Scheda di dettaglio – i prodotti della ricerca
| Dato | Valore |
|---|---|
| Title | Influence of nitrate and sulphate reduction in the biolectrochemically assisted dechlorination of cis-DCE |
| Abstract | This paper investigated the reductive dechlorination (RD) of cis-dichloroethylene (cis-DCE) (average influent 14.2 ± 0.7 ?M) by a bioelectrochemical system (BES), in the presence of real contaminated groundwater containing high levels of nitrate and sulfate. The BES enhanced both the RD and competing reactions, such as nitrate and sulfate reductions, which occurred with neither an external organic carbon source nor any inoculum other than the indigenous microbial consortia in the real groundwater. In preliminary batch tests, RD and full nitrate removal occurred after a short lag phase, whereas sulfate reduction occurred slowly and alongside the RD. Under continuous flow conditions (hydraulic retention time, HRT, 1.4 d), the competition of different electron acceptors was strongly affected by the cathodic potential in the range -550 to -750 mV vs. standard hydrogen electrode (SHE). Nitrate reduction was driven to completion at all tested cathodic potentials, whereas sulfate reduction and the RD rate increased as the cathodic potential became more negative. At -750 mV vs. SHE, strong methanogenesis was also observed and became the most important sink of electrons. The overall coulombic efficiency decreased while the potential became more negative. The RD contribution was always less than 1%. Hence, greater energy consumption was required to obtain higher RD rate and better conversion. Anodic oxidation was only observed at -750 mV vs. SHE where almost 39% of residual vinyl chloride (VC) was oxidized and the sulfate was formed back from sulfide (further contributing to electric waste). |
| Source | Chemosphere |
| Journal | Chemosphere |
| Editor | Elsevier, Oxford, Regno Unito |
| Year | 2015 |
| Type | Articolo in rivista |
| DOI | 10.1016/j.chemosphere.2014.12.023 |
| Authors | Agnese Lai, Roberta Verdini, Federico Aulenta, Mauro Majone |
| Text | 300479 2015 10.1016/j.chemosphere.2014.12.023 Influence of nitrate and sulphate reduction in the biolectrochemically assisted dechlorination of cis DCE Agnese Lai, Roberta Verdini, Federico Aulenta, Mauro Majone Sapienza Universita di Roma; National Research Council This paper investigated the reductive dechlorination RD of cis dichloroethylene cis DCE average influent 14.2 ± 0.7 M by a bioelectrochemical system BES , in the presence of real contaminated groundwater containing high levels of nitrate and sulfate. The BES enhanced both the RD and competing reactions, such as nitrate and sulfate reductions, which occurred with neither an external organic carbon source nor any inoculum other than the indigenous microbial consortia in the real groundwater. In preliminary batch tests, RD and full nitrate removal occurred after a short lag phase, whereas sulfate reduction occurred slowly and alongside the RD. Under continuous flow conditions hydraulic retention time, HRT, 1.4 d , the competition of different electron acceptors was strongly affected by the cathodic potential in the range 550 to 750 mV vs. standard hydrogen electrode SHE . Nitrate reduction was driven to completion at all tested cathodic potentials, whereas sulfate reduction and the RD rate increased as the cathodic potential became more negative. At 750 mV vs. SHE, strong methanogenesis was also observed and became the most important sink of electrons. The overall coulombic efficiency decreased while the potential became more negative. The RD contribution was always less than 1%. Hence, greater energy consumption was required to obtain higher RD rate and better conversion. Anodic oxidation was only observed at 750 mV vs. SHE where almost 39% of residual vinyl chloride VC was oxidized and the sulfate was formed back from sulfide further contributing to electric waste . http //www.sciencedirect.com/science/article/pii/S0045653514014271 Articolo in rivista Elsevier 0045 6535 Chemosphere Chemosphere Chemosphere Chemosphere. Chemosphere. Environmental chemistry, Chemosphere. Persistent organic pollutants and dioxins, Chemosphere. Environmental toxicology and risk assessment, Chemosphere. Science for Environmental toxicology, federico.aulenta AULENTA FEDERICO TA.P07.017.002 Processi Aerobici e di Dealogenazione Riduttiva per la rimozione dei contaminanti dalle acque |