Direct methane conversion

Direct Methane Conversion, Methanol Fuel Cell, and Chemical Recycling of Carbon Dioxide... 

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. 

According to another important and promising technology, hydrocarbons are produced from methanol, which, in turn, is synthesized from synthesis gas. Called the methanol-to-gasoline process, it was practiced on a commercial scale and its practical feasibility was demonstrated. Alternative routes to eliminate the costly step of synthesis gas production may use direct methane conversion through intermediate monosubstituted methane derivatives. An economic evaluation of different methane transformation processes can be found in a 1993 review.1... 

The industrially important direct methane conversion processes comprise oxidative coupling, reductive coupling including pyrolysis reactions, partial oxidation, halogenation and oxyhalogenation,26 and ammoxidation. Other direct conversions include alkylation, electrophilic substitution, and C-H bond activation over various complex and super acid catalysts. Several of these direct conversion technologies remain to be exploited to achieve their full commercial potentials. 

Direct Methane Conversion to Hydrocarbons and Chemical Derivatives... 

Kuo, J. C. W., and Ketlar, A. D., Evaluation of Direct Methane Conversion To Higher Hydrocarbons and Oxygenates, Final Report DOE Contract DE-AC22-86PC90009, 1987. 

Fox, J. M., Chen. T. P, and Degen, B. D., Direct Methane Conversion Process Evaluation, Final Report, U.S. Department of Energy Contract DE-AC22-87PC79814, August 1988. 

A. Andersen, J.M. Dahl, KJ. Jens. E. Rytter, A. Slagtem, and A. Solbakken, Hydrogen acceptor and membrane concept for direct methane conversion, Catal. Today 4 389 (1989). S. Uemiya, N. Sato, H. Ando, T. Matsuda, and E. Kikuchi, Promotion of methane steam reforming by use of palladium membrane, Sekiyu Gakkaishi JJ 418 (1990). 

Direct Methane Conversion by Oxidative Processes, ed. E.E. Wolf, Van Nostrand Reinhold Catalysis Series, New York, 1991... 

Several other laboratories 1n Japan are becoming Increasingly Involved 1n the direct methane conversion catalysis. Several poster papers and papers at this symposium are a good evidence 1n support of this observation. 

The author 1s optimistic that with the continued worldwide efforts 1n the direct methane conversion area a commercial process will become technically feasible 1n the 1990s. 

Numerous direct methane conversion processes can be divided into four groups ... 

Summary of Economic Results. - Direct conversion processes were compared with conventional MTG or Fischer-Tropsch technology via synthesis gas. Of the three direct methane conversion technologies studied, oxyhydrochlorination, followed by oligomerization of methyl chloride to gasoline, showed the lowest cost and best economics. 

The rewards for converting light hydrocarbon gases to liquid fuels are clearly great however, many technical challenges remain for direct methane conversion to be practiced economically. The successful process will undoubtedly combine chemistry with creative engineering to handle the "demanding reactions. 

Department of Chemical Engineering, University of Colorado, Boulder. Direct Methane Conversion to Methanol, Quarterly Status Report, October 1, 1992-December 31, 1992. Report No. DOEMC271153343, Contract No. FG2190MC27115. Washington, DC U.S. Department of Energy, 1993. 

Cheng, J., Li, Z., Haught, M., and Tang, Y. (2006) Direct methane conversion to methanol by ionic liquid-dissolved... 

Recently, substantial research activity has been conducted in the area of CH4 conversion without the use of synthesis gas. We classify such processes as "Direct Methane Conversion." They have the potential of being more energy-efficient since they bypass the energy-intensive step of synthesis gas formation. 

Kuo, J.C. W. (1987) Evaluation of Direct Methane Conversion to Higher Hydrocarbons and OxygenatesMobil Res. Dev. Corp., DOE final report DOE/PC/90009-3 (DOE Contract No. DE-AC22-86PC90009, Aug.). 

Kuo, J.C. W. (1992) Chapter 15. Engineering Evaluation of Direct Methane Conversion Processes , in E.E. Wolf (ed.), Methane Conversion by Oxidative Processes, Van Nostrand Reinhold Catalysis Series, Van Nostrand Reinhold, New York, NY. 

When assessing the industrial potential, the results for "direct methane conversion should be compared with those proven for the "indirect" technologies via synthesis gas. 

In other words, a direct methane conversion process should have a C02-yield substantially lower than 20 C-atom % in order to represent a break-through compared to the indirect route. 

Gesser HD, Hunter NR. The direct conversion of methane to methanol (DMTM). In Wolf EE, editor. Direct methane conversion by oxidative processes fundamental and engineering. N.Y. Van Nostrad 1992. p. 402-25. 

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