Utilization of Punica granatum carpellary membrane for removal of arsenic trivalent ions from aqueous medium

The present study focuses on adsorption of arsenic trivalent ions from water on pristine Punica granatum carpellary membrane (PPC) under different conditions including initial arsenic ions concentration in water, dose of PPC, pH, and time of contact. Scanning electron microscope, atomic emission spectroscopy, Brunauer-Emmett-Teller and energy-dispersive X-ray (EDX) techniques were used for confirmation of adsorption process. EDX spectrum of PPC did not exhibit any arsenic peak. However, additional arsenic peak was visible in EDX of PPC after adsorption which confirmed the adsorption of arsenic on adsorbent. Batch adsorption studies were performed to analyze the adsorption of arsenic trivalent ions on the adsorbent surface in various conditions. Optimum removal of arsenic was achieved at 60 mg/L of arsenite solution on 0.06 g/L of adsorbent dose at pH 5.0 for 120 min of contact time. Maximum adsorption (Langmuir) capacity was found to be 83.33 mg/g on the surface of PPC with 0.998 R-2 value. Pseudo-second-order kinetic model was found to be the best fitted model with 0.998 R-2 value. Pseudo-second-order calculated adsorption capacity at equilibrium (48.70 mg/g) was closed to experimental value (52.63 mg/g) also confirmed the best fitted model.