Oxidative coupling of methane over mixed metal oxide catalysts: Steady state multiplicity and catalyst durability

SnO2Based Catalysts with Low‐Temperature Performance for Oxidative Coupling of Methane: Insight into the Promotional Effects of Alkali‐Metal Oxides

“…The typical indirect ways include methane steam reforming, dry reforming, and partial oxidation, during which, methane is first converted into syngas, and then synthesized into higher value hydrocarbons by the Fischer–Tropsch reaction . The typical direct ways include nonoxidative methane conversion to aromatics,, and oxidative coupling of methane (OCM) to C 2 hydrocarbons . For indirect conversion of methane, multiple steps are required, which obviously makes the technological process more complicated.…”

“…Since Keller and Bhasin first reported their work on OCM in the early 1980s, a lot of work on screening active and selective catalysts has been performed. The investigated catalysts can be divided roughly into two groups, the nonredox and the redox types.…”

Scale‐up analysis of autothermal operation of methane oxidative coupling with La2O3/CaO catalyst

“…The highly exothermic nature of the oxidation reactions in OCM may lead to complex ignition and extinction behavior with different reactant conversion as well as product distribution under the same operating conditions. The ignition–extinction behavior of OCM was first observed in laboratory scale experiments by Annapragada and Gulari and then also reported by many other groups, see for example, Noon et al, Lee et al, Sarsani et al, and Aseem et al These studies on the ignition–extinction and hysteresis behavior motivated the investigation of autothermal operation (AO) for OCM scale‐up . In steady‐state AO, there is no heat addition to the reactor and there is no intentional heat removal by cooling.…”

Catalyst screening for the oxidative coupling of methane: from isothermal to adiabatic operation via microkinetic simulations

“…This seems to point to adiabatic fixed-bed reactors, rather than isothermal multi-tubular ones, as a viable option for large-scale OCM implementation 20 . While a few related studies have been carried out decades ago [21][22][23] , adiabatic OCM reactors have recently received increasing academic and industrial attention [24][25][26][27][28][29][30][31][32][33] . The main driver is the exploitation of the reaction exothermicity to lower the inlet temperature required and, ideally, operate the reactor autothermally.…”

“…As described elsewhere 36, , perfect isothermicity, which is often claimed in publications, is actually very hard to realize in OCM fixed-bed setups. On the other hand, due to heat losses 33 , perfect adiabatic operation is difficult to achieve in bench-scale setups, while heat losses become negligible on the industrial-scale 24 . Simulated performance data can level out non-idealities in reactor operation and enable a direct comparison of intrinsic performances of different catalysts.…”