Study of oxygen chemisorption on supported oxide catalysts by adsorption microcalorimetric and electron spin resonance methods

Oxygen chemisorption heats are determined on supported V2O5/MgO and V2O5/Al2O3 catalyst containing from 1 to 15% wt. V2O5 at 25 deg C. It is shown, that during oxygen adsorption on V2O5/MgO formed is O2- with 20 kcal/mol adsorption heat and O- with adsorption heat about 60 kcal/mol, which oxidize CO at 25 deg C. The total quantity of chemisorbed oxygen goes through the maximum with increasing V2O5 content. Oxygen adsorption heats on the V2O5/Al2O3 type catalysts exceed 60 kcal/mol for all the V2O5 concentrations; O2- ions are not formed on these catalysts. The total number of of adsorbed oxygen increases with increasing V2O5 concentration