Experimental and modeling study on a packed-bed membrane reactor for partial oxidation of methane to formaldehyde

A conventional fixed-bed reactor and a hybrid packed-bed membrane reactor are used to investigate the selective oxidation of methane to formaldehyde over a Mo-Co-B-O/SiO₂ catalyst at atmospheric pressure and in the reaction temperature range of 883-963 K. The reaction kinetic rate expressions have been determined by simulating the measured relationships of conversions and selectivities in the fixed-bed reactor. A zirconia/α-alumina porous membrane packed with the Mo-Co-B-O/SiO₂ catalyst is used as a distributor of reactants in the hybrid membrane reactor. A theoretical model solved by the numerical method of orthogonal collocation has also been developed for the membrane reactors to simulate the experimental data. The effects of reaction process operation conditions and membrane pore sizes on the performance of the inert membrane reactor are examined. The prospects of commercial applications for methane partial oxidations are also discussed.