Two series of Ni (2.5 to 7.5 wt%) and Ce (6 wt%) containing SBA-15 catalysts were prepared and tested in dry reforming of methane, a promising route for the production of syngas. Both Ni and Ce species were introduced in the organized mesoporous silica support in the form of nitrate salts using the "two solvents" procedure that is known to favor metal dispersion inside the porosity. Samples characterizations by N 2 sorption, SAXS, XRD, SEM and TEM indicate good preservation of the porosities after Ni deposition and calcination as well as formation of NiO nanoparticles entrapped in the porous channels. In the cerium-enriched samples, the CeO 2 nanoparticles are also highly dispersed. After reduction, all the catalysts show high activity and selectivity towards H 2 and CO at atmospheric pressure with full CH 4 conversion below 650 o C. In these conditions, there is no significant promotional effect by ceria. Moreover, prolonged tests performed at 500 o C for 12 hours reveal a high stability of the catalysts. The absence of deactivation throughout the catalytic run at this temperature agrees with the low carbon amount detected after test and with the limited sintering of the Ni nanoparticles in the used catalysts. The positive effect of the SBA-15 mesoporous channels towards stabilization of the supported particles is discussed.

Highlights:  Co nanoparticles are stabilized against sintering in the mesopores of SBA-15 during dry methane reforming.  The decrease of reduction temperature in presence of Rh leads to more numerous Co species confined in the pores.  Deactivating carbons are formed in lower amount in presence of both rhodium and cobalt.

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