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The correct management of municipal solid waste (MSW) is a critical factor in the protection of the environment, as well as a source for the recovery of valuable materials for a circular economy. The Principality of Asturias and the Region of Prague has developed a comprehensive waste management system for the correct treatment of the waste generated, to achieve also the recycling targets set by European policies. The research compares the generation and management policies in both regions. The influence of several characteristics such as the collection of MSW, population density, type of municipality, and presence of different waste disposal facilities was also analysed. As was expected, the presence of an extensive system of civic amenity sites and bulky facilities decreases the volume of mixed municipal waste disposed of, and apparently improves the recycling rate. On other hand, and on contrary to popular belief, the utilisation of MSW incineration systems and ash management, like in Prague, improves recycling rates.

Bio-derived magnetic activated carbons from industrial chestnut shell waste have been obtained through a novel, optimized and sustainable methodology where impregnation, pyrolysis, acid washing or other intermediate steps commonly used in the activation process were eliminated saving time, energy and costs. The resulting materials (MACs) were obtained at 220-800 °C showed interesting properties: textural (SBET up to 568 m2 g-1) and magnetic (different iron species developed), depending on the activation temperature employed. Data showed outstanding results when MACs were tested for Hg removal in pollution emissions at 150 °C in lab-scale device. In MACs obtained at 500-600 °C, where the highest concentration of magnetite was found, the best Hg adsorption capacity was achieved, while it decreased when metallic iron or iron carbides were present (MACs obtained at 800 °C). Moreover, the difference of Hg0 removal/adsorption in N2+O2 and Simulated Flue Gas atmosphere between MACs obtained at 500 and 600 °C pointed out the influence on Hg removal of additional parameters, as surface chemistry and the existence of sulfur or chloride. The determination of Hg species in post-retention solids confirmed the mercury oxidation by high-valence iron ions (Fe3+) and the involvement of physisorption and chemisorption processes for the gas-solid interaction mechanism.

A novel type of carbon fibers, obtained by direct chemical activation of stabilized fibers (non-carbonized), is investigated as active electrode material in supercapacitors (SCs). The main advantage of this novel synthetic method is that it avoids the step of carbonization of the stabilized fibers prior to activation, reducing therefore their cost of production. The as-obtained materials exhibit specific capacitances up to 100 F g-1 in aqueous electrolytes (1.0 M H2SO4), values that are not only higher than those obtained with conventional fibers but also comparable to the capacitances of SCs based on well-established reference materials such as commercial activated carbons (ACs). © 2014 Published by Elsevier B.V.