Electrokinetic remediation (EKR) has been investigated as one of the best technologies in soil remediation but its applications for organic contaminants have been limited due to low solubility of organics in water and their non-ionic nature. The use of biosurfactants may increase the remediation efficiency by increasing the solubility of organics. The purpose of the introduction of complexing substances is to enhance the EKR process forming complexes and/or increasing the electro-osmotic flow. In this study, the removal of gasoil from a soil using electrokinetic method was investigated in the presence of Rhamnolipid at various concentrations. EKR experiments were undertaken on a gasoil contaminated soil (20,000 ppm). Graphite carbon electrodes were used to provide an electrical direct current (ddp 30-60 V). Results showed that increasing the dose of Rhamnolipid, the efficiency of gasoil removal increased up to 86.7%. Moreover, the lower concentration of the gasoil observed in the liquid phase at the higher concentration of the biosurfactant clearly indicated that the Rhamnolipid addition can enhance gasoil biodegradation

This study presents the results of laboratory-scale experimental tests of contaminant extraction from marine sediment slurries. The sediment was collected in a harbour situated in a high-density industrial area, characterised by a high pollution level of heavy metals. The objective of this study was to investigate the effectiveness of selected chelating agents (rhamnolipids, EDDS, EDTA and citric acid) in heavy metal removal from contaminated sediments. To this aim, contamination of the sediment used in this experiment was artificially increased to reach final values of 1250 mg·kg-1 Cu and 2026 mg·kg-1 Pb. The investigated parameters during the washing tests were chelant concentration and overall washing time. To evaluate the sediment characteristics, COD and acid digestion were performed, whereas total organic carbon and heavy metal concentration were determined on the solutions extracted. The results show that the use of EDDS and EDTA gave good extraction efficiencies (up to 95%), unlike the lower removal rates achieved by using citric acid and rhamnolipids. In addition, major cations, mainly Fe and Ca, were found to be strong competitors with the target metals for metal-ligand complex formation. © 2011 Taylor & Francis

This study presents the results of laboratory experimental oxidation treatments conducted on marine sediments highly polluted with hydrocarbons. The purpose of the study was to compare the effect of a modified Fenton treatment conducted with acidified stabilised H2O2 with one of simple acidification with H2SO4 used as control to evaluate the potential of heavy metal mobilisation. The H2O2 initial concentration was 0.62M and KH2PO4=1.15g center dot L-1. To evaluate changes in the solid and liquid phase, chemical oxygen demand (COD), thermogravimetric analysis (TGA) and differential thermal analysis (DTA) under O2 atmosphere analyses were performed on the solid, while total organic carbon (TOC), COD, pH and Eh were measured on the liquid. Evaluation of the heavy metal mobilisation was performed using sequential extraction procedures. Results indicate that the treatment was able to change the organic matter to a less hydrophobic state, to destroy part of the carbon and to lower the COD of the sediment. In addition, the treated sediment showed easier-to handle characteristics, reduced caking and lower aggregation capacity. However some mobilisation of Cu occurred while the concentration of Fe lowered

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