GAS CHROMATOGRAPHIC METHOD FOR DETERMINING FLUOROHYDROCARBONS Russian patent published in 2004 - IPC

FIELD: analytical methods.

SUBSTANCE: in a method of determining fluorohydrocarbons, in particular for assaying gases in 1,1,1,2,3,3,3-heptafluoropropane synthesis, gas chromatographic separation of fluorohydrocarbon mixture to be assayed is performed in gas carrier flow on column filled with sorbent: 2:1 vol/vol mixture of exhaustively hydroxylated Silochrome and diatomite carrier impregnated with tributyl phosphate used in amount of 23-27% on the weight of carrier. 1,1,1,2,3,3,3-Heptafluoropropane to be assayed contains, as impurities, perfluoroisobutylene, 1,1,1,2,2,3,3-heptafluoropropane, and other fluorohydrocarbons. Components of crude product are registered with the aid of heat conductance detector and impurities in finished product by flame ionization detector. Lower measurement limit for perfluoroisobutylene is 0.001 vol %.

EFFECT: increased determination selectivity over a wide concentration range, including perfluoroisobutylene being most toxic among other impurities.

4 cl, 1 dwg, 5 tbl