Oxidative Coupling of Methane: Challenges for More Yield

One of the most interesting research subjects in the petrochemical industries is direct methane conversion to ethylene through the “Oxidative Coupling of Methane, OCM” process. For OCM to be economically competitive with current methods, the process must achieve C2+ selectivity and CH4 conversion of approximately 85 and 35% respectively. Both gas-phase and surface reactions have critical role in this process. In the base of OCM mechanism, there are two reaction pathways, after methyl radical is formed. The first one leads to the formation of oxygenated species (i.e. HCHO, CO, CO2) and the second one leads to the formation of C2+ hydrocarbons. The major research centers attempt to either synthesis of proper catalyst or design the reactor for process control in order to increase of ethylene selectivity. Economically, in order to maximize the reaction yield there are another remedial ways such as ethylene co-feeding, methane recycle and combine with endothermic process. By inspiration of intercellular redox reactions and dehydrogenation process, relevant enzymes, catalysts and biocatalysts that are able to either decrease reaction temperature or increase yield and selectivity, will be developed.