Hexagonal Boron Nitride (h-BN) in Solutes Separation
179
absorbent performance for oils compared to other commercial bulk BN and activated
carbon, which exhibits that the nanosheet structure influences the absorption capability and increases it. Due to the synergy of swelling and porosity features, the porous
BNNSs showed a higher adsorption capacity compared with non-porous BNNSs.
The porous BNNSs exhibited excellent adsorption of varied types of solvents, oils,
and dyes, with mass uptakes values ranging from 2000 to 3300 wt%, which can be
promising in the treatment of contaminated water. Furthermore, the saturated BNNSs
can be reused several cycles for environmental restoration via regeneration. Considering the intense resistance of the BNNSs, the adsorbed materials can be simply
eliminated from the collected BNNSs by heating in the furnace and directly burning
in air. The BN adsorbents are very sturdy and can be reused many times without
loss of activity. The simple recycling of BNNSs suggests the eminent potential it in
wastewater treatment applications.
Li et al. [79] synthesized microporous and mesoporous BN materials through
a simple two-step method, which exhibited ultrahigh specific surface area
(1687 m
2 .g
−1 ) and a large pore volume (0.99 cm
3 .g
−1 ). The morphology and structural properties of the BN samples were checked applying XRD, SEM, FTIR, and
SEM. They studied porous BN performance in water treatment by introducing 100 mg
porous BN material into 250 ml of model dye solution with the initial concentration
of 40 mg.l
−1 . Results revealed that ~88 wt% of model dye is prominently eliminated
from the solution after 5 min, and ~99 wt% of model dye is adsorbed after 2 h at room
temperature. The obtained data were also fitted to the Langmuir isotherms, which has
been extensively applied to characterize the adsorption of pollutants from solutions.
The correlation coefficient and the maximum adsorption capacity of porous BN for
model dye were calculated to be 0.991 and 298.3 mg.g
−1 , respectively.
Moreover, the porous BN was used to remove copper ions from solutions. They
investigated the adsorption capacity of copper ions by mixing 250-ml solution with
copper ion concentration of 1.86 mg.g
−1 and 1 g porous BN, which results indicated 373 mg.g
−1 maximum removing capacity of copper ions. The BN exhibited
outstanding potential for adsorption of model dye and copper ions, attributing to
pore volume, superior surface area, and structural defects of porous BN. Additionally, regeneration of collected porous BN was easily performed after the treatment
process by calcining at 350 °C for 2 h in air.
In the other work, an activated oxygen-rich porous BNNSs (OBNNSs) was synthesized by Li et al. [80] for improving the adsorption performance of BNNSs in water
purification. They tested the morphology and structural properties of the samples
using XRD, SEM, and TEM. In order to compare, the adsorption performances of
commercial granular activated carbon (GAC) as well as bulk BN were also measured.
In order to reach the contaminated water solution, each of Pb(NO 3 ) 2 , HgCl 2 , CrCl 3 ,
and CuCl 2 was dissolved in water and then diluted to obtain the needed concentration.
They performed adsorption kinetic tests to approximate the metallic ions adsorption
rates in the OBNNSs, GAC, and bulk BN. As depicted in Fig. 13, the elimination of
Pb(II) by the OBNNSs enhanced quickly by rising contact time.
GAC and bulk BN showed very low adsorption efficiency in contrast to the
OBNNSs during the same time. Furthermore, the adsorption performance of various
179
absorbent performance for oils compared to other commercial bulk BN and activated
carbon, which exhibits that the nanosheet structure influences the absorption capability and increases it. Due to the synergy of swelling and porosity features, the porous
BNNSs showed a higher adsorption capacity compared with non-porous BNNSs.
The porous BNNSs exhibited excellent adsorption of varied types of solvents, oils,
and dyes, with mass uptakes values ranging from 2000 to 3300 wt%, which can be
promising in the treatment of contaminated water. Furthermore, the saturated BNNSs
can be reused several cycles for environmental restoration via regeneration. Considering the intense resistance of the BNNSs, the adsorbed materials can be simply
eliminated from the collected BNNSs by heating in the furnace and directly burning
in air. The BN adsorbents are very sturdy and can be reused many times without
loss of activity. The simple recycling of BNNSs suggests the eminent potential it in
wastewater treatment applications.
Li et al. [79] synthesized microporous and mesoporous BN materials through
a simple two-step method, which exhibited ultrahigh specific surface area
(1687 m
2 .g
−1 ) and a large pore volume (0.99 cm
3 .g
−1 ). The morphology and structural properties of the BN samples were checked applying XRD, SEM, FTIR, and
SEM. They studied porous BN performance in water treatment by introducing 100 mg
porous BN material into 250 ml of model dye solution with the initial concentration
of 40 mg.l
−1 . Results revealed that ~88 wt% of model dye is prominently eliminated
from the solution after 5 min, and ~99 wt% of model dye is adsorbed after 2 h at room
temperature. The obtained data were also fitted to the Langmuir isotherms, which has
been extensively applied to characterize the adsorption of pollutants from solutions.
The correlation coefficient and the maximum adsorption capacity of porous BN for
model dye were calculated to be 0.991 and 298.3 mg.g
−1 , respectively.
Moreover, the porous BN was used to remove copper ions from solutions. They
investigated the adsorption capacity of copper ions by mixing 250-ml solution with
copper ion concentration of 1.86 mg.g
−1 and 1 g porous BN, which results indicated 373 mg.g
−1 maximum removing capacity of copper ions. The BN exhibited
outstanding potential for adsorption of model dye and copper ions, attributing to
pore volume, superior surface area, and structural defects of porous BN. Additionally, regeneration of collected porous BN was easily performed after the treatment
process by calcining at 350 °C for 2 h in air.
In the other work, an activated oxygen-rich porous BNNSs (OBNNSs) was synthesized by Li et al. [80] for improving the adsorption performance of BNNSs in water
purification. They tested the morphology and structural properties of the samples
using XRD, SEM, and TEM. In order to compare, the adsorption performances of
commercial granular activated carbon (GAC) as well as bulk BN were also measured.
In order to reach the contaminated water solution, each of Pb(NO 3 ) 2 , HgCl 2 , CrCl 3 ,
and CuCl 2 was dissolved in water and then diluted to obtain the needed concentration.
They performed adsorption kinetic tests to approximate the metallic ions adsorption
rates in the OBNNSs, GAC, and bulk BN. As depicted in Fig. 13, the elimination of
Pb(II) by the OBNNSs enhanced quickly by rising contact time.
GAC and bulk BN showed very low adsorption efficiency in contrast to the
OBNNSs during the same time. Furthermore, the adsorption performance of various