Sugarcane bagasse ash (SCBA) is an industrial waste that contains silicon and aluminum oxides as the major components and iron, calcium, magnesium, and potassium oxides as the main minor components. In this paper, SCBA from one Brazilian factory was characterized and tested for its influence on the ceramic properties of clay/ash ceramic probes. Prismatic probes were pressed (18 MPa) using a ceramic mass mixed with 0%, 5%, 8%, and 10% ash. The probes were fired at temperatures between 800° and 1200°C. X‐ray diffraction, X‐ray fluorescence, thermal analysis (differential thermal analysis, thermogravimetric analysis/differential thermogravimetric analysis), and tests for texture (particle‐size analysis), flexural strength, and linear shrinkage were carried out to characterize the samples. The results showed that the amount of ash to be incorporated will depend on mainly the composition of clay but also ash, and indicated that the clay used in this work can incorporate up to 10% weight of ash to produce solid bricks. The results also showed an improvement in ceramic/ash properties up to sintering temperatures higher than 1000°C.

The refrigeration industry produces millions of tons of waste polyurethane (PU) every year, which can cause environmental damage and human health problems. This article analyzes the use of waste PU as filler in composites made of styrene butadiene rubber (SBR) and natural rubber (NR) to produce shoe soles. The interfacial interaction of said filler was evaluated by the Flory-Rehner method (swelling) using the equation developed by Lorenz-Park. The results of this evaluation were later compared with those obtained by the Mooney-Rivlin method using the data from stress-strain tests. According to the results of the tensile strength tests, the composites filled with waste PU present stress-strain curves that are like those of metallic materials that have low elastic strength but high plastic strength. Using the Lorenz-Park equation, the filled composites examined in this study exhibited values above 0.7, which means a strong filler-rubber interaction. Scanning Electron Microscopy and Fourier-Transform Infrared Spectroscopy were used to investigate the morphology of the composites in detail.

Solid waste from disposable long neck bottles was used as pozzolanic additive to the cement matrix. Mortar specimens containing finely ground glass (90-53 µm) until 15 wt% were evaluated for physical and mechanical properties. The mechanical test showed an increase of 97% (greater than the values found in the literature) in the axial compression strength of the samples containing glass due to the increased pozzolanic activity index caused by glass addition to mortar. The mechanical strength was relatively greater when the glass particle size was reduced (53-38µm). The pozzolanic activity was observed at advanced ages either, by Brazilian standardized tests or thermal reactions between water and calcium hydroxides. Scanning electron microscopy reinforced the hydrated-calcium silicates present after calcium hydroxide consumption, characteristic of pozzolanic materials. From a technical and environmental viewpoint, the use of glass waste from long neck bottles as pozzolanic additive to the cement matrix proved to be feasible.

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Glass-ceramic materials were obtained by heat treatment (960 ºC for 2, 4, and 6 hs) of glasses with CaCO 3 47.50 wt%-TiO 2 23.75 wt%-SiO 2 23.75-Al 2 O 3 5.00 wt% formulation produced by the melt-quenching technique (melting at 1650 ºC and subsequent annealing at 650 ºC). The materials' structural characterization and crystallization kinetics (Kissinger method) indicate the presence of CaTiO 3 , CaSiO 3, and CaTiSiO 5 crystalline phases with activation energies 217, 281, and 446 kJ/mol, respectively. The structure refinement (Rietveld method) suggests metastability for the CaSiO 3 and CaTiSiO 5 phases as a function of the heat treatment time. The increase in time favors CaTiO 3 crystallization, from 62.97 wt%, in the 2 hs treated sample, to 79.21 wt%, in the 6 hs treated sample. EDS and microstructure analyses confirm the glass-ceramic production and indicate segregation of the CaTiO 3 phase for longer heat treatment times.