400
liters
initial
mg/L
either
arsenate
arsenite
per
1
kilogram
at
rate
2.4–2.0
L/h/kg.
powdered
batch
system
under
“static”
much
higher
one.
Such
more
suitable
small
quantities
arsenic.
