Temperature-programmed desorption titania

Temperature-programmed desorption (TPD) under ultra-high vacuum conditions of CO and from polycrystalline nickel surfaces containing varying amounts of titania showed that the effects of titania are short-ranged. 

The experimental techniques and apparatus have been described in detail elsewhere. (8, 9) Titania and niobia were deposited onto the clean metal foils by vaporizing either a Ti-Ta alloy wire or a niobium wire in 10-7 Torr H2 at 800K. Auger electron spectroscopy (AES) was used to determine the oxide coverages, and temperature programmed desorption (TPD) was used to determine the effect of the oxide layers on the adsorption of CO and H2. Methanation rates were measured in a side chamber which allowed the sample to be characterized by AES before and after rates were measured. All rates were measured with 100 Torr CO and 400 Torr H2, and conversion to methane was always kept less than 1%. 

Fig. 15. Temperature-programmed desorption of carbon monoxide from nickel surfaces containing titania. (After Ref. 122.)...

Gun ko, V.M., Zarko, V.L, Chuikov, B.A. et al. 1998a. Temperature-programmed desorption of water from fumed silica, titania, sUica/titania, and sihca/alumina. Int. J. Mass Spectrvm. Ion Process. 172 161-179. 

Nishide, T., T. Tanaka, T. Yabe (2004) Temperature programmed desorption analysis of sol-gel-derived titania films. Journal of thermal analysis and calorimetry. 90,373-378. 

Ceria, titania, and zirconia supported ruthenium and eopper catalysts were tested in the production of n-butanal by n-butanol oxidation. These eatalysts were characterized by means of X-ray diffraction (XRD), N2 adsorption-desorption isotherms, temperature-programmed reduction (TPR), and X-ray photoelectron spectroscopy (XPS) techniques. The activity tests were performed in a fixed bed reaetor at 0.1 MPa and 623 K and pure mixture of reactants, air and n-butanol, in stequiometric proportion was introduced to the reactor. The rathenium catalysts showed a higher activity and stability than the copper catalysts, nevertheless the copper system showed a higher selectivity toward butyraldehyde production by n-butanol oxidation. 

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