Self-assembled organobentonite employed to remove Reactive Blue 13 exhibited
93% dye removal in one step process according to Langmuir adsorption isotherm
model (Yao et al. 2012). In another study, surfactant-modified bentonite was also
evaluated for the removal of 6, which was reasonably explained by Langmuir
adsorption isotherm and pseudo-second-order models with spontaneous and endothermic properties (Akl et al. 2013). Modified clay, phenol, and catechol were
removed from water by Na-montmorillonites in the batch adsorption process. Langmuir adsorption isotherm best explained the adsorption process. Pseudo-secondorder kinetics, spontaneous, and exothermic nature was observed (Jourvand et al.
2015; Liu et al. 2014b).
Bis-imidazolium cations were used to modify bentonite to adsorb telon-orange,
telon-red, and telon-blue dyes, which were explained better by Langmuir adsorption
isotherm model with pseudo-second-order kinetics (Makhoukhi et al. 2015).
Organobentonite was studied for the adsorptive removal of Acid Green 25 at three
different temperatures (30, 40, and 50
C). Result correlated to the Langmuir
adsorption isotherm model with q max 3.7 mmol g
À1 , and kinetics reported was
pseudo-second-order kinetics (Koswojo et al. 2010). Organobentonite prepared
from microwave radiation from a natural source, rarasaponin, was investigated for
the removal of 1 and 2. The adsorption data was best suited to Langmuir adsorption
isotherm model and provided satisfactory results for the usage of that adsorbent to
remove 1 and 2 (Kurniawan et al. 2012).
7 was removed by manganese oxide-coated sepiolite as an adsorbent with q max
value of 319 mg g
À1 described by Langmuir adsorption isotherm. Moreover,
adsorbent showed pseudo-second-order kinetics (Eren et al. 2010). Surface modifications of bentonite carried out using benzyltrimethylammonium chloride,
hexadecyltrimethylammonium bromide, and tris(hydroxymethyl)aminomethane
surfactants showed enhanced adsorption against 6. The results were explained by
Langmuir adsorption isotherm model and pseudo-second-order kinetics with spontaneous and endothermic nature (Fosso-Kankeu et al. 2016). Organobentonite successfully removed Acid Red 1 and 9 from aqueous solutions. The batch adsorption
experiments provided the q max values as 157.4 and 173.5 mg g
À1 for Acid Red 1 and
9 at pH 9. Results correlated with Langmuir adsorption isotherm model and pseudosecond-order kinetics (Huang et al. 2017).
In a similar study, organic modifications of hydroxyapatite with
ethylhexadecyldimethyl ammonium bromide were carried out to remove 2. The
results complied with Langmuir adsorption isotherm model showing q max value of
188.0 mg g
À1 and kinetics studied revealed pseudo-second-order kinetics (El-Zahhar
and Awwad 2016). In another study, poly(epicholorohydrin dimethylamine)modified bentonite was used for removal of direct fast scarlet, eosin Y, and reactive
violet K-3R dyes with q max values of 148, 106, and 88 mg g
À1
, respectively,
following Langmuir adsorption isotherm model and pseudo-second-order kinetics
(Kang et al. 2009). Montmorillonite-iron oxide was applied to remove 1 from
aqueous solution. Results correlated with Langmuir adsorption isotherm model
showing q max value of 71.12 mg g
À1 , and pseudo-second-order kinetics was
observed (Cottet et al. 2014).
614
R. S. Ashraf et al.
93% dye removal in one step process according to Langmuir adsorption isotherm
model (Yao et al. 2012). In another study, surfactant-modified bentonite was also
evaluated for the removal of 6, which was reasonably explained by Langmuir
adsorption isotherm and pseudo-second-order models with spontaneous and endothermic properties (Akl et al. 2013). Modified clay, phenol, and catechol were
removed from water by Na-montmorillonites in the batch adsorption process. Langmuir adsorption isotherm best explained the adsorption process. Pseudo-secondorder kinetics, spontaneous, and exothermic nature was observed (Jourvand et al.
2015; Liu et al. 2014b).
Bis-imidazolium cations were used to modify bentonite to adsorb telon-orange,
telon-red, and telon-blue dyes, which were explained better by Langmuir adsorption
isotherm model with pseudo-second-order kinetics (Makhoukhi et al. 2015).
Organobentonite was studied for the adsorptive removal of Acid Green 25 at three
different temperatures (30, 40, and 50
C). Result correlated to the Langmuir
adsorption isotherm model with q max 3.7 mmol g
À1 , and kinetics reported was
pseudo-second-order kinetics (Koswojo et al. 2010). Organobentonite prepared
from microwave radiation from a natural source, rarasaponin, was investigated for
the removal of 1 and 2. The adsorption data was best suited to Langmuir adsorption
isotherm model and provided satisfactory results for the usage of that adsorbent to
remove 1 and 2 (Kurniawan et al. 2012).
7 was removed by manganese oxide-coated sepiolite as an adsorbent with q max
value of 319 mg g
À1 described by Langmuir adsorption isotherm. Moreover,
adsorbent showed pseudo-second-order kinetics (Eren et al. 2010). Surface modifications of bentonite carried out using benzyltrimethylammonium chloride,
hexadecyltrimethylammonium bromide, and tris(hydroxymethyl)aminomethane
surfactants showed enhanced adsorption against 6. The results were explained by
Langmuir adsorption isotherm model and pseudo-second-order kinetics with spontaneous and endothermic nature (Fosso-Kankeu et al. 2016). Organobentonite successfully removed Acid Red 1 and 9 from aqueous solutions. The batch adsorption
experiments provided the q max values as 157.4 and 173.5 mg g
À1 for Acid Red 1 and
9 at pH 9. Results correlated with Langmuir adsorption isotherm model and pseudosecond-order kinetics (Huang et al. 2017).
In a similar study, organic modifications of hydroxyapatite with
ethylhexadecyldimethyl ammonium bromide were carried out to remove 2. The
results complied with Langmuir adsorption isotherm model showing q max value of
188.0 mg g
À1 and kinetics studied revealed pseudo-second-order kinetics (El-Zahhar
and Awwad 2016). In another study, poly(epicholorohydrin dimethylamine)modified bentonite was used for removal of direct fast scarlet, eosin Y, and reactive
violet K-3R dyes with q max values of 148, 106, and 88 mg g
À1
, respectively,
following Langmuir adsorption isotherm model and pseudo-second-order kinetics
(Kang et al. 2009). Montmorillonite-iron oxide was applied to remove 1 from
aqueous solution. Results correlated with Langmuir adsorption isotherm model
showing q max value of 71.12 mg g
À1 , and pseudo-second-order kinetics was
observed (Cottet et al. 2014).
614
R. S. Ashraf et al.