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Several Ni catalysts of supported (on La 2 O 3 -αAl 2 O 3 , CeO 2 , and CeO 2 -ZrO 2 ) or bulk types (Ni-La perovskites and NiAl 2 O 4 spinel) have been tested in the oxidative steam reforming (OSR) of raw bio-oil, and special attention has been paid to the catalysts' regenerability by means of studies on reaction-regeneration cycles. The experimental set-up consists of two units in series, for the separation of pyrolytic lignin in the first step (at 500 • C) and the on line OSR of the remaining oxygenates in a fluidized bed reactor at 700 • C. The spent catalysts have been characterized by N 2 adsorption-desorption, X-ray diffraction and temperature programmed reduction, and temperature programmed oxidation (TPO). The results reveal that among the supported catalysts, the best balance between activity-H 2 selectivity-stability corresponds to Ni/La 2 O 3 -αAl 2 O 3 , due to its smaller Ni 0 particle size. Additionally, it is more selective to H 2 than perovskite catalysts and more stable than both perovskites and the spinel catalyst. However, the activity of the bulk NiAl 2 O 4 spinel catalyst can be completely recovered after regeneration by coke combustion at 850 • C because the spinel structure is completely recovered, which facilitates the dispersion of Ni in the reduction step prior to reaction. Consequently, this catalyst is suitable for the OSR at a higher scale in reaction-regeneration cycles.

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Auxiliary Tanabe–Sugano diagrams are presented. They enable a rapid and reliable graphical derivation of Dq/B and C/B crystal field parameter ratios from spectroscopic data. Using these values, one can calculate Dq and B by employing the original Tanabe–Sugano diagrams. Subsequently, C can also be calculated irrespective of the value C/B fixed in the Tanabe–Sugano diagram.

The research for new energy sources has promoted hydrocarbon production from biomass and solid wastes over ZSM-5 zeolites. The metal incorporation by different methods has led to a variety of chemical applications. In this way, the combination of the shape selectivity and acidity properties of the pentasil zeolites with the activity of metal oxide under different environments may influence the product distribution in diverse catalytic reactions. In this work, ZSM-5 zeolites were prepared by hydrothermal synthesis employing aluminum nitrate and AIP as aluminium sources and TPAOH as structure director agent at atmospheric pressure and low temperature (90 °C). In addition, these materials were modified with iron and titanium cations by direct synthesis at 170 °C and autogenous pressure to promote the crystallinity. The characterization of the samples was performed by XRD, XRF, SEM, TPD-NH3 and nitrogen adsorption. It was observed that the use of AIP and the metal incorporation decreases the crystallinity of the zeolites under synthesis conditions, which leads to increase the specific area value in the BET because of the presence of amorphous material. On the other hand, acidity of the modified zeolites was found to be lower than that of ZSM-5 zeolite.

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Actualmente se realizan investigaciones a nivel mundial para desarrollar nuevos materiales con propiedades adecuadas para la fabricación de dispositivos fotovoltaicos, con el fin de obtener energía de fuentes renovables y reemplazar las convencionales. Por motivos ambientales los materiales deben ser abundantes y no ser contaminantes, requisitos que el sulfuro de zinc (ZnS) cumple. En este estudio se sintetizaron películas delgadas de ZnS por el método sol-gel para evaluar el efecto de algunos precursores de zinc y azufre, de los agentes complejantes, así como del tratamiento térmico a 500 °C en la obtención del ZnS.  os sólidos obtenidos y tratados en atmósfera oxidante se caracterizaron mediante difracción de rayos-X (XRD), lo que permitió establecer el protocolo de reacción más adecuado para la preparación del ZnS y depositar recubrimientos de ZnS sobre sustratos de vidrio-cuarzo usando la técnica de recubrimiento por centrifugación (spin coating). Las películas también se sometieron a un tratamiento térmico basado en nitrógeno gaseoso y azufre elemental. Los recubrimientos de ZnS se caracterizaron con XRD, microscopía electrónica de barrido (SEM), espectroscopía dispersiva de rayos X (EDS) y espectroscopía UV-Vis. Los resultados evidenciaron que las películas depositadas presentan propiedades adecuadas para ser empleadas como capa amortiguadora en celdas solares.

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