FT-IR spectroscopy is employed to investigate the methane dissociation and methane partial oxidation over the Rh/SiO 2 catalyst. When CH 4 is adsorbed onto the catalyst surface, it dissociates into adsorbed CH x (x=1～3) and atomic hydrogen on Rh surface. Atomic hydrogen can diffuse from Rh surface to SiO 2 surface where a proton exchange reaction of H with the surface Si-OH occurs, or it reacts with the lattice oxygen of SiO 2 to form new Si-OH.
The catalytic activity of the industrial catalyst A 110 3 after modification with Mn 2+ was found to be increased to about 17.4%. The ammonia synthesis was carried out under conditions of 2 1 MPa, 14400 h -1 and 300 ℃. The increase in activity is explained in terms of the weakness of Fe NN or Fe—N bond based on the XPS and TPD MS results.
Ni/Al\-2O\-3 catalyst was prepared by impregnating α \|Al\-2O\-3 with Ni(NO\-3)\-2 aqueous solution, and characterized by temperature programmed reduction (TPR), X\|ray diffraction (XRD) and X\|ray photoelectron spectroscopy (XPS) techniques. The effects of Ni content, calcination temperature and activation conditions (such as reduction temperature and time) on coke deposition on the catalyst were studied. The results showed that the interaction between Ni and Al\-2O\-3 benefits to improve the stability and the resistance to coke deposition of the catalyst, though the activity of the catalyst was decreased to a certain extent.
