In:
ChemCatChem, Wiley, Vol. 9, No. 12 ( 2017-06-22), p. 2297-2307
Abstract:
Multi‐hollow silicalite‐1 single crystals (MH) were prepared for the first time by an original synthesis pathway by using tetrabutylphosphonium hydroxide (TBPOH) as a mild desilicating agent. This new generation of hierarchical zeolite allowed the encapsulation of nanoparticles (NPs) featuring an enhanced confinement of the metallic guest and a thin wall thickness. The MH catalyst exhibited a better stability for methane steam reforming at 700 °C than a single‐hollow counterpart (SH). Ni average particle size could be kept lower than 4 nm after 20 h on stream for the MH sample. However, a detailed analysis of kinetic data of the structure‐insensitive CO methanation used as a model reaction revealed that the sample activity was adversely affected by two main factors deriving from the preparation steps. First, a siliceous over‐layer derived from the decomposition of intermediate Ni phyllosilicates, which partly covered the resulting Ni nanoparticles. Second, phosphorus from the templates remained in the samples, probably forming a Ni–P compound upon reduction. The overall catalytic activities observed here were therefore a complex interplay of improved dispersion and poisonous effects.
Type of Medium:
Online Resource
ISSN:
1867-3880
,
1867-3899
DOI:
10.1002/cctc.201700233
Language:
English
Publisher:
Wiley
Publication Date:
2017
detail.hit.zdb_id:
2501161-3
Bookmarklink