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User:JWB/Chloride volatility

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Chloride volatility is a method for the removal of elements, which form volatile chlorides, from fused molten chloride salts. Its principle of operation is the chemical oxidation of the elements in the spent fuel by atomic chlorine, which then escapes. It is being studied for reprocessing of nuclear fuel.

Some work has been undertaken on a closely related subject in the Czech Republic at Řež,[1] there an experimental rig exists in which simulated spent fuel is treated with chlorine gas diluted in nitrogen gas]] to form uranium hexachloride [2]. The uranium hexachloride is then distilled to remove other volatile metal chlorides and iodine chloride [3] [4]. The involatile mixture of fission products and minor actinides formed by the reaction of the chlorine gas with the uranium oxide is most suitable for further processing with 'dry' electrochemical processing (pyrochemical) nuclear reprocessing. The involitile lanthanide chlorides would be difficult to dissolve in the nitric acid used for aqueous reprocessing methods, such as SANEX, DIAMEX and SANEX, which use solvent extraction. chloride volatility is only one of several pyrochemical processes designed to reprocess used nuclear fuel.

Many pentachlorides and monochlorides have boiling and melting points similar to those of the corresponding fluorides, while many tetrachlorides, trichlorides and dichlorides have significantly lower boiling and melting temperatures than those of the corresponding fluorides.

chlorides by boiling and melting points

[edit]
chloride Z Boiling point Melting point Key halflife Yield
Hexachlorides, heptachlorides - not converted
SeCl6 34 -46.6ºC -50.8ºC 79Se:65ky .04%
TeCl6 52 -39°C -38°C 127mTe:109d
ICl7 53 4.8°C (1 atm) 6.5°C (tripoint) 129I:15.7my 0.54%
MoCl6 42 34°C 17.4°C 99Mo:2.75d
PuCl6 94 52°C (subl) 62°C 239Pu:24ky
TcCl6 43 55.3°C 37.4°C 99Tc:213ky 6.1%
UCl6 92 56.5°C (subl) 64.8°C 233U:160ky
RuCl6 44 54°C 106Ru:374d
RhCl6 45 70°C 103Rh:stable
Pentachlorides, tetrachloride oxides
BrCl5 35 °C °C 81Br:stable
ICl5 53 °C °C 129I:15.7my 0.54%
SbCl5 51 140°C 4°C 125Sb:2.76y
RuOCl4 44 °C °C 106Ru:374d
RuCl5 44 °C °C 106Ru:374d
NbCl5 41 254°C 204.7°C 95Nb:35d low
MoCl5 42 268°C 194°C 99Mo:2.75d
Tetrachlorides, monochlorides
ICl 53 97.4°C 27°C 129I:15.7my 0.54%
SnCl4 50 114.1°C -33°C 121m1Sn:44y
126Sn230ky
0.013%
?
PdCl4 46 107Pd:6.5my
ZrCl4 40 331°C (subl) 93Zr:1.5my 6.35%
UCl4 92 791°C 590°C 233U:160ky
ThCl4 90 921°C 770°C
AgCl 47 °C °C 109Ag:stable
CsCl 55 1295°C 645°C 137Cs:30.2y
135Cs:2.3my
6.19%
6.54%
RbCl 37 1390 °C 718°C 87Rb:49by
ClLiNaK °C °C stable
LiCl 3 >1300°C 605°C stable
NaCl 11 1465 °C 801 °C stable
Trichlorides, dichlorides
CdCl2 48 960°C 564°C 113mCd:14.1y
InCl3 49 586°C 115In:441ty
SrCl2 38 1250°C 874°C 90Sr: 29.1y 5.8%
BaCl2 56 1560°C 962°C 140Ba:12.75d
YCl3 39 1507°C 721°C 91Y:58.51d
DyCl3 60 1530°C 647°C stable
GdCl3 60 1580°C 609°C stable
NdCl3 60 1600°C 758°C 147Nd:11d
PrCl3 58 1710°C 786°C stable
CeCl3 58 1730°C 817°C 144Ce:285d
SmCl3 62 decomp 682°C 151Sm:90y
146Sm:108y
0.419%
?

Missing: Pd 46, La 57, Pr 59, Pm 61, Eu 63 and up Inert: Kr 36, Xe 54


See also

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