A chemical remediation technique for a nearly-total removal of arsenic and mercury from contaminated marine sediments

• DOI: 10.1016/j.heliyon.2023.e22633
• Publication Date: 2023-11-19T15:30:10Z
• Authors: Fabio D'Agostino; Antonio Bellante; Maria Bonsignore; Marianna Del Core; Laura Clarizia; Nadia Sabatino; Luigi Giaramita; Giorgio Tranchida; Salvatore Chiavarini; Mario Sprovieri
• Keywords: Mercury; Mercury contamination

After decades of industrial exploitation the coast and consequent contamination sites marine sediments, it became essential to recover ecosystem by remediation methods remove toxic contaminants. In this work, a method was developed clean sediments contaminated arsenic (As) mercury (Hg). The can be applied mobile platforms is based on an environmentally friendly approach designed minimise further contamination. tested two artificially real samples collected from highly in southern Italy, Augusta Bay Bagnoli Gulf, characterised high Hg As concentrations, respectively. consists four steps: washing with sodium hydroxide (NaOH) metals associated humic acid; Fenton-reaction using α-CycloDextrin (aCD) stabilise Fe(II) at natural pH oxidise (III) (0 or I); complexation reaction aCD; sulfide (Na2S) as soluble Hg-polysulfides. Compared other experiences literature, technique provides best removal efficiency for (ranging between 26 -71 % 57–95 %, respectively). Considering residual concentrations threshold fixed European Regulation re-use, treated sediment used several civil contexts. presented operates line principles circular economy preserve resources, prevent secondary pollution, promote effective re-use environmental matrices (soils, aqueous solutions), thus minimising landfill waste.