Germanium tetrachloride is a colourless, fuming liquid[4] with a peculiar, acidic odour. It is used as an intermediate in the production of purified germanium metal. In recent years, GeCl4 usage has increased substantially due to its use as a reagent for fiber optic production.
Most commercial production of germanium is from treating flue-dusts of zinc- and copper-ore smelters, although a significant source is also found in the ash from the combustion of certain types of coal called vitrain. Germanium tetrachloride is an intermediate for the purification of germanium metal or its oxide, GeO2.[5]
Germanium tetrachloride can be generated directly from GeO2 (germanium dioxide) by dissolution of the oxide in concentrated hydrochloric acid. The resulting mixture is fractionally distilled to purify and separate the germanium tetrachloride from other products and impurities.[6] The GeCl4 can be rehydrolysed with deionized water to produce pure GeO2, which is then reduced under hydrogen to produce germanium metal.[5][6]
Production of GeO2, however, is dependent on the oxidized form of germanium extracted from the ore. Copper-lead-sulfide and zinc-sulfide ores will produce GeS2, which is subsequently oxidized to GeO2 with an oxidizer such as sodium chlorate. Zinc-ores are roasted and sintered and can produce the GeO2 directly. The oxide is then processed as discussed above.[5]
The classic synthesis from chlorine and germanium metal at elevated temperatures is also possible.[7][1] Additionally, a chlorine free activation of germanium has been developed, giving a less energy intensive and more environmentally friendly alternative synthesis for germanium precursors.
Applicationedit
Germanium tetrachloride is used almost exclusively as an intermediate for several optical processes. GeCl4 can be directly hydrolysed to GeO2, an oxide glass with several unique properties and applications, described below and in linked articles:
Fiber opticsedit
A notable derivative of GeCl4 is germanium dioxide. In the manufacture of optical fibers, silicon tetrachloride, SiCl4, and germanium tetrachloride, GeCl4, are introduced with oxygen into a hollow glass preform, which is carefully heated to allow for oxidation of the reagents to their respective oxides and formation of a glass mixture. The GeO2 has a high index of refraction, so by varying the flow rate of germanium tetrachloride the overall index of refraction of the optical fiber can be specifically controlled. The GeO2 is about 4% by weight of the glass.[5]
Referencesedit
^ abP.W. Schenk (1963). "Germanium(IV) Chloride". In G. Brauer (ed.). Handbook of Preparative Inorganic Chemistry, 2nd Ed. Vol. 1. NY, NY: Academic Press. pp. 715–716.
^Merz, K.; Driess, M. (2002). "Germanium(IV) chloride at 193 K". Acta Crystallogr. C. 58 (Pt 7): i101–i102. doi:10.1107/S0108270102010351. PMID 12094027.
^CRC handbook of chemistry and physics : a ready-reference book of chemical and physical data. William M. Haynes, David R. Lide, Thomas J. Bruno (2016-2017, 97th ed.). Boca Raton, Florida. 2016. ISBN978-1-4987-5428-6. OCLC 930681942.{{cite book}}: CS1 maint: location missing publisher (link) CS1 maint: others (link)
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Germanium tetrachloride is a colourless fuming liquid 4 with a peculiar acidic odour It is used as an intermediate in the production of purified germanium metal In recent years GeCl4 usage has increased substantially due to its use as a reagent for fiber optic production Germanium tetrachloride Germanium tetrachloride structural formula Germanium tetrachloride space filling modelNamesIUPAC names Germanium tetrachlorideTetrachlorogermaneTetrachloridogermaniumOther names Germanium IV chlorideNeutral germanium chloride 1 4 IdentifiersCAS Number 10038 98 9 Y3D model JSmol Interactive imageChemSpider 59611 YECHA InfoCard 100 030 093PubChem CID 66226RTECS number LY5220000UNII YSV1R803C0 YCompTox Dashboard EPA DTXSID1044350InChI InChI 1S Cl4Ge c1 5 2 3 4 YKey IEXRMSFAVATTJX UHFFFAOYSA N YInChI 1S Cl4Ge c1 5 2 3 4Key IEXRMSFAVATTJX UHFFFAOYSA NSMILES Cl Ge Cl Cl ClPropertiesChemical formula GeCl4Molar mass 214 40 g molAppearance Colourless liquidDensity 1 879 g cm3 20 C 1 844 g cm3 30 C 1 Melting point 49 5 C 57 1 F 223 7 K Boiling point 86 5 C 187 7 F 359 6 K Solubility in water Soluble hydrolysesSolubility Soluble in ether benzene chloroform CCl4 Very soluble in HCl dilute H2SO4Magnetic susceptibility x 72 0 10 6 cm3 molRefractive index nD 1 464StructureMolecular shape tetrahedral 2 Thermochemistry 3 Std molarentropy S 298 245 6 J mol 1 K 1Std enthalpy offormation DfH 298 531 8 kJ mol 1Gibbs free energy DfG 462 7 kJ mol 1HazardsOccupational safety and health OHS OSH Main hazards Reacts slowly with water to form HCl and GeO2 corrosive lachrymatorNFPA 704 fire diamond 302WFlash point Non flammableSafety data sheet SDS External MSDS Related compoundsOther anions Germanium tetrafluorideGermanium tetrabromideGermanium tetraiodideOther cations Carbon tetrachlorideSilicon tetrachlorideTin IV chlorideLead IV chlorideExcept where otherwise noted data are given for materials in their standard state at 25 C 77 F 100 kPa Y verify what is Y N Infobox references Contents 1 Production 2 Application 2 1 Fiber optics 3 References 4 See alsoProduction editMost commercial production of germanium is from treating flue dusts of zinc and copper ore smelters although a significant source is also found in the ash from the combustion of certain types of coal called vitrain Germanium tetrachloride is an intermediate for the purification of germanium metal or its oxide GeO2 5 Germanium tetrachloride can be generated directly from GeO2 germanium dioxide by dissolution of the oxide in concentrated hydrochloric acid The resulting mixture is fractionally distilled to purify and separate the germanium tetrachloride from other products and impurities 6 The GeCl4 can be rehydrolysed with deionized water to produce pure GeO2 which is then reduced under hydrogen to produce germanium metal 5 6 Production of GeO2 however is dependent on the oxidized form of germanium extracted from the ore Copper lead sulfide and zinc sulfide ores will produce GeS2 which is subsequently oxidized to GeO2 with an oxidizer such as sodium chlorate Zinc ores are roasted and sintered and can produce the GeO2 directly The oxide is then processed as discussed above 5 The classic synthesis from chlorine and germanium metal at elevated temperatures is also possible 7 1 Additionally a chlorine free activation of germanium has been developed giving a less energy intensive and more environmentally friendly alternative synthesis for germanium precursors Application editGermanium tetrachloride is used almost exclusively as an intermediate for several optical processes GeCl4 can be directly hydrolysed to GeO2 an oxide glass with several unique properties and applications described below and in linked articles Fiber optics edit A notable derivative of GeCl4 is germanium dioxide In the manufacture of optical fibers silicon tetrachloride SiCl4 and germanium tetrachloride GeCl4 are introduced with oxygen into a hollow glass preform which is carefully heated to allow for oxidation of the reagents to their respective oxides and formation of a glass mixture The GeO2 has a high index of refraction so by varying the flow rate of germanium tetrachloride the overall index of refraction of the optical fiber can be specifically controlled The GeO2 is about 4 by weight of the glass 5 References edit a b P W Schenk 1963 Germanium IV Chloride In G Brauer ed Handbook of Preparative Inorganic Chemistry 2nd Ed Vol 1 NY NY Academic Press pp 715 716 Merz K Driess M 2002 Germanium IV chloride at 193 K Acta Crystallogr C 58 Pt 7 i101 i102 doi 10 1107 S0108270102010351 PMID 12094027 CRC handbook of chemistry and physics a ready reference book of chemical and physical data William M Haynes David R Lide Thomas J Bruno 2016 2017 97th ed Boca Raton Florida 2016 ISBN 978 1 4987 5428 6 OCLC 930681942 a href Template Cite book html title Template Cite book cite book a CS1 maint location missing publisher link CS1 maint others link Greenwood Norman N Earnshaw Alan 1997 Chemistry of the Elements 2nd ed Butterworth Heinemann p 377 ISBN 978 0 08 037941 8 a b c d Germanium Mineral Commodity Profile U S Geological Survey 2005 a b The Elements C R Hammond David R Lide ed CRC Handbook of Chemistry and Physics Edition 85 CRC Press Boca Raton Florida 2004 GeCl4 synthesis account e jimdo com Technische Universita Ilmenau Retrieved 2020 09 22 See also editGermanium Optical fiber Infrared Retrieved from https en wikipedia org w index php title Germanium tetrachloride amp oldid 1192199720, wikipedia, wiki, book, books, library,
