In this study, the adsorption behavior of Ni(II) in
an aqueous solution systemusing natural adsorbent
Peganum harmala
-L was measured via batch mode. The prepared sorbent
was characterized by scanning electron microscope,
Fourier transform infrared spectroscopy, N
2 adsorption–
desorption and pH
zpc. Adsorption experiments were carried
out by varying several conditions such as contact time, metal
ion concentration and pH to assess kinetic and equilibrium
parameters. The equilibrium data were analyzed based on the
Langmuir, Freundlich, Temkin and Dubinin–Radushkevich
isotherms. Kinetic data were analyzed using the pseudo-firstorder,
pseudo-second-order and intra-particular diffusion
models. Experimental data showed that at contact time
60 min, metal ion concentration 50 mg/L and pH 6, a maximumamount
ofNi(II) ions can be removed. The experimental
datawere best described by the Langmuir isothermmodel as is
evident from the high
R2 value of 0.988. The adsorption
capacity (
qm) obtained was 68.02 mg/g at an initial pH of 6
and a temperature of 25 °C. Kinetic studies of the adsorption
showed that equilibriumwas reachedwithin 60 min of contact
and the adsorption process followed the pseudo-first-order
model. The obtained results show that
P. harmala-L can be
used as an effective and a natural low-cost adsorbent for the
removal of Ni(II) from aqueous solutions.
