Particular titanium oxide

The high reactivity of titanium metal is disguised in normal use by its unusually corrosion-resistant protective oxide film (Chapter 16), but it must always be borne in mind by users of Ti process or laboratory equipment. In particular, titanium should not be used with pressurized oxygen pressures of oxygen of as little as 0.4 MPa have been reported to lead to ignition of Ti at ambient temperature if the oxide film is penetrated. 

The commonest gel for adsorption purposes is silica gel but measurement have also been carried out on ferric oxide, aluminium oxide, stannous oxide and titanium oxide. The characteristics of adsorption on silica gel differ somewhat from those for charcoal, particularly with respective Freundlich isotherm which holds fairly accurately. Moreover, deviation from Henry s Law even, seems to be much less than for charcoal. Water is somewhat exceptional. Silica and alumina gels are used as adsorbents for removing moisture and for controlling humidities of rooms. 

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]. 

Before the pulp can be made into paper, it is necessary to mechanically beat or refine it. It is also usually bleached with chlorine and calcium hypochlorite. Unbleached kraft pulp is used for grocery bags and heavy wrapping paper. Other materials may also be added to the pulp depending on the type of paper to be made. For book paper, fillers such as white clay and titanium oxide may be added to provide opaqueness and extra whiteness. Size may be added for stiffness and smoothness. Dyes are added for tinted papers. The specific combination of pulp and additives used to produce a particular type of paper is called the furnish for that paper. With better grades of paper, care is taken to produce a furnish that is chemically neutral (pH 7 on the acid-base scale). For a paper to have long life, it must be acid-free. 

Several technical processes have been suggested for the recovery of uranium from sea water using solid sorbents, in particular hydrous titanium oxide. The processes have partially been tested in preliminary model plants. Generally, fixed and fluidized sorbent bed operations can be distinguished. 

Methylpyridines are easily converted into the corresponding nitriles. The ammoxidation of 3-methylpyridine to nicotinonitrile has been particularly extensively investigated, mainly because of the importance of the nitrile as precursor of vitamins. The catalysts used are mostly vanadium-containing oxides, e. g. vanadium-titanium oxide [86], vanadium-zirconium oxide [87], or multicomponent systems [30,88]. Yields of more than 90% at nearly complete conversion were recently reported (e. g. 100% selectivity for vanadium oxide on titania (anatase) catalysts with V2O5 loading < 3.4 mol% [89]. 

Defines calcium titanium oxide in particular and generally all crystalline materials that exhibit a crystal structure similar to it, as with the crystalline structure of PZT. 

A comparison of the distribution profiles for the Ti-Si02 Si and Ti-Si structures by SIMS shows that higher temperatures accelerate the diffusion of silicon into titanium (until Si atoms appear on the titanium surface of the Ti-Si structures at r > 500°C) and titanium into SiO and Si. The fraction of Ti02 in the oxide layer increases with increasing temperature, particularly in the region close to the titanium-oxide layer interface, due to the decrease in the Si02 fraction. The profile of the SiO distribution is virtually unaffected by changes in substrate temperature. 

---