Behavior of Coprecipitated NiAl2O4/Al2O3 Catalysts for Low-Temperature Methane Steam Reforming
The suitability of the nickel aluminate phase as an effective precursor for producing highly active and stable Ni/alumina catalysts was investigated in the steam reforming of methane with a H2O/CH4 ratio of 3 in the 450–650 °C temperature range. Particularly, the effect of the preparation route, inc...
| Autores: | , , , , , |
|---|---|
| Tipo de recurso: | artículo |
| Fecha de publicación: | 2014 |
| País: | España |
| Institución: | Universidad del País Vasco |
| Repositorio: | Addi. Archivo Digital para la Docencia y la Investigación |
| OAI Identifier: | oai:addi.ehu.eus:10810/71136 |
| Acceso en línea: | http://hdl.handle.net/10810/71136 |
| Access Level: | acceso abierto |
| Palabra clave: | catalyst nickel oxides redox reactions spinel |
| Sumario: | The suitability of the nickel aluminate phase as an effective precursor for producing highly active and stable Ni/alumina catalysts was investigated in the steam reforming of methane with a H2O/CH4 ratio of 3 in the 450–650 °C temperature range. Particularly, the effect of the preparation route, including dissolution followed by crystallization, coimpregnation, and coprecipitation, for obtaining either bulk or alumina-supported samples was analyzed. A special attention was paid to correlating the characteristics of the calcined catalytic precursors with a Ni content varying between 17 and 33 wt %, namely, textural properties, composition, nature, and relative abundance of the existing nickel phases (NiAl2O4 and NiO), as well as reducibility, with the Ni crystallite size, dispersion, and metallic surface area obtained after a severe high-temperature reduction step (850 °C). A high intrinsic activity was found for the coprecipitated catalysts. This route was also effective for increasing the available metallic surface area. The best reforming performance (with a methane conversion of 78–80% and yield of hydrogen close to 1.63 at 650 °C and 38 400 cm3 CH4 g–1 h–1) was achieved by a reduced alumina-supported (17 wt % Ni)NiAl2O4 catalyst and the bulk NiAl2O4 catalysts prepared by coprecipitation. |
|---|