Study of physicochemical changes of polluted sediments from Reconquista river basin (Argentina) after remediation processes

MELISA OLIVELLI; M SIMPSON; PORZIONATO NATALIA; M A FERNANDEZ ; R M TORRES SÁNCHEZ; CURUTCHET GUSTAVO

International Journal of Environment and Health

Inderscience Publishers

Año: 2018

1743-4955

The physicochemical properties of sediments and their ability to retain pollutants are affected both by contamination and by remediation processes. The aim of this study is to determine structural and physicochemical changes in real sediment contaminated with metals, subjected to bioleaching processes in a previous study. The sediment contaminated with heavy metals and samples of the same sediment treated with different heap leaching tests were used. They were characterised by potentiometric titrations, electrophoretic mobility, organic matter (OM), nuclear magnetic resonance, volatile solids and sulfides. For contaminated and treated sediment samples, the results of organic matter, sulfides, volatile solids heated to 600 degrees, potentiometric titrations and surface charge depended on the bioleaching treatment performed previously. The contaminated sediment sample without any bioleaching treatment presented the greatest amount of OM and sulfides. Moreover, metal adsorption isotherms were derived. The contaminated sediment without bioleaching treatment was the one with the highest adsorption capacity. The pristine sample did not present a noticeable adsorption capacity. This study indicates the importance of the contribution of OM and sulfides to sediments and structural and physicochemical studies after remediation treatments.