阅读说明：本技术 一种检测氯气中氢气和氧气的方法 (Method for detecting hydrogen and oxygen in chlorine ) 是由 张刚 贾启 孔涛 单维波 徐风祥 卢洪顺 于 2020-06-11 设计创作，主要内容包括：本发明涉及一种检测氯气中氢气和氧气的方法,属于气体含量检测的技术领域。本发明采用了气相色谱仪进行检测,首先将待测气体经过色谱柱①,将氯气与其他气体进行分离,分离后的氯气会排出,其他气体进入色谱柱②进行分离检测。通过此方法,实现了对氯气中所含的微量气体进行含量的检测,避免使用爆炸法这种危险的检测方法；通过长期的工作的实践,本发明的方法重现性好,检验结果稳定可靠；本发明的检测速度快,操作简单；分析方便、快捷。(The invention relates to a method for detecting hydrogen and oxygen in chlorine, belonging to the technical field of gas content detection. The invention adopts a gas chromatograph for detection, firstly, gas to be detected passes through a chromatographic column I, chlorine gas is separated from other gases, the separated chlorine gas is discharged, and other gases enter the chromatographic column II for separation detection. By the method, the content of trace gas contained in chlorine is detected, and the dangerous detection method of an explosion method is avoided; through the practice of long-term work, the method has good reproducibility and stable and reliable detection results; the invention has fast detection speed and simple operation; the analysis is convenient and fast.)

1. A method for detecting hydrogen and oxygen in chlorine is characterized by comprising the following steps:

gas chromatograph: agilent 7820A;

gas marking: h₂：0.0478％，O₂：0.762％，N₂: 0.0882%, the rest gas is CO₂；

Chromatographic conditions are as follows: carrier gas: argon gas; flow rate of carrier gas: 10 mL/min; tail gas flow velocity (N)₂) 5mL/min, a sample inlet temperature of 150 ℃, a chromatographic column ①, an activated carbon packed column of 0.5m × 3mm, a chromatographic column ②, a 5A molecular sieve packed column of 2m × 3mm, a column box temperature of 80 ℃, a bridge current of 100mA, a detector of 200 ℃, a detector of TCD, and a sample injection mode of a ten-way valve;

the specific operation steps are as follows:

(1) opening an argon main valve, and adjusting a partial pressure valve to enable the pressure of the partial pressure valve to be 1-2 MPa;

(2) opening the gas chromatograph, setting the flow rate of carrier gas, introducing the carrier gas for 30min after the setting is finished, and balancing the base line; then setting the temperature of the sample inlet, the temperature of the column box, the bridge current and the parameters of the detector;

(3) checking whether parameters of the sample inlet temperature, the column box temperature, the bridge current and the detector temperature are normal; after the baseline is stable, sample injection analysis is prepared; introducing standard gas; the sample injection amount is 0.25-1.5 mL, the detection time is set to be 5-10 min, a star key is clicked to start operation, and a standard gas spectrum is used as a calibration curve;

(4) after the curve is calibrated, introducing gas to be detected, setting the sample injection amount to be 0.25-1.5 mL and the detection time to be 5-10 min, and clicking a star key to start operation;

(5) clicking an analysis option after the sample is tested, automatically integrating, and storing a detection result; then, repeating the detection once, and taking the average value of the detection results of the two times as a report value;

(6) after the test is finished, the power supply is turned off, then the carrier gas is introduced for 30min to cool the instrument, finally the carrier gas valve is closed, and the detection is finished.

2. The method of claim 1, wherein the carrier gas flow rate is measured by a soap film flow meter.

3. The method of claim 1, wherein the amount of the standard gas introduced in step (3) is 1.0 mL.

4. The method for detecting hydrogen and oxygen in chlorine as claimed in claim 1, wherein the detection time in step (3) is set to 6 min.

5. The method for detecting hydrogen and oxygen in chlorine as claimed in claim 1, wherein the sample volume of the gas to be detected in step (4) is 1.0 mL.

6. The method for detecting hydrogen and oxygen in chlorine as claimed in claim 1, wherein the detection time in step (4) is set to 6 min.

Technical Field

The invention belongs to the technical field of gas content detection, and particularly relates to a method for detecting hydrogen and oxygen in chlorine.

Background

Chlorine gas is industrially obtained by electrolysis of saturated brine. Hydrogen is simultaneously generated during the electrolysis of the saturated brine, and if hydrogen leakage occurs in the electrolytic membrane during the electrolysis, the explosion range of hydrogen is reached. The explosion limit of hydrogen under the irradiation of sunlight in chlorine is 9.8-52.8%, and even when the chlorine is mixed with more than 5% of hydrogen, the chlorine can explode when meeting strong light, so that safety production accidents are caused. Therefore, it is important to accurately determine the hydrogen content of chlorine gas.

Disclosure of Invention

Aiming at the problems of large error and high risk in hydrogen content determination by a combustion method in the prior art, the invention provides a method for detecting hydrogen and oxygen in chlorine, so as to solve the problems. The invention adopts the gas chromatograph for detection, has simple and convenient operation, high speed, high result accuracy and no safety risk.

A method for detecting hydrogen and oxygen in chlorine comprises the following specific steps:

gas chromatograph: agilent 7820A;

gas marking: h₂：0.0478％，O₂：0.762％，N₂: 0.0882%, the rest gas is CO₂；

Chromatographic conditions are as follows: carrier gas: argon gas; flow rate of carrier gas: 10 mL/min; tail gas flow velocity (N)₂) 5mL/min, a sample inlet temperature of 150 ℃, a chromatographic column ① which is an activated carbon packed column of 0.5m × 3mm, a chromatographic column ② which is a 5A molecular sieve packed column of 2m × 3mm, a column box temperature of 80 ℃, a bridge current of 100mA, a detector of 200 ℃, a detector of TCD and a sample injection mode of a ten-way valve.

The specific operation steps are as follows:

(1) opening an argon main valve, and adjusting a partial pressure valve to enable the pressure of the partial pressure valve to be 1-2 MPa;

(2) opening the gas chromatograph, setting the flow rate of carrier gas, introducing the carrier gas for 30min after the setting is finished, and balancing the base line; then setting the temperature of the sample inlet, the temperature of the column box, the bridge current and the parameters of the detector;

(3) checking whether parameters of the sample inlet temperature, the column box temperature, the bridge current and the detector temperature are normal; after the baseline is stable, sample injection analysis is prepared; introducing standard gas; the sample injection amount is 0.25-1.5 mL, the detection time is set to be 5-10 min, a star key is clicked to start operation, and a standard gas spectrum is used as a calibration curve;

(4) after the curve is calibrated, introducing gas to be detected, setting the sample injection amount to be 0.25-1.5 mL and the detection time to be 5-10 min, and clicking a star key to start operation;

(5) clicking an analysis option after the sample is tested, automatically integrating, and storing a detection result; then, repeating the detection once, and taking the average value of the detection results of the two times as a report value;

(6) after the test is finished, the power supply is turned off, then the carrier gas is introduced for 30min to cool the instrument, finally the carrier gas valve is closed, and the detection is finished.

Preferably, the carrier gas flow rate is measured by a soap film flow meter.

Preferably, the sample amount of the standard gas in the step (3) is 1.0 mL.

Preferably, the detection time in step (3) is set to 6 min.

Preferably, the sample volume of the gas to be measured in the step (4) is 1.0 mL.

Preferably, the detection time in the step (4) is set to 6 min.

The detection principle of the invention is as follows: firstly, gas to be detected passes through a chromatographic column I, chlorine is separated from other gases, the separated chlorine is discharged, and other gases enter the chromatographic column II for separation and detection. By the method, the content of trace gas contained in chlorine is detected, and the corrosion of the chlorine to chromatographic columns and equipment is avoided.

The invention has the beneficial effects that:

(1) the invention adopts the gas chromatography to detect and analyze the hydrogen and the oxygen in the chlorine, thereby avoiding the dangerous detection method of an explosion method.

(2) Through long-term working practice, the method for detecting the content of hydrogen and oxygen in chlorine has good reproducibility and stable and reliable detection results, and the detection error of the method is controlled within 0.05% through long-term detection statistics.

(3) The method for detecting the content of hydrogen and oxygen in the chlorine has the advantages of high detection speed and simple operation. The analysis is convenient and quick, and the detection time of each batch is only 5-10 min.

Drawings

In order to more clearly illustrate the embodiments or technical solutions in the prior art of the present invention, the drawings used in the description of the embodiments or prior art will be briefly described below, and it is obvious for those skilled in the art that other drawings can be obtained based on these drawings without creative efforts.

FIG. 1 first test profile of example 1 of the present invention;

FIG. 2 is a second detection profile of example 1 of the present invention;

FIG. 3 first test pattern of example 2 of the present invention;

FIG. 4 is a second test pattern of example 2 of the present invention.

Detailed Description

In order to make those skilled in the art better understand the technical solution of the present invention, the technical solution in the embodiment of the present invention will be clearly and completely described below with reference to the drawings in the embodiment of the present invention, and it is obvious that the described embodiment is only a part of the embodiment of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.