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Kayıt Tarihi: 2021-13-Ocak
Aktif Durum: Pasif Gönderilenler: 30
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Gönderen: 2021-14-Ocak Saat 04:05 | Kayıtlı IP
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Enhancement of the adsorption of hexacyanoferrate (III)
ion on granular activated carbon by the addition of
cations: A promissory application to mining wastewater
treatment
The influence of the addition of cations on the
adsorption of [Fe(CN)6]3− on granular activated carbon
(GAC)carbon.com/">granular carbon was evaluated. The
tests were performed at three pH values (3, 8.2, and 13)
to determine the repulsion or electrostatic affinity
between the adsorbent and adsorbate. Afterward, the
cations (K+, Ca2+, and Al3+) at three pollutant-cation
molar ratios (1:1, 1:10, and 1:50) were added to the
system, and the influence of those was identified by the
changes in the adsorption efficiency. The results show
that the higher removal (%) was obtained at pH 13 without
neither the presence of iron precipitates nor the
liberation of HCN. The adsorption of [Fe(CN)6]3- was
enhanced by the addition of K+ at 1:10 and 1:50 mol ratio
since higher removals were achieved (75.27 % and 76.81 %
respectively) than those obtained in the absence of
cations (64.18 %) or in the presence of Ca2+ (67.58 %)
and Al3+ (65.13 %) at a 1:10 mol ratio. The behavior in
adsorption in the presence of cations shows that the ion-
pair adsorption mechanism can describe the physical
phenomenon, showing an increase in the fraction removed
and the rate of adsorption with increasing cation charge.
The adsorption kinetics using K+ with a 1:10 pollutant-
cation molar ratio was fitted to the Lagergren pseudo-
first-order model. The GAC adsorption capacity describes
the pollutant adsorption rate with the predominance of
physical interactions.
coal carbon
manufacturer The experimental data were fitted by
the Langmuir and Freundlich isotherms, indicating a
monolayer adsorption phenomenon consistent with the
previously proposed ion-pair adsorption mechanism.
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