Ru/12SrO–7Al2O3 (S12A7) catalyst prepared by physical mixing with Ru (PPh3)3Cl2 for steam reforming of toluene

• Ru/S12A7 (PPH) catalysts were prepared by physical mixing with Ru(PPh3)3Cl2 and S12A7.
• PPH catalysts had higher Ru dispersion than conventional catalysts with RuCl3 nH2O.
• The N2 pre-treated PPH catalyst exhibited the highest catalytic activity and durability.

Steam reforming of toluene as a model of aromatics was performed over various Ru/12SrO–7Al2O3 (S12A7) catalysts, and the effects of Ru precursor, calcination and pre-treatment conditions on the catalytic activity and durability of Ru/S12A7catalysts were investigated. The catalytic activity of prepared Ru/S12A7 catalysts exhibited higher than that of a commercial Ru/Al2O3 (RA), despite low Ru loading. The catalysts prepared by the physical mixing of Ru (PPh3)3Cl2 and S12A7 (PPH) had higher catalytic activities than the catalysts prepared by the impregnation with RuCl3 nH2O (CL). It is interesting that the N2 pre-treated PPH and CL catalysts especially had higher catalytic activities than the H2 pre-treated PPH and CL catalysts. In their catalysts, there was a linear relationship between the catalytic activity and the Ru dispersion estimated by CO chemisorption. The catalytic activity of the N2 pre-treated PPH catalyst has little decreased with time on stream, whereas the catalytic activities of the N2 pre-treated CL catalyst and H2 pre-treated PPH catalyst gradually decreased with time on stream.