Zinc chloride modification of sage leaves powder and its application as an adsorbent for KMnO4 removal from aqueous solutions

Abstract

Sage Leaves Powder was modified by 30% w/w of Zink Chloride (ZnCl _2 ) and used as a cheap adsorbent for potassium permanganate (KMnO _4 ) adsorption from aqueous media. The characterization of the synthesized adsorbent showed diversity in its functional groups at 1030, 1700, and 2930 cm ^−1 . The impact of experimental conditions on the adsorption was investigated. It was found that these experimental conditions except pH have positive effects on the efficiency of this adsorbent. The initial KMnO _4 concentration of 1500 mg l ^−1 , the temperature of 60 °C and the solution pH of 1.5 were found to be the ideal conditions in this adsorption. The equilibrium data were analyzed using three isotherm models. Langmuir model was found to be the best model applied in this work. The adsorption capacities were 714.29, 769.23, 833.33 and 909.09 (mg g ^−1 ) at 30, 40, 50 and 60 (°C), respectively. The parameters of the adsorption kinetics were evaluated by three kinetic models. The kinetic results confirm that the 2nd order described well the experimental data. Thermodynamic outcomes suggest that this adsorption is a spontaneous and endothermic process. The obtained results make from this adsorbent a good option for KMnO _4 removal from wastewater in terms of its low-cost and adsorption performance.

Keywords

• sage leaves
• adsorption
• KMnO4
• isotherms
• kinetics
• thermodynamics