Titanium oxidation, description

In a December 1974 report, Battelle Pacific Northwest Laboratory [B2] summarized the principal processes that had been proposed for extracting uranium from seawater and gave references to more detailed descriptions of these processes. That report concluded that the most promising process was the selective adsorption of uranium from seawater on hydrous titanium oxide (titania). 

The vicar refers to his friend the famous mineralogist Johan Hawkins, who says that he has never seen a mineral like this, ft must contain an unknown metal Gregor proposes that the name of this new element shall be menachanite after the finding-place. Gregor s description of the dark mineral from the Menachan valley and his correct supposition that it contained a new element was not paid much attention, despite its publication in Crell s Annalen. The discovery was forgotten. Gregor died of tuberculosis in 1817. Today we know that Gregor s mineral is identical with ilmenite, iron titanium oxide FeTiO,. 

The titaniuin oxides are of considerable technological interest, so different theoretical studies of electronic and atomic structure and properties have been performed both for Ti02 [100,323,596,597] and Ti20s [598,599] crystals. We are not aware of the existence of the electronic-structure calculations of TiO. The available publications focus attention primarily on description of the band structure and phase stabihty of titanium oxides and restrict the discussion of the nature of chemical bonding in these compounds to an analysis of Mulhken atomic charges and overlap populations. 

A very detailed description of the chemistry associated with titanium oxygen systems is available [4]. The material is very thermally stable, and extremely resistant toward chemical degradation. It can be partially reduced when heated in the presence of hydrogen or carbon monoxide, the products being either lower oxides or mixtures of titanium carbide and lower oxides. Reduction by active metals (Na, K, Ca, or Mg) can... 

As stated in the anode descriptions earlier, there are also two NACE test methods for cathodic protection anodes. These are TM 0294 on embeddable anodes (mixed metal oxide coated titanium, mesh, ribbon, tnbes, rods and conductive ceramic tubes) and TMO1105-2005 on organic-based condnc-tive coating anodes. In addition there is a specification for applying thermal sprayed zinc anodes to concrete American Welding Society (2002). 

For a detailed description of anodic oxidation of titanium and its alloys the reader may refer to a review by Aladjem (1973). 

Because this chapter focuses on molecular transition metal complexes that catalyze the formation of polyolefins, an extensive description has not been included of the heterogeneous titanium systems of Ziegler and the supported chromium oxide catalysts that form HDPE. However, a brief description of these catalysts is warranted because of their commercial importance. The "Ziegler" catalysts are typically prepared by combining titanium chlorides with an aluminum-alkyl co-catalyst. The structural features of these catalysts have been studied extensively, but it remains challenging to understand the details of how polymer architecture is controlled by the surface-bound titanium. This chapter does, however, include an extensive discussion of how group(IV) complexes that are soluble, molecular species polymerize alkenes to form many different types of polyolefins. 

Chen, G. Z., D. J. Fray, and T. W. Farthing. Direct Electrochemical Reduction of Titanium Dioxide to Titanium in Molten Calcium Chloride. Nature 407 (2000) 361-364. First description of the FFG-Cambridge method—possibly game-changing procedure for reducing metal oxides. 

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