Coupling of methane and

Besides oxidative coupling of methane and double bond isomerization reactions (242), a limited number of organic transformations have been carried out with alkali-doped alkaline earth metal oxides, including the gas-phase condensation of acetone on MgO promoted with alkali (Li, Na, K, or Cs) or alkaline earth (Ca, Sr, or Ba) (14,120). The basic properties of the samples were characterized by chemisorption of CO2 (Table VI). 

Unfortunately, these requirements have not yet fully been met for any catalytic reaction, although for some simple catalytic reactions reasonable approaches are known. Such reactions are the oxidation of CO over a supported Rh catalyst [46,47], ammonia synthesis over iron [48, 49], and the HCN synthesis over a Pt gauze catalyst. More recently Wolf [50] carried out a micro-kinetic analysis of the primary reaction steps in the oxidative coupling of methane and also related the rate... 

The question how immediately arises with respect to this success as it is obvious that the pathway (l)-(4) eventually leads to the same net result as the direct (uphill in terms of free energy) coupling of methane and carbon dioxide. First of all, this detour works because mechanisms exist for these sequential steps that permit the reactions to be carried out. Why, though, does the sled ultimately ascend the hill What kind of force is responsible for driving the sled uphill ... 

Another reaction to be mentioned briefly is the Ta+-mediated coupling of methane and carbon dioxide to afford ketene the latter can serve as a precursor for acetic acid (Wesendrup and Schwarz 1995a,b). The rather attractive, yet hypothetical, coupling Reaction (7.11) is endothermic, however. In the mass spectrometric model study, the thermochemical driving force is provided by the oxidation of tantalum yielding the TaC>2 cation as the final product (Sandig and Koch 1998). Therefore, the coupled activation of methane and carbon dioxide so far remains stoichiometric ... 

Examples Oxidative coupling of methane (OCM), oxidative dehydrogenation of C -C4 alkanes, partial oxidation of methane to synthesis gasa, combined oxidative coupling of methane and toluene to styrene Surface-stabilized combustion, partial oxidation of methane to synthesis gasa, synthesis of cyanic acid from methane, ammonia, and oxygen3... 

COUPLING OF METHANE AND ETHYLENE OVER SULPHATE-TREATED ZIRCONIA... 

The CMR concept involving the forced flow of the reactant stream through the membrane, was also applied by Binkerd et al. [2.373] for the oxidative coupling of methane, and by Lange et al. [2.374] and Lambert and Gonzalez [2.375] for selective hydrogena-... 

Methane can also be co-condensed with some compounds in the presence of heterogeneous catalysts and molecular oxygen (Khcheyan s reaction [80]). Thus, oxidative coupling of methane and acetonitrile gives propionitrile and acrylonitrile ... 

Very interesting alkane functionalizations in the presence of metal ions in the gas phase have also been reported. Schwarz et al. have described recently [11a] a gas-phase model for the platinum-catalyzed coupling of methane and ammonia. Endothermic by 61 kcal mol" reaction... 

Bare Ta cations induce the coupling of methane and carbon dioxide in the gas phase [70a] according to the sequence ... 

Finally, Reaction 22, observed by Burnier et al. [57], is of interest as it represents the reversal of a Fe -mediated coupling of methane and formaldehyde to dimethyl ether, according to Reaction 23. 

Ghareghashi, A., Ghader, S., and Hashemipour, H. (2013) Theoretical analysis of oxidative coupling of methane and Fischer Tropsch synthesis in two consecutive reactors comparison of fixed bed and membrane reactor. /. Ind. Eng. Chem., 19,1811-1826. 

Tables 27.2 (for hydrogen production), 213 (for the oxidative coupling of methane) and 27.4 (for the oxidative dehydrogenation of alkanes).

Figure 31. ARCO process scheme for the production of high-octane gasoline from natural gas by oxidative coupling of methane and subsequent olefin oligomerization [60].

Figure 6. MAS NMR spectra of a sample heated to 300°C for 35 mins and recorded with proton decoupling only (a) aliphatic region (b) aromatic and CO region [29]. Intensities in (a) and (b) are not on the same scale. The inset shows J-coupling of methane and cyclopropane carbons (recorded without decoupling). Spectral assignments are as follows [peak numbers and intensities (s = strong, m = medium, w = weak) are in brackets, for aliphatic and () for aromatic] i-butane 3,s) propane 7,s n-butane 3,9,m n-hexane l,4,8,m i-pentane 1,2,4,10,m) n-heptane l,2,4,8,m methane 13,mj ethane ll,wj cyclopropane 12,w) o-xylene (4,12,17,s) 5 p-xylene (7,13,s) 6) m-xylene (2,12,15,17,w) 5) toluene (2,13,14,1 8, w) 5 1,2,4-tri methyl benzene (4,6,8,1 l,13,16,m) 5,6) ...

Wang, L. Yi, X. Weng, W. et al. Oxidative Coupling of Methane and Oxidative Dehydrogenation of Ethane over La20s Nano-eatalyst at Low temperature. Petrochem. Technol 2007, 36(5), 437-440. 

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