SAMARIUM OXIDE CATALYST - FORMATION, CHARACTERIZATION AND ACTIVITY TOWARDS PROPAN-2-OL DECOMPOSITION - AN IR SPECTROSCOPIC STUDY

IR spectroscopy has been used to study the gas-phase reaction products from the dehydrogenation-dehydration of propan-2-ol over Sm2O3 at temperatures between room temperature and 400 degrees C. Sm2O3 was shown to be a Selective dehydration catalyst at 250 degrees C with decomposition of propan-2-ol to propene (ca. 90%). The Sm2O3 catalyst was obtained as a final decomposition product of Sm(CH3CO2)(3).4H(2)O. The thermal decomposition processes up to 800 degrees C were characterized by the thermogravimetry (TG), differential thermal analysis (DTA), X-ray diffraction (XRD) and IR spectroscopy. The compound dehydrates in two steps at 125 and 170 degrees C and recrystallizes at 195 degrees C. At 350 degrees C, the anhydrous acetate decomposes to SmO(CH3CO2) via the intermediate Sm(OH)(CH3CO2)(2). At 450 degrees C two different phases of Sm2O2(CO3) are obtained which when further heated to 675 degrees C form Sm2O3. Surface area measurement and scanning electron microscopy showed that the final product,Sm2O3, at 800 degrees G has a surface area of 35 m(2) g(-1) and is a crystalline porous material.