Thorium IV oxide

In a chemical vapor deposition (CVD) variant of conventional powder metallurgy processing, fine chromium powder is obtained by hydrogen reduction of Crl2 and simultaneously combined with fine thorium(IV) oxide [1314-20-17, H1O2, particles. This product is isostaticaHy hot pressed to 70 MPa (700 atm) and 1100°C for 2 h. Compacts are steel clad and hot roUed to sheets (24). 

Rothe, J Denecke, M. A., Neck, V., Muller, R. Kim, J. I. 2002. XAFS investigation of the structure of aqueous thorium(IV) species, colloids, and solid thorium(IV) oxide/hydroxide. Inorganic Chemistry, 41, 249-258. 

Felmy, A. R., Rai, D. Mason, M. J. 1991. The solubility of hydrous thorium(IV) oxide in chloride media development of an aqueous ion-interaction model. Radiochimica Acta, 55, 177-185. 

Question 10.4 Thorium(iv) oxide has a melting point of 3390 °C. Explain why. 

Both uranium(IV) oxide and thorium(IV) oxide react with phosgene, at 450 C and 650 C respectively, according to [359a,360] ... 

Indeed, for thorium(IV) oxide, the process has been shown to occur in two steps [1092], and replacement of COCl with a CO-Clj mixture results in the process stopping at the oxide chloride stage [1092,1350a] ... 

The solubilities of nickel and thorium(IV) oxides in molten KF-LiF mixture at 550 °C were investigated by the potentiometric titration method using a membrane oxygen electrode [379, 380]. The solubility product of NiO in the fluoride melt was equal to 1.3 X 10-6, which considerably exceeded the corresponding values in the chloride melts discussed above. The solubility of NiO seemingly increased owing to the fixation of Ni2+ cations in strong fluoride complexes. 

Tetrachlorodibenzo-/)-dioxin Thorium(IV) oxide Triethylenethiophosphoramide Reasonably Anticipated to be Human Carcinogens Acetaldehyde 2-(Acetylamino)fluorene Acrylamide Acrylonitrile... 

Under the experimental conditions described above, zinc oxide, lanthanum(III) oxide, cadmium oxide, and thorium-(IV) oxide are partially converted to the corresponding chlorides. 

Thorium (IV) oxide is obtained by thermal decomposition of thorium oxide hydrate (which is precipitated with ammonia) or salts of oxygen-containing acids. The nitrate and oxalate are especially suitable as starting materials, while the sulfates give off the last traces of SO3 only with difficulty. 

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