This method is suitable for the determination of trace oxygen, argon and nitrogen in electronic grade hydrogen. This method can be used to simultaneously determine methane, carbon monoxide and carbon dioxide, with a minimum detection amount of 0.01ppm. SJ 2805-1987 Determination of trace oxygen + argon and nitrogen in electronic grade hydrogen Variable temperature concentration chromatography SJ2805-1987 Standard download decompression password: www.bzxz.net
This method is suitable for the determination of trace oxygen, argon and nitrogen in electronic grade hydrogen. This method can be used to simultaneously determine methane, carbon monoxide and carbon dioxide, with a minimum detection amount of 0.01ppm.

The standard of the Ministry of Electronic Industry of the People's Republic of China for the determination of trace oxygen, argon and nitrogen in electronic grade hydrogen. Variable temperature concentration chromatography
This method is suitable for the determination of trace oxygen, argon and nitrogen in electronic grade hydrogen. This method can be used to determine methane, monoxide and carbon dioxide at the same time, with the minimum detection amount of 0.01ppm. 1 Principle of the method
$J280—87
1.1 This method is variable temperature concentration chromatography. The carrier gas carries the sample through the chromatographic column to separate the components and then enter the thermal conductivity detector.
1.2 The thermal conductivity detector is made based on the principle that the thermal conductivity of other components changes when they are added. When the sample and the carrier gas are reversely introduced into the thermal conductivity cell, due to the different thermal conductivities of the two, the temperature of the thermistor changes, causing its resistance to change accordingly, and the output signal is measured by the Wheatstone bridge.
1.3 This method uses a concentration technique to improve sensitivity, that is, under low-pressure conditions, impurities are enriched on the concentrator to increase the injection volume. When the concentration is 196℃, the sieve has a good adsorption capacity for hydrogen and nitrogen. 1.4 Hydrogen is used as the carrier gas for manganese spectrum analysis.
2 Receiver and materials
2.1 Next-generation phase chromatograph
& thermal conductivity detector.
h. Chromatographic column: stainless steel tube, inner diameter of 4mm, length of 1.5~3m, carrier is 54 molecular sieve or polymer microsphere 60c80H.
c, recorder or microprocessor, 0eo1mV. 2.2 Relatively high oxygen storage material or ultra-high dead hydrogen.
2.3 Sampler: 2~4g of 40c360 mesh polymer microspheres in a glass or metal tube, both ends plugged with high purity quartz cloth 2.4 Wet gas flow meter.
2.5 Cold source: liquid nitrogen.
3 Process block diagram and test parts
3.1 See Figure 1 for the process block diagram.
Package spectrum stack
Tester
Figure 1 Flow chart for determination of trace oxygen, nitrogen and nitrogen in electronic grade hydrogen 3.2 Test conditions
Published by the Ministry of Electronics Industry on May 18, 1987
Implemented on January 1, 1988
Bridge current: 180～200mA,
Gas flow rate: 40~60ml/mimg
Paper speed: 5mm/mln;
Decrease: 1:
Detection temperature, room temperature 15~35℃
Music Steps
Quartz
High-resolution microsphere
SJ2B05---8T
A: Sample gas cylinder
B: Needle valve
C. Concave piston concentration sampling tube
E, temperature gas flow meter
Variable temperature concentration sampling device
Quartz cloth
Commercial molecular microsphere
Four-way piston concentration sampling tube
SJ2805-81
4.1 Purge gas path According to Figure 2, hard-connect or ground-connect system, liquid shrinkage is temporarily closed. Open the hydrogen valve, the flow rate is about 10001/min for half an hour. Reduce the flow rate to 800m1/min, open the four-way piston (see Figure 3), and allow hydrogen to pass through the adsorbent in the sampler to purge the air in it for half an hour. Further adjust the flow rate to less than 800m1/min. 4.2 Sampling Slowly put on the cold source and start counting time. When the wet gas flowmeter indicates that the gas volume reaches the requirement, turn off the gas source and remove the cold source at the same time. When about 100m1 of gas is discharged from the sample tube, immediately close the piston and remove the sampling tube. 4.3 Desorb the concentration tube in room temperature water or a hair dryer for 3 to 5 minutes, connect the concentration tube to the chromatograph injection port with a hard connection, and exhaust the air peak first. Open the four-way piston of the concentration tube for injection, wait for the sample peak to be discharged, and use a micro-injector to inject air as a standard sample.
5 Calculation results
nitrogen content in air
oxygen content in air
where:
XV/X79% X
-×VX21%×
Assume that the volume of standard air sample is V3, μ1,
nitrogen peak area of ​​standard air sample Amm, oxygen + argon peak area Az, mm2: sample volume V, 1;
nitrogen peak area of ​​sample A1, mm2; oxygen + argon peak area A2, nm221% constant is the percentage content of oxygen in the air
79% constant is the percentage content of nitrogen in the air. 6 Analytical precision
The arithmetic mean of three parallel determinations is the determination result, and the relative deviation is not more than ±1. 7
Test report
7.1 The test report includes the following contents:
4, time, place, unit, date,
b. Sampling method and number
Type and model of instrument used:
d. Test conditions and results;
chemical analysis, if the signature.
.8 Attention items
(2)
8.1 The chromatographic column must be well activated. The activation conditions are hydrogen flow rate of 501/111, temperature of about 200℃, activation time of 2h
B.2 The adsorbent in the sampling tube should be activated. The activation conditions are nitrogen flow rate of 60m1/min, leakage of about 180℃, activation for 7~8h, until there is no moisture on the tube wall. 8.3 The cylinder must be equipped with a needle valve flow regulating disk, otherwise the dead volume will be large and the gas path will be difficult to purge clean. 8.4 The system must be hard-connected to prevent air leakage. The ground mouth and four-way piston must be sealed with silicone grease or other lubricating grease to fit tightly. 9 See Figure 4 for a typical chromatogram.
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Sampling 15
Figure 4 Typical chromatogram for the determination of trace fluorine + chlorine and heavy nitrogen in electronic-grade fluorine
This standard was proposed by the Clean Technology Society of the Chinese Institute of Electronics and sponsored by the Standardization Institute of the Ministry of Electronics Industry. This standard was drafted and revised by Yin Enhua and Yang Xuezhen from the Institute of Conductors, Chinese Academy of Sciences, and Zhao Changchun from the Institute of Standardization and Chemistry of the Ministry of Electronics Industry.
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