The current study investigates a chemical‐looping‐based oxidative dehydrogenation (CL‐ODH) concept for ethane‐to‐ethylene conversion. In this cyclic redox scheme, an oxide‐based redox catalyst is used to selectively combust hydrogen from ethane dehydrogenation. As the hydrogen product limits ethane conversion, in situ oxidation of hydrogen enhances the ethane conversion and ethylene yield. Moreover, heat required in ODH is compensated by re‐oxidation of the oxygen‐deprived redox catalyst, enabling auto‐thermal operation for the overall process. Compared to steam cracking, CL‐ODH can potentially achieve higher efficiency with lower CO2 and NOx emissions. Silica and magnesia‐supported manganese oxides are investigated. It is determined that unpromoted Mn/SiO2 and Mn/MgO redox catalysts exhibit low selectivity towards ethylene. The addition of promoters such as sodium and tungsten renders effective redox catalysts with satisfactory activity, selectivity, oxygen carrying capacity, and redox stability.

As much as two-thirds of the natural gas reserves in the world are located in areas where the means of transportation of this resource are not available. Because this "remote gas" cannot be easily brought to market, it has little value. For this reason new technologies are being developed to convert this gas, mostly methane, to higher valued, transportable products. Gasoline and distillate are the only markets large enough to accommodate the size of these reserves. Currently, the Mobil MTG process is being used in New Zealand for gas to gasoline conversion. This paper discusses a series of promoted metal oxide catalysts that transform methane to higher hydrocarbons. The products are olefinic with ethylene as the major component. The process is performed oxidatively either in a cyclic redox mode or as a catalytic reaction of methane and oxygen. At 25% methane conversion 70-75% C2+ selectivities are obtainable. This first-stage product may be passed over a second-stage acid zeolite catalyst to produce a gasoline range product.

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Directly upgrading natural gas is limited by the stability of its primary component, methane, and process economics. Since the 1980s, oxidative coupling of methane (OCM) has shown potential to produce ethylene and ethane (C2s). The typical OCM approach catalytically converts methane to C2 products using molecular oxygen, reducing process efficiency. To overcome this, chemical looping OCM converts methane to hydrocarbons via intermediate oxygen carriers rather than gaseous cofed oxidants. The chemical looping approach for OCM has been studied mechanistically for the first time with a Mn–Mg-based catalytic oxygen carrier (COC). The COC delivered stable performance in a fixed bed for 100 cycles for more than 50 h with a 63.2% C2 selectivity and 23.2% yield. These experimental results and original process simulations of an OCM chemical looping system for C2 or liquid fuel production with electricity cogeneration present a direct method for methane utilization.