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Short contact time catalytic partial oxidation (CPO) of methane has received increasing attention in industrial applications. Understanding of the catalytic system under high pressure and in the presence of sulfur represents a key challenge of this technology. This paper discusses CPO performance using a Rh−Ce catalyst supported on washcoat alumina foam under industrial relevant operating conditions (pressure up to 160 psig and different sulfur levels up to 16 ppm in methane). A long-term experimental run cycling between sulfur-free and sulfur injection conditions was conducted to examine the influence of sulfur on the catalyst. Sulfur effects were also evaluated under different sulfur levels and with different feed compositions. A dual zone reaction model was used to explain the effects of pressure, sulfur level, and the O/C ratio on CPO catalytic performance. Engineering challenges and requirements of the CPO process for industrial applications were discussed on the basis of recent advances in the understanding of CPO chemistry. [ABSTRACT FROM AUTHOR]

In this study, a network of reactions involved in the ethanol steam reforming (ESR) over supported Co catalysts has been investigated using temperature-programmed reaction (TPRxn) and isotopic labeling techniques. The products and intermediates in the gas phase have been monitored by mass spectrometry (MS) as a function of temperature. Ethanol conversion and product distribution obtained in steady-state reaction experiments have also been presented. The results point to a complex network of reactions that directly impact the selectivity and H2yield that can be obtained in ethanol steam reforming. The reaction network is governed by the temperature range as well as the type of catalyst used, with catalysts exhibiting higher oxygen mobility favoring complete oxidation of ethanol to CO2and leading to increased hydrogen yield as well as improved stability. [ABSTRACT FROM AUTHOR]

Organosilicon compounds can form novel electrolytes having a number of unusual properties, including high electrochemical stability, high thermal stability, and low viscosity. Vertically aligned carbon nanofibers can act as exceptionally good nanostructured electrodes, with the vertical orientation and presence of edge-plane graphite along the sidewalls providing desirable electrochemical properties. We have explored the electrical properties of the interfaces of VACNF electrodes with a model organosilicon electrolyte solution. The compound 1-(3-2-2-(2-methoxy-ethoxy)-ethoxy-ethoxy-propyl)-1,1,3,3,3-pentamethyl-disiloxane (2SM3) with added lithium bis-oxalato-borate (LiBOB) was used. Forests of vertically aligned carbon nanofibers (VACNFs) ∼80 nm in diameter grown by plasma-enhanced chemical vapor deposition (PECVD) were used as electrodes. Our results show that the resulting interfaces yield interfacial capacitances equal to the increase in geometric area, indicating full electrochemical accessibility of the nanofiber sidewalls. Measurements as a function of potential perfect stability at applied voltages up to 3 V. Some initial Faradaic reactions arise near 3.5 V, but these decrease within a few cycles to produce interfaces that exhibit excellent stability up to 5 V while yielding >1000 F/cm2from nanofibers only 2 m long. The results show that the organosilicon electrolyte combined with VACNFs provides excellent electrochemical properties. The results have implications for understanding the ability to integrate organosilicon electrolytes with high-surface-area carbon materials for applications such as electrochemical double-layer capacitors and lithium-ion batteries. [ABSTRACT FROM AUTHOR]