Nuevos Catalizadores para la Producción de Hidrógeno en un Reactor de Membrana

JOHN MÚNERA, MARCOS KIHN, CARLOS CARRARA, SILVIA IRUSTA, LAURA CORNAGLIA

Mérida-Yucatan-Mexico

Simposio; XIX SIMPOSIO IBEROAMERICANO DE CATÁLISIS; 2004

The dry reforming of methane as a source of H2 was performed using a novel catalyst, Rh/La2O3-SiO2, and Rh/La2O3 in a hydrogen-permeable membrane reactor. The catalysts were characterized by DRX, FTIR, LRS and H2 chemisorption. The effect of the operation variables upon the performance of the membrane reactor was also studied. The Rh(0.6%)/La2O3-SiO2 catalyst was the best formulation. Operating at 823 K, both the methane and CO2 conversions were 40 % higher than the equilibrium values producing 0.5 mol H2/mol CH4. This catalyst, tested at W/F three times lower than the Rh(0.6%)/La2O3, showed a similar performance. Increasing the sweep gas flow rate as well as decreasing the permeation area significantly affect both the methane conversion and the H2 production. The better performance of Rh(0.6%)/La2O3-SiO2 is related to the high dispersion and turnover frequency of this formulation. In all cases, the activity of the Rh catalysts remains constant after 100 hours on stream at 823 K. The presence of tiny amounts of graphite only detectable through LRS does not endanger membrane stability.