Removal of Cd(II) ions from aqueous solutions by nanodiopside as a novel and green adsorbent: Optimisation by response surface methodology
Shima Ghanavati Nasab, Abbas Teimouri, Mansoureh Hemmasi, Zahra Jafari Harandi, Mehdi Javaheran Yazd
Abstract
In this research, adsorption removal of cadmium ions from aqueous solutions by nanodiopside as a novel, green, and efficient adsorbent was studied. The prepared nanodiopside was characterised by FESEM, FTIR, XRD, EDX, TEM and BET analyses. All of the analyses indicated that the nanodiopside was synthesised correctly. The effect of several parameters on the removal percentage of the copper was investigated by central composite design and the optimal condition of parameters for maximum Cd2+ adsorption process was as follows: pH = 5.60, adsorbent dosage: 0.13 mg, Cd2+ concentration: 23.16 mg L−1, contact time: 43.83 min, and temperature: 34.75 ◦C, respectively. The kinetic and equilibrium data were explained by Pseudo-second-order (R2: 0.999) and Freundlich models (qmax: 124.92 mg g−1 and R2: 0.998), respectively. The results of the reusability of nanodiopside after six sorption desorption cycles provide a promising potential for future industrial activities.