Titanium (III) chloride

Crystal structure
__ Ti 3+      __ Cl -
General
Surname	Titanium (III) chloride
other names	Titanium trichloride
Ratio formula	TiCl 3
Brief description	self-igniting, violet crystals
External identifiers / databases
CAS number 7705-07-9 EC number 231-728-9 ECHA InfoCard 100,028,845 PubChem 62646 Wikidata Q417420
properties
Molar mass	154.26 g mol −1
Physical state	firmly
density	2.6 g cm −3
Melting point	440 ° C (decomposition)
solubility	decomposes in water with violent reaction
safety instructions
GHS labeling of hazardous substances danger H and P phrases H: 250-290-314 EUH: 014 P: 303 + 361 + 353-305 + 351 + 338-310-405-422-501
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Titanium (III) chloride is an oxygen-sensitive chemical compound from the group of chlorides .

Extraction and presentation

Titanium (III) chloride is formed when titanium (IV) chloride is reduced with titanium or antimony, for example, and when titanium reacts with hot hydrochloric acid .

${\displaystyle \mathrm {3\ TiCl_{4}+Ti\longrightarrow 4\ TiCl_{3}} }$

${\displaystyle \mathrm {3\ TiCl_{4}+Sb\longrightarrow 3\ TiCl_{3}+SbCl_{3}} }$

To produce α-titanium trichloride, titanium tetrachloride vapor is fed together with a lot of hydrogen into a tube heated to 500 ° C, which forms a violet powder.

In inert , organic media, titanium tetrachloride forms brown, crystalline β-titanium trichloride with aluminum alkyls .

properties

Titanium (III) chloride solution

Titanium (III) chloride occurs in four different crystal structures .

α-titanium trichloride is bismuth triiodide - layer structure before. At temperatures above 475 ° C, it disproportionates into titanium tetrachloride and titanium dichloride .

β-titanium trichloride is Zirconiumtriiodid structure before. Without solvents, it converts to α-titanium trichloride at over 250–300 ° C, in inert solvents at 40–80 ° C.

Like all titanium trihalides except titanium trifluoride , titanium trichloride has only a slight paramagnetism due to the antiferromagnetic titanium-titanium interactions . The Néel temperature is 180 ° C.

With water in the absence of oxygen, unstable hydrates are formed , the green tetrahydrate ([Ti (H ₂ O) ₄ Cl ₂ ] Cl) or the violet hexahydrate ([Ti (H ₂ O) ₆ ] Cl ₃ ).

The standard enthalpy of formation is −721 kJ / mol, the Gibbs energy is −654 kJ / mol, the standard entropy 140 J / (mol K) and the heat capacity 97 J / (mol K). ${\displaystyle \Delta _{f}H_{s}^{0}}$ ${\displaystyle \Delta _{f}G_{s}^{0}}$ ${\displaystyle S_{s}^{0}}$ ${\displaystyle C_{p,s}^{0}}$

use

Titanium (III) chloride is used as a versatile reducing agent , Ziegler-Natta catalyst and as an additive in bleaching agents for textiles.

In titanometry , titanium trichloride solutions are used as powerful reducing agents for the determination of iron (III) ions, chromates , chlorates and perchlorates .

Titanium trichloride is used in test tubes to detect oxygen.

safety instructions

Titanium (III) chloride is self-igniting and has a corrosive effect. It reacts violently with oxidizing agents and on contact with water.

literature

• AF Holleman , E. Wiberg , N. Wiberg : Textbook of Inorganic Chemistry . 101st edition. Walter de Gruyter, Berlin 1995, ISBN 3-11-012641-9 .
• Collective of authors: Inorganikum . 5th edition. VEB Deutscher Verlag der Wissenschaften Berlin 1973.
• Entry on titanium chloride. In: Römpp Online . Georg Thieme Verlag, accessed on September 29, 2014.

Individual evidence

1. ↑ ^{a b c d e f} Entry on titanium (III) chloride in the GESTIS substance database of the IFA , accessed on January 8, 2018(JavaScript required) .
2. ↑ Georg Brauer (Ed.), With the collaboration of Marianne Baudler a . a .: Handbook of Preparative Inorganic Chemistry. 3rd, revised edition. Volume II, Ferdinand Enke, Stuttgart 1978, ISBN 3-432-87813-3 , p. 1341.
3. ^ GH Aylward, TJV Findlay: data collection chemistry in SI units . 3. Edition. Wiley-VCH, 1999, ISBN 3-527-29468-6 .