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The electrochemical oxidation of an effluent from the manufacture of phosphorus based flame retardants was studied. To reach a residual concentration of reduced phosphorus lower than 10 mg L-1, in compliance with Italian law for industrial wastewater disposal, anodic oxidation using a boron-doped diamond (BDD) anode and electro-Fenton (EF) treatment were tested. The effects of some factors are optimised and a comparison of the reaction pathways is also presented. A combined treatment using EF with BDD conducted in an undivided cell is shown not to enhance the data obtained with BDD while a novel combined treatment using EF and BDD in a divided cell shows promising results when an anionic membrane is used as separation. In this last case the cell operates as two different batch reactors working with the same current. The anodic compartment, fed with raw effluent, provides partial oxidation, while the cathodic compartment, fed with the partially anodically oxidised solution, completes the treatment. When the effluent is transferred in the cathodic compartment, the anodic one is fed with fresh untreated solution. The advantage of this kind of coupling consists in the simultaneity of the two treatments which allows total oxidation with notable saving of charge and time

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To construct a new tourist harbour in Marina di Ragusa (Sicily), the dredging of 300,000 m 3 of marine sediment is required. To evaluate potential disposal options, a detailed physico-chemical characterisation of this material is needed. A very cost-effective solution is represented by the re-use of the dredged material for beach nourishment. To this aim, compliance with environmental standards and a strong homogeneity between the receiving beach and the source sediments must be proved. Analytical determinations for the main parameters show an arsenic content exceeding the Italian quality standard (12 mg·kg −1 ). In order to evaluate arsenic mobility and availability, and therefore the actual release into the environment, a three-step sequential extraction procedure was applied to a limited number of samples. The results obtained seem to exclude the risk, showing that arsenic is almost totally bound to the resistant fraction and thus does not represent an impediment to the beneficial re-use of sediment.

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