A kinetic study for dry reforming of methane over Ni-Ce/Al 2 O 3 catalyst was performed, taking into account both the main reactions and the catalyst deactivation. The catalyst was prepared by a sequential wet impregnation process, with loadings of 5 wt.% Ni and 10 wt.% Ce. Experimental tests were carried out in a fixed bed reactor between 475 and 550 °C and several spatial times, using nitrogen as diluent. Several kinetic equations were compared. The best fit of experimental data was achieved using a Langmuir-Hinshelwood mechanism which takes into account the presence of two active sites. Preexponential factor and activation energy were calculated. the kinetics of deactivation was also determined. The relationship between catalyst activity and coke concentration was also studied. Several deactivation equations were considered in order to choose the best fit with experimental data.
Coal combustion residuals (CCR) are waste products generated during the operation of coal-fired electric power stations, but the effect of CCR inclusions on the deterioration of road infrastructure at or near power plants remain uncertain. This study measured the resilient modulus (M r ) of low-plasticity clay (FS) mixtures with different proportions of CCR obtained from a coal-fired power station, without any additional cementitious substances or stabilizers. Resilient moduli were determined for both the raw materials (FS and CCR) and for mixtures ranging between 10% and 40% CCR by weight. All materials were characterized physically, chemically, and mineralogically. Resulting physical and mechanical-behavior parameters were compared across the CCR content range, specifically the change in index properties, USCS classification, maximum dry density, and resilient-modulus degradation. Results highlight the strong dependence of the soil's resilient moduli on water content due to the inherent partially-saturated character of the material.
ResumenLos residuos producto de combustión de carbón (RPCC) se generan en plantas termoeléctricas, pero el efecto de la contaminación por RPCC en el deterioro de la infraestructura vial en inmediaciones de dichas plantas es incierto. Este estudio midió el efecto de la presencia de diferentes proporciones de RPCC provenientes de una central termoeléctrica, sobre el módulo resiliente (M r ) de un suelo fino (SF) tipo arcilla de baja plasticidad, sin la adición de cementantes o estabilizantes adicionales. Previa caracterización física, química y mineralógica de los materiales, se obtuvo el módulo resiliente para SF y RPCC y para mezclas en peso entre 10% y 40% de RPCC. Con estos resultados, se comparó el comportamiento físico y mecánico de los materiales, específicamente la variación de propiedades índice, clasificación USCS, densidad máxima seca y degradación del módulo resiliente. Este estudio resalta la fuerte dependencia del módulo resiliente con respecto al contenido de agua del suelo debido al carácter parcialmente saturado inherente a los materiales.Palabras clave: Subrasante, arcilla, ceniza volante, residuos producto de combustión del carbón (rpcc), módulo resiliente
En este trabajo se estudia la producción de gas de síntesis (CO+H2) mediante reformado seco de biogás (RSM) utilizando un catalizador Ni/Ce-Al2O3. Los experimentos realizados ayudaron a determinar las condiciones necesarias de operación de la planta experimental para que el proceso sea controlado por la cinética de reacción.
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