INFRARED SPECTROSCOPIC STUDIES OF THE FORMATION AND CATALYTIC ACTIVITY OF ND2O3

Nd2O3 catalyst was obtained as a final product of the thermal decomposition of Nd(CH3COO)3.2H2O. The decomposition processes up to 800-degrees-C were characterized by means of TG, DTA, XRD, and IR spectroscopy of the gas and solid phase products. The activation energy values were determined non-isothermally for thermal events involved in the decomposition course. The results indicate that Nd(AcO)3 is completely decomposed to Nd2O3 at 670-degrees-C through five different intermediates; Nd(OH)(CH3COO)2 at 310-degrees-C, NdO(CH3COO) at 320-degrees-C, Nd2(CO3)3 at 350-degrees-C, Nd2O(CO3)2 at 385-degrees-C, and Nd2O2(CO3) at 410-degrees-C. The oxide, Nd2O3, obtained at 800-degrees-C possesses higher surface area (30 m2 g-1) than that obtained at 1000-degrees-C (10 m2 g-1). Thus, the oxide obtained at 800-degrees-C was tested qualitatively and quantitatively as a catalyst towards the decomposition of 2-propanol at 100-400-degrees-C by IR-spectroscopy. The results indicate that Nd2O3 catalyses 2-propanol dehydrogenation (forming acetone) at < 300-degrees-C and dehydration (forming propene) at > 250-degrees-C. At > 350-degrees-C, acetone was involved in a secondary surface reaction, presumably with the surface hydroxyl groups, to give CH4 and CO2 in the gas phase.