Deep Oxidation of Fluorinated Hydrocarbons in Molten Catalysts

Yu.S. Chekryshkin1, T.A. Rozdyalovskaya1, Z.R. Ismagilov2, M.A. Kerzhentsev2, O.A. Tetenova1 and A.A. Fedorov1

1Institute of Technological Chemistry, 13a, Lenin str., 614600 Perm’, Russia

2Boreskov Institute of Catalysis, Prosp. Akad. Lavrentieva, 5, 630090, Novosibirsk, Russia e-mail zri@catalysis.nsk.su

Abstract

The oxidation of fluorine-containing organic substances: fluorocarbon liquid M-1, fluorinated alcohol H(CF2)8CH2OH, and powder polytetrafluoroethylene with air has been studied in melts: NaOH; 43 mol.% LiCl – 33 mol.% NaCl – 24 mol.% KCl (eutectic mixture); (LiCl-NaCl-KCl)eutec. + 10 mass.% V2O5; (LiCl-NaCl-KCl) eutec. + 15 mass.% V2O5; 56 mol.% Na2CO3 – 44 mol.% K2CO3 (eutectic), (Na2CO3 –K2CO3)eutect. + 15 mass.% V2O5, and K3V5O14.

The compositions of the melts have been examined by GC, DTA, chemical analysis and XRD, and they have been shown to change during the reaction, depending on the composition and partial pressure of the gaseous products over the melt surface. The alkali metal chloride melt containing 15 mass.% V2O5 has been found to be most stable to the action of fluorine compounds.

Possibility of deep oxidation of fluorine-containing organic substances in melts based on hydroxides, carbonates and chlorides of alkali metals doped with oxides of vanadium has been proved. The process of deep oxidation of fluorinated hydrocarbons is accompanied by formation of an equilibrium mixture containing hydroxides, carbonates, chlorides and fluorides of alkali metals, as well as their vanadates, if V2O5 additive is used. The relative amounts of these substances in molten systems are determined by the partial pressure of oxygen, CO2 and water vapor.