Ethane, 1,2-dichloro-1,1,2,2-tetrafluoro-.
1,2-Dichlorotetrafluoroethane
[
76-14-2].
Packaging and storage
Preserve in tight cylinders, and avoid exposure to excessive heat.
Identification
The IR absorption spectrum of it, determined in a 10-cm cell with sodium chloride windows, at atmospheric pressure, exhibits maxima, among others, at the following wavelengths, in µm: 4.34 (s), 4.48 (m), 5.28 (m), 5.95 (m), 7.36 (s), 9.5 (vs), 10.9 (vs), 11.8 (vs), 13.6 (s), and 14.8 (s). The stronger maxima are best obtained at pressures less than 10 mm of mercury.
Chromatographic purity
In the chromatogram recorded for the
Assay, identify the peaks due to dichlorodifluoromethane and trichloromonofluoromethane from relative retention times observed on chromatographing the
Resolution preparation: the sum of these two peak areas is not greater than 0.2% of the total of all peak areas, and the sum of the areas of all peaks other than that for dichlorotetrafluoroethane is not greater than 0.4% of the total of all peak areas.
Inorganic chlorides
Place 5 mL of anhydrous methanol in a test tube, add 3 drops of a saturated solution of silver nitrate in anhydrous methanol, shake, and add 7 g of Dichlorotetrafluoroethane: no opalescence or turbidity is produced.
Assay
Assay preparation
Introduce the liquid phase of Dichlorotetrafluoroethane into an evacuated headspace vial.
Procedure
Inject the gas phase headspace Assay preparation into the chromatograph, record the chromatogram, and measure the peak areas. Calculate the percentage (a/a) of C2C12F4 in the portion of Dichlorotetrafluoroethane taken.