Chemical Properties
Zirconium tetrachloride forms lustrous, white, monoclinic
crystals that melt at 437 ℃. It is a corrosive powder. It is
hygroscopic, and thus soluble in cold water, alcohol, ether,
and concentrated hydrochloric acid. It reacts vigorously with
water forming hydrogen chloride (irritating vapor) and zirconium
oxychloride. When moist, zirconium tetrachloride
reacts with common materials to form hydrochloric acid that
is corrosive to many metals. Through hydrolysis to HCl,
zirconium tetrachloride can irritate the respiratory tract and
other superficial surfaces of the body on exposure.
Zirconium tetrachloride readily forms coordinate bonds with
oxygen and nitrogen in organic molecules.
Physical properties
White monoclinic crystals; hygroscopic; density 2.80 g/cm
3; sublimes at 331°C; triple point 437°C; vapor pressure 1 torr at 190°C; critical temperature 504.85°C; critical pressure 56.95 atm; critical volume 319 cm3/mol; decomposed by water; soluble in alcohol, ether, and concentrated hydrochloric acid.
Uses
Zirconium tetrachloride is commonly utilized as a Lewis acid catalyst in many organic synthesis reactions. It is an important source for organometallic complexes of zirconium. It is practiced in many areas like nuclear industry, metal industry, photography, glass, and ceramic industry.
Uses
Friedel-Crafts catalyst. Component of Ziegler-type catalysts in the condensation of ethylene. Starting material in the synthesis of a number of organic derivatives of zirconium, such as alkoxides and zircocene. The alkoxides have been shown to be of value in the curing of silicone plastic films. The alkoxyzirconium carboxylates are said to be useful in the water-repellent treatment of textiles and other fibrous materials.
Uses
Zirconium(IV) chloride (ZrCl4) is a Lewis acid catalyst, which has low toxicity. It is a moisture resistant material that is used as a catalyst in organic transformations.
ZrCl4 can be used as a catalyst for a variety of organic syntheses, such as Friedel-Crafts reaction, condensation reaction and other reduction reactions.
Uses
For applications in organozirconium chemistry.
1. Activates pyrrolidines for improved conversion, via a modified Bouveault reaction, to the corresponding α,α-dimethylamines.
2. Zirconium (IV) chloride is used as an efficient catalyst in the Pechmann condensation reaction of phenols with β‐keto esters leading to the formation of coumarin derivatives in good yields under solvent‐free conditions.
Preparation
Zirconium tetrachloride is obtained as an intermediate in recovering zirconium metal from zircon and other minerals (See Zirconium, Recovery). The tetrachloride is obtained by heating a mixture of zirconium hydroxide and car 1004 bon with chlorine gas
Also, tetrachloride can be made by reacting zirconium hydroxide with hydrochloric acid: Zr(OH)
4 + 4HCl → ZrCl
4 + 4H
2O.
Definition
ChEBI: Zirconium tetrachloride is a zirconium coordination entity comprising four chlorine atoms bound to a central zirconium atom. It has a role as a catalyst. It is a zirconium coordination entity and an inorganic chloride.
General Description
White lustrous crystalline solid. Used as a source of pure zirconium, as a tanning agent, in analytical chemistry and in treating textiles. Zirconium tetrachloride is decomposed by water. Corrosive to metals in the presence of moisture and to tissue.
Air & Water Reactions
Reacts vigorously with water forming hydrochloric acid with the evolution of heat.
Reactivity Profile
Zirconium tetrachloride is corrosive to metals in the presence of moisture and to tissue. Behavior in Fire: Will not burn - sublimes above 626°F (331°C). May give off HCl fumes [USCG, 1999]. Zirconium tetrachloride is incompatible with alcohols (ethanol), lithium metal, and tetrahydrofuran.
Health Hazard
INHALATION: Irritating to upper respiratory tract; presumably caused by liberated HCl. EYES: Irritating. SKIN: Irritating. INGESTION: Burning pain in the mouth and throat, vomiting, watery or bloody diarrhea, retching, collapse, and convulsions.
Fire Hazard
Behavior in Fire: Will not burn - sublimes above 626°F (331°C). May give off HCl fumes.
Flammability and Explosibility
Non flammable
reaction suitability
reagent type: catalyst
core: zirconium
Safety Profile
Moderately toxic by
ingestion. A corrosive irritant to skin, eyes,
and mucous membranes. Ignites
spontaneously in air. When heated to
decomposition it emits toxic fumes of Cl-.
See also ZIRCONIUM COMPOUNDS and
HYDROCHLORIC ACID.
Synthesis
Zirconium tetrachloride can be synthesized from the direct reaction between Zr metal and Cl2 gas at high temperatures (>350°C), or from the treatment of ZrO2 with CCl4 or Cl2 gas in the presence of carbon.
Purification Methods
Crystallise it repeatedly from conc HCl. It is hydrolysed by H2O to form white ZrOCl2 (see below) and HCl. [Krebs Z Anorg Allgem Chem 378 263 1970.]
References
[1] ROSENDO BORJAS NEVAREZ. Zirconium tetrachloride revisited.[J]. Acta Crystallographica Section C Structural Chemistry, 2018, 74 Pt 3: 307-311. DOI:
10.1107/S205322961800219X.
[2] SCOTT P. Alkylation of zirconium tetrachloride with benzyl Grignard[C]. 2001: 0. DOI:10.1039/SP1.
[3] S. E. KRAVCHENKO. Formation of zirconium diboride nanoparticles as a result of reaction between zirconium tetrachloride and sodium borohydride[J]. Inorganic Materials, 2017, 53 8: 804-808. DOI:
10.1134/S002016851708009X.
[4] XIN TONG. Achieving low-temperature Zr alloying for microstructural refinement of sand-cast Mg-Gd-Y alloy by employing zirconium tetrachloride[J]. Materials Characterization, 2021, 171: Article 110727. DOI:
10.1016/j.matchar.2020.110727.
