ELECTRON-ACCEPTOR CENTRES IN Fe–Zr/Al OXIDE CATALYSTS AND THEIR PARTICIPATION IN THE CONVERSION OF ETHANOL INTO HYDROCARBONS

Electron-acceptor (EA) and electron-donor (ED) centres in Zr/Al, Fe–Zr/Al oxide catalysts and their concentration as a function of composition of catalysts are determined using EPR spectroscopy of adserbed diphenylamine and nitrobenzene molecules. In situ EPR spectroscopy of catalysts in combination with on line chromatografic analysis of gas-phase products of the conversion of ethanol into hydrocarbons also was used. The rate of the yield of olefins as a function of the concentration of EA centres in catalysts was studied and it was established that the EA centers are the catalytically active centres of the conversion of ethanol into hydrocarbons on the aluminium oxide catalysts. The phase composition of Zr/Al, Fe–Zr/Al oxide catalysts and distribution of the catalytically active components on the surface of these catalysts were controlled using X-ray diffraction and X-ray fluorescence microscopy, accordingly