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The floating oil can drift to the coastal areas and interact with the shoreline substrates after oil spill accidents. This process is demonstrated to be the cause of the formation of oil-contaminated sediments, which has attracted much attention. However, no systematic study has concerned the desorption process of oil from oil-contaminated sediments when the coastal hydrodynamic conditions change. This work determines the effects of wave conditions and particle size on the release of oil from artificially prepared sediments in a wave tank. Nonlinear fitting results show that the oil release kinetic curves can be correctly estimated with the Lagrangian first-order (LFO) first-order equation. Under different test conditions. The oil concentration in the water increases rapidly within 6 h. However, the oil desorption is inhibited thereafter and the process of sorption occurs dominantly. Under higher wave energy, the process of desorption is significantly enhanced and more large oil droplets release from sediments. Under the same wave condition, small oil droplets firstly release from the sediments. Besides, more oil especially with a larger size can release from larger sediment while oil releases more quickly from smaller sediment.

[Display omitted] • Unamended river sediment generates 5 mW m−2 on unmodified C-cathode. • Oxygen reduction reaction was improved on MnO 2 /C surface. • Amended sediment with chitin generates 178 mW m−2 on modified MnO 2 /C-cathode. • Electroactive, degrader bacteria were identified on anode surface. Biodegradation of oil-contaminated sediments (OCS) in sediment microbial fuel cells (SMFC) is limited by several factors such as adapted microorganisms to degrade OCS, low conductivity and organic matter content, sluggish cathodic O 2 reduction reaction (ORR), among others. The use of a birnessite/Carbon Fabric (CF) cathode improves the O 2 reduction in SMFC. Oil-contaminated sediments amended with chitin (commercial analytical grade (CC) and dried natural shrimp shells (NC)) allows faster anaerobic biodegradation in the anolyte by the indigenous bacteria coming in the initial OCS, without further growth media. The SMFC containing the unmodified OCS produces a maximum power output of 5 mW m−2 in contrast to 62 mW m−2 and 178 mW m−2 of that SMFC containing CC and NC, respectively. High-power output of SMFC is the result of minimizing internal resistance by combining the following key factors: a) saturated air 0.8 M Na 2 SO 4 catholyte at pH 2, b) the use of a birnessite/CF-cathode, and c) the presence of bacterial groups enriched on the anode biofilm as Deltaproteobacteria and Bacteroidetes , additional to other groups such as Aminocenantia depending on the source of chitin. The pH of the catholyte strongly modifies the power production of SMFC; a detailed discussion is included in this paper. [ABSTRACT FROM AUTHOR]

The floating oil can drift to the coastal areas and interact with the shoreline substrates after oil spill accidents. This process is demonstrated to be the cause of the formation of oil-contaminated sediments, which has attracted much attention. However, no systematic study has concerned the desorption process of oil from oil-contaminated sediments when the coastal hydrodynamic conditions change. This work determines the effects of wave conditions and particle size on the release of oil from artificially prepared sediments in a wave tank. Nonlinear fitting results show that the oil release kinetic curves can be correctly estimated with the Lagrangian first-order (LFO) first-order equation. Under different test conditions. The oil concentration in the water increases rapidly within 6 h. However, the oil desorption is inhibited thereafter and the process of sorption occurs dominantly. Under higher wave energy, the process of desorption is significantly enhanced and more large oil droplets release from sediments. Under the same wave condition, small oil droplets firstly release from the sediments. Besides, more oil especially with a larger size can release from larger sediment while oil releases more quickly from smaller sediment. [ABSTRACT FROM AUTHOR]