Scaled-up production of C_2 hydrocarbons by the oxidative coupling of methane over pelletized Na_2WO_4/Mn/Si02 catalysts: Observing hot spots for the selective process

摘要

The oxidative coupling of methane (OCM) to produce ethane and ethylene, valuable hydrocarbons, was scaled-up using differential, mid-scale, and bench-scale reactors with 0.030,2.73, and 40 g of packed catalysts, respectively. Organic and inorganic binders, such as methylcellulose, A1_2O_3, MgO, and TiO_2, were mixed with Na_2WO_4/Mn/SiO_2 catalyst powder to produce catalyst pellets, and TiO_2-mixed catalyst pellets exhibited the highest C_2 hydrocarbon yield despite the lowest active catalyst content. The formation of hot spots, which suppressed the selective conversion to C_2 hydrocarbons by further oxidation to CO and CO_2, was observed in the mid- and bench-scale reactors because of poor heat transfer. Inert-gas-diluted reactants and lower O_2 flow may inhibit the formation of hot spots and allow the development of industry-feasible OCM processes.