Artículos SCI

The Alcazar Palace (Seville, Spain) is famous for its ceramic decorations; 16th century wall tiles of different typologies have been analyzed in order to relate the manufacturing process of their colored glazes to the evolving technologies of the Renaissance. Chemical and mineralogical compositions have been determined in situ by nondestructive X-ray fluorescence and X-ray diffraction on arista ceramics in the Cenador de Carlos Quinto, and majolica ceramics in the Palacio Gotico and the Royal oratory. The arista style belongs to the local Hispano-Moresque ceramic tradition. Majolica tiles have the complex microstructures of glazes from Italy. The two types are clearly differentiated by their typology, morphology (curved vs flat surface), and also microstructure (single vs multi-layers), glaze chemistry, and use of different coloring agents. Moreover, we found different glaze chemistries in the investigated majolicas, which correspond to different artists and/or practices.

The copper-impregnated pyrophyllite (Cu/RC) was prepared and used as catalyst in catalytic wet peroxide oxidation (CWPO) of phenol. The catalyst was prepared by impregnation of copper (2.5 wt%) into pyrophyllite-type clay and characterized by X-ray diffraction, X-ray fluorescence, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and transmission electron microscopy. The optimum operation conditions for CWPO of phenol over Cu/RC were determined by investigating the effects of pH, temperature, catalyst amount, and hydrogen peroxide concentration. Stability of the Cu/RC catalyst and toxicity of treated solution were studied, by measuring the copper concentration leached out from the catalyst and the inhibition of Vibrio fischeri bacteria bioluminescence, respectively. The probable degradation mechanism of phenol over Cu/RC was considered by HPLC analysis. The obtained results showed that Cu/RC achieved highest activity (total phenol degradation and 80% TOC reduction) and detoxification with remarkable low copper leaching concentration (0.006 mg\,L−1)mg\,L−1) at optimized conditions (pH == 3, T=50∘T=50∘C, 2 g\,L−1g\,L−1 catalyst amount, 50 mg L−1L−1phenol concentration and 7.45 mmol\,L−1mmol\,L−1 hydrogen peroxide concentration during 4 h). Meanwhile, few intermediates with low concentration were observed by the HPLC analysis for the CWPO of phenol. The Cu/RC catalyst showed a good activity after five successive runs (88% of degradation and 73% mineralization) at optimized conditions.