Vol.:(0123456789)
Research on Chemical Intermediates (2020) 46:2055–2068
https://doi.org/10.1007/s11164-019-04069-8
1 3
Application of magnetic graphene-based bucky gel
as an efcient green sorbent for determination of mercury
in fsh and water samples
Fateme Faryadras
1
· Seyedeh Mahboobeh Yousef
1
· Parastoo Jamshidi
1
·
Farzaneh Shemirani
1
Received: 6 August 2019 / Accepted: 30 December 2019 / Published online: 28 February 2020
© Springer Nature B.V. 2020
Abstract
In this article, a highly efficient method based on coupling magnetic solid-phase
extraction and dispersive microsolid-phase extraction was proposed to preconcen-
trate Hg
2+
. In this technique, extraction of Hg
2+
was carried out by magnetic gra-
phene-based bucky gel (MGBG). MGBG was prepared by dispersing magnetic gra-
phene (MG) in a [Hmim][BF
4
]. Utilization of [Hmim][BF
4
] led to better dispersion
of MG in aqueous solution and decreased the extraction time. In addition, MG was
separable by an external magnet so filtration steps were omitted. The sorbent was
characterized by X-ray diffraction, scanning electron microscopy, alternating gradi-
ent force magnetometer and Fourier transform infrared spectroscopy. The precon-
centration conditions were optimized as pH value of 1 ± 0.2, dithizone concentration
of 8 × 10
−6
mol L
−1
, [Hmim][BF
4
] volume of 50 μL, MG amount of 5 mg, n-hexane
volume of 200 μL and elution time of 5 min. The quantification of Hg
2+
was carried
out by UV–visible spectroscopy. Under the optimized conditions, limit of detection
(2.11 μg L
−1
), relative standard deviation (2.59%), preconcentration factor (150) and
linearity of dynamic range (7–100 μg L
−1
) were calculated which showed high reli-
ability of sorbent to preconcentrate Hg
2+
. The effect of interference ions was investi-
gated. The method was successfully applied to preconcentrate Hg
2+
in fish and water
samples. To better understand the adsorption of Hg
2+
onto MGBG, thermodynamic
of adsorption is reported.
Keywords Magnetic bucky gel · Mercury · Spectrophotometry · Ionic liquid · Fish
* Farzaneh Shemirani
Shemiran@khayam.ut.ac.ir; fshemirani@ut.ac.ir
1
School of Chemistry, College of Science, University of Tehran, P.O. Box 14155-6455 Tehran,
Iran