Electrokinetic experiments have been performed on a natural soil artificially contaminated with gasoil. 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. In addition, most organic contaminants are nonionic and therefore, they are not mobile under electrical field. The use of surfactants may increase the remediation efficiency by increasing the solubility of organics. Some surfactants, known as biosurfactants since produced by yeast or bacteria, has been studied extensively like complexing and environmental friendly agent. 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 (biosurfactant). Electrokinetics experiments were undertaken on a gasoil contaminated soil (~ 20000 ppm). Graphite carbon electrodes were used to provide an electrical direct current (ddp 30 V). Rhamnolipid was applied on the contaminated soil at various concentrations, while 1N citric acid was used as purging solution in both cathode and anode compartment. pH, conductivity and ddp were measured daily in the electrolyte solutions in order to control the process. Results shows 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.
Electrokinetic remediation of gasoil contaminated soil enhanced by rhamnolipid / DI PALMA, Luca; Gonzini, Ornella; A., Plaza; M. C., Lobo Bedmar. - STAMPA. - A:(2009), pp. 14/1-14/6. (Intervento presentato al convegno 2nd International Conference on Polluted Sites Remediation, Bosicon 2009 tenutosi a Roma nel 13-15 Maggio 2009).
Electrokinetic remediation of gasoil contaminated soil enhanced by rhamnolipid
DI PALMA, Luca;GONZINI, ORNELLA;
2009
Abstract
Electrokinetic experiments have been performed on a natural soil artificially contaminated with gasoil. 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. In addition, most organic contaminants are nonionic and therefore, they are not mobile under electrical field. The use of surfactants may increase the remediation efficiency by increasing the solubility of organics. Some surfactants, known as biosurfactants since produced by yeast or bacteria, has been studied extensively like complexing and environmental friendly agent. 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 (biosurfactant). Electrokinetics experiments were undertaken on a gasoil contaminated soil (~ 20000 ppm). Graphite carbon electrodes were used to provide an electrical direct current (ddp 30 V). Rhamnolipid was applied on the contaminated soil at various concentrations, while 1N citric acid was used as purging solution in both cathode and anode compartment. pH, conductivity and ddp were measured daily in the electrolyte solutions in order to control the process. Results shows 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.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
