(Elsevier, 2020) López Rodríguez, José Javier; Echeverría Morrás, Jesús; San Martín González, Iban; Delgado Zabala, Oihane; Ingeniería; Ingeniaritza; Institute of Smart Cities - ISC; Institute for Advanced Materials and Mathematics - INAMAT2; Universidad Pública de Navarra/Nafarroako Unibertsitate Publikoa
The increase in urban runoff brought about by a rise in impermeable surfaces has triggered the alteration and pollution of many aquatic systems. The overall goal of this research was to design a ‘Sustainable Urban Drainage System’ (SUDS) for the retention of heavy metals from a car park consisting of mixing autochthonous soil (70%) with
sand (30%) to improve the hydrological conductivity and adsorption capacity. To quantify the retention of metals
we characterize the adsorption kinetics and isotherms of the soil mixture and perform dynamic experiments. The
proposed methodology allowed us to work out the amount of heavy metal retention by the adsorbent and the
retention mechanisms. The retention capacity of the adsorbent mixture was as follows: Cr3+ ≈ Cu2+ ≫ Zn2+ N
Ni2+ N Cd2+. Chromium and copper ions were mainly retained by precipitation, whereas zinc, nickel and cadmium were retained by ionic exchange with calcium ions that saturate the soil colloids. The soil mixture buffered
pH was found to change when fed with an acid solution of metallic ions.
