Electron-transfer and the catalytic activity of oxide catalysts. Part 1.—Electron-transfer activity of alumina catalysts and their activity for the catalytic exchange of the hydrogen in propane with deuterium

摘要: The exchange reaction of propane with deuterium has been studied over a number oxide surfaces. Exchange activity in aluminas is virtually confined to catalysts activated the temperature range 400–800°C, sharp maximum around 530–560°C. Since these temperatures are well excess those leading surface area and adsorption (∼350°C), some specific property must be involved reaction. pure alumina which correlates best hydrogen-deuterium Lewis acidity. Blocking experiments electron-acceptor molecules show, however, that reducing centres on play an essential role. In each case weaker sites important. hydroxyl groups not apparently as vehicles for deuterium, hydrogen between hydrocarbon intermediate step reaction. Silica-alumina containing less than ∼80% Al2O3 show no detectable propane-deuterium at room under any conditions activation only moderate rates higher temperatures. On all oxides stepwise process involving replacement one atom time.