Anatase titanium dioxide

Raman spectroscopy of [INFRARED TECHNOLOGY AND RAMAN SPECTROSCOPY - RAMAN SPECTROSCOPY] pol 14) Titanium dioxide, anatase [1317-70-0]... 

The near-UV illuminated titanium dioxide (anatase) powder flow reactor, as well as the gas chromatographic methods for analysis of effluents, has been described in detail earlier [2]. The procedvu-es followed were substantially those of Luo and OUis [1], and Sauer et al. [2]. 

Heat-flow calorimetry may be used also to detect the surface modifications which occur very frequently when a freshly prepared catalyst contacts the reaction mixture. Reduction of titanium oxide at 450°C by carbon monoxide for 15 hr, for instance, enhances the catalytic activity of the solid for the oxidation of carbon monoxide at 450°C (84) and creates very active sites with respect to oxygen. The differential heats of adsorption of oxygen at 450°C on the surface of reduced titanium dioxide (anatase) have been measured with a high-temperature Calvet calorimeter (67). The results of two separate experiments on different samples are presented on Fig. 34 in order to show the reproducibility of the determination of differential heats and of the sample preparation. 

FeS04 + TiO SO4 + 2H 0. In a second step, the concentrated liquor is nucleated, diluted with H2O, and boiled until nearly all of the titanium has precipitated out in the form of flocculated titanium dioxide (anatase)... 

It should be noted that all above-mentioned results have been obtained using polycrystalline titanium dioxide (anatase, rutile) [49, 51] on the whole, the same regularities are observed during the control experiments with the monocrystalline rutile. When going from poly- to nanocrystalline Ti02 obtained by zol-gel method, the EER spectrum of the oxide substantially changes [53]. 

Titania, goethite and silica were used as adsorbents. Titanium dioxide (anatase) and silica powders were obtained commercially. Goethite was prepared from an FefNC solution by the precipitation of ferrihydrite.8 The suspension was held in a closed flask at 70°C for 60 hours. During this period the red brown suspension of ferrihydrite was converted to a yellow brown goethite. These oxides were washed with double distilled water to remove impurities, until the supernatant conductivity was below 2pS x cnT1. 

Anatase, brookite and rutile are three polymorphs of titanium dioxide. Anatase is a kind of thermodynamically metastable form while rutile is a kind of stable one. Anatase can transform irreversibly to rutile at elevated temperatures ranged from 400 to 1200 °C according to particle size, morphology and additives. The solid-state phase transformation behavior has been widely investigated while the phase evolution between anatase and rutile under hydrothermal condition has been little paid attention to so far [5]. In this work, the structural evolution from anatase to rutile under milder hydrothermal conditions is proposed as well [7, 10]. 

Schindler, P. W. and Gamsjaeger, H. Acid-base reactions of the titanium dioxide (anatase) - water interface and the point of zero charge of titanium dioxide suspension, Kolloid - Z. Z. Polym. 250, 759-763 (1972). 

Wachs, l.E. and Chan, S.S. (1984) In situ characterization of small vanadium oxide (V2OS) crystallites supported on titanium dioxide (anatase). Applied Surface Science, 20 (1-2), 181-5. 

Rutile titanium dioxide Anatase titanium dioxide 50% titanium calcium base 30% titanium calcium base 370-410 (PVC)l/3 298-330 (PVC)l/3 222-213 (PVC)l/3 127-106 (PVC)l/3... 

Ti02[A] TITANIUM DIOXIDE (ANATASE) 1693 UCI6 URANIUM HEXACHLORIDE 1737... 

Figure 6. Powder x-ray diffraction pattern of titanium dioxide, anatase phase. The intensity scale is presented in arbitrary units.

Crystallographic Data for the 10 Most Intense Scattering Peaks of Titanium Dioxide, Anatase Phase... 

The most serious problem however relates to the relatively large bandgap of titanium dioxide. Titanium dioxide (anatase) has a bandgap energy of... 

Titanium dioxide, anatase n. Ti02. Pigment white 6 (77891). A high opacity, bright... 

The diffraction patterns of the decomposed aerosol products of TiO and Fe-TiOj obtained by spray pyrolysis showed poor crystallinity. Specimens were therefore further calcined at temperatures of 823K, 873IG 973K and 1073K in air for a period of 2 hours in order to improve their crystalline structure. Fig.1. shows the x-ray diffraction patterns of titanium dioxide (anatase), and a series of iron-titanium oxide specimens of nominal Fe(IlI) concentration equivalent to 0.1, 1, 2, 5 and 10 atom%, prepared by the spray pyrolysis method and subsequently calcined at 823K in air for 2 hours. 

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