In the present investigation, chemically modified JF
was evaluated as a novel bioadsorbent with enhanced adsorption capacity for the removal of an azo dye.
The study of influence of pH revealed that the adsorbent exhibited better adsorption
performance under acidic conditions
and achieved a maximum adsorption at a pH of ∼3.
The adsorbent dose inversely affected the adsorption capacity of modified JF, whereas the
adsorption capacity increased with increasing initial dye concentration.
The negative ΔG° values and negative ΔH° value,
as obtained from the thermodynamic study, established
the spontaneous and exothermic nature of CR adsorption.
The adsorption equilibrium data were fitted very well by the
Langmuir isotherm model, with R2 > 0.99.
The adsorption of the dye onto modified JF reached equilibrium in a short contact time, resulting in fast and efficient dye removal,
which would be beneficial
for practical purposes.
The rate of the adsorption process was found to conform reasonably well with the pseudosecond-order kinetic model.
The low value determined for the Arrhenius activation energy (9.31 kJ mol−1) suggests that CR adsorption on treated
JF is a physisorption process.
In addition,
the effective desorption of CR from the spent adsorbent with
0.1 M NaOH solution implies the involvement of an ionexchange
mechanism during adsorption.
Thus, the present investigation has provided a new efficient, stable, low-cost,economical, and environmentally safe adsorbent
with potential
for practical application in the treatment of dye-contaminated
wastewater.