Zeolite-catalysed oxidation of carbon monoxide at unusually low temperatures

Theoretical identification of carbonate geometry in zeolites from IR spectra

“…The presence of carbonates was strongly confirmed in alkali and alkaline earth forms via IR analyses. The interpretation of the higher cationic mobility can also easily explain the fact of the higher CO adsorption relative to N 2 [18] due to the easy carbonate formation from CO in alkali [29] and alkaline earth [9][10][11][12][13] forms. This CO/N 2 separation cannot for example be explained by the trapdoor model [18].…”

Ion‐exchanged binuclear Ca2OX clusters, X = 1–4, as active sites of selective oxidation over MOR and FAU zeolites

“…To our knowledge, the work reported in ref 2. is the first description of oxidation activity of ZnY (or ZnFAU) as compared to the oxidation properties of the FAU types with alkaline earth cations (Mg, Ca, Sr, Ba) that were already widely investigated earlier with respect to small alkenes,3–5 toluene,6, 7 p ‐xylene,8 cyclohexane,7, 9 propane,10 and CO 11–13. The usual accepted mechanism is a stabilization in the electric field (EF) of an “oxidized molecule—O 2 ” ion pair with an essential charge transfer 3–7.…”

“…The wide range of the MOR,1, 11, 12 Y,1–13 BETA,8 ZSM‐5,8 and Linde (or A type)13 zeolites, whose cationic forms are active in oxidation processes, suggests a secondary role of the framework in the oxidation. The stability of the Ca 2 O X clusters proposed in ref 14.…”