A structured catalyst with high dispersity of Au species based on hollow SiC foam with porous walls for acetylene hydrochlorination

The catalytic oxidation of silanes to produce silanols using water as an oxidant at mild temperatures is a major challenge in Si-H activation. Highly efficient and easy-to-recycle catalysts based on Pd nanoparticles are in high demand. In this study, Pd nanoparticles embedded in an MgO porous overlayer on an Mg plate as a structured catalyst was prepared by the plasma electrolyte oxidation (PEO) technique. The Pd/MgO catalyst is strongly anchored to the MgO plate, building a structured catalyst. Fabrication parameters such as the temperature of the electrolyte and applied voltage significantly influenced the structure of the obtained Pd/MgO catalyst and in turn its catalytic activity. The catalytic activities of Pd/MgO were evaluated by activation of a Si-H bond for catalyzing the aqueous oxidation of silanes to silanol at mild temperatures. The catalytic activity of Pd nanoparticles is favored by their electro-deficient state due to influence from the MgO substrate. The Pd/MgO catalyst exhibits good performance stability during recycling. This work paves the way for fabricating structured catalysts with long-term stability and enhanced metal–oxide interaction.

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Study of Cu-Zn and Au/TiO2 Catalysts on Anodized Aluminum Monoliths for Hydrogen Generation and Purification

International Journal of Chemical Reactor Engineering ◽

10.1515/ijcre-2015-0119 ◽

2016 ◽

Vol 14 (4) ◽

pp. 831-842 ◽

Cited By ~ 1

Author(s):

E. Adrover ◽

D. Boldrini ◽

N.J. Divins ◽

A. Casanovas ◽

G. Tonetto ◽

...

Keyword(s):

Hydrogen Generation ◽

Methanol Conversion ◽

Incipient Wetness Impregnation ◽

Anodized Aluminum ◽

Homogeneous Surface ◽

Preferential Oxidation Of Co ◽

Structured Catalysts ◽

Structured Catalyst ◽

Catalytic Coating ◽

Catalytic Material

Abstract This work reports the preparation of Cu-Zn and Au/TiO2 catalysts on anodized aluminum monoliths (AAM). The structured catalysts were studied for the generation of H2 by methanol steam reforming (MSR) and its purification by preferential oxidation of CO (CO-PrOx). Initially, it was possible to generate a surface with whiskers and larger surface area by hydrothermal treatment of the AAM. Subsequently, the structured catalysts were synthesized by incipient wetness impregnation (IWI) and hydrothermal synthesis (HS). IWI synthesis allowed for the deposition of a larger amount of catalytic material than HS, with very good adhesion. The TiO2-IWI structured catalyst presented a homogeneous catalytic coating, with the presence of agglomerated particles. On the other hand, Cu-Zn-IWI showed good dispersion of the deposited particles with a homogeneous surface coating. EDX analysis corroborated the presence of Ti, Cu and Zn in all the catalytic surfaces. The incorporation of Au over TiO2-IWI structured catalysts was successfully performed by IWI using a colloidal solution of gold nanoparticles. MSR was studied over the developed metallic monoliths functionalized with Cu-Zn by the IWI method. The samples showed promising results in terms of activity, selectivity, and stability. Both diluted and concentrated methanol + water feeds were assayed. Complete methanol conversion was achieved for the diluted feed. Maximum methanol conversions of 55 % with 60 % H2 yield were measured when the concentrated feed was selected. Promising results were also achieved for the Au-based structured catalysts in the CO-PrOx in an H2-rich atmosphere. Although CO conversions of approximately 60 % were achieved, operating with higher catalyst loadings would be recommended to reach the high CO conversions required for PrOx catalysts.

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Nickel-Based Structured Catalysts for Indirect Internal Reforming of Methane

Applied Sciences ◽

10.3390/app10093083 ◽

2020 ◽

Vol 10 (9) ◽

pp. 3083

Author(s):

Mariarita Santoro ◽

Igor Luisetto ◽

Simonetta Tuti ◽

Silvia Licoccia ◽

Claudia Romano ◽

...

Keyword(s):

Focused Ion Beam ◽

Ion Beam ◽

Operating Conditions ◽

Dry Reforming Of Methane ◽

Metallic Foam ◽

X Ray ◽

Structured Catalysts ◽

Internal Reforming ◽

Structured Catalyst ◽

Coating Method

A structured catalyst for the dry reforming of methane (DRM) was investigated as a biogas pre-reformer for indirect internal reforming solid oxide fuel cell (IIR-SOFC). For this purpose, a NiCrAl open-cell foam was chosen as support and Ni-based samarium doped ceria (Ni-SmDC) as catalyst. Ni-SmDC powder is a highly performing catalyst showing a remarkable carbon resistance due to the presence of oxygen vacancies that promote coke gasification by CO2 activation. Ni-SmDC powder was deposited on the metallic support by wash-coating method. The metallic foam, the powder, and the structured catalyst were characterized by several techniques such as: N2 adsorption-desorption technique, X-ray diffraction (XRD), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX), focused ion beam (FIB), temperature programmed reduction (H2-TPR), and Raman spectroscopy. Catalytic tests were performed on structured catalysts to evaluate activity, selectivity, and stability at SOFC operating conditions.

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Honeycomb Structured Catalysts for H2 Production via H2S Oxidative Decomposition

Catalysts ◽

10.3390/catal8110488 ◽

2018 ◽

Vol 8 (11) ◽

pp. 488 ◽

Cited By ~ 3

Author(s):

Vincenzo Palma ◽

Daniela Barba ◽

Vincenzo Vaiano ◽

Michele Colozzi ◽

Emma Palo ◽

...

Keyword(s):

Catalytic Performance ◽

Dip Coating ◽

H2 Production ◽

Sem Analysis ◽

Operating Conditions ◽

Structured Catalysts ◽

Structured Catalyst ◽

Honeycomb Monolith ◽

Different Temperatures ◽

H2 Yield

Cordierite honeycomb structured catalysts were studied for the reaction of H2S decomposition in the presence of oxygen to obtain H2 and sulphur. An Al2O3-based washcoat was deposited on the honeycomb monolith by a dip-coating procedure. In particular, three different washcoat percentages (15, 20 and 30 wt%) were deposited on the structured carrier and the obtained samples were characterized by N2 adsorption and SEM analysis. The evaluation of the catalytic performance of the three samples was carried out at two different temperatures (1000 °C and 1100 °C). The sample with 30 wt% washcoat content showed the lowest SO2 selectivity at 1000 °C (<0.4%), whereas the H2S conversion and H2 yield values were very similar to those achieved for the samples at 15 and 20 wt% washcoat loading. Based on these results, additional tests were carried out on the catalyst with 30 wt% Al2O3-based washcoat loading, varying the contact time and the H2S inlet concentration to identify the operating conditions that minimize the SO2 formation, obtaining good H2S conversion and H2 yield. The comparison of the structured catalyst with the powder alumina sample has shown the same catalytic performance, exhibiting lower SO2 selectivity.

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NiCoFe spinel-type oxide nanosheet arrays derived from layered double hydroxides as structured catalysts

RSC Advances ◽

10.1039/c4ra00608a ◽

2014 ◽

Vol 4 (101) ◽

pp. 57804-57809 ◽

Cited By ~ 13

Author(s):

Ge Meng ◽

Qiu Yang ◽

Yixi Wang ◽

Xiaoming Sun ◽

Junfeng Liu

Keyword(s):

Catalytic Activity ◽

Layered Double Hydroxides ◽

Spinel Type ◽

Structured Catalysts ◽

Structured Catalyst ◽

Nanosheet Arrays ◽

Double Hydroxides

NiCoFe spinel-type oxide nanosheet arrays derived from layered double hydroxides (LDH) were used as structured catalyst, which exhibited excellent catalytic activity towards the oxidation of styrene.

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Hierarchically structured catalysts for cascade and selective steam reforming/hydrodeoxygenation reactions

Chemical Communications ◽

10.1039/c5cc07244a ◽

2015 ◽

Vol 51 (93) ◽

pp. 16617-16620 ◽

Cited By ~ 5

Author(s):

Junming Sun ◽

Ayman M. Karim ◽

Xiaohong Shari Li ◽

James Rainbolt ◽

Libor Kovarik ◽

...

Keyword(s):

Lignocellulosic Biomass ◽

Steam Reforming ◽

Active Sites ◽

Size Exclusion ◽

Structured Catalysts ◽

Structured Catalyst

A hierarchically structured catalyst with combined steam reforming and hydrodeoxygenation active sites is reported to efficiently upgrade the pyrolysis vapors of lignocellulosic biomass via size-exclusion.

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