High-Stable Mesoporous Ni-Ce/Clay Catalysts for Syngas Production

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High-Stable Mesoporous Ni-Ce/Clay Catalysts for Syngas Production Carlos Enrique Daza • Oscar A. Gamba • Yesid Herna´ndez Miguel A. Centeno • Fanor Mondrago´n • Sonia Moreno • Rafael Molina



Received: 1 November 2010 / Accepted: 9 March 2011 / Published online: 22 March 2011 Ó Springer Science+Business Media, LLC 2011

Abstract A mesoporous-type catalytic support was synthesized through the modification of a smectite with polyvinyl alcohol (PVA) and microwaves. Texture and micro-morphology of the support was determined. Several techniques were employed in order to describe the chemical environment of active species on the surface. Ni0 particle sizes were dependent on the structural site of reducible species. High stable Ni-Ce catalysts (calcined at 800 °C) were evaluated in the CO2 reforming of methane reaction at 700 °C (WHSV = 96 L g-1 h-1, without dilution gas and pre-reduction). The catalysts have presented CH4 conversions between 40 and 65%, CO2 conversion between 35 and 65% and H2/CO ratios between 0.2 and 0.4. Keywords Delamination  Clay mineral  Syngas  Reforming

C. E. Daza  O. A. Gamba  S. Moreno  R. Molina (&) Estado So´lido y Cata´lisis Ambiental. Departamento de Quı´mica, Facultad de Ciencias, Universidad Nacional de Colombia, AK 30 No. 45-03, Bogota´, Colombia e-mail: [email protected] Y. Herna´ndez  M. A. Centeno Instituto de Ciencia de Materiales de Sevilla, Centro Mixto CSIC-Universidad de Sevilla, Avda. Ame´rico Vespucio 49, 41092 Sevilla, Spain F. Mondrago´n Quı´mica de Recursos Energe´ticos y Medio Ambiente, Universidad de Antioquia, Cra. 53 61-30, Medellı´n, Colombia Present Address: C. E. Daza Departamento de Quı´mica, Pontificia Universidad Javeriana, Cra. 7 No. 43-82, Bogota´, Colombia e-mail: [email protected]

1 Introduction For several decades modified clay minerals have been used as functional materials in catalytic reactions as supports and/ or catalysts, not only for their low cost and high availability but also because of their particular physicochemical properties. The final textural and morphological properties of the material can be modified by choosing and changing different synthesis parameters as the nature of the mineral and the modifying species, the particle size, heat treatment, among others [1–8]. Clay modification allows obtaining nanocomposites with open and rigid structures through the modification of the interlayer space of the structure. Specifically, the microstructural morphology of modified clays is a matter of vital importance in the textural properties of the material. The modification process of clay minerals can be oriented to generate a face to face-type layered ordering as in the case of pillared clays or edge to face or edge to face type aggregates in associations known as delaminated clays [9–11]. The interest in delaminated clays lies in that these materials present meso- and macro-porosity, which extends their catalytic and adsorbent applications with high selectivity of shape for species and molecules of great size. The wide distrib