Abstract

The chemically treated agro-waste as adsorbent for the purification of wastewater contaminated with heavy metals.
Pumpkin husk as an excellent adsorbent for removal of Cu(II) and Ni(II) ions. It depended on the controlling
parameters such as pH, contact time, initial metal ion concentration, adsorbent dosage, and temperature. pH 5
was found to be suitable for Cu(II) and Ni(II) ions. Equilibrium, thermodynamic, and kinetic data were well
fitted (R2=0.997). Thermodynamic parameters such as ΔG°, ΔH°, and ΔS° have also been evaluated, and it has
been found that the adsorption process was spontaneous, endothermic, and randomness in nature. The Langmuir
adsorption isotherm data fitted well. The kinetic experimental data correlated well with the second order kinetic
model. The results concluded that the treated pumpkin husk (TPH) was an eco-friendly, economically cheap and
effective adsorbent in the removal of Cu(II) and Ni(II) ions from aqueous solution.