MoOx-promoted Pt catalysts for the water gas shift reaction at low temperatures

Xu, Xuejun; Fu, Qiang; Bao, Xinhe

doi:10.1016/s1872-2067(14)60294-1

Cited by 5 publications

(3 citation statements)

References 41 publications

(34 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The catalytic performance was found to be influenced by the ability of the support matrices to disperse the copper nanoparticles. The results showed that the silica aerogel was a highly stable matrix throughout the catalytic cycles with a constant CO conversion [133].…”

Section: Type Of Metal Oxide Supportmentioning

confidence: 95%

“…11b) [132]. Marras et al used two different types of porous silica, namely aerogel and cubic mesostructured, as supports for Cu-based nanoparticles that were tested for WGS reaction at 200-350°C [133]. The catalytic performance was found to be influenced by the ability of the support matrices to disperse the copper nanoparticles.…”

Section: Type Of Metal Oxide Supportmentioning

confidence: 99%

See 1 more Smart Citation

A review of recent advances in water-gas shift catalysis for hydrogen production

2020

View full text Add to dashboard Cite

The water-gas shift reaction (WGSR) is an intermediate reaction in hydrocarbon reforming processes, considered one of the most important reactions for hydrogen production. Here, water and carbon monoxide molecules react to generate hydrogen and carbon dioxide. From the thermodynamics aspect, pressure does not have an impact, whereas low-temperature conditions are suitable for high hydrogen selectivity because of the exothermic nature of the WGSR reaction. The performance of this reaction can be greatly enhanced in the presence of suitable catalysts. The WGSR has been widely studied due do the industrial significance resulting in a good volume of open literature on reactor design and catalyst development. A number of review articles are also available on the fundamental aspects of the reaction, including thermodynamic analysis, reaction condition optimization, catalyst design, and deactivation studies. Over the past few decades, there has been an exceptional development of the catalyst characterization techniques such as near-ambient x-ray photoelectron spectroscopy (NA-XPS) and in situ transmission electron microscopy (in situ TEM), providing atomic level information in presence of gases at elevated temperatures. These tools have been crucial in providing nanoscale structural details and the dynamic changes during reaction conditions, which were not available before. The present review is an attempt to gather the recent progress, particularly in the past decade, on the catalysts for lowtemperature WGSR and their structural properties, leading to new insights that can be used in the future for effective catalyst design. For the ease of reading, the article is divided into subsections based on metals (noble and transition metal), oxide supports, and carbon-based supports. It also aims at providing a brief overview of the reaction conditions by including a table of catalysts with synthesis methods, reaction conditions, and key observations for a quick reference. Based on our study of literature on noble metal catalysts, atomic Pt substituted Mn 3 O 4 shows almost full CO conversion at 260°C itself with zero methane formation. In the case of transition metals group, the inclusion of Cu in catalytic system seems to influence the CO conversion significantly, and in some cases, with CO conversion improvement by 65% at 280°C. Moreover, mesoporous ceria as a catalyst support shows great potential with reports of full CO conversion at a low temperature of 175°C.

show abstract

Section: Type Of Metal Oxide Supportmentioning

confidence: 95%

Section: Type Of Metal Oxide Supportmentioning

confidence: 99%

A review of recent advances in water-gas shift catalysis for hydrogen production

2020

View full text Add to dashboard Cite

show abstract

“…The authors found that the active sites for WGS reaction lied on the interface between MoO x patches and the Pt particles and that the loading of 1.7% (Mo/Pt atomic ratio 1 4 ) assured the optimal coverage of molybdenum oxides on platinum. In such conditions, a bifunctional reaction mechanism was identified: water can be activated on the interfacial sites and react with the carbon monoxide adsorbed on the nearby Pt nanoparticles [90].…”

Section: Mo-promoted Catalystsmentioning

confidence: 99%

Platinum Based Catalysts in the Water Gas Shift Reaction: Recent Advances

Palma

Ruocco

Cortese

et al. 2020

Metals

View full text Add to dashboard Cite

The water gas shift (WGS) is an equilibrium exothermic reaction, whose corresponding industrial process is normally carried out in two adiabatic stages, to overcome the thermodynamic and kinetic limitations. The high temperature stage makes use of iron/chromium-based catalysts, while the low temperature stage employs copper/zinc-based catalysts. Nevertheless, both these systems have several problems, mainly dealing with safety issues and process efficiency. Accordingly, in the last decade abundant researches have been focused on the study of alternative catalytic systems. The best performances have been obtained with noble metal-based catalysts, among which, platinum-based formulations showed a good compromise between performance and ease of preparation. These catalytic systems are extremely attractive, as they have numerous advantages, including the feasibility of intermediate temperature (250–400 °C) applications, the absence of pyrophoricity, and the high activity even at low loadings. The particle size plays a crucial role in determining their catalytic activity, enhancing the performance of the nanometric catalytic systems: the best activity and stability was reported for particle sizes < 1.7 nm. Moreover the optimal Pt loading seems to be located near 1 wt%, as well as the optimal Pt coverage was identified in 0.25 ML. Kinetics and mechanisms studies highlighted the low energy activation of Pt/Mo2C-based catalytic systems (Ea of 38 kJ·mol−1), the associative mechanism is the most encountered on the investigated studies. This review focuses on a selection of recent published articles, related to the preparation and use of unstructured platinum-based catalysts in water gas shift reaction, and is organized in five main sections: comparative studies, kinetics, reaction mechanisms, sour WGS and electrochemical promotion. Each section is divided in paragraphs, at the end of the section a summary and a summary table are provided.

show abstract