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The encapsulation and delivery of drugs often involves the use of expensive microporous materials, and we have investigated the potential for natural zeolites from the widespread volcanic formations of southern Italy as alternatives to these carriers. Surface-modified natural zeolites (SMNZs) with diverse micellar structures (patchy and complete bilayers) were obtained by using different cationic surfactants [cetylpyridinium chloride (CP-Cl), benzalkonium chloride (BC-Cl), hexadecyltrimethylammonium chloride (HDTMA-Cl), and bromide (HDTMA-Br) with phillipsite-rich tuff from the Campania region (southern Italy)]. Loading and release kinetics tests of sodium ibuprofen (IBU) were carried out with organo-phillipsite composites using Fourier transform infrared spectroscopy (FTIR) and thermal analysis coupled with evolved gas analysis (EGA). Results from these tests were mathematically modeled to evaluate IBU adsorption and release mechanisms. The maximum loaded amount of IBU was attained for organo-phillipsite modified with HDTMA-Br (PHB), which showed a complete bilayer micellar structure. Whenever a patchy bilayer micellar structure formed, the lowest adsorptions of IBU were observed. Equilibrium adsorption results were fit using Langmuir, Sips, and Toth models. Pseudo-first-order and pseudo-second-order fits to the loading kinetic data provided significant goodness of fit. Good fits to the release kinetic data were obtained using first-order and Weibull equations, shedding new light on the release mechanism of IBU from phillipsite. The active amount of IBU on the modified zeolite surface was almost totally available for pharmaceutical purposes.

This paper focuses on the authigenic mineralization processes acting on “Tufo Rosso a Scorie Nere” (TRS), i.e. one of the main pyroclastic units of the Vico stratovolcano (Latium, Italy). The pyroclastic deposits appear in general massive and made of “black vitreous vesiculated juvenile scoriae”, immersed in an ashy matrix lithified after zeolitization processes. The main minerals are chabazite and phillipsite, and the zeolitic content is locally variable, reaching 68 % wt. Zeolites grow replacing both amorphous fraction and pre-existing phases, occurring inside both matrix and scoriae. Concerning scoriae, zeolitization moves from the rim to the core of the scoriaceous fragment as a function of (a) temperature of the fluids and (b) permeability (primary or secondary). Composition of parental fresh glass and that of zeolitized rocks is compatible with trachyte chemistry, lightly undersaturated in SiO2, and the alteration processes modified the parental rock chemical features. Zeolites genesis is ascribed to a “geoautoclave-like system”, and zeolites display a Si/Al ratio similar to that of the parental glasses. TRS presents promising mineralogical characteristics as supplementary cementitious material in the production of mixed cements.

GDS;VJ Tech, 4th European Conference on Unsaturated Soils, E-UNSAT 2020 -- 19 October 2020 through 21 October 2020 -- -- 164161, In soil stabilisation, the use of alternative products to lime or cement has been proposed. However, the effects of these additives, of various origins, on soil behaviour and stabilizing mechanisms are not well understood. Thus, the aim of this paper is to characterize the modification of the mechanical behaviour and microstructure of two soils after treatment with one of those product, a vinyl based copolymer. After treatment, both materials were compacted up to their maximum dry density. The mechanical behaviour of the materials as a function of the curing conditions, suction and water content was first determined. In a second step, the alteration of the microstructure by the treatment product was assessed. The results showed that the treatment permitted to significantly improve the strength of the tested soils. Moreover, the efficiency of the product increases when the soil is dried. However, the Young modulus is not significantly modified by the treatment. Microstructural reorganization after co-polymer addition has been detected by SEM technique for kaolin samples, whereas no modification have been observed for silt samples. © The Authors, published by EDP Sciences 2020., Horizon 2020 Framework Programme, H2020 H2020 Marie Sk?odowska-Curie Actions, MSCA: 778120, The project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 778120.

There is a growing concern on lightweight aggregates (LWA) for recycling of waste materials: this manufacturing technology is considered a flexible tool to make it possible the conversion of large amounts of residues into building products. The main challenge for this purpose is the control on the technological behavior during firing of waste-bearing batches. The target is engineering the sintering and expansion of LWA in order to tailor bulk density, mechanical strength and water absorption on various possible applications (e.g., structural and non-structural lightweight concretes, lightweight mortars, filtration substrates, floriculture). The prediction of the aggregate expansion - and hence the batch design - is usually carried out utilizing the Riley's and/or Cougny's schemes, which are based on the bulk chemical composition of clay bodies. However, collecting the literature data on waste-based LWA and plotting them in the Riley's and Cougny's diagrams, no reliable discrimination turns out between expanding and non-expanding batches. In the same way, the attempt to modify the Riley's and Cougny's parameters, including elements present in wastes but not in natural raw materials, was unsuccessful. From this standpoint, a new approach to assess the batch expandability was developed through a deeper comprehension of mechanisms acting on sintering and expansion of LWA. A specific characterization protocol was set up, entailing hot-stage microscopy and determination of phase composition and microstructure. This implies a paradigm shift from batch (chemical composition) to vitreous phase (amount, chemical composition, and viscosity at high temperature). The vitreous phase plays a key-role for bloating, microstructure and physical properties of LWA. A working example is presented about new LWA based on waste glasses, ceramic tile polishing sludge and clay raw materials. (C) 2016 Elsevier Ltd. All rights reserved.

The constant increase in consumption of aggregates for concrete production represents a major environmental issue in the construction industry. Recycled wastes might be used as raw materials in the manufacturing of artificial LightWeight Aggregates (LWAs) in substitution and/or in combination with aggregates produced using natural sources for several end-uses, thus saving non-renewable resources. In this study, a Life Cycle Assessment (LCA) is performed for different LWAs manufactured with raw materials supplied by nature or waste. Then, the LCA is conducted on different concretes made of the different LWAs. (C) 2016 Elsevier Ltd. All rights reserved.