Titanium rutile, anatase

The main oxides are the dioxides. In fact, Ti02 is by far the most important compound formed by the elements of this group, its importance arising predominantly from its use as a white pigment (see Panel, p. 959). It exists at room temperature in three forms — rutile, anatase and brookite, each of which occurs naturally. Each contains 6-coordinate titanium but rutile is the most common form, both in nature and as produced commercially, and the others transform into it on heating. The rutile... 

Titanium dioxide exists in nature as three different polymorphs rutile, anatase and brookite. This material has been extensively studied during the last few decades due to its interesting physical properties and numerous technological applications. Rutile and anatase (a popular white pigment) are widely used in photocataly s and as sensors. Both of them have had new structural and electronic applications suggested recently (see for a review). 

Titanium Dioxide (Titania, Titanium White, Rutile, Anatase, Brookite, Titanic Anhydride, Titanic Acid Anhydride, Titanic Oxide). Ti02, mw 79.90, Selected Parameters of the Allotropic Forms of Ti02... 

The coordination theory, which has been applied successfully2 to brook-ite, the orthorhombic form of titanium dioxide, is based on the assumption that the anions in a crystal are constrained to assume positions about the cations such that they indicate the corners of polyhedra of which the cations mark the centers. These polyhedra are the fundamentally important constituents of the crystal retaining their form essentially, they are combined by sharing corners, edges, and faces in such a way as to build up a crystal with the correct stoichiometrical composition. Thus in rutile, anatase, and brookite there occur octahedra of oxygen ions about titanium ions in rutile each octahedron shares two edges with adjoining octahedra, in anatase four, and in brookite three. 

Titanium dioxide (E171, Cl white 6) is a white, opaque mineral occurring naturally in three main forms rutile, anatase, and brookite. More than 4 million tons of titanium dioxide are produced per year and it is widely used for industrial applications (paints, inks, plastics, textiles) and in small amounts as a food colorant. ° "° Production and properties — Titanium oxide is mainly produced from ilmenite, a titaniferous ore (FeTiOj). Rutile and anatase are relatively pure titanium dioxide (Ti02) forms. Titanium oxide pigment is produced via chloride or sulfate processes via the treatment of the titanium oxide ore with chlorine gas or sulfuric acid, followed by a series of purification steps. High-purity anatase is preferred for utilization in the food industry. It may be coated with small amounts of alumina or silica to improve technological properties. 

There are three crystal structures of titanium dioxide rutile, anatase, and brookite. The most active phase is rutile, which has a tetragonal structure [133], as shown in Figure 8.5 [134],... 

Rutile and anatase are used in photocatalysis and as catalyst supports and we describe some important structural features later. The titanium-oxygen system plays a key role in understanding stoichiometric variations. The highest oxide, Ti02, is polymorphic and the four known crystal structures are rutile, anatase, brookite and a high-pressure form similar to a-Pb02. 

Titanium dioxide [13463-67-7], Ti02, Mr 79.90, occurs in nature in the modifications rutile, anatase, and brookite. Rutile and anatase are produced industrially in large quantities and are used as pigments and catalysts, and in the production of ceramic and electronic materials. 

Titanium dioxides The most common forms of titanium dioxide (TiCL) are rutile, anatase, and brookite. Brookite is orthorhombic, whereas rutile and anatase are tetragonal (PAflmnm and lAfamd space groups, respectively) (Klein, 2002, 383-384). Titanium dioxides may sorb both As(III) and As(V) from water. The compounds are also important photocatalysts in the oxidation of As(III), MMA(V), and DMA(V) to inorganic As(V) in water (Nakajima et al., 2005 Xu, Cai and O Shea, 2007). 

Titanium dioxide (Ti02, density 4.26) occurs in two crystalline forms, anatase and the more stable rutile. Anatase can be converted to rutile by heating to 700 to 950°C. It is variously colored, depending upon source, decomposes at about 1640°C before melting, and is insoluble in water but soluble in sulfuric acid or alkalis. 

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]. 

Ti02 is an important oxide with a broad range of applications in catalysis (as a catalyst or a support) (6), photocatalysis (35, 36), and sensor technology it is also used as a pigment. Of the three titanium dioxide polymorphs (rutile, anatase, and brookite), rutile and anatase have been most widely investigated they are the only ones reviewed here. 

Titanium dioxide (Ti02) is one of the most widely used semiconductors for heterogeneous photocatalysis. This is mainly due to its activity, photostabihty, non-toxicity and commercial availability. It is found in nature and can exist in three crystal modifications rutile, anatase and brookite (Kirk-Othmer, 1996). Its composition is temperature dependent at calcination temperatures above 900 K, the anatase modification is transformed into rutile. Ti02 is insoluble in water and in diluted acids, but it dissolves slowly in hot sulfuric acid (Remy, 1973). It has a high surface activity and corrosion stabihty. The commercial production of this white pigment has been known since the early 1900s. 

Titanium Oxide 6 Complex Oxides Sulfide. The naturally occurring dioxide Ti02 has three crystal modifications, rutile, anatase, and brookite. In rutile, the commonest, the Ti is octahedral and this structure is a common one for MX2 compounds. In anatase and brookite there are very distorted octahedra of oxygen atoms about each titanium, two being relatively close. Although rutile has been assumed to be the most stable form because of its common occurrence, anatase is 8 to 12 kJ mol-1 more stable than rutile. 

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]. 

Titania (Ti02) occurs in nature in three crystal modifications as anatase, rutile and brookite. Rutile is the most common form which has octahedral coordination of titanium ions. Anatase and brookite contain distorted octahedra. Anatase is thermodynamically 8 to 12 kJ/mol more stable than rutile (1). Brookite on the other hand is thermodynamically unstable. 

Three polymorphs of titanium dioxide occur naturally, namely rutile, anatase and brookite, but surface scientists have concentrated almost entirely on the... 

An increasing interest in studying silver particles and clusters adsorbed on titanium dioxide surface is provided by the efficiency of such systems as photocatalysts. Their catalytic properties are more evident than those of individual Ti02, both anatase and rutile-anatase mixture. There are few publications devoted to quantum chemical calculations of metal clusters adsorbed on TiOz surface at the modem level of theory. Besides, existing theoretical data describe adsorption of silver atom on mtile surface only. 

Titanium dioxide may occur in several different crystalline forms rutile anatase and brookite. Of these, rutile and anatase are the only forms of commercial importance. Rutile is the more thermodynamically stable and is used more frequently than the other crystalline forms. 

Let us finally turn to a brief discussion of the third term, Ti02 (i.e., titanium dioxide). Ti02 has three different crystal structures [18] rutile, anatase, and brookite only the former two of them are commonly used in photocatalysis. Like for many other metal oxides (also for titanium oxide) have the respective structural, optical, and electronic properties... 

Bourikas, K., Hiemstra, T., and van Riemsdijk, W.H., Ion pair formation and primary charging behavior of titanium oxide (anatase and rutile), Langmuir, 17, 749, 2001. 

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... 

Titanium dioxide exists in nature in three crystalline forms rutile, anatase and brookite. Brookite is an alkali stabilized modification and has never been observed in evaporated films but was found in dip-coated ones. In the case of reactive evaporation of TiO (vapour phase Ti + TiO) and condensation of the vapour on hot substrates (glass, or SiO and C films) depending on the temperature of the substrate Ts, various 2 phases are obtained ... 

Titanium (IV) oxide crystallizes In three modifications of decreasing stability rutile, anatase and brookite. Whether the synthesis of brookite has been achieved is still in doubt. Anatase is formed via the hydrolysis of Ti halides at not too high a temperature (600°C) or via low-temperature calcining ( 700°C) of precipitated titanic acid. The lattice is stabilized by adsorbed anions, among which the most effective are sulfate and phosphate. Pure TiOg calcined at high temperature always yields the rutile lattice. 

Titanium Dioxide. - The extensive literature on the surface properties of Ti02 (rutile, anatase) was reviewed in 1976 by Parfitt. Since then, papers on the subject using conventional spectroscopies have been published mainly by Rochester and co-workers (rutile), Munuera, and our group (anatase). 

Titanium dioxide. Cl 77891, also known as titanium (IV) oxide, CAS No. 13463-67-7 with molecular weight of 79.87 is the naturally occurring oxide of titanium. When used as a pigment, it is called Titanium White and Pigment White 6 . Titanium dioxide is extracted from a variety of naturally occurring ores that contain ilmenite, rutile, anatase and leucoxene. 

Titanium dioxide is the most stable oxide of titanium, and can be obtained from either natural or synthetic sources. The material exists naturally in three crystal modifications, known as rutile, anatase, and brookite [1]. 

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