Sulfidic copper−lead−zinc tailings can pose a significant environmental threat, ranging from generation of acid mine drainage (AMD) to dam failures. On the other hand, they can also be considered as low-grade ore resources for zinc and copper provided that novel economically feasible metal extraction and metal recovery techniques are developed. Due to the low metal concentrations in these resources, the leaching will generate dilute leachates from which metal recovery is a challenge. Ion flotation is a foam separation technique capable of recovering metal ions from dilute aqueous leachates. In this paper, ion flotation was applied to separate copper from ammoniacal leachates of microwave-roasted sulfidic tailings samples. The sulfidic tailings were first roasted at 550 °C for 60 min, for the oxidation of sulfide minerals to more easily soluble sulfates using microwave assisted irradiation as heating source. The microwave-roasted material was then leached with a mixture of ammonia and ammonium carbonate solutions. The optimum leaching efficiencies of zinc (86%) and copper (75%) were obtained under the following conditions: liquid-to-solid ratio = 10 mL g -1 , T = 90 °C, [NH3+NH4 + ] = 4 mol L -1 , NH3:NH4 + = 2:1, t = 5 h. From the generated pregnant leach solution, it was possible to selectively separate 85% of copper to the foam phase by ion flotation, with sodium dodecyl sulfate (SDS) surfactant, as colloidal tetraammine copper(II) dodecyl sulfate under the optimized conditions: [SDS]total = 5.85 mmol L -1 , [EtOH] = 0.5 % (v/v), ttotal = 5 h, flotation stages = 3. The zinc that remained in the solution after ion flotation was recovered by precipitation (95%) as basic zinc carbonate.

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The island of Kythira in Greece suffered a major forest fire in 2017 that burned 8.91% of its total area and revealed many challenges regarding fire management. Following that, the Hellenic Society for the Protection of Nature joined forces with the Institute of Mediterranean and Forest Ecosystems in a project aiming to improve fire prevention there through mobilization and cooperation of the population. This paper describes the methodology and the results. The latter include an in-depth analysis of fire statistics for the island, development of a forest fuels map, and prevention planning for selected settlements based on fire modeling and on an assessment of the vulnerability of 610 structures, carried out with the contribution of groups of volunteers. Emphasis was placed on informing locals, including students, through talks and workshops, on how to prevent forest fires and prepare their homes and themselves for such an event, and on mobilizing them to carry out fuel management and forest rehabilitation work. In the final section of the paper, the challenges that the two partners faced and the project achievements and shortcomings are presented and discussed, leading to conclusions that can be useful for similar efforts in other places in Greece and elsewhere.

Extraction of copper, lead and zinc from photovoltaic panel residue by microwave-assisted chloride leaching, followed by recovery of extracted metals from the pregnant leaching solution by cementation, ion flotation and precipitation.