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Abstract: This paper presents the results obtained by replacing German and Ukrainian clays in a porcelain stoneware body with a clay from Sardinia island, Italy, added with 10wt% of different bentonites available on Italian territory in order to lower the body costs. Two series of bodies were prepared: a first series by substituting completely German clay and partially Ukrainian clay (5wt%) and a second series by substituting completely the Ukraine clay. Rheological measures were carried out on the suspensions prepared in order to verify the effect of the bentonites presence on the shear and time dependence. The fired specimens were characterized across the technological parameters (water absorption, linear shrinkage, etc.), mechanical and aesthetical properties and compared with a standard/industrial composition. [Copyright &y& Elsevier]

In Italy, the production of bottom ash from waste incineration was estimated as 1.6 million tons/year, corresponding to 30% of the total input waste. The bottom ash is mainly formed by SiO 2 , Al 2 O 3 , CaO, Na 2 O and low amount of heavy metals, therefore it cannot be considered a 'non-hazardous' waste. In this context, the aim of this work was to determine the effectiveness of the sintering and vitrification techniques to turn bottom ash into an inert ceramic or glass matrix using toxicological tests. The bottom ash from a municipal solid waste facility was ground and used in ceramic tile and glass compositions. After sintering of the ceramic tiles and melting of the glass compositions, the samples were characterized by leachability and toxicological analyzes. Living organisms were used in the toxicological tests, Escherichia coli and Staphylococcus aureus (Agar Diffusion Test), Artemia sp. (Acute Toxicity Test) and Lactuca sativa (germination) and the results were compared with the plasmid DNA test. Regarding the leachability results, the ceramic tile samples showed a concentration of Cu slightly above the limit determined by the D.M. 5/4/2006 directive and, therefore, could not be considered an inert material. Regarding the toxicological tests, the bottom ash alone is mutagenic, but this effect is avoided once the ash is immobilized into the glasses and ceramic tiles, as demonstrated by the results reported in this study., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

In this study the use of 'cleaned' end of life (EOL) cathode ray tube (CRT) glass as a raw material in ceramic glazes is described. At present, the recycling and industrial utilization of CRT, a glass material from TV and computer sets, is a subject of intense research with particular regard to the so-called open-loop recycling, namely cycles different from that of the origin. However, the use of CRT glass as a secondary raw material is strictly related to the demand of high-quality raw material. The good preliminary results reached by introducing clean TV and PC monitor panel and cone glass into ceramic glaze formulations pushed research toward the setting-up of a base glaze that is exploitable for the production of pigmented, silk-screened and flame-hardened glazes (products used industrially for coating floor tiles). The aesthetic and chemical characterization of the tiles glazed by this product showed an extremely similar behaviour to originals that did not contain CRT glass. The good technical results achieved have been supported by the life cycle assessment analysis, which has demonstrated a reduction of the environmental impact of the CRT glass-containing ceramic glaze with respect to the standard one.