Carbon dioxide reforming of methane

Temperature dependence of thermodynamic equilibrium composition of the products obtained from CH4 C02 = 1 1 (molar) mixture at atmospheric pressure. 

Another important factor affecting carbon deposition is the catalyst surface basicity. In particular, it was demonstrated that carbon formation can be diminished or even suppressed when the metal is supported on a metal oxide carrier with a strong Lewis basicity [47]. This effect can be attributed to the fact that high Lewis basicity of the support enhances the C02 chemisorption on the catalyst surface resulting in the removal of carbon (by surface gasification reactions). According to Rostrup-Nielsen and Hansen [12], the amount of carbon deposited on the metal catalysts decreases in the following order  

The catalysts supports and promoters have a significant effect on the rate of carbon deposition. In particular, Zr02 has been widely used as a support for Pt because of the lower rate of carbon deposition compared to other supports [48]. The authors demonstrated the following order of the carbon formation rate  

This sequence of steps was derived from a series of pulsed adsorption experiments, in which CH4 was decomposed stoichiometrically to carbon and H2, whereas C02 was shown to react stoichiometrically with the surface carbon yielding CO. 

The addition of steam to the CH4/C02 feedstock to avoid excessive carbon formation is a widely used technique in practical systems [3]. The resulting C02-steam gasification of methane process can be described by the following chemical equation  

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Carbon dioxide reforming of methane to produce synthesis gas, i.e, a mixture of carbon monoxide and hydrogen (COj+CH, ZCO ZHj, = 261 0 kJ/mol) has attracted substantial... 

Zhang, Z.L. and Verykios, X.E., Carbon dioxide reforming of methane to synthesis gas over supported Ni catalysts, Catal. Today, 21, 589,1994. 

A.M Gadalla, M.E. Sommer, Carbon dioxide reforming of methane on nickel catalysts, Chemical Engineering Science, 44, 2825, 1989... 

Problem of coke formation on Ni/Zr02 catalysts during the carbon dioxide reforming of methane... 

On the other hand, it is known that catalyst support exerts a great influence on the catalytic properties of the metallic particles deposited on it during the carbon dioxide reforming of methane. So for a given metal, catalytic activities can be changed [5], product selectivities modified [6] and carbon deposition resistivity altered [7]. Also the addition of certain promoters can improve the catalytic behavior of a given supported metal catalyst. In particular we have shown the benefit of the MgO addition to cobalt catalyst [ 8, 9]. 

Wang, S. and Lu, G.Q. Role of Ce02 in Ni/Ce02-Al203 catalysts for carbon dioxide reforming of methane. Applied Catalysis. B, Environmental, 1998, 19 (3-4), 267. 

Rostrup-Nielsen, J.R. and Bak-Hansen, J.H. Carbon dioxide reforming of methane over transition metals. Journal of Catalysis, 1993, 144, 38. 

Richardson, J.T. and Paripatyadar, S.A. Carbon dioxide reforming of methane with supported rhodium. Applied Catalysis, 1990, 61 (1), 293. 

Bodrov et al. (1964) found in the carbon dioxide reforming of methane that for CO2ICH4 1, the reaction rate can be described by equation (3.59) developed for steam reforming of methane. The study concluded that methane does not react with CO2 but that it does react with steam. The steam is produced when hydrogen (formed from the adsorption and dissociation of methane) reacts with CO2 in the water-gas shift reaction ... 

WANG, S., LU, G.Q., Carbon Dioxide Reforming of Methane to Produce Synthesis Gas over Metal-Supported Catalysts State of the Art, Energy Fuels 10 (1996) 896-904. 

Studies on Carbon Deposition of the Nickel-based Catalysts for Carbon Dioxide Reforming of Methane" ... 

The morphology and properties of the carbon deposition of the nickel-based catalysts for carbon dioxide reforming of methane are investigated. Silica supported nickel catalysts were more facile to carbon deposition than alumina supported catalysts. The decomposition of methane resulted in the formation of at least three kinds of surface carbon species on supported nickel catalysts. Carbidic C , carbonaceous Cp and carbidic clusters Cy surface carbon species formed by decomposition of methane showed different thermal stability and reactivity. The carbidic carbon was a very active and important intermediate in the carbon dioxide reforming of methane and the carbidic clusters Cy species might be the precursor of the surface carbon deposition. The partially dehydrogenated Cp species can react with H2 or CO2 to form CH4 or CO. 

Catalytic carbon dioxide reforming of methane (dry reforming methane, DRM) is an excellent alternative route to obtain syngas and has received significant attention in recent years due to its scientific and industrial importance, since it converts two greenhouse gases (methane and carbon dioxide) into valuable synthesis The DRM process is industrially... 

D. Liu et al, MCM-41 supported nickel-based bimetallic catalysts with superior stability during carbon dioxide reforming of methane Effect of strong metal-support interaction,/ Catal, 2009, 266(2), 380-390. 

Cai, W., Ye, L., Zhang, L., Ren, Y., Yue, B., Chen, X., et al. (2014). Highly dispersed nickel-containing mesoporous sihca with superior stability in carbon dioxide reforming of methane the effect of anchoring. Materials, 7(3), 2340—2355. 

Donphai, W., Eaungnawakij, K., Chareonpanich, M., Limtrakul, J. (2014). Effect of Ni-CNTs/mesoceUular silica composite catalysts on carbon dioxide reforming of methane. Applied Catalysis A General, 475, 16—26. 

Li, J., Yoon, H., Wachsman, E. D. (2012). Carbon dioxide reforming of methane in a SrCeo.7Zro.2Euo.1O3a proton conducting membrane reactor. International Journal of Hydrogen Energy, 37(24), 19125-19132. 

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