Thorium(IV) chloride

Last updated
Thorium(IV) chloride
Kristallstruktur Uran(IV)-chlorid.png
Identifiers
3D model (JSmol)
ECHA InfoCard 100.030.039
PubChem CID
UNII
Properties
ThCl4
Molar mass 373.849 g/mol
Appearancewhite needles
hygroscopic
Density 4.59 g/cm3, solid
Melting point 770 °C (1,420 °F; 1,040 K)
Boiling point 921 °C (1,690 °F; 1,194 K)
Structure
tetragonal
Hazards
not listed
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
X mark.svgN  verify  (what is  Yes check.svgYX mark.svgN ?)
Infobox references

Thorium(IV) chloride (Th Cl4) is an inorganic chemical compound. In addition to the anhydrous ThCl4, two hydrates have been reported: ThCl4(H2O)4 [1] and ThCl4(H2O)8. [2] These hygroscopic salts are water-soluble and white, at room temperature. Similar to other thorium complexes thorium(IV) chloride has a high melting point 770 °C (1,418 °F) and a boiling point of 921 °C (1,690 °F). Like all the other actinides, thorium is radioactive and has sometimes been used in the production of nuclear energy. Thorium(IV) chloride does not appear naturally but instead is derived from Thorite, Thorianite, or Monazite which are naturally occurring formations.

Thorium Chemical element with atomic number 90

Thorium is a weakly radioactive metallic chemical element with the symbol Th and atomic number 90. Thorium is silvery and tarnishes black when it is exposed to air, forming thorium dioxide; it is moderately hard, malleable, and has a high melting point. Thorium is an electropositive actinide whose chemistry is dominated by the +4 oxidation state; it is quite reactive and can ignite in air when finely divided.

Chlorine Chemical element with atomic number 17

Chlorine is a chemical element with the symbol Cl and atomic number 17. The second-lightest of the halogens, it appears between fluorine and bromine in the periodic table and its properties are mostly intermediate between them. Chlorine is a yellow-green gas at room temperature. It is an extremely reactive element and a strong oxidising agent: among the elements, it has the highest electron affinity and the third-highest electronegativity on the Pauling scale, behind only oxygen and fluorine.

Chemical compound Substance composed of multiple elements

A chemical compound is a chemical substance composed of many identical molecules composed of atoms from more than one element held together by chemical bonds. Two atoms of the same element bonded in a molecule do not form a chemical compound, since this would require two different elements.

Contents

History

Thorium was first discovered by Jons Jacob Berzelius in 1828. After receiving a sample of minerals from his colleague Jens Esmarck, Berzelius was able to isolate thorium using a method that had been used for other metals like cerium, zirconium, and titanium. This process involved using alkali metals to disassociate the thorium from its prior ligand form ThSiO4 (further described in synthesis). An intermediate in the isolation process was thorium(IV) chloride and thus the compound was discovered. [3]

Jöns Jacob Berzelius Swedish chemist

Baron Jöns Jacob Berzelius, known throughout his life as Jacob Berzelius, was a Swedish chemist. Berzelius is considered, along with Robert Boyle, John Dalton, and Antoine Lavoisier, to be one of the founders of modern chemistry.

Jens Esmark Danish-Norwegian professor of mineralogy

Jens Esmark was a Danish-Norwegian professor of mineralogy who contributed to many of the initial discoveries and conceptual analyses of glaciers, specifically the concept that glaciers had covered larger areas in the past.

Structures

The structure of thorium(IV) chloride is square planar with a symmetry of D4h. In this coordinate compound the bond length between the Th-Cl bond is 2.690 Å. The structure has been reported as hydrous or anhydrous. Due to the compound’s hydroscopic nature in the presence of water it can form either ThCl4(H2O)4 and ThCl4(H2O)8. [4]

Synthesis

Thorium(IV) Chloride can be produced in a variety of ways but the most common starting reactant is either thorium dioxide or Thorium (IV) orthosilicate.

Thorium dioxide Chemical compound

Thorium dioxide (ThO2), also called thorium(IV) oxide, is a crystalline solid, often white or yellow in color. Also known as thoria, it is produced mainly as a by-product of lanthanide and uranium production. Thorianite is the name of the mineralogical form of thorium dioxide. It is moderately rare and crystallizes in an isometric system. The melting point of thorium oxide is 3300 °C – the highest of all known oxides. Only a few elements (including tungsten and carbon) and a few compounds (including tantalum carbide) have higher melting points. All thorium compounds are radioactive because there are no stable isotopes of thorium.

Thorium(IV) orthosilicate (ThSiO4) is an inorganic chemical compound.

One way thorium(IV) chloride is synthesized is through a carbothermic reaction. The carbothermic reaction require very high temperature ranging from 700 °C to 2600 °C. What necessitates these extreme environments are thorium dioxides melting temperature of 3,390 °C. [4] The reaction between graphite and thorium dioxide usually takes place in a stream of chlorine gas forming the thorium(IV) chloride. However the chlorination reaction can be done by another compound Cl2-CCl4 which is a more stable reactant than pure Chlorine gas. Cl2-CCl4 is formed by passing a gas mixture of Cl2 through a wash bottle filled with CCl4. [5] [6]

Carbothermic reactions involve the reduction of substances, often metal oxides, using carbon as the reducing agent. These chemical reactions are usually conducted at temperatures of several hundred degrees Celsius. Such processes are applied for production of the elemental forms of many elements. Carbothermic reactions are not useful for some metal oxides, such as those of sodium and potassium. The ability of metals to participate in carbothermic reactions can be predicted from Ellingham diagrams.

ThO2 + 2 C + 4 Cl2 → ThCl4 + 2 CO

Another less common method of synthesis relies on heating thorium metal with NH4Cl at 300 °C for 30 h making a (NH4)2ThCl6. This product is then heated at 350 °C under a high vacuum to produce ThCl4. [4]

Application

Thorium(IV) chloride is an intermediate in many different experiments. The first type of experiment is the purification of Thorium.

1. Reduction of ThCl4 with alkali metals.

2. Electrolysis of anhydrous thorium(IV) chloride in fused mixture of NaCl and KCl.

3. Ca reduction of Thorium(IV) Chloride mixed with anhydrous zinc chloride. [7]

The process of producing pure thorium is normally for its production as the initial stage of producing a nuclear fuel. Thorium is sometimes mistaken for a nuclear fuel like uranium however it is not and requires neutron bombardment or other modifications to be applicable in the nuclear fuel cycle. [5]

The other application of thorium(IV) chloride is a perquisite for other thorium complexes. In these reactions Thorium (IV) Chloride is the initial reagent but it is first changed into ThCl4(DME)2. ThCl4(DME)2 is a versatile reagent that can be converted into ThCl4(TMEDA)2, ThBr4(DME)2.and others. [4]

Related Research Articles

Lanthanum Chemical element with atomic number 57

Lanthanum is a chemical element with the symbol La and atomic number 57. It is a soft, ductile, silvery-white metal that tarnishes slowly when exposed to air and is soft enough to be cut with a knife. It is the eponym of the lanthanide series, a group of 15 similar elements between lanthanum and lutetium in the periodic table, of which lanthanum is the first and the prototype. It is also sometimes considered the first element of the 6th-period transition metals, which would put it in group 3, although lutetium is sometimes placed in this position instead. Lanthanum is traditionally counted among the rare earth elements. The usual oxidation state is +3. Lanthanum has no biological role in humans but is essential to some bacteria. It is not particularly toxic to humans but does show some antimicrobial activity.

Zirconium Chemical element with atomic number 40

Zirconium is a chemical element with the symbol Zr and atomic number 40. The name zirconium is taken from the name of the mineral zircon, the most important source of zirconium. It is a lustrous, grey-white, strong transition metal that closely resembles hafnium and, to a lesser extent, titanium. Zirconium is mainly used as a refractory and opacifier, although small amounts are used as an alloying agent for its strong resistance to corrosion. Zirconium forms a variety of inorganic and organometallic compounds such as zirconium dioxide and zirconocene dichloride, respectively. Five isotopes occur naturally, three of which are stable. Zirconium compounds have no known biological role.

Group 4 element group of chemical elements

Group 4 is a group of elements in the periodic table. It contains the elements titanium (Ti), zirconium (Zr), hafnium (Hf) and rutherfordium (Rf). This group lies in the d-block of the periodic table. The group itself has not acquired a trivial name; it belongs to the broader grouping of the transition metals.

Titanium tetrachloride inorganic chemical compound

Titanium tetrachloride is the inorganic compound with the formula TiCl4. It is an important intermediate in the production of titanium metal and the pigment titanium dioxide. TiCl4 is a volatile liquid. Upon contact with humid air, it forms spectacular opaque clouds of titanium dioxide (TiO2) and hydrated hydrogen chloride. It is sometimes referred to as "tickle" or "tickle 4" due to the phonetic resemblance of its molecular formula (TiCl4) to the word.

Cerium(III) chloride chemical compound

Cerium(III) chloride (CeCl3), also known as cerous chloride or cerium trichloride, is a compound of cerium and chlorine. It is a white hygroscopic solid; it rapidly absorbs water on exposure to moist air to form a hydrate, which appears to be of variable composition, though the heptahydrate CeCl3·7H2O is known. It is highly soluble in water, and (when anhydrous) it is soluble in ethanol and acetone.

Tin(IV) chloride, also known as tin tetrachloride or stannic chloride, is an inorganic compound with the formula SnCl4. It is a colourless hygroscopic liquid, which fumes on contact with air. It is used as a precursor to other tin compounds. It was first discovered by Andreas Libavius (1550–1616) and was known as spiritus fumans libavii.

Chromium(III) chloride chemical compound

Chromium(III) chloride (also called chromic chloride) describes any of several compounds of with the formula CrCl3 • xH2O, where x can be 0, 5, and 6. The anhydrous compound with the formula CrCl3 is a violet solid. The most common form of the trichloride is the dark green hexahydrate, CrCl3 • 6H2O. Chromium chlorides find use as catalysts and as precursors to dyes for wool.

Nickel(II) chloride chemical compound

Nickel(II) chloride (or just nickel chloride), is the chemical compound NiCl2. The anhydrous salt is yellow, but the more familiar hydrate NiCl2·6H2O is green. Nickel(II) chloride, in various forms, is the most important source of nickel for chemical synthesis. The nickel chlorides are deliquescent, absorbing moisture from the air to form a solution. Nickel salts have been shown to be carcinogenic to the lungs and nasal passages in cases of long-term inhalation exposure.

Hafnium tetrachloride chemical compound

Hafnium(IV) chloride is the inorganic compound with the formula HfCl4. This colourless solid is the precursor to most hafnium organometallic compounds. It has a variety of highly specialized applications, mainly in materials science and as a catalyst.

Zirconium(IV) chloride chemical compound

Zirconium(IV) chloride, also known as zirconium tetrachloride, (ZrCl4) is an inorganic compound frequently used as a precursor to other compounds of zirconium. This white high-melting solid hydrolyzes rapidly in humid air.

Zirconium(IV) bromide is the inorganic compound with the formula ZrBr4. This colourless solid is the principal precursor to other Zr–Br compounds.

Yttrium(III) chloride chemical compound

Yttrium(III) chloride is an inorganic compound of yttrium and chloride. It exists in two forms, the hydrate (YCl3(H2O)6) and an anhydrous form (YCl3). Both are colourless solids that are highly soluble in water and deliquescent.

Organoactinide chemistry any organometallic compound having a bond between a carbon and an actinide

Organoactinide chemistry is the science exploring the properties, structure and reactivity of organoactinide compounds, which are organometallic compounds containing a carbon to actinide chemical bond.

The chloride process is used to separate titanium from its ores. In this process, the feedstock is treated at 1000 °C with carbon and chlorine gas, giving titanium tetrachloride. Typical is the conversion starting from the ore ilmenite:

Cerium Chemical element with atomic number 58

Cerium is a chemical element with the symbol Ce and atomic number 58. Cerium is a soft, ductile and silvery-white metal that tarnishes when exposed to air, and it is soft enough to be cut with a knife. Cerium is the second element in the lanthanide series, and while it often shows the +3 oxidation state characteristic of the series, it also exceptionally has a stable +4 state that does not oxidize water. It is also considered one of the rare-earth elements. Cerium has no biological role in humans and is not very toxic.

Titanium nitrate compound of titanium

Titanium nitrate is the inorganic compound with formula Ti(NO3)4. It is a colorless, diamagnetic solid that sublimes readily. It is an unusual example of a volatile binary transition metal nitrate. Ill defined species called titanium nitrate are produced upon dissolution of titanium or its oxides in nitric acid.

Titanium perchlorate chemical compound

Titanium perchlorate is a molecular compound of titanium and perchlorate groups with formula Ti(ClO4)4. Anhydrous titanium perchlorate decomposes explosively at 130°C and melts at 85°C with a slight decomposition. It can sublime in a vacuum as low as 70°C, and can form vapour at up to 120°. Titanium perchlorate is quite volatile. It has density 2.35. It decomposes to TiO2, ClO2 and dioxygen O2 Also TiO(ClO4)2 is formed during decomposition.

References

  1. Cantat, Thibault; Scott, Brian L.; Kiplinger, Jaqueline L. "Convenient Access to the Anhydrous Thorium Tetrachloride Complexes ThCl4(DME)2, ThCl4(1,4-dioxane)2 and ThCl4(THF)3.5 using Commercially Available and Inexpensive Starting Materials" Chemical Communications 2010, 46, 919-921. doi : 10.1039/b923558b
  2. P. Ehrlich "Titanium, Zirconium, Hafnium, and Thorium" in Handbook of Preparative Inorganic Chemistry, 2nd Ed. Edited by G. Brauer, Academic Press, 1963, NY. Vol. 1. p. 1203.
  3. Weeks, Mary Elvira (1932-07-01). "The discovery of the elements. XI. Some elements isolated with the aid of potassium and sodium: Zirconium, titanium, cerium, and thorium". Journal of Chemical Education. 9 (7): 1231. doi:10.1021/ed009p1231. ISSN   0021-9584.
  4. 1 2 3 4 Cantat, Thibault; Scott, Brian L.; Kiplinger, Jaqueline L. (2010-01-25). "Convenient access to the anhydrous thorium tetrachloride complexes ThCl4(DME)2, ThCl4(1,4-dioxane)2 and ThCl4(THF)3.5 using commercially available and inexpensive starting materials" (PDF). Chemical Communications. 46 (6): 919. doi:10.1039/b923558b. ISSN   1364-548X. PMID   20107650.
  5. 1 2 Brauer, Georg (1963). Handbook Of Preparative Inorganic Chemistry. New York: Academic Press.
  6. Gutierrez, R.L.; Herbst, R.J. (October 1979). "Preliminary Fabrication Studies of Alternative LMFBR Carbide Fuels". Los Alamos Scientific Laboratory.
  7. "Periodic Table of Elements: Los Alamos National Laboratory". periodic.lanl.gov. Retrieved 2016-04-29.