ANALYSIS OF CHLOROFLUOROCARBON REPLACEMENT COMPOUNDS BY CAPILLARY GAS-CHROMATOGRAPHY

Several thick film wall-coated open tubular and porous-layer open tubu lar (PLOT) type capillary columns have been investigated for the separ ation of wide boiling range (-57.8 to 61.2-degrees-C) of hydrofluoroca rbons (HFCs) and halocarbons. The aim is to select the best column in terms of resolution, analysis time and conditions suitable for use in conjunction with an automated air analysis method for these compounds which are intended as replacements for the ozone-depleting chlorofluor ocarbons. The problems associated with each column are reported with e mphasis on the catalytic activity of two types of alumina PLOT columns towards certain HFCs and halocarbons. Due to their inherent basicity, the alumina PLOT columns induce dehydrochlorination reactions in spit e of the additional deactivation of the alumina with KCl and Na2SO4.