Industrial 1,1,1,2-Tetrafluoroethane (HFC-134a) (5)

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In the formula: A _air — the peak area of ​​air;

V _sir — The volume fraction of air in the standard gas, %

Take the arithmetic average of three f _ARF measurements as the measurement result

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Measure the ambient temperature of the sample cylinder to be analyzed to the nearest 0.

For small package products, roll the sample cylinder to be analyzed for 2 minutes, and then connect the outlet valve of the sample cylinder to the inlet of the injection valve of the chromatograph.

For large-package products, connect the vacuum-dried sampling cylinder to the outlet valve of the product packaging container, open the outlet valve of the product packaging container, and then open the inlet and outlet valves of the sampling cylinder.

Repeat the injection continuously, and repeat the measured air peak area, indicating that the system is exhausted

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In the formula: A—the peak area of ​​air;

f _{ARF —Response} factor of standard gas air

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Where: φ—volume fraction of non-condensable gas (room temperature), %;

P—The saturated vapor pressure of the sample to be analyzed at the sampling environment temperature T(C), kPa, this value is checked by Appendix C (standard appendix);

T—the ambient temperature of the sample to be analyzed at the time of sampling, ℃;

P ₂₅ - sample to be analyzed at the saturated vapor pressure at 25 ℃, kPa, the value is verified by the annex C
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Take the arithmetic mean of the continuous measurement results as the measurement result, and the relative deviation of the continuous measurement results shall not exceed 10%
.

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7 Chloride (CI) test

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1 Method summary

Under acidic conditions, the chloride in the 1,1,1,2-tetrafluoroethane sample reacted with a saturated silver nitrate solution to form a silver chloride precipitate, and the test passed if no flocculent precipitate was observed
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The detection sensitivity of this test method is 0.
0003%
.

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2 Reagents and materials

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2.
1 Nitric acid :

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2.
2 Anhydrous methanol ;

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3 Saturated silver nitrate solution;

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4 Connecting pipeline: polytetrafluoroethylene (PTFE) pipe with an inner diameter of 0.
15mm～0.
20mm
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3 Apparatus and equipment

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1 Sampling cylinder: same as 4.
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4;

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2 Electronic balance: the maximum weighing is not less than 3000g, and the sensitivity is 0.
1g
.

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4 Analysis steps

Add 30 mL of anhydrous methanol to a 100 mL beaker, add 18 drops of saturated silver nitrate solution and 6 drops of nitric acid under stirring
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Weigh the mass of the sampling cylinder containing the sample to the nearest 0.
1g
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Connect one end of the connecting line to the outlet valve of the sampling cylinder (note that each joint is well sealed), and insert the other end into the beaker solution; open the outlet valve of the sampling cylinder while stirring, and bubbling injection, the injection volume is about 37g, and the sampling time should be different Less than 15min
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Observe whether there is white flocculent precipitation in the beaker
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If there is no white flocculent precipitate in the solution, the test is qualified
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