Application of multiwall carbon nanotubes impregnated with 5-dodecylsalicylaldoxime for on-line copper preconcentration and determination in water samples by flame atomic absorption spectrometry
Application of multiwall carbon nanotubes impregnated with 5-dodecylsalicylaldoxime for on-line copper preconcentration and determination in water samples by flame atomic absorption spectrometry
Application of multiwall carbon nanotubes impregnated with 5-dodecylsalicylaldoxime for on-line copper preconcentration and determination in water samples by flame atomic absorption spectrometry
author:
Telk Anna , Walas Stanisław , Soto Hernández Arlene, Mrowiec Halina
journal title:
Talanta
title of volume:
Selected Papers presented at the 17th ICFIA, Krakow, Poland (2011)
Na publikacji autorka Telk Anna podpisana jako Tobiasz Anna.
language:
English
journal language:
English
abstract in English:
The
paper
presents
application
of
multiwall
carbon
nanotubes
(MWCNTs)
modified
with
5-
dodecylsalicylaldoxime
to
copper(II)
flow-injection
on-line
preconcentration
and
flame
atomic
absorption
spectrometric
(FAAS)
determination.
Two
new
sorbents
were
obtained
by
impregnation
of
MWCNTs
with
Cu(II)-LIX
622
®
complex,
however
in
the
first
case
modification
was
preceded
by
carbon
wall
activation
via
oxidization
(Cu-LIX-CNT-A
sorbent),
and
in
the
second
one
no
surface
activation
was
performed
(Cu-LIX-CNT
sorbent).
It
was
found
that
effective
leaching
of
initially
introduced
copper
and
Cu(II)
retained
in
preconcentration
process
could
be
realized
with
the
use
7%
and
5%
(v/v)
nitric
acid,
for
particular
sorbents.
Testing
the
influence
of
loading
solution
pH
and
rate
of
loading
on
sorption
it
was
found
out
that
optimal
range
of
loading
solution
pH
was
about
4.5–6.3
for
activated
and
6.15–6.25
for
non-activated
CNT.
Investigation
of
sorption
kinetics
showed
that
the
process
can
be
described
by
pseudo-second
order
reaction
model.
Sorption
equilibrium
conditions
(90%
sorption)
for
LIX-CNT-A
and
LIX-CNT
were
obtained
after
8–15
min,
respectively
and
maximum
sorption
capacity
for
the
new
sor-
bents
amounted
to
18.1
mg
g
−
1
and
31.6
mg
g
−
1
,
respectively.
For
the
examined
sorbents
enrichment
factors
increased
with
extension
of
loading
time
up
to
180
s:
linearly
for
activated
and
non-linearly
for
non-activated
MWCNTs.
Influence
of
potential
interferents
such
as
Cd(II),
Zn(II),
Fe(III),
Mg(II)
and
Ca(II)
ions
on
copper(II)
sorption
on
the
new
CNT
materials
was
examined
individually
and
with
the
use
of
2
5–2
factorial
design.
The
study
revealed
significant
interference
from
iron,
magnesium
and
calcium
ions
at
relatively
high
concentrations.
Applicability
of
the
proposed
sorbents
was
tested
for
Cu(II)
determination
in
various
kinds
of
water
samples
and
the
results
were
compared
with
those
obtained
with
the
use
of
ICP
MS
as
a
reference
technique.
Copper(II)
determination
in
two
certified
reference
materials:
waste
water
(EU-H-3)
and
ground
(ES-H-2)
water
was
performed
in
order
to
assess
trueness
of
the
evaluated
preconcentration
procedures.
Satisfactory
values
of
relative
errors
were
obtained
for
both
procedures.