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It has studied the solubility process of four different waste glasses (with different particle sizes, <45 µm and>125 µm) in alkaline solutions (NaOH and NaOH/Na 2 CO 3 ) and water as a reference and under different conditions of solubility (at room temperature, at 80°C and a mechano-chemical process). Have established the optimal conditions of solubility and generation of sodium silicates solutions, and these were: the smaller particle size (<45 µm), with NaOH/Na 2 CO 3 solution and with temperature during 6 hours of stirring time. The statistical analyses of the results give importance to the studied variables and the interactions. Through 29 Si NMR MAS it has confirmed the formation after dissolution processes of monomeric silicate, suitable for use as an activator in the preparation of alkaline cements and concretes. RESUMEN: Disoluciones de silicato sódico procedentes del tratamiento de residuos vítreos Estudio estadístico.Se ha estudiado el proceso de solubilidad de cuatro diferentes residuos vítreos (con distintas granulometrías, <45 µm y >125 µm) en disoluciones alcalinas de NaOH y NaOH/Na 2 CO 3 y agua como medio de referencia y bajo distintas condiciones de solubilidad (a temperatura ambiente, a 80°C y con un proceso mecano-químico). Se han establecido las condiciones óptimas de solubilidad y generación de disoluciones de silicato sódico, y estas son: menor tamaño de partícula del residuo vítreo (inferior a 45 µm), con la disolución de NaOH/Na 2 CO 3 y tratamiento térmico a 80°C durante 6 horas de agitación. El análisis estadístico realizado a los resultados obtenidos da importancia a las variables estudiadas y a las interacciones de las mismas. A través de 29 Si RMN MAS se ha confirmado la formación, tras los procesos de disolución, de un silicato monomérico, apto para su utilización como activador en la preparación de cementos y hormigones alcalinos.

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Activated carbons have been prepared by the chemical activation of olive stones with phosphoric acid and loaded with Zr. The addition of Zr to the phosphorus-containing activated carbons resulted in the formation of zirconium phosphate surface groups. Gas phase methanol dehydration has been studied while using the prepared Zr-loaded P-containing activated carbons as catalysts. Carbon catalysts showed high steady-state methanol conversion values, which increased with Zr loading up to a limit that was related to P content. The selectivity towards dimethyl ether was higher than 95% for all Zr loadings. Zirconium phosphate species that were present on catalysts surface were responsible for the catalytic activity.

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The use of carbon-based materials as catalyst supports for Fischer–Tropsch synthesis (FTS) is thoroughly reviewed. The main factors to consider when using a carbonaceous catalyst support for FTS are first discussed. Then, the most relevant and recent literature on the topic from the last 2 decades is reviewed, classifying the different examples according to the carbon structure and shape. Some aspects such as the carbon textural properties, carbon support modification (functionalization and doping), catalyst preparation methods, metal particle size and location, catalyst stability and reducibility, the use of promoters, and the catalyst performance for FTS are summarized and discussed. Finally, the main conclusions, advantages, limitations, and perspectives of using carbon catalyst supports for FTS are outlined.