Detection device and detection method for chlorine isotope abundance in sodium chloride

Abstract

The present invention belongs to the technical field of isotope detection devices, and specifically relates to a detection device for chlorine isotope abundance in sodium chloride and a detection method thereof, comprising: a reaction container; the reaction container comprises a tank body and an end cover sealed with the tank body; the end cover is provided with a first through hole, a second through hole and a third through hole; a first sample tube and a second sample tube connected to each other at the middle are arranged in the tank body, and a connected sealing area is formed above the first sample tube and the second sample tube; wherein the first through hole introduces a long tube to the bottom of the first sample tube; the second through hole is arranged on a side of the end cover away from the first through hole; the first through hole, the second through hole and the third through hole all connect the sealing area with the outside; the present invention obtains accurate data through infrared spectrum detection while eliminating the strict laboratory requirements of a conventional mass spectrometer.

Description

Technical Field

[0001] The invention belongs to the technical field of isotope detection devices, and in particular relates to a detection device and a detection method for chlorine isotope abundance in sodium chloride. Background Art

[0002] At present, the world generally adopts the standard mean marine chlorine (SMOC) as the stable chlorine isotope standard. The main method for testing the chlorine isotope abundance in sodium chloride is mass spectrometry. The mass spectrometry method detects the chlorine isotope abundance in sodium chloride, and the sample pretreatment process is complicated and costly. Generally, the chloride ions and methane gas must react to generate chloromethane before it can be sent to the isotope mass spectrometer for detection. In addition, during the detection process, the chlorine element damages the instrument, affecting the instrument life and detection accuracy.

[0003] More importantly, mass spectrometry instruments are complex, expensive, and have high requirements for the experimental environment, making them difficult to deploy on-site and conduct real-time detection.

[0004] Therefore, overcoming the problem of difficult and accurate detection of chlorine isotope abundance in sodium chloride in non-laboratory environments is a technical problem that urgently needs to be solved in this field.

[0005] It should be noted that the above information disclosed in this background technology section is only used to understand the background technology of the present application concept, and therefore, the above description is not considered to constitute information of the prior art. Summary of the invention

[0006] The embodiments of the present disclosure at least provide a device and method for detecting the isotope abundance of chlorine in sodium chloride.

[0007] In the first aspect, the embodiment of the present disclosure provides a detection device for the isotopic abundance of chlorine in sodium chloride, comprising: a nitrogen bottle, a pressure regulating valve, a mass flow controller, a two-position four-way valve, a first three-way joint connected to the first outlet of the two-position four-way valve and a second three-way joint connected to the second outlet respectively connected in sequence; the second three-way joint is connected to a reaction container; the reaction container comprises a tank body and an end cover sealed with the tank body; a first through hole, a second through hole and a third through hole are opened on the end cover; a first sample tube and a second sample tube connected to each other in the middle are arranged in the tank body, and a connected sealing area is formed above the first sample tube and the second sample tube; the first through hole introduces a long tube to the bottom of the first sample tube; the second through hole is arranged on the side of the end cover away from the first through hole; the first through hole, the second through hole and the third through hole all connect the sealed area with the outside; the first three-way joint is connected to a spectrometer; the third through hole is used for an injection needle to extract gas from the sealed area, and the gas enters the spectrometer after passing into the first three-way joint.

[0008] In an optional embodiment, the tank body is made of quartz.

[0009] In an optional embodiment, the first through hole, the second through hole and the third through hole are all provided with fixing members.

[0010] In an optional embodiment, a sealing ring is provided between the end cover and the tank body.

[0011] In an optional embodiment, a plurality of the reaction containers are grouped together, and the tank body is partially disposed in a metal container; and a heating plate is disposed on the outer wall of the metal container.

[0012] In an optional embodiment, valves are provided on the first through hole and the second through hole; the second three-way joint is connected to the first through hole to allow gas to enter and be discharged from the second through hole.

[0013] In an optional embodiment, the second three-way connector is also connected to a pressure gauge.

[0014] In an optional embodiment, the spectrometer is a Fourier transform infrared spectrometer.

[0015] In a second aspect, the disclosed embodiment also provides a method for detecting the isotopic abundance of chlorine in sodium chloride, which is applied to the detection device as described above, and comprises the following steps: step S1, placing the NaCl sample to be tested and concentrated sulfuric acid in a first sample tube and a second sample tube, respectively, and sealing them; step S2, opening the valve of the nitrogen bottle, adjusting the outlet pressure of the pressure regulating valve to 0.3-0.4 MPa, and setting the flow rate of the mass flow controller to 100-150 ml / min, and respectively purging the water vapor in the reaction container and the spectrometer; step S3, tilting the reaction container so that the concentrated sulfuric acid in the second sample tube flows into the first sample tube to generate HCl, and wait for the reaction for 10-15 min; step S4, using an injection needle to extract 1-5 μL of gas from the third through hole, injecting it into the first three-way joint and flowing it into the spectrometer for detection.

[0016] The beneficial effect of the present invention is that the detection device and detection method of chlorine isotope abundance in sodium chloride are simple and do not need to be converted into chloromethane through a complex process. Infrared spectrum detection can obtain accurate data while eliminating the strict laboratory requirements of conventional mass spectrometers. Spectral detection can also reduce the corrosion effect of chlorine on instruments and equipment; in addition, the detection method can avoid the influence of impurities generated in the HCl gas reaction, and can also overcome the problem of inaccurate accuracy caused by external reactions, and can be applied on a large scale in field tests.

[0017] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention are realized and obtained by the structures particularly pointed out in the description, claims and drawings.

[0018] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 A cross-sectional view of a reaction container of a device for detecting chlorine isotope abundance in sodium chloride provided in an embodiment of the present disclosure;

[0021] Figure 2 A schematic diagram of the structure of a reaction container of a device for detecting chlorine isotope abundance in sodium chloride provided in an embodiment of the present disclosure;

[0022] Figure 3 A schematic diagram of the structure of a reaction container of a device for detecting chlorine isotope abundance in sodium chloride provided in an embodiment of the present disclosure;

[0023] Figure 4 A schematic diagram of the structure of a device for detecting the isotopic abundance of chlorine in sodium chloride provided in an embodiment of the present disclosure.

[0024] In the figure:

[0025] 100, reaction container; 110, tank body; 111, first sample tube; 112, second sample tube; 120, end cover; 121, first through hole; 122, second through hole; 123, third through hole; 124, valve; 140, fixing member; 150, sealing ring; 160, metal container;

[0026] 200, nitrogen cylinder; 300, pressure regulating valve; 400, mass flow controller; 500, two-position four-way valve; 511, first outlet; 512, second outlet; 610, first three-way connector; 620, second three-way connector; 621, pressure gauge; 700, spectrometer; 800, injection needle. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] As used herein, the phrases "in one embodiment," "according to one embodiment," "in some embodiments," and the like generally refer to the fact that the particular feature, structure, or characteristic following the phrase may be included in at least one embodiment of the present disclosure. Therefore, a particular feature, structure, or characteristic may be included in more than one embodiment of the present disclosure, so that these phrases do not necessarily refer to the same embodiment. As used herein, the terms "example," "exemplary," and the like are used to "serve as an example, instance, or illustration." Any implementation, aspect, or design described herein as "example" or "exemplary" is not necessarily to be construed as preferred or superior to other implementations, aspects, or designs. On the contrary, the use of the terms "example," "exemplary," and the like is intended to present concepts in a concrete manner.

[0029] Herein, example embodiments of the present disclosure will be described in more detail with reference to the accompanying drawings. As used herein, expressions such as "at least one of..." modify the entire list of elements when following a list of elements, rather than modifying individual elements in the list. For example, the expression "at least one of a, b, and c" should be understood to include only a, only b, only c, both a and b, both a and c, both b and c, or all of a, b, and c.

[0030] The terms used herein are only used to describe specific exemplary configurations and are not intended to be limited. As used herein, the singular articles "one", "an" and "the" may also be intended to include plural forms, unless it is clearly indicated above that this is not the case. The terms "comprise", "include" and "have" are inclusive, and therefore specify the presence of features, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components and / or combinations thereof. The method steps, processes and operations described herein should not be interpreted as necessarily requiring them to be performed in the specific order discussed or shown, unless specifically identified as an execution order. Additional or alternative steps may be adopted.

[0031] Patent CN202310265684.7 "Sample preparation system, method and detection method of chlorine isotopes in chlorinated hydrocarbons based on infrared spectroscopy" reports a device and method for detecting chlorine isotopes in chlorinated hydrocarbons by infrared spectroscopy, but this method is not suitable for detecting the abundance of chlorine isotopes in sodium chloride.

[0032] The above patent is to seal the mixture of chlorinated hydrocarbon sample and hydrogen in a quartz tube, heat it at 900 degrees Celsius to produce a hydrogenation reaction, and then use spectroscopy to detect the abundance of chlorine isotopes in the generated HCl gas; the quartz tube is not only a hydrogenation reaction container, but also the place where HCl gas produces an absorption peak for mid-infrared light during spectral detection. Therefore, the windows at both ends of the quartz tube must always be kept clean and transparent to allow mid-infrared light to penetrate.

[0033] However, when detecting chlorine isotopes in sodium chloride, sodium chloride needs to be mixed with concentrated sulfuric acid to generate HCl gas. If sodium chloride and concentrated sulfuric acid are placed in the quartz tube of the above patent, sealed and reacted, although HCl gas can be generated, the residual sodium chloride powder, the generated sodium bisulfate or sodium sulfate solid, and the residual concentrated sulfuric acid will seriously contaminate the window of the quartz tube, making it impossible to use spectroscopy to detect the abundance of chlorine isotopes in the generated HCl gas;

[0034] If sodium chloride and concentrated sulfuric acid are reacted in an external container, and the above-mentioned patented device is used to blow the generated HCl gas into a quartz tube and then seal it for detection, since the volume of the gas contained in the quartz tube is limited, and the gas pressure inside the quartz tube needs to be controlled to reach an appropriate value, the concentration of HCl blown into the quartz tube needs to be controlled to be appropriate, and all the generated HCl gas needs to be controlled to enter the quartz tube to avoid isotope fractionation that affects the detection results, it is difficult to achieve all of these requirements in the actual operation process.

[0035] The defects existing in the above solutions are the results obtained by the inventor after practice and careful research. Therefore, the discovery process of the above problems and the solutions proposed by the present disclosure for the above problems below should be the contributions made by the inventor to the present disclosure during the disclosure process.

[0036] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0037] Some embodiments of the present invention are described in detail below. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0038] See also Figure 1 and Figure 4 ,like Figure 1 and Figure 4As shown, the embodiment of the present disclosure provides a detection device for the isotopic abundance of chlorine in sodium chloride, comprising: a nitrogen bottle 200, a pressure regulating valve 300, a mass flow controller 400, a two-position four-way valve 500, a first three-way joint 610 connected to a first outlet 511 of the two-position four-way valve 500 and a second three-way joint 620 connected to a second outlet 512, which are connected in sequence; the second three-way joint 620 is connected to a reaction container 100; the reaction container 100 comprises a tank body 110 and an end cover 120 sealed with the tank body 110; the end cover 120 is provided with a first through hole 121, a second through hole 122 and a third through hole 123; the tank body 110 is provided with The first sample tube 111 and the second sample tube 112 are connected in the middle, and a connected sealing area is formed above the first sample tube 111 and the second sample tube 112; wherein the first through hole 121 introduces a long tube to the bottom of the first sample tube 111; the second through hole 122 is arranged on the side of the end cover 120 away from the first through hole 121; the first through hole 121, the second through hole 122 and the third through hole 123 all connect the sealing area with the outside; the first three-way joint 610 is connected to the spectrometer 700; the third through hole 123 is used for the injection needle 800 to extract the gas in the sealing area, and after passing into the first three-way joint 610, the gas enters the spectrometer 700.

[0039] In some embodiments, specifically, a distance is maintained between the long tube introduced into the first through hole 121 and the bottom of the first sample tube 111 to avoid contact between the sample contained in the first sample tube 111 and the long tube.

[0040] In some embodiments, specifically, the material of the tank body 110 is quartz, and quartz products are used as reaction containers, which have the characteristics of high temperature resistance and corrosion resistance, and are convenient for observing the internal reaction conditions. It can be used as a sample reaction site and also as a storage container for HCl gas. The reactants are sealed in the container, and the experiment is highly safe. The start time of the reaction can be controlled at any time, and there is no need to inject concentrated sulfuric acid through a sampling needle or the like, which can reduce the risk and is not easy to introduce external water vapor again.

[0041] In some embodiments, specifically, the first through hole 121 , the second through hole 122 and the third through hole 123 are all provided with fixing members 140 for fixing the gas pipeline inserted from the outside.

[0042] In some embodiments, specifically, a sealing ring 150 is provided between the end cover 120 and the tank body 110 .

[0043] See also Figure 3 ,like Figure 3As shown, specifically, several of the reaction containers 100 are grouped together, and the tank body 110 is partially disposed in a metal container 160. The number of the reaction containers 100 can be set to 1-10 to perform multiple groups of reactions simultaneously. A heating plate is disposed on the outer wall of the metal container 160 to accelerate the removal of water vapor.

[0044] See also Figure 2 ,like Figure 2 As shown, specifically, the fixing member 140 on the first through hole 121 and the second through hole 122 is provided with a valve 124 ; the second three-way joint 620 is connected with the first through hole 121 to allow gas to enter and be discharged from the second through hole 122 .

[0045] In some embodiments, specifically, the second three-way connector 620 is also connected to a pressure gauge 621 .

[0046] In some embodiments, specifically, the spectrometer 700 is a Fourier transform infrared spectrometer.

[0047] The disclosed embodiment also provides a method for detecting the isotopic abundance of chlorine in sodium chloride, which is applied to the detection device as described above, and comprises the following steps: step S1, placing the NaCl sample to be tested and concentrated sulfuric acid in a first sample tube and a second sample tube, respectively, and sealing them; step S2, opening the valve of the nitrogen bottle, adjusting the outlet pressure of the pressure regulating valve to 0.3-0.4 MPa, and setting the flow rate of the mass flow controller to 100-150 ml / min, and respectively purging water vapor in the reaction container and the spectrometer; step S3, tilting the reaction container to allow the concentrated sulfuric acid in the second sample tube to flow into the first sample tube to generate HCl, and waiting for the reaction for 10-15 min; step S4, using an injection needle to extract 1-5 μL of gas from the third through hole, injecting it into the first three-way joint and flowing it into the spectrometer for detection.

[0048] Step S1, prepare the sample. According to the amount of HCl sample required for the experiment, weigh a certain mass of sodium chloride sample and put it into the first sample tube of the reaction container. Use a rubber-tipped dropper to absorb a certain amount of concentrated sulfuric acid and then drip it into the second sample tube of the reaction container. Add a sealing ring between the end cover and the tank body and tighten it; install two manual valves and pipelines, and tighten the fixings to ensure sealing. The two manual valves remain closed. Install the injection pad and tighten the fixings to ensure sealing.

[0049] Step S2, removing moisture from the reaction container, opening the valve of the nitrogen bottle, adjusting the outlet pressure of the pressure regulating valve to 0.3-0.4Mpa, opening two manual valves on the reaction container, opening the two-position four-way valve, setting the flow rate of the mass flow controller to 100ml / min, and introducing nitrogen into the reaction container to purge the internal water vapor for 2 hours; to improve the dehydration efficiency, the reaction container should be placed in a heating device, and the temperature is set to 60-80 degrees, which can accelerate the evaporation efficiency of the residual water vapor inside the reaction container; to process multiple groups of samples at one time and improve the detection efficiency, multiple reaction containers with samples placed in them can be placed in the heating device, and all the manual valves of the reaction container inlet are connected together through pipelines and connected to the second three-way joint. The manual valves of multiple reaction containers are kept open, so that the residual water of multiple reaction containers can be removed at the same time, saving time.

[0050] Step S3, react to produce HCl, close the two-position four-way valve, allow the nitrogen flowing out of the mass flow controller to flow into the spectrum through the first three-way joint, purge the spectrum, and prepare for sampling. For the reaction container after removing the residual water vapor, close the two manual valves, take out and pour the reaction container, allow the concentrated sulfuric acid to flow into the first sample tube of sodium chloride through the opening between the two sample tubes, react to generate HCl, and wait for the reaction for about 10 minutes.

[0051] Step S4, injection, use the injection needle to extract 1uL of sample from the reaction container, inject it into the injection port of the first three-way connector, and the HCl sample then flows into the spectral detection.

[0052] In summary, the detection device and detection method of chlorine isotope abundance in sodium chloride can obtain accurate data through infrared spectrum detection while eliminating the strict laboratory requirements of conventional mass spectrometers. Spectral detection can also reduce the corrosion effect of chlorine on instruments and equipment; in addition, the detection method can avoid the influence of impurities generated in the HCl gas reaction, and can also overcome the problem of inaccuracy caused by external reactions, and can be applied on a large scale in field tests.

[0053] Based on the above ideal embodiments of the present invention, the relevant staff can make various changes and modifications without departing from the technical concept of the present invention through the above description. The technical scope of the present invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A detection device for chlorine isotope abundance in sodium chloride, characterized in that: include: A nitrogen cylinder (200), a pressure regulating valve (300), a mass flow controller (400), a two-position four-way valve (500), a first three-way connector (610) connected to a first outlet (511) of the two-position four-way valve (500), and a second three-way connector (620) connected to a second outlet (512) respectively, connected in sequence; The second three-way connector (620) is connected to a reaction container (100); The reaction container (100) comprises a tank body (110) and an end cover (120) sealed with the tank body (110); The end cover (120) is provided with a first through hole (121), a second through hole (122) and a third through hole (123); The tank body (110) is provided with a first sample tube (111) and a second sample tube (112) which are connected to each other at the middle, and a sealed area is formed above the first sample tube (111) and the second sample tube (112); wherein The first through hole (121) introduces a long tube to the bottom of the first sample tube (111); The second through hole (122) is arranged on a side of the end cover (120) away from the first through hole (121); The first through hole (121), the second through hole (122) and the third through hole (123) all allow the sealing area to communicate with the outside world; The second three-way joint (620) is in communication with the first through hole (121) to allow gas to enter and be discharged from the second through hole (122). The first three-way connector (610) is connected to a spectrometer (700); The third through hole (123) is used for the injection needle (800) to extract gas from the sealed area and pass the gas into the first three-way connector (610) to allow the gas to enter the spectrometer (700).

2. The detection device for chlorine isotope abundance in sodium chloride as claimed in claim 1, characterized in that, The tank body (110) is made of quartz.

3. The detection device for chlorine isotope abundance in sodium chloride as claimed in claim 1, characterized in that, The first through hole (121), the second through hole (122) and the third through hole (123) are all provided with fixing parts (140).

4. The detection device for chlorine isotope abundance in sodium chloride as claimed in claim 1, characterized in that, A sealing ring (150) is provided between the end cover (120) and the tank body (110).

5. The detection device for chlorine isotope abundance in sodium chloride as claimed in claim 1, characterized in that, A plurality of the reaction containers (100) are grouped together, and the tank body (110) is partially disposed in the metal container (160); The outer wall of the metal container (160) is provided with a heating plate.

6. The detection device for chlorine isotope abundance in sodium chloride as claimed in claim 1, characterized in that, The fixing members (140) on the first through hole (121) and the second through hole (122) are provided with valves (124).

7. The detection device for chlorine isotope abundance in sodium chloride as claimed in claim 1, characterized in that, The second three-way connector (620) is also connected to a pressure gauge (621).

8. The detection device for chlorine isotope abundance in sodium chloride as claimed in claim 1, characterized in that, The spectrometer (700) is a Fourier transform infrared spectrometer.

9. A method for detecting the isotopic abundance of chlorine in sodium chloride, applied to the detection device according to any one of claims 1 to 8, characterized in that: The steps include: Step S1, placing the NaCl sample to be tested and concentrated sulfuric acid in a first sample tube and a second sample tube respectively, and sealing them; Step S2, open the valve of the nitrogen bottle, adjust the outlet pressure of the pressure regulating valve to 0.3-0.4 MPa, and set the flow rate of the mass flow controller to 100-150 ml / min, respectively purging the water vapor in the reaction container and the spectrometer; Step S3, tilting the reaction container to allow the concentrated sulfuric acid in the second sample tube to flow into the first sample tube to generate HCl, and waiting for the reaction for 10-15 minutes; Step S4, use a sampling needle to extract 1-5 μL of gas from the third through hole, inject it into the first three-way connector and flow it into the spectrometer for detection.

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