Determination of purity of fluoromethanes for industrial use. Gas chromatography (1)

1 Scope

This standard specifies the test methods for the component analysis of industrial fluoromethane monofluorotrichloromethane (CFC-11) difluorodichloromethane (CFC-12) and difluoromonochloromethane (HCFC-22)

This standard is applicable to industrial fluoromethane fluorotrichloromethane (CFC-11), difluorodichloromethane (CFC-12) and difluoromonochloromethane (HCFC-22) for industrial use with a mass fraction of not less than 99.

2 Normative references

The clauses in the following documents have become clauses of this standard after being quoted in this standard

GB/T97221988 Chemical Reagent Gas Chromatography General Rules

3 Method summary

Under the conditions specified in this standard, the gas or liquid of the fluoromethane sample is vaporized and passed through the chromatographic column to separate the components to be measured, detected by a hydrogen flame detector, and calculated by the area calibration normalization method The quality score

4 Reagents and materials

4.

4.

4.

5 Instruments

5.

5.

5.

5.

5.

5.

5.

5.

5.

6 Chromatographic analysis conditions

6.
1 Capillary column chromatography

6.
1.
1 Recommended chromatographic capillary column and operating conditions are shown in Table 1, a typical chromatogram fluorinated methanes and relative retention times of Appendix A
.

Other capillary columns and chromatographic operating conditions that can achieve the same degree of separation can be used
.

Table 1 Recommended capillary column and chromatographic operating conditions

6.
2 Packed column chromatography

6.
2.
1 The recommended packed column and chromatographic operating conditions are shown in Table 2
.
The typical chromatograms and relative retention times of fluoromethanes are shown in Appendix A.
Other packed columns and chromatographic operating conditions that can achieve the same degree of separation can be used
.

Table 2 Recommended packed column and chromatographic operating conditions

Related Links: Determination of Trace Amines in Industrial Butadiene (2)