INVESTIGATING THE SMSI (STRONG METAL-SUPPORT INTERACTION) EFFECT ON SUPPORTED RU-MN BIMETALLIC CATALYSTS BY SSIMS, TEM, GC AND AAS

The SMSI effect on Ru:Mn bimetallic alloy system supported on high sur face area TiO2 support and prepared by co-impregnation method was inve stigated. Two sets of samples with 20% Mn loading why were prepared on e reduced at 723 K (HTR) and other at 523 K (LTR). The prepared suppor ted system was characterized using SSIMS (Static Secondary Ion Mass Sp ectrometry), TEM (Transmission Electron Microscopy) and Selective Chem isorption. The carbon monoxide hydrogenation was performed using a sin gle pause flow reactor system. The hydrocarbon products were analysed using a GC (Gas Chromatography). The analytical studies reveal the CO chemisorption suppresses on the samples reduced at 723 K. The SSIMS te chnique indicates the presence of TiOx species forming two new surface sites TiOx-Ru and TiO-Mn. On TEM study these new species were found t o be located at the immediate vicinity of metal particles. The increas e in methanation activity and product selectivity on samples reduced a t 723 K as compared to the samples reduced at 523 K were possibly caus ed due to the presence of these new surface sites. These new surface s ites modify the surface geometry electronically.