Coupling of methane

Rare-earth oxides (La2C 3, Dy203) have been shown to be active in isosynthesis.283 284 It was also observed that zirconia may catalyze the highly selective formation of isobutylene under appropriate conditions.285 Two chain growth processes, CO insertion into aldehydic Zr-C bonds and condensation between methoxide and 

Isoalkanes can also be synthesized by using two-component catalyst systems composed of a Fischer-Tropsch catalyst and an acidic catalyst. Ruthenium-exchanged alkali zeolites288 289 and a hybrid catalyst290 (a mixture of RuNaY zeolite and sulfated zirconia) allow enhanced isoalkane production. On the latter catalyst 91% isobutane in the C4 fraction and 83% isopentane in the C5 fraction were produced. The shift of selectivity toward the formation of isoalkanes is attributed to the secondary, acid-catalyzed transformations on the acidic catalyst component of primary olefinic (Fischer-Tropsch) products. 

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The direct methane conversion technology, which has received the most research attention, involves the oxidative coupling of methane to produce higher hydrocarbons (qv) such as ethylene (qv). These olefinic products may be upgraded to Hquid fuels via catalytic oligomerization processes. 

Generally, the most developed processes involve oxidative coupling of methane to higher hydrocarbons. Oxidative coupling converts methane to ethane and ethylene by... 

Although ethylene is produced by various methods as follows, only a few are commercially proven thermal cracking of hydrocarbons, catalytic pyrolysis, membrane dehydrogenation of ethane, oxydehydrogenation of ethane, oxidative coupling of methane, methanol to ethylene, dehydration of ethanol, ethylene from coal, disproportionation of propylene, and ethylene as a by-product. 

S. Seimanides, P. Tsiakaras, X.E. Verykios, and C.G. Vayenas, Oxidative Coupling of Methane over Yttria-doped Zirconia Solid Electrolyte, Appl. Catal. 68, 41-53 (1991). 

P.H. Chiang, D. Eng, and M. Stoukides, Solid electrolyte aided direct coupling of methane,/. Catal. 139,683-687(1993). 

Oxidative Coupling of Methane to Ethylene with 85% Yield in a Gas Recycle Electrocatalytic or Catalytic Reactor-Separator... 

Keller and Bhasin were first to report in 1982 [1] on the catalytic one-step oxidative dimerization or coupling of methane (OCM) to C2 hydrocarbons, ethane and ethylene. Numerous investigations have followed this seminal work and a large number of catalysts have been found which give total selectivity to C2 hydrocarbons higher than 90% at low (<2%) methane conversion [2-6]. 

Two conqiletely different behaviors of oxidative transformation of methane, namely the Oxidative Coupling of Methane to C2 Hydrocarbons(OCM) and the Partial Oxidation of Methane to Syngas(POM), were performed and related over the nickel-based catalysts due to different modification and different supports. It is concluded that the acidic property favors keeping the reduced nickel and the reduced nickel is necessary for POM reaction, and the bade property frvors keeping the oxidized nickel and the oxidized mckel is necessary for OCM reaction. POM and OCM reactions proceed at different active sites caused by different... 

Thompson, W. J., Microreactor system for hydrogen generation and oxidative coupling of methane, in Proceedings of the 4th International Conference on Microreaction Technology, IMRET 4, pp. 351-357 (5-9 March 2000), AIChE Topical Conf Proc., Atlanta, USA. 

Oxidative coupling of methane to yield C2 and higher hydrocarbons... 

The oxidative coupling of methane has been studied by several authors. The most elusive transformation has been the oxidative coupling of methane into C2 hydrocarbons (ethene, ethane), because the reaction is more endothermic than other transformations [2]. The application of fast and efficient microwave heating to endothermic reactions is particular interest. 

Oxidative coupling of methane has also been examined by other authors [2, 68-70], who have used different catalysts. 

Oxidative coupling of methane to yield C2 and higher hydrocarbons 358 Direct partial oxidation of methane to produce methanol and other oxygenates 360... 

IFP Oxypyrolysis Also called NGOP. A process for converting natural gas to gasoline, based on the oxidative coupling of methane to ethane in a fixed-bed reactor. Developed in 1991 by the Institut Frangais du Petrole. 

In the 1980s, the oxidative coupling of methane to give ethylene and ethane was reported by Keller and Bhasin (8), whose discovery prompted numerous attempts to convert methane directly—and not only to ethylene and ethane (8), but also to methanol and formaldehyde (9) (Table I). Research on oxidative coupling of methane was motivated by results showing that the methane was... 

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