Municipal Solid Waste incinerator residues produced in two types of facilities were exhaustively characterized: granulometry, mineralogy, chemical composition, leaching behavior, and elemental distribution as a function of particle size. Air Pollution Control (APC) residues coming from a semi-dry scrubber have shown higher solubility than fly ashes originating in an Electrostatic Precipitator (ESP), as well as higher contents in volatile metals (Cd, Hg). Different metal speciation and distribution as a function of particle size have been found in fly ashes (ESP residues) and APC residues. In APC residues, heavy metals (with the exception of Hg) show a parabolic distribution with maxima in the smallest and largest particles, following the same profile as soluble salts. Metal distribution for APC residues exhibits that metals generally are not associated with silicate aluminate matrix. Results show the effect of adding lime to APC residues in metal speciation and distribution. INTRODUCTIONMunicipal Solid Waste Incineration (MSWI) is an integrated waste management system. MSWI offers a reduction in both the mass and volume of waste subjected to final disposal, as well as the possibility of energy recovery; waste mass is reduced approximately 70%, and volume by about 90%, and it provides energy that can be recovered to produce electricity or steam.

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ABSTRACT:The curing process was studied for a trifunctional epoxy resin, triglycidyl-p-aminophenol, using the hardener 4,4Ј-diaminodiphenylsulfone. Two curing cycles were carried out: one following the manufacturer's guidelines (2 h at 80°C, 1 h at 100°C, 4 h at 150°C, and 24 h at 200°C) and another proposed in this study, in which the two stages at low temperatures were excluded. Fourier transform IR spectroscopy was used to quantify the conversion of different functional groups (primary amine, secondary amine, epoxide, hydroxyl and ether functional groups), and these conversions could be used to infer the type of reactions that took place. These results allowed us to analyze the evolution of the curing process over time and the influence of the curing cycle. Furthermore, the enthalpy of the curing process was determined using differential scanning calorimetry, and from this the thermal conversion for the whole process was evaluated. By taking into account the autocatalytic kinetic model, the rate constants were evaluated. The glass-transition temperatures were also estimated by applying different curing cycles to the resin.

A study was conducted on the curing process of a nanocomposite consisting of a trifunctional epoxy resin, a hardener containing reactive primary amine groups, and montmorillonite (MMT) nanoparticles, previously treated with octadecyl ammonium. Three levels of MMT content were used: 2, 5, and 10%. The curing was carried out following the cycle: 4 h at 1008C, 2 h at 1508C, and 2 h at 2008C. Isothermal trials were also considered at three levels (120, 150, and 2008C) to conduct a kinetic study. The curing conversion was determined by FTIR spectroscopy by selecting the suitable bands for epoxide and primary amine functional groups. The study demonstrated that the MMT nanoparticles accelerate the curing process, especially at the initial stages of the thermal cycle, being this influence quasi negligible at the end of the cycle. Curing conversions were also evaluated by differential scanning calorimetry and compared to those obtained by FTIR spectroscopy.