Reaction with bromine III fluoride

COFj is formed, in conjunction with COBrF, when carbon monoxide is bubbled through bromine(III) fluoride at 8-30 C, according to [1196a,1596]  

The reaction is rapid and exothermic (and may be explosive at too high a temperature), and the COFj and COBrF are readily separated by condensing out the COBrF into a trap cooled to -78 C, and subsequently trapping the COFj into a trap cooled to -196 C. To remove the final traces of bromine from the COFj, it may be passed over antimony powder and recondensed [1193], 

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