Environmental Technology,
Год журнала:
2024,
Номер
unknown, С. 1 - 14
Опубликована: Авг. 16, 2024
Red
mud
(RM)
is
the
industrial
solid
waste
produced
after
alumina
extraction
from
bauxite,
and
most
RM
directly
discharged
to
landfill
yards
without
any
treatment.
In
this
study,
modified
red
(MRM)
was
synthesized
by
a
hydrothermal
chemical
modification
method
as
an
efficient
adsorbent
for
methylene
blue
(MB)
removal.
The
prepared
MRM
characterized
X-ray
fluorescence
spectroscopy,
diffraction,
scanning
electron
microscope,
transmission
Fourier
transform
infrared
spectrometer.
effects
of
reaction
time,
initial
MB
concentrations,
dosage,
temperature,
system
pH
were
investigated
in
batch
adsorption
experiments.
results
showed
that
increased
specific
surface
area
material
16.72
414.47
m2/g.
maximum
capacity
280.18
mg/g
under
conditions
concentration
1000
mg/L,
time
300
min,
temperature
25
℃,
natural
6.06.
Meanwhile,
kinetics
equilibrium
isotherms
demonstrated
fit
well
with
pseudo-second-order
kinetic
model
Temkin
isotherm,
respectively.
This
study
provides
new
valorization
demonstrates
can
be
used
low
cost
environmentally
friendly
potential
removal
wastewater.
Nature,
Год журнала:
2024,
Номер
625(7996), С. 703 - 709
Опубликована: Янв. 24, 2024
Abstract
Red
mud
is
the
waste
of
bauxite
refinement
into
alumina,
feedstock
for
aluminium
production
1
.
With
about
180
million
tonnes
produced
per
year
,
red
has
amassed
to
one
largest
environmentally
hazardous
products,
with
staggering
amount
4
billion
accumulated
on
a
global
scale
Here
we
present
how
this
can
be
turned
valuable
and
sustainable
ironmaking
using
fossil-free
hydrogen-plasma-based
reduction,
thus
mitigating
part
steel-related
carbon
dioxide
emissions
by
making
it
available
several
hundred
green
steel.
The
process
proceeds
through
rapid
liquid-state
chemical
partitioning,
as
well
density-driven
viscosity-driven
separation
between
metal
oxides.
We
show
underlying
reactions,
pH-neutralization
processes
phase
transformations
during
surprisingly
simple
fast
reduction
method.
approach
establishes
toxic-waste
treatment
from
mitigate
greenhouse
gas
steelmaking.
Scientific Reports,
Год журнала:
2023,
Номер
13(1)
Опубликована: Май 26, 2023
Utilizing
the
red
mud
sustainably
is
now
a
challenging
issue.
Red
due
to
its
wide
production,
presence
of
some
radioactive
elements,
high
alkalinity,
and
salinity,
has
dramatic
potential
contaminate
soil
groundwater.
Notwithstanding
drawbacks,
consists
several
including
Ca,
Al,
Ti,
Si,
Fe,
in
various
mineral
forms.
In
this
study,
stepwise
leaching
was
applied
as
proper
method
separate
purify
main
valuable
elements
using
available
affordable
HCl.
The
pre-leaching
step
under
optimized
conditions
HCl
(0.2
M)
at
room
temperature
for
2
h
removed
89%
calcium
content
from
mud.
To
selectively
remove
solid
silica,
residue
treated
with
concentrated
(3.0
M,
L/S
20
mL/g)
95
°C,
resulting
dissolution
iron
aluminum
up
90%
efficiency.
After
precipitation
Fe3+
Al3+,
they
were
characterized
FT-IR,
BET,
EDS,
XRD,
SEM
TEM
monographs,
confirming
formation
nanosized
hematite
(α-Fe2O3)
mesoporous
gamma
alumina
(γ-Al2O3).
Consequently,
inexpensive
converted
into
highly
nano-sized
metal
oxides
simple,
sustainable
techniques
cheap
reagents.
Moreover,
technique
generates
lowest
amounts
waste
during
process
all
reagents
can
be
recycled
further
uses,
making
utilization.
