Thermodynamic Limitations of the Catalyst Design Space for Methanol Production from Methane

Abstract

Current efforts to overcome the challenges of direct methane to methanol processes have focused on designing heterogeneous catalysts that perform methane partial oxidation using cheap and abundant oxidants such as molecular oxygen and water. An evaluation of the thermodynamic limitations of methanol production with the use of these oxidants is required to understand the maximum possible conversion and selectivity for a given feed composition and temperature. When O2 is present, the formation of the most thermodynamically stable product, carbon dioxide, must be inhibited. At practical temperatures for moderate scale processes, water as the sole oxidant results in extremely low steady‐state methane conversion, but higher yields can be achieved with coupled surface reactions. This work evaluates these thermodynamic challenges and opportunities for catalysts that can selectively oxidize methane to methanol with oxygen and water and discusses routes for achieving high methanol yields.

Selective Oxidation of Methane to Methanol over Ceria‐Zirconia Supported Mono and Bimetallic Transition Metal Oxide Catalysts

“…Based on the observation that surface methoxy/alkyl groups were formed during methane activation and a thermodynamic analysis that indicated that an oxidant like O 2 is needed for methanol production, [1c] we hypothesized that the direct conversion from methane to methanol can be achieved by feeding steam and oxygen together with methane. Under the reaction conditions reported, continuous direct conversion from methane to methanol was achieved for all catalysts.…”

DFT Mechanistic Study of Methane Mono-Esterification by Hypervalent Iodine Alkane Oxidation Process

“…[28] There is a variety of other recent literature showing methane partial oxidation to methanol, syngas, or other products. [29][30][31][32][33][34][35][36][37][38][39][40][41][42][43] Our work on the partial oxidation of methane has focused on the search for processes efficient under less acidic environments, in particular trifluoroacetic acid (TFAH). [44] For instance, we have characterized a number of rhodium complexes with C-H activation ability in TFAH.…”

Catalytic Oxidation of Methane to Oxygenated Products: Recent Advancements and Prospects for Electrocatalytic and Photocatalytic Conversion at Low Temperatures

“…[12] Natural gas has been exploited from shale gas recently, the amount of which is estimated to be more than 7299 trillion cubic feet. [13][14][15][16][17] Methane also could be naturally generated from biosystems as marsh gas through the anaerobic digestion of crops, wastes and residues. [18,19] Human activities, such as coal mining, natural gas or petroleum drilling and breakdown of garbage in landfills, significantly contribute to the release of CH 4 .…”