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Contamination of marine sediments by polycyclic aromatic hydrocarbons (PAHs) poses a significant environmental threat, necessitating effective remediation strategies. This paper investigates the application of surfactants, both synthetic and natural, for the remediation of PAH-contaminated sediments, providing a systematic guideline for the preliminary selection of surfactants for flushing/washing operations, the optimal operative conditions, and the technical approach for PAH mobilization, especially in the context of a real aged contamination scenario. The study included a batch configuration test to evaluate the effect of surfactant concentration on PAH mobilization. Subsequently, a continuous configuration column experiment was performed to simulate a flushing operation of contaminated sediment. The study of process conditions highlighted that the increase in surfactant concentration led to a significant increase in PAH removal from the sediment, reaching almost 30 % efficiency using a 5 % wt surfactant solution. The column test showed great efficiency of the investigated surfactants in PAH mobilization through the flushing process of the contaminated matrix, resulting in 30 times greater efficiency than water within a much smaller pore volume range. • A polluted marine sediment with highly recalcitrant compounds from an Italian National Priority Site was used for the study. • Sediment chemical characterization showed the presence of 16 different PAHs with a total concentration equal to 3.51 g Kg −1. • Column experiment were performed to simulate a sediment-flushing operation as a novel strategy to remediate polluted matrix. • Surfactants senhanced PAHs mass transfer from the sediment to the aqueous phase in a very small pore volume range. • Continuous configuration process led to a greater PAHs removal than the more traditional batch configuration sediment washing. [ABSTRACT FROM AUTHOR]

This study investigates the performance of two non-ionic sugar-based surfactants, belonging to the families of synthetic alkylpoliglucosides and biological rhamnolipids, for enhancing the solubilization and mass transfer of strongly adsorbed hydrophobic organic compounds (HOCs) in porous media. Using toluene and perchloroethylene (PCE) as reference pollutants, a continuous configuration test (column experiment) was performed to simulate a soil flushing process under controlled laboratory conditions. The potential applicability of the selected surfactants in remediation processes was evaluated within the context of Surfactant Enhanced Aquifer Remediation (SEAR) technology. Experimental results showed that both surfactants effectively increased the solubilization of contaminants adsorbed on porous media. Compared to H 2 O flushing, synthetic surfactant increased the solubilization of toluene by 52% and the solubilization of PCE by 81%, while biosurfactant increased solubilization ability by 73% and 92% for toluene and PCE, respectively. Biosurfactant exhibited the greatest solubilization ability, with 92% of adsorbed toluene and 98% of adsorbed PCE solubilized. This research highlights the potential of green surfactants as efficient candidates for remediation processes due to their excellent solubilization ability and environmentally friendly nature. [Display omitted] • Non-ionic sugar-based green surfactants for contaminants solubilization. • Simulation of soil flushing process in bench scale through laboratory column test. • Solubilization abilities of selected surfactants are evaluated. • Solubilizing performances of synthetic surfactants and biosurfactants are compared. [ABSTRACT FROM AUTHOR]