Kenton Atwood

Bio: Kenton Atwood is an academic researcher. The author has contributed to research in topics: Catalysis & Iron oxide cycle. The author has an hindex of 5, co-authored 6 publications receiving 124 citations.

A review of dry (CO2) reforming of methane over noble metal catalysts

Abstract: Dry (CO2) reforming of methane (DRM) is a well-studied reaction that is of both scientific and industrial importance. This reaction produces syngas that can be used to produce a wide range of products, such as higher alkanes and oxygenates by means of Fischer–Tropsch synthesis. DRM is inevitably accompanied by deactivation due to carbon deposition. DRM is also a highly endothermic reaction and requires operating temperatures of 800–1000 °C to attain high equilibrium conversion of CH4 and CO2 to H2 and CO and to minimize the thermodynamic driving force for carbon deposition. The most widely used catalysts for DRM are based on Ni. However, many of these catalysts undergo severe deactivation due to carbon deposition. Noble metals have also been studied and are typically found to be much more resistant to carbon deposition than Ni catalysts, but are generally uneconomical. Noble metals can also be used to promote the Ni catalysts in order to increase their resistance to deactivation. In order to design catalysts that minimize deactivation, it is necessary to understand the elementary steps involved in the activation and conversion of CH4 and CO2. This review will cover DRM literature for catalysts based on Rh, Ru, Pt, and Pd metals. This includes the effect of these noble metals on the kinetics, mechanism and deactivation of these catalysts.

CO2 Reforming of CH4

Abstract: Although technological practice should minimize environmental impact, this is not always economically feasible. During the past decade, for example, there has been increasing global concern over th...

The Water-Gas Shift Reaction

Abstract: The water-gas shift is a reversible, exothermic chemical reaction, usually assisted by a catalyst, and is the' reaction of steam with carbon monoxide to produce carbon dioxide and hydrogen gas

Partial oxidation of methane to synthesis gas using carbon dioxide

Abstract: INCREASING concern about world dependence on petroleum oil has generated interest in the more efficient use of natural gas1–4. The conversion of methane to the common feedstock synthesis gas (carbon monoxide and hydrogen) by steam reforming is already well established5, and we have shown recently that yields of syn-thesis gas in excess of 90% can be obtained at moderate tem-peratures and ambient pressure by partial oxidation, with air or oxygen, over supported transition-metal catalysts6,7. The use of carbon dioxide as an oxidant for conversion of natural gas to synthesis gas is well established in steam reforming5, and is also known in CO2 reforming (for example, the Calcor process8,9), in which the use of excess CO2 yields mainly CO. In the present work, we describe an alternative catalytic strategy for CO2 reform-ing which gives excellent yields (90%) from a stoichiometric (1:1) feed of CO2 and CH4. Carbon deposition ('coking'), which is a hazard of CO2-reforming routes, is suppressed here by the use of catalysts based on platinum-group metals. We show that the exothermic partial oxidation of CH2 and the endothermic CO2-reforming reaction can be carried out simultaneously, thus introducing the possibility of tuning the thermodynamics of the process.

Carbon Dioxide Reforming of Methane To Produce Synthesis Gas over Metal-Supported Catalysts: State of the Art

Abstract: Carbon dioxide reforming of methane produces synthesis gas with a low hydrogen to carbon monoxide ratio, which is desirable for many industrial synthesis processes. This reaction also has very important environmental implications since both methane and carbon dioxide contribute to the greenhouse effect. Converting these gases into a valuable feedstock may significantly reduce the atmospheric emissions of CO2 and CH4. In this paper, we present a comprehensive review on the thermodynamics, catalyst selection and activity, reaction mechanism, and kinetics of this important reaction. Recently, research has centered on the development of catalysts and the feasible applications of this reaction in industry. Group VIII metals supported on oxides are found to be effective for this reason. However, carbon deposition causing catalyst deactivation is the major problem inhibiting the industrial application of the CO2/CH4 reaction. Ni-based catalysts impregnated on certain supports show carbon-free operation and thus attract much attention. To develop an effective catalyst for CO2 reforming of CH4 and accelerate the commercial application of the reaction, the following are identified to be the most important areas for future work: (1) selection of metal and support and studying the effect of their interaction on catalyst activity; (2) the effect of different promoter on catalyst activity; (3) the reaction mechanism and kinetics; and (4) pilot reactor performance and scale-up operation.