Microbial Fuel Cells (MFCs) remediation activity of marine sediments sampled at a dismissed industrial site: What opportunities?

Microbial Fuel Cells (MFCs) remedial technology was used for the degradation of Polycyclic Aromatic Hydrocarbons (PAHs) in marine sediments taken in front of the brownfleld steelwork facility of Bagnoli, Gulf of Pozzuoli, South Western Italy. PAHs levels were quite high and up to 30 mu g/g for fluoranthene and 0.21 mu g/g d.w. L of sediments for acenaphthene. Heavy PAHs prevailed vs light PAHs in the sediment samples before, during and after the treatment by MFCs. Different degradation rates were measured according to the complexity of each PAH, as expected. Among all PAHs, naphthalene showed after four weeks the highest degradation rate (86%), while just the 10% of Indenol[1,2,3-c,d]pyrene was degraded. MFCs achieved their highest performance in terms of Power Density (PD) after two weeks, with values ranging between 20.4 mW/m(2) and 3.17 mW/m(2) of anodic surface. CD values were normalized to the anodic surface as well, falling within a maximum of 204.8 mA/m(2) and a minimum of 9.5 mA/m(2). Even though the dynamics of PAHs degradation in MFCs and the influence of other pollutants (like metals) on MFCs performance as well as the potential mobilization of pollutants in consequence of microbial activity have to be ascertained, our preliminary results prove the high potentialities of MFCs for in-situ marine sediments remediation. (C) 2019 Elsevier Ltd. All rights reserved