Modification of sand with iron and copper derived from electroplating wastewater for efficient adsorption of phosphorus from aqueous solutions: A combinatorial approach for an effective waste minimization

The focus of the this work is to develop mesoporous silica and amine modified sand loaded with iron (Fe) and copper (Cu) species from electroplating wastewater for a further removal of phosphorus (P) from wastewater. First, it is shown that Fe or Cu supported sand adsorbent can effectively remove phosphorus (P) from aqueous solutions. The influence of pH, initial ion concentration (C-0), contact time (t) on the adsorption of P by both sand adsorbents was studied. The maximum adsorption efficiency at room temperature reached 98% for the Fe-supported adsorbent under conditions of pH = 4, C-0 = 25 mg/L, t = 180min and 96.3% for the Cu-supported sand under conditions of pH = 2, C-0 = 5 mg/L, t = 120min respectively. The kinetics of P adsorption by the Fe or Cu supported sands followed the pseudo second order kinetic model, while the adsorption isotherms fitted the Langmuir model. Based on the above results, an iron and copper co-supported sand adsorbent was prepared successfully by encapsulating Fe and Cu from a copper electroplating wastewater. In the meantime, Cu in the electroplating wastewater was reduced from 222 to 0.12 mg/L. This wastewater derived sand-based adsorbent had the same efficiency as the Fe-supported sand adsorbent. It was used to remove P from aqueous solution until the residual P in solution met China National Standard of WastewaterEmission. By this way, a dual approach to synergistically purify both anions and cations polluted wastewaters is developed. (C) 2018 Elsevier Ltd. All rights reserved.