Methane electrochemical partial oxidation

Electropox [Electrochemical partial oxidation] Also called Pox. An electrochemical process for oxidizing methane to syngas. It combines the partial oxidation and steam reforming of methane with oxygen separation in a single stage. Invented in 1988 by T. J. Mazanec at BP Chemicals. An industrial-academic consortium to develop the process was formed in 1997. 

Zhan, Z., Lin, Y., Pillai, M., Kim, I., Barnett, S. A. (2006). High-rate electrochemical partial oxidation of methane in solid oxide fuel cells. Journal of Power Sources, 161(1), 460—465. Zhang, J., Datta, R. (2002). Sustained potential oscillations in proton exchange membrane fuel cells with PtRu as anode catalyst. Journal of the Electrochemical Society, 149(11), A1423-A1431. 

Zhan Z, Lin Y, Pillai M, Kim I, Barnett SA (2006) High-rate electrochemical partial oxidation of methane in solid oxide fuel cells. J Power Sources 161(l) 460-465... 

The ability to work stably with methane or natural gas fuel allows the application of SOFCs for electrochemical partial oxidation, where both electricity and a chemical product - syngas - are produced [5, 47]. Measured outlet gas constitution matches well with that predicted at equilibrium, due to the good catalytic activity of the Ni anode or an added catalyst. For a SOFC operated at 750 °C with current and methane flow rate set to yield an O /CH4 ratio of 1.2, the methane conversion is nearly 100 % and the... 

Methane oxidation and partial oxidation, electrochemical promotion of, 308 dimerization, 470 reforming, 410 Methanol dehydrogenation electrochemical promotion of, 403 selectivity modification, 404 Methanol oxidation electrochemical promotion of 398 selectivity modification, 400 Microscopy... 

Hamakawa S, Shiozaki R, Hayakawa T, Suzuki K, Murata K, Takehira K, Koizumi M, Nakamura J, and Uchijima T. Partial oxidation of methane to synthesis gas using Ni/Cao.8Sro.2Ti03 anode catalyst. J. Electrochem. Soc. 2000 147 839-844. 

Another partial oxidation reaction that is attracting industrial attention for the application of reactive separations is the production of synthesis gas from methane [Stoukides, 2.127]. The earlier efforts made use of solid oxide solutions as electrolytes. Stoukides and coworkers (Eng and Stoukides [2.200, 2.126], Alqahtany et al. [2.201, 2.202]), for example, using a YSZ membrane in an electrochemical membrane reactor obtained a selectivity to CO and H2 of up to 86 %. They found that a Fe anodic electrode was as active as Ni in producing synthesis gas from methane (Alqahtany et al. [2.201, 2.202]), and that electro-chemically produced O was more effective in producing CO than gaseous oxygen (no ef-... 

Our studies turned from the methane coupling reaction to the investigation of higher temperature methane reactions. Using tubular electrocatalytic cells with Pt anodes, the conversion of methane becomes more selective with CO as the major product at high temperatures. As summarized in Table 6 methane conversions can approach 100% with CO selectivities up to 97% at 1100 C. This suggested that the electrochemical cells could be used for the partial oxidation of methane to synthesis gas. We call this process Electropox, for electrocatalytic partial oxidation. 

Diethehn S., Sfeir J., Clemens F., Van herle J., Favrat D., Planar and tubular perovskite-type membrane reactors for the partial oxidation of methane to syngas , J Solid State Electrochem (8) (2004)611-617. 

Figure 14.16 Scheme of the electrochemical membrane reactor for partial oxidation of methane [119]. 

Notice that due to high operating temperatures, a variety of other processes such as reforming of hydrocarbons, carlxMi oxidation, and water gas shift reaction may also occur at the anode. The inverse electrode reactions occur in the solid oxide electrolysis cells (SOECs) used to cOTivert steam and carbon dioxide into hydrogen and carbon monoxide, respectively. The operation of the electrochemical reactors with SE membranes, which can also be used to cogenerate electricity and valuable chemical products, is typically based on incomplete oxidation or reduction of the reactants as an example, synthesis gas can be produced in SOFCs via the partial oxidation of methane (POM) ... 

For perovskite-based fuel electrodes, Mn-doped lanthanum strontium chromite (Lao.75Sro25Mno.5Cro.5O3, LSCM), developed by Tao and Irvine, has been infiltrated with ceria-based materials by other research groups, who reported that an improved electrocata-lytic activity was achieved when tested with various fuels. " Without infiltration of a ceria phase into LSCM-YSZ anodes, the oxidation of methane was considered to be limited by insufficient oxygen ion conductivity in the lanthanum chromite-based materials. Gd-doped ceria has higher oxide ion conductivity than LSCM, which is also illustrated by an improved performance of these infiltrated electrodes. The mechanism of methane oxidation in Gd-doped ceria-infiltrated LSCM anodes in wet CH4 was considered to involve the partial oxidation of methane by a gas/solid reaction between ceria and methane-generating CO and H2, followed by electrochemical oxidation of the products. The added ceria also suppressed coke formation in these anodes. ... 

In this paper, while taking the conductivity of FeCrAlY supports into account, the electrochemical in situ synthesis/deposition of Ni- and noble-metal-containing HT compounds on a FeCrAlY foam was studied, with the aim of obtaining catalysts for H2 production processes - such as the endothermic steam methane reforming (SMR) [16,17] or the exothermic catalytic partial oxidation (CPO) of methane. The effect of the synthesis parameters on the properties of the film coating and catalytic activity were studied, while paying special attention to the influence of the composition of the HT precursor. 

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