319
hydroxide and boron. It was found that the adsorption mechanism was occurred
according to both Langmuir and Freundlich isotherm models (Prodromou 2004a, b).
Mg-Al(NO 3 ) layered double hydroxide was used to investigate the boron removal
from wastewater. The maximum adsorption occurred at alkaline pH level (9.0–9.2).
A combination of electrostatic attractions and ion-exchange processes was the
major forces for the adsorption of boron (Kentjono et al. 2010).
Mg-Al(NO 3 ) and Mg-Al(Cl) layered double hydroxides were synthesized by
Kameda et al. (2015) for the removal of boron. Ion-exchange mechanism was the
driving force for boron adsorption, which occurred between NO 3
−
or Cl
−
ions and
B(OH) 4
−
ions. Langmuir isotherm model was best fitted the experimental data, and
the maximum adsorption capacity was found at 3.6 and 3.8 mmol g
−1
for Mg-Al(NO 3 )
and Mg-Al(Cl), respectively (Kameda et al. 2015).
Zn 2 Al-Cl layered double hydroxide was synthesized by Koilraj and Srinivasan
(2011). Maximum boron adsorption was achieved at 31 mg g
−1
after calcination of
layered double hydroxides. Boron adsorption occurred according to Langmuir isotherm model, and boron removal was constant between pH 3 and 7 (Koilraj and
Srinivasan 2011).
Mg-Al layered double hydroxide was calcined at 450 °C and used for boron
removal. Initial boron concentration was 5 mg L
−1
, which is the boron content in
seawater. Adsorption capacity of layered double hydroxides was found as 33 mg g
−1
(Liu et al. 2014).
Qiu et al. (2014) synthesized hydrotalcite intercalated with d-gluconate for boron
adsorption. Adsorption capacity of layered double hydroxides was found as
1.27 mmol g
−1
according to Langmuir isotherm model (Qiu et al. 2014).
12.6 Conclusion
Boron is an essential element for plants, animals, and humans. However, there is a
narrow gap between boron deficiency and toxicity. Therefore, boron removal from
water is an important issue. There are numerous materials that can be used for boron
removal. Natural materials, such as clay minerals, can be used for boron removal.
However, most of them should be modified with a modification agent or synthesized
its homoionic form to change the surface charge of the clay. On the other hand, lowcost industrial wastes also can be used at high boron concentrations with a high
adsorption capacity. Complexation reactions are the major mechanism for boron
adsorption. Layered double hydroxides (LDH) are another type of adsorbents that
can be used for boron removal. However, they have low adsorption capacities and
can be used for low boron concentrations. LDH synthesis is a new research area and
can be improved in the future studies.
12 Application of Adsorption Methods for Boron Uptake
hydroxide and boron. It was found that the adsorption mechanism was occurred
according to both Langmuir and Freundlich isotherm models (Prodromou 2004a, b).
Mg-Al(NO 3 ) layered double hydroxide was used to investigate the boron removal
from wastewater. The maximum adsorption occurred at alkaline pH level (9.0–9.2).
A combination of electrostatic attractions and ion-exchange processes was the
major forces for the adsorption of boron (Kentjono et al. 2010).
Mg-Al(NO 3 ) and Mg-Al(Cl) layered double hydroxides were synthesized by
Kameda et al. (2015) for the removal of boron. Ion-exchange mechanism was the
driving force for boron adsorption, which occurred between NO 3
−
or Cl
−
ions and
B(OH) 4
−
ions. Langmuir isotherm model was best fitted the experimental data, and
the maximum adsorption capacity was found at 3.6 and 3.8 mmol g
−1
for Mg-Al(NO 3 )
and Mg-Al(Cl), respectively (Kameda et al. 2015).
Zn 2 Al-Cl layered double hydroxide was synthesized by Koilraj and Srinivasan
(2011). Maximum boron adsorption was achieved at 31 mg g
−1
after calcination of
layered double hydroxides. Boron adsorption occurred according to Langmuir isotherm model, and boron removal was constant between pH 3 and 7 (Koilraj and
Srinivasan 2011).
Mg-Al layered double hydroxide was calcined at 450 °C and used for boron
removal. Initial boron concentration was 5 mg L
−1
, which is the boron content in
seawater. Adsorption capacity of layered double hydroxides was found as 33 mg g
−1
(Liu et al. 2014).
Qiu et al. (2014) synthesized hydrotalcite intercalated with d-gluconate for boron
adsorption. Adsorption capacity of layered double hydroxides was found as
1.27 mmol g
−1
according to Langmuir isotherm model (Qiu et al. 2014).
12.6 Conclusion
Boron is an essential element for plants, animals, and humans. However, there is a
narrow gap between boron deficiency and toxicity. Therefore, boron removal from
water is an important issue. There are numerous materials that can be used for boron
removal. Natural materials, such as clay minerals, can be used for boron removal.
However, most of them should be modified with a modification agent or synthesized
its homoionic form to change the surface charge of the clay. On the other hand, lowcost industrial wastes also can be used at high boron concentrations with a high
adsorption capacity. Complexation reactions are the major mechanism for boron
adsorption. Layered double hydroxides (LDH) are another type of adsorbents that
can be used for boron removal. However, they have low adsorption capacities and
can be used for low boron concentrations. LDH synthesis is a new research area and
can be improved in the future studies.
12 Application of Adsorption Methods for Boron Uptake