Ask Lysne, Ida Saxrud, Rémi L.G. Snidaro, Edd A. Blekkan
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引用次数: 0
Abstract
Steam reforming is a promising approach to remove biomass gasification tar impurities. Noble metal promotion (Pt/Pd/Rh), Ni+Co loading (20–40 wt%) and calcination temperature (600–800 °C) effects were investigated with hydrotalcite-derived Ni-Co/Mg(Al)O catalysts for bio-syngas tar steam reforming. Fresh catalysts were characterized by XRD, ICP-MS, XRF, N2-physisorption, H2-chemisorption and TPR. Small-diameter metal particles were achieved (5.1–5.8 nm) below a Ni+Co loading threshold (above 30 wt%). Model bio-syngas activity tests were performed (CH4/H2/CO/CO2 molar ratio = 10/35/25/25, 700 °C, steam-to-carbon = 3.0) with and without tar addition (toluene/1-methylenaphthalene, 10 g/Nm3). Tar elimination was achieved with all samples. Enhanced reforming activity accompanied by strong tar active site inhibition effects were found for the Rh promoted catalyst. Noble metal promoted samples were effectively reduced in the bio-syngas environment (H2/CO/CH4) without any pre-reduction (in situ activation by the action of the syngas) with Rh > Pt > Pd. Coke characterization was conducted with TPO-MS and Raman spectroscopy. High-dispersion 20NiCo/30NiCo samples were strongly deactivated through active site inhibition and coke formation. High-temperature calcination (800 °C) reduced the deactivation effects of the coke deposition, attributed to enhanced Mg(Al)O-assisted coke gasification.
期刊介绍:
The Journal of Catalysis publishes scholarly articles on both heterogeneous and homogeneous catalysis, covering a wide range of chemical transformations. These include various types of catalysis, such as those mediated by photons, plasmons, and electrons. The focus of the studies is to understand the relationship between catalytic function and the underlying chemical properties of surfaces and metal complexes.
The articles in the journal offer innovative concepts and explore the synthesis and kinetics of inorganic solids and homogeneous complexes. Furthermore, they discuss spectroscopic techniques for characterizing catalysts, investigate the interaction of probes and reacting species with catalysts, and employ theoretical methods.
The research presented in the journal should have direct relevance to the field of catalytic processes, addressing either fundamental aspects or applications of catalysis.