Chemophysical Evaluation of Green Sorption Media for Copper Removal in Stormwater Runoff for Improving Ecosystem and Human Health

Abstract

Green sorption media, which includes the utilization of renewable and recycled materials, can be used as a means for nutrient and copper removal in various low-impact development facilities. In this study, a green sorption media mixture consisting of recycled tire chip, expanded clay, and coconut coir was physiochemically evaluated for copper removal potential in stormwater runoff to deepen the understanding of its application potential. Isotherm, reaction kinetics, and life expectancy tests were conducted using both the media mixture and the individual components of the green sorption media. In addition, the media mixture was analyzed to determine its life expectancy. Isotherm test results revealed that the media mixture follows the Freundlich model and that the coconut coir had the highest affinity for copper. Distinct dynamic adsorption models were explored to determine the most suitable model for implementation based on a column test data set. Five dynamic adsorption models, including the Thomas, Clark, Bohart-Adams, Wolborska, and modified dose-response models, were investigated and the media mixture data collected in the column test were fitted into these five models, leading to the selection of the best model with the highest correlation. The modified dose-response model outperformed others in terms of the overall media mixture and the coconut coir. Life expectancy estimation showed that the media mixture has a life span of 2.13 years with the chosen influent conditions and can be applicable for improving the performance of water quality management in stormwater detention and retention ponds, bioswale, and other stormwater best management practices.