Method for quantitatively measuring hydrogen, deuteration hydrogen and deuterium hydrogen isotope element

Abstract

The invention relates to an quantitative determination method of the isotope of hydrogen, hydrogen deuteride and hydrogen deuterium, which comprises using neon gas to be carrier gas, leading a gas chromatograph to adopt a double-strut double-temperature system, choosing 50 DEG C sampling temperature, sampling through an injector or a gas sampling valve, and the sampling quantity is 0.1-2.2mL, sample gas which is separated by a gas-chromatography column generates electrical signals through a detector, recording the pear areas of hydrogen, hydrogen deuteride and deuterium gas of chromatogram peaks through a chromatogram working station after the electrical signals are magnified through a front magnifier, adopting a volume correction factor normalization method or an external standard method to measure the content of hydrogen (H2), hydrogen deuteride (HD) and deuterium (D2), and getting detection results. The invention has the advantages of excellent separation effect of hydrogen isotope and high detection sensitivity, the detection of the pureness of deuterium gas can reach more than 99.99%, hydrogen deuteride (HD) and deuterium (D2) are sampled in big dosage, the peaks are not overlapped, thereby guaranteeing the quantitative detection of high-purity deuterium gas, and standard gas is not needed to be prepared in the process of detecting. The method simplifies the operation process, which is convenient for on-line detection of deuterium gas in the process of producing.

Description

technical field [0001] The invention relates to a method for quantitatively detecting hydrogen, deuterated hydrogen and deuterium hydrogen isotopes by using a gas chromatograph. Background technique [0002] The method for detecting hydrogen isotopes by gas chromatography is to use helium (He) as the carrier gas, use γ-Al2O3-Fe2O3, 13X molecular sieves at liquid nitrogen temperature (-196°C), and use 4A molecular sieves at -110 to -160°C. And manganese salt modified γ-Al2O3 is the chromatographic column of adsorbent for hydrogen (H2), deuterated hydrogen (HD), tritiated hydrogen (HT), deuterium (D2), tritiated deuterium (DT) and tritium (T2 ) six hydrogen isotope molecular gases are separated and detected by a thermal conductivity cell detector. The problems existing in the existing detection method are: 1. Although good resolution can be obtained on the chromatographic column by using helium as the carrier gas, because the molecular weight of helium is close to the hydroge...

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Problems solved by technology

The problems existing in the existing detection method are: 1. Although good resolution can be obtained on the chromatographic column by using helium as the carrier gas, because the molecular weight of helium is close to the hydrogen isotope, its thermal conductivity difference is not large, and the hydrogen isotope The signal response on the thermal conductivity cell detector is small, so it is not conducive to the detection of trace components; 2. The quality of hydrogen isotope separation directly affects the effect of gas chromatography quantitative detection. In order to improve the separation effect of hydrogen isotopes, gas chromatography Work at the temperature of liquid nitrogen, that is, both the analytical column and the reference column are placed in the liquid nitrogen tank, but hydrogen (H2), deuterated hydrogen (HD) and deuterium (D2) exist at the liquid nitrogen temperature for a longer retention time , the peak is wider, and the detection sensitivity is relatively low

[0003] In May 2006, a report on hydrogen isotope analysis was published in the Chinese "Chemical Analysis" journal. The chromatographic column filled with manganese salt-modified γ-Al2O3 was used under the conditions of carrier gas flow rate of 110mL / min and injection volume of 0.1mL. , the retention times of hydrogen (H2), deuterated hydrogen (HD) and deuterium (D2) are 66s, 79s and 94s. When the injection volume is greater than 0.1mL, the peaks will partially overlap and affect quantitative detection; at the same time, at a detection temperature of 120°C, Under the condition of bridge flow 180mA, the detection sensitivity of hydrogen (H2), deuterated hydrogen (HD) and deuterium (D2) is only 2000-5000ppm, and the detection of deuterated hydrogen in deuterium can only reach about 3000ppm; the components used in the analysis Deuterated hydrogen (HD) is prepared by heating deuterium and hydrogen in the presence of a palladium catalyst. The method prepares deuterated hydrogen with many equipment and complicated operations, which is unfavorable for routine analysis. The external standard method is used to determine the hydrogen isotope hydrogen ( H2), deuterated hydrogen (HD) and deuterium (D2) content, need to determine the standard curve or each determination needs to be calibrated with the prepared standard gas

[0004] Using the above method to detect hydrogen isotopes, the detection of deuterium content can only reach 99-99.9%

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