Highway Runoff In Situ Treatment: Copper and Zinc Removal through MOGFC

Abstract

The primary objective of this study is to develop and evaluate multifunctional open-graded friction course (MOGFC) for use as an in situ treatment technique to remove Cu and Zn from highway runoff. First, the conventional porous pavement, open-graded friction course (OGFC), was prepared with varying air voids. Five different types of adsorbents were selected based on cost, applicability, and availability. Second, MOGFC was prepared by adding different adsorbents into the void of OGFC. A series of laboratory tests were conducted to evaluate the adsorption capacity of the adsorbents and metal removal efficiency of MOGFC. The tests included air void content, permeability, moisture susceptibility of OGFC and MOGFC, batch adsorption study of adsorbents, and metal removal by MOGFC. Results showed that three adsorbents have moderate to high adsorption capacity for copper (Cu) and zinc (Zn) removal from its aqueous solution. With these adsorbents, MOGFC could also considerably reduce metal concentration from the synthesized highway runoff. MOGFC mixtures used in this study were also highly resistant to moisture-induced damage. The results indicated that proposed in situ technique has a potential for field application as a result of its environmental and economic benefits.