Catalytic deactivation of methane steam reforming catalysts. 1. Activation

CeO2-promoted Ni/Al2O3 catalysts were fabricated by impregnation. The effects of the CeO2 promotion and impregnation order on the microstructural evolution and catalytic durability were investigated for methane steam reforming. The CeO2-promoter nanoparticles resulted in good dispersion and reduced particle size of Ni catalysts. The enhanced durability of CeO2-promoted Ni/Al2O3 catalysts might be associated with the depression of carbon deposition by the presence of CeO2-promoter nanoparticles.

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In silicosearch for novel methane steam reforming catalysts

New Journal of Physics ◽

10.1088/1367-2630/15/12/125021 ◽

2013 ◽

Vol 15 (12) ◽

pp. 125021 ◽

Cited By ~ 41

Author(s):

Yue Xu ◽

Adam C Lausche ◽

Shengguang Wang ◽

Tuhin S Khan ◽

Frank Abild-Pedersen ◽

...

Keyword(s):

Steam Reforming ◽

Methane Steam Reforming ◽

Methane Steam ◽

Reforming Catalysts ◽

Steam Reforming Catalysts

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A Study on CO2 Methanation and Steam Methane Reforming over Commercial Ni/Calcium Aluminate Catalysts

Energies ◽

10.3390/en13112792 ◽

2020 ◽

Vol 13 (11) ◽

pp. 2792 ◽

Cited By ~ 3

Author(s):

Gabriella Garbarino ◽

Federico Pugliese ◽

Tullio Cavattoni ◽

Guido Busca ◽

Paola Costamagna

Keyword(s):

Steam Reforming ◽

Operating Conditions ◽

Packed Bed Reactor ◽

Methane Steam Reforming ◽

Hydrogen Yield ◽

Reactor Model ◽

Co2 Methanation ◽

Methane Steam ◽

Reforming Catalysts ◽

Steam Reforming Catalysts

Three Ni-based natural gas steam reforming catalysts, i.e., commercial JM25-4Q and JM57-4Q, and a laboratory-made catalyst (26% Ni on a 5% SiO2–95% Al2O3), are tested in a laboratory reactor, under carbon dioxide methanation and methane steam reforming operating conditions. The laboratory catalyst is more active in both CO2 methanation (equilibrium is reached at 623 K with 100% selectivity) and methane steam reforming (92% hydrogen yield at 890 K) than the two commercial catalysts, likely due to its higher nickel loading. In any case, commercial steam reforming catalysts also show interesting activity in CO2 methanation, reduced by K-doping. The interpretation of the experimental results is supported by a one-dimensional (1D) pseudo-homogeneous packed-bed reactor model, embedding the Xu and Froment local kinetics, with appropriate kinetic parameters for each catalyst. In particular, the H2O adsorption coefficient adopted for the commercial catalysts is about two orders of magnitude higher than for the laboratory-made catalyst, and this is in line with the expectations, considering that the commercial catalysts have Ca and K added, which may promote water adsorption.

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Catalytic properties of Atomized Ni3Al Powder for Methane Steam Reforming

10.1557/proc-1128-u06-09 ◽

2008 ◽

Author(s):

Toshiyuki Hirano ◽

Yan Ma ◽

Ya Xu ◽

Masahiko Demura

Keyword(s):

Steam Reforming ◽

Catalytic Properties ◽

Methane Steam Reforming ◽

Methane Steam ◽

Al Powder

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Ultra-Low Amounts of Palladium (0.005-0.05 Wt% Pd) Supported on Titania: Remarkable Low-Temperature Activity for NO Reduction with CO and Structure-Function Property Relationships in Methane Oxidation

10.26434/chemrxiv.13489380.v1 ◽

2020 ◽

Author(s):

Konstantin Khivantsev ◽

Libor Kovarik ◽

Nicholas R. Jaegers ◽

János Szanyi ◽

Yong Wang

Keyword(s):

Nitric Oxide ◽

Carbon Monoxide ◽

Methane Oxidation ◽

Steam Reforming ◽

Methane Steam Reforming ◽

Oxide Reduction ◽

Water Steam ◽

Methane Steam ◽

Anatase Titania ◽

Nitric Oxide Reduction

Atomically dispersed Pd +2 cations with ultra-dilute loading of palladium (0.005-0.05 wt%) were anchored on anatase titania and characterized with FTIR, microscopy and catalytic tests. CO infrared adsorption produces a sharp, narrow mono-carbonyl Pd(II)-CO band at ~2,130 cm-1 indicating formation of highly uniform and stable Pd+2 ions on anatase titania. The 0.05 wt% Pd/TiO2 sample was evaluated for methane combustion under dry and wet (industrially relevant) conditions in the presence and absence of carbon monoxide. Notably, we find the isolated palladium atoms respond dynamically upon oxygen concentration modulation (switching-on and switching off). When oxygen is removed from the wet methane stream, palladium ions are reduced to metallic state by methane and catalyze methane steam reforming instead of complete methane oxidation. Re-admission of oxygen restores Pd+2 cations and switches off methane steam reforming activity. Moreover, 0.05 wt% Pd/TiO2 is a competent CO oxidation catalyst in the presence of water steam with 90% CO conversion and TOF ~ 4,000 hr-1 at 260 ⁰C. More importantly, we find that diluting 0.05 wt% Pd/titania sample with titania to ultra-low 0.005 wt% palladium loading produces a remarkably active material for nitric oxide reduction with carbon monoxide under industrially relevant conditions with >90% conversion of nitric oxide at 180 ⁰C (~460 ppm NO and 150 L/g*hr flow rate in the presence of >2% water steam) and TOF ~6,000 hr-1. Pd thus outperforms state-of-the-art rhodium containing catalysts with (15-20 times higher rhodium loading; rhodium is ~ 3 times more expensive than palladium). Furthermore, palladium catalysts are more selective towards nitrogen and produce significantly less ammonia relative to the more traditional rhodium catalysts due to lower Pd amount nd lower water-gas-shift activity. Our study is the first example of utilizing ultra-low (0.05 wt% and less) noble metal (Pd) amounts to produce heterogeneous catalysts with extraordinary activity for nitric oxide reduction. This opens up a pathway to study other Pd, Pt and Rh containing materials with ultra-low loadings of expensive noble metals dispersed on titania or titania-coated oxides for industrially relevant nitric oxide abatement.

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