In the present study peach seed
powder (PSP) was used as an adsorbent to remove Acid Blue 25 (AB25) a common
basic dye, from aqueous solution. The adsorption experiments were carried out
in a batch system and the effects of initial concentration, interaction time
and temperature were investigated. The Langmuir, Freundlich and Temkin
adsorption isotherms were used to model the equilibrium data. The kinetic
parameters were determined by the pseudo first order (PFO), pseudo second order
(PSO) and intra-particle diffusion (IPD) models. According to the results, the
Freundlich isotherm model is a more convenient option compared with the
Langmuir and Temkin models. The Freundlich model coefficients increased as the
temperature increased, which shows that the adsorption process becomes more
favorable with higher temperature. The experimental and calculated qe values close to one
another indicated that this process fits the PSO kinetic model with higher R2
values than the other two models. Kinetic constants become closer to both the
temperatures and initial concentrations and qe
values increases with the increasing concentration of AB25. The initial dye
concentration increased from 25 to 150 mg L-1, while the dye
adsorption capacity onto PSP increased from 4.80 to 39.01 mg g-1,
from 5.57 to 44.27 mg g-1 and from 6.80 to 49.22 mg g-1
for 298, 308 and 323 K, respectively. The monolayer adsorption capacity (qm) of PSP was determined to
be 56.18, 64.94, 95.24 mg g-1 for 298, 308 and 323 K, respectively.
Thermodynamic parameters for free energy (ΔG),
enthalpy (ΔH) and entropy (ΔS) of the separation process were
determined as -1737,1 J mol-1, 14.776 kJ mol-1 and 55,413
J mol-1, respectively. The negative values of ΔGo showed that this separation process was endothermic and natural. The
results of the present study demonstrated that PSP can be used as an
alternative material in dye removal.
Peach seed powder dye adsorption isotherm models kinetic constants acid blue 25 thermodynamic parameters
Primary Language | English |
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Subjects | Environmental Engineering |
Journal Section | Research Articles |
Authors | |
Publication Date | December 31, 2019 |
Submission Date | November 24, 2019 |
Acceptance Date | December 13, 2019 |
Published in Issue | Year 2019 |