Hydrous titanium oxide

Anatase form is obtained by hydrolytic precipitation of titanium(IV) sulfate on heating. The mineral ilmenite is treated with concentrated sulfuric acid. Heating the sulfate solution precipitates hydrous titanium oxide. The precipitate is calcined to expel all water. 

Titanates and silico-titanates The oxide and hydroxide of titanium are effectively used in applications of removing metal ions from water. Early studies (since 1955) have shown that hydrous titanium oxide is the most appropriate material for extracting uranium from seawater, whereas titanates and hydrous titanium oxide are suitable for removing strontium. 

HTO Catalyst Preparation. Hydrous titanium oxide ion exchangers are amorphous inorganic compounds synthesized in the form of salts of weak acids represented by the empirical formula C(TixOyHz)n, where C is an exchangeable cation. HTO catalysts can be prepared by a technique that consists of synthesis of sodium hydrous titanate ion exchange material followed by exchanging active metal ions for the sodium. The synthesis involves three steps ... 

DOSCH ET AL. Hydrous Titanium Oxide-Supported Catalysts... 

The first 15-20 years of the marine uranium projects were involved with the development of hydrous titanium oxide-based sorbents. During the last 10-15 years, directions of this study have changed and the preparation mainly of poly(acrylamidoxime) resins and their modifications has been sought. 

The technological aspects of hydrous titanium oxide production were developed in Great Britain. This product is obtained in irregular granular form by precipitation with basic titanium sulfate or chloride solutions. After the precipitation step further granulation of the precipitate is obtained using different methods. A typical product composition is 60% Ti02, 30% HjO, and 10% a mixture of other components, includ-... 

Change in the selectivity patterns of transition metal ion/H+ systems has been encountered with the amorphous and anatase types of hydrous titanium oxides with different crystallinities [24]. Potassium titanate, KjO nXi02 (n = 2-4), in particular, exhibits a layered structure. Fibrous titanic acid, H2Ti409 nHjO, is obtained by acid treatment of fibrous K2Ti409 nH20 and shows higher selectivity for K, Rb and Cs than the amorphous titanic acid [206]. 

Manganese dioxide, sodium nickel hexacynaoferrate, hydrous titanium oxide, zirconium phosphate, ferric hydroxide, different commercial sorbents... 

Chelating polymers, hexacyanoferrates, manganese dioxide, hydrous titanium oxide... 

Although strontium is one of the major metal ion constituents in sea water, its concentration of 8.1 mg/1 is about 50 times lower than that of calcium. No procedures are known for a commercial recovery of strontium from sea water. Strontium can be extracted from sea water along with uranium and other elements by hydrous titanium oxide. However, only 120-fold concentration has been reached... 

Lead compounds such as lead naphthalene tetracarboxylate, lead pyrophosphate, lead stannate, lead sulfide, and others which are not listed in Table 3, were proved to be effective uranium sorbents in sea water 131). However, sorbent materials containing toxic metals must be excluded with respect to sea contamination which would be inevitable even in the case of slight solubility. On the other hand, many metal compounds are decomposed in sea water by hydrolysis and carbonate formation. Among the inorganic sorbents presented in Table 3, hydrous titanium oxide and... 

Fig. 6. Function of hydrous titanium oxide as cation and anion exchanger in dependence on pH 103>...

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