Re: Chemical synthesis of F2

According to the book "Chemistry of the Elements" by Earnshaw and
Greenwood, the synthesis is done as follows:

Prepare K2MnF6, using HF only (no F2 needed to synthesize this
compound). In HF, this manganese (IV) complex is stable. Also prepare
SbF5, also in HF. The book does not state which antimony compound is
used as a starting point, but I can imagine that an SbF6(-) compound or
possibly SbCl5 or Sb2O5 can be used. For manganese I can imagine that
MnO2 or KMnO4 can be used, but the book does not mention it.

When these are brough together, then the following reaction occurs:

K2MnF6 + 2SbF5 ---> 2KSbF6 + MnF4

Manganese (IV) fluoride is not stable and decomposes to manganese (III)
fluoride and fluorine gas.

Christe did this experiment in a passivated Teflon-stainless steel
reactor at 150 C for 1 hour. He had a yield of 40% from the theoretical
equations, shown above.

All this information can be found at page 821 of the book I mentioned.

Hope this helps,

Wilco

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