Separation of Fluoride from Inorganic Compounds by Pyrolysis

Abstract

An effective pyrolytic method has been developed for the separation of micro and macro quantities of

Simultaneous determination of fluorine, chlorine and bromine in cement with ion chromatography after pyrolysis

“…Four kinds of metal oxides, such as tungsten oxide (WO 3 ) [12], uranium oxide [12], ferric oxide [9] or vanadium oxide (V 2 O 5 ) [11,14], have been employed as an accelerator to separate fluorine compounds from inorganic compound by pyrolysis. In this study, WO 3 and V 2 O 5 were tested for the accelerator.…”

“…Ion chromatography (IC) system with an anion exchange column has applied for the determination of F − and Cl − in raw materials and geological samples after distillation, fusion or pyrolysis [9][10][11][12]. The Ceramic Society of Japan has also proposed a method for determining Br in SiC powder with IC after pyrolysis [13].…”

Studies on U-Zr and U-Pu-Zr alloys for determination of Cl and F using pyrohydrolysis

“…The percentage recovery values were calculated considering the 100% recovery of F and Cl at optimized conditions. In case of samples, which do not release the halides easily pyrohydrolysis is carried out using an accelerator [29]. Since uranium is already present in the alloy matrix it serves the purpose of accelerators and hence external addition of extractant was not necessary.…”

Determination of Microgram Quantities of Fluoride in Metal Oxides.

“…In solutions of low pH, Historically, caustic has been used by others (3,4) to trap fluoride and other products separated by pyrohydrolysis. A solution 0.025N in sodium hydroxide was used as the pyrohydrolysis trap solution in this laboratory.…”

“…electrode. The pyrohydrolysis apparatus used is a modification of that (3) reported by Powell and Menis l and is described in the appendix. The reaction conditions were kept constant during all fluoride separations to ensure uniformity of operation.…”