Investigation of nickel-impregnated zeolite catalysts for hydrogen/syngas production from the catalytic reforming of waste polyethylene

Catalytic steam reforming of waste high density polyethylene for the production of hydrogen/syngas has been investigated using different zeolite supported nickel catalysts in a two-stage pyrolysis-catalytic steam reforming reactor system. Experiments were conducted into the influence of the type of zeolite where Ni/ZSM5-30, Ni/β-zeolite-25 and the Ni/Y-zeolite-30 catalysts were compared in relation to hydrogen and syngas production. Results showed that the Ni/ZSM5-30 catalyst generated the maximum syngas production of 100.72 mmol g‾¹ plastic , followed by the Ni/β-zeolite-25 and Ni/Y-zeolite-30 catalyst. In addition, the ZSM-5 supported nickel catalyst showed excellent coke resistance and thermal stability. It was found that the Y type zeolite supported nickel catalyst possessed narrower pores than the other catalysts, which in turn, promoted coke deactivation of the catalyst. Large amounts of filamentous carbons were observed on the surface of the Ni/Y-zeolite-30 catalyst from scanning electron microscope images. In addition, the influence of Si:Al molar ratio for the Ni/ZSM-5 catalysts in relation to hydrogen and syngas yield was inv estigated. The results indicated that hydrogen production was less affected by the Si:Al ratio than the type of zeolite support. Also, the Ni/ZSM5-30 catalyst was further investigated to determine the influence of different process parameters on hydrogen and syngas yield via different reforming temperatures (650, 750, 850 °C) and steam feeding rate (0, 3, 6 g h‾¹). It was found that increasing both the temperature and steam feeding rate favoured hydrogen production from the pyrolysis-catalytic reforming of waste polyethylene. The optimum catalytic performance in terms of syngas production was achieved when the steam feeding rate was 6 g h‾¹ and catalyst temperature was 850 °C in the presence of Ni/ZSM5-30 catalyst, with production of 66.09 mmol H 2 g‾¹(plastic) and 34.63 mmol CO gg‾¹(plastic)

Desenvolupament d'estratègies de comunicació per aconseguir "engagement" de les Generacions Z i Y amb la marca Patagonia a Espanya

Aquesta investigació acadèmica té com a objectiu aconseguir un major "engagement" per part de la Generació Z i la Millenial (Y) amb la marca Patagonia a Espanya a través d'estratègies de comunicació. Per aconseguir-ho, s'ha realitzat un estudi enfocat a la indústria de la moda sostenible a la marca Patagonia, i un estudi de la Generació Z i Millenial com a grups consumidors.Esta investigación académica tiene como objetivo conseguir un mayor "engagement" de la Generación Z y la Millenial (Y) con la marca Patagonia en España a través de estrategias de comunicación. Para conseguirlo, se ha realizado un estudio de la industria de la moda sostenible y la marca Patagonia, y un estudio de la Generación Z y Millenial como grupos consumidores. Posteriormente, se ha planteado la estrategia para lograr el objetivo.This academic research aims to achieve a greater engagement from the Z and Y Generations with the brand Patagonia in Spain through communication strategies. To achieve this, I have conducted a study of the sustainable fashion industry and the brand Patagonia, and a study of the Generations Z and Y as consumers. Subsequently, the strategy has been developed to achieve the objective

Deep UV photocatlytic activation of ethane on silica surfaces

Deep UV photolysis (165 or 185 nm) of surface silanol groups leads to the homolytic Osingle bondH bond breaking, generating silyloxyl radicals and hydrogen atoms. Silyloxyl radicals are able to activate ethane through hydrogen abstraction, whereby ethyl radicals are formed. Coupling of these ethyl radicals with silyloxyl radicals forms surface bound ethoxysilane that eventually will form ethanol. The product distribution of this radical process depends on the absence or presence of oxygen and may lead to the formation of ethanol together with light alkanes (methane, propane, butane and hexane) accompanied by C2 (acetaldehyde and acetic acid) and C1 (methanol, formaldehyde and formic acid) oxygenates. The presence of oxygen enhances ethane conversion and quenches the formation of alkanes by trapping alkyl radicals. It was found that micro and mesoporous silicas behave qualitatively similar with some differences in the product distribution. The most efficient material (higher conversion and higher percentage of products in the solid) was found to be Al-MCM 41. The energy consumption estimated based on a conversion of 6% on commercial beta zeolite was 2.0 Gcal per mol of ethane converted that is about 3.6 times smaller than the energy consumed form methane activation through an analogous process.We would like to express our most sincere gratitude to Prof. J.-M.-Herrmann that during all his career has been a guide and a reference for us in the field of photocatalysis. Financial support by the Spanish MICINN (Consolider Ingenio MULTICAT and CTQ2012-32315) is gratefully acknowledged.Sastre Calabuig, F.; Corma Canós, A.; García Gómez, H. (2012). Deep UV photocatlytic activation of ethane on silica surfaces. Applied Catalysis B: Environmental. 128:84-90. https://doi.org/10.1016/j.apcatb.2012.09.046S849012

On the Synergistic Catalytic Properties of Bimetallic Mesoporous Materials Containing Aluminum and Zirconium: The Prins Cyclisation of Citronellal

Bimetallic three-dimensional amorphous mesoporous materials, Al-Zr-TUD-1 materials, were synthesised by using a surfactant-free, one-pot procedure employing triethanolamine (TEA) as a complexing reagent. The amount of aluminium and zirconium was varied in order to study the effect of these metals on the Brønsted and Lewis acidity, as well as on the resulting catalytic activity of the material. The materials were characterised by various techniques, including elemental analysis, X-ray diffraction, high-resolution TEM, N2 physisorption, temperature-programmed desorption (TPD) of NH3, and 27Al MAS NMR, XPS and FT-IR spectroscopy using pyridine and CO as probe molecules. Al-Zr-TUD-1 materials are mesoporous with surface areas ranging from 700–900 m2 g−1, an average pore size of around 4 nm and a pore volume of around 0.70 cm3 g−1. The synthesised Al-Zr-TUD-1 materials were tested as catalyst materials in the Lewis acid catalysed Meerwein–Ponndorf–Verley reduction of 4-tert-butylcyclohexanone, the intermolecular Prins synthesis of nopol and in the intramolecular Prins cyclisation of citronellal. Although Al-Zr-TUD-1 catalysts possess a lower amount of acid sites than their monometallic counterparts, according to TPD of NH3, these materials outperformed those of the monometallic Al-TUD-1 as well as Zr-TUD-1 in the Prins cyclisation of citronellal. This proves the existence of synergistic properties of Al-Zr-TUD-1. Due to the intramolecular nature of the Prins cyclisation of citronellal, the hydrophilic surface of the catalyst as well as the presence of both Brønsted and Lewis acid sites synergy could be obtained with bimetallic Al-Zr-TUD-1. Besides spectroscopic investigation of the active sites of the catalyst material a thorough testing of the catalyst in different types of reactions is crucial in identifying its specific active sites