| Abstract: | Pure silica MCM-41 mesoporous molecular sieve material was synthesised and characterised by in situ synchrotron XRD, TEM,
TGA/DTA and DRIFTS techniques. In situ energy dispersive XRD (EDXRD) confirmed the exact nature of the pore diameter of MCM-41
and the change in crystal structure on calcination. The IR band at 1057 cm-1 of as-synthesised MCM-41 was shifted by 14 cm-1 on heating to 673 K due to increased condensation of silanol groups to form Si-O-Si bridges. Calcined MCM-41 materials were
used to support Pd, and the catalytic activities for 1-hexene and benzene selective hydrogenation were investigated. The Pd/MCM-41
catalyst showed high activity in hydrogenation of 1-hexene at an inlet reaction temperature of 298 K, but did not show any
activity in hydrogenation for benzene. TEM results for the reduced Pd/MCM-41 catalysts revealed that the average Pd particle
size was around 2-2.5 nm and these particles were located in the pores of MCM-41 and showed good distribution. TPR measurements
showed that about 70% of palladium oxide (PdO) loading in the calcined catalysts was reduced at sub-ambient temperature.
This revised version was published online in July 2006 with corrections to the Cover Date. |
