Apparatus for rapid determination of selenium

Abstract

The utility model discloses equipment for rapidly measuring selenium, which relates to the technical field of selenium measurement and comprises an electric heating evaporation mechanism, a gas-phase substance secondary decomposition mechanism, a temperature control area, a gas-phase enrichment mechanism, an ignition mechanism and an atomization mechanism formed by the ignition mechanism and the gas-phase enrichment mechanism together, in the implementation process, the electric heating evaporation mechanism and the gas-phase substance secondary decomposition mechanism are matched with each other to directly evaporate selenium in a sample in an electric heating manner, so that the pretreatment process of a complex sample is avoided, and a solid sample or a liquid sample can be directly analyzed; the arranged atomization mechanism effectively separates a complex matrix of a sample product in the electric heating evaporation process by utilizing the characteristics that gold captures selenium oxide and selenium atoms, and the precision of sample testing is ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of selenium determination, in particular to a device for rapid selenium determination. Background Art

[0002] For example, the selenium content of most dietary foods is often less than 0.03 mg / kg. However, accurately measuring selenium levels below this concentration is crucial for a balanced diet. To improve the sensitivity of selenium detection, two papers, 1 (Journal of Analytical Atomic Spectrometry, 2001, 16, 1414–1419) and 2 (Spectrochimica Acta Part B, 2009, 63, 956–960), reported the low-temperature capture and high-temperature release of selenium hydride (HSe) with gold, thallium, or gold-coated tungsten wires. This gas-phase enrichment of HSe enabled highly sensitive detection of selenium in solutions at the ng / L level. Unfortunately, these methods still only allow for the detection of selenium in solutions, and the tedious sample pretreatment steps of converting the sample into a solution or ensuring that the selenium in the sample is evenly dispersed in the solution remain unchanged. Furthermore, all of these analytical methods require high-pressure noble gases such as argon. Utility Model Content

[0003] In order to solve the above technical problems, the utility model provides a device and a method for quickly determining selenium.

[0004] In order to achieve the above-mentioned purpose, the technical solution adopted by the present utility model is as follows:

[0005] Provided is a device for rapid selenium determination, comprising a first reaction tube and a second reaction tube made of quartz. The second reaction tube is provided with a first electric heater and a second electric heater in sequence from a sample injection end to a sample discharge end. The first electric heater and the second reaction tube form an electric evaporation mechanism. An auxiliary decomposition component is provided in the second reaction tube at a position corresponding to the second electric heater. The auxiliary decomposition component, the second electric heater, and the second reaction tube together form a gaseous secondary decomposition mechanism. The electric evaporation mechanism and the gaseous secondary decomposition mechanism cooperate with each other to directly evaporate selenium in the sample.

[0006] The sample discharge end of the second reaction tube is connected to the sample injection end of the first reaction tube to form an "I"-shaped detection pipeline. The sample discharge end of the first reaction tube serves as the detection end of the detection pipeline. A third electric heater is provided on the outer peripheral side of the first reaction tube and located between the sample discharge ends to form a temperature control area. A gold capture body is filled in the first reaction tube and located in the temperature control area to form a gas phase enrichment mechanism. The detection end of the detection pipeline is provided with an ignition mechanism. The ignition mechanism and the gas phase enrichment mechanism together form an atomization mechanism. The characteristics of gold capturing selenium oxide and selenium atoms are utilized to effectively separate the complex matrix of the sample product in the electrothermal evaporation process through the setting of the gold capture body, thereby ensuring the precision of the sample test.

[0007] Preferably, the auxiliary decomposition member is porous quartz, quartz sand or quartz wool.

[0008] Preferably, the gold capturing body is a gold-plated quartz sand layer or a gold wire mesh.

[0009] The method for using the above-mentioned device for rapid determination of selenium comprises the following steps:

[0010] S1: The sample is placed in the electric evaporation mechanism of the detection pipeline through the sample injection mechanism to heat it so that selenium is released by thermal decomposition. The undecomposed organic matter is heated again by the gas phase secondary decomposition mechanism to release selenium by thermal decomposition.

[0011] S2: The carrier gas carries the pyrolyzed selenium, which is atomized by the atomization mechanism and then discharged from the detection end of the detection pipeline;

[0012] S3: Use a detection mechanism to measure the concentration of selenium atoms at the detection end of the detection pipeline. This concentration is the concentration of selenium atoms in the sample.

[0013] The steps for atomizing selenium by the above-mentioned atomization mechanism are as follows:

[0014] S2.1: The carrier gas carries the pyrolyzed selenium into the temperature-controlled area and is captured by the gold-coated quartz sand layer to achieve gas phase enrichment;

[0015] S2.2: The temperature-controlled area heats the gold-plated quartz sand layer to release selenium again and carry it to the ignition mechanism by the carrier gas to ignite and atomize.

[0016] Preferably, the temperature of the temperature control area during the gas phase enrichment process is 200°C to 500°C, and the temperature at which the gold capture body releases selenium is 900°C to 1000°C.

[0017] Preferably, the carrier gas is air, oxygen, nitrogen, argon, helium, hydrogen or a mixture thereof.

[0018] Preferably, the detection mechanism is a dispersive atomic fluorescence detector or a dual-light source adjacent line corrected atomic absorption detector or an atomic emission spectrometer or an atomic emission spectrometer.

[0019] Preferably, the sample introduction mechanism includes a sample crucible and a manipulator for placing the sample crucible on the electrothermal evaporation mechanism.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. Through the cooperation of the electrothermal evaporation mechanism and the gas phase secondary decomposition mechanism, the selenium in the sample can be directly evaporated, thereby eliminating the complicated sample pre-treatment process and directly analyzing solid or liquid samples;

[0022] 2. The atomization mechanism uses the characteristics of gold capturing selenium oxide and selenium atoms to effectively separate the complex matrix of the sample product in the electrothermal evaporation process, ensuring the precision of the sample test. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0024] Figure 2 It is a schematic diagram of the sample analysis process.

[0025] Figure identification: 1. first reaction tube, 2. second reaction tube, 3. first electric heater, 4. second electric heater, 5. auxiliary decomposition component, 6. third electric heater, 7. gold capture body, 8. ignition mechanism, 9. sample crucible. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments and drawings. The schematic implementation methods of the present invention and their descriptions are only used to explain the present invention and are not intended to limit the present invention.

[0027] Example 1

[0028] A device for rapid determination of selenium, e.g. Figure 1As shown, it includes a first reaction tube 1 and a second reaction tube 2 made of quartz. The second reaction tube 2 is provided with a first electric heater 3 and a second electric heater 4 in sequence from the injection end to the discharge end. The first electric heater 3 and the second reaction tube 2 form an electric evaporation mechanism. An auxiliary decomposition member 5 is provided in the second reaction tube 2 and at a position corresponding to the second electric heater 4. The auxiliary decomposition member 5, the second electric heater 4 and the second reaction tube 2 together form a gas phase secondary decomposition mechanism. The auxiliary decomposition member 5 is porous quartz, quartz sand or quartz wool. The discharge end of the second reaction tube 2 is provided with a first electric heater 3 and a second electric heater 4. It is connected to the sampling end of the first reaction tube 1 to form an "I"-shaped detection pipeline. The sampling end of the first reaction tube 1 serves as the detection end of the detection pipeline. A third electric heater 6 is provided on the outer peripheral side of the first reaction tube 1 and between the sampling ends to form a temperature control area. A gold capture body 7 is filled in the first reaction tube 1 and located in the temperature control area to form a gas phase enrichment mechanism. The gold capture body 7 is a gold-plated quartz sand layer or a gold wire mesh. An ignition mechanism 8 is provided at the detection end of the detection pipeline. The ignition mechanism 8 and the gas phase enrichment mechanism together form an atomization mechanism.

[0029] like Figure 2 As shown, the steps of the above-mentioned device for rapid determination of selenium are as follows:

[0030] S1: The sample is placed in the electric evaporation mechanism of the detection pipeline through the sample injection mechanism to heat it to release selenium by thermal decomposition. The undecomposed organic matter is heated again by the gas phase secondary decomposition mechanism to release selenium by thermal decomposition. The selenium in the sample can be directly evaporated by electric heating, thereby eliminating the complicated sample pre-treatment process and directly analyzing solid or liquid samples;

[0031] S2: The carrier gas carries the pyrolyzed selenium, which is atomized by the atomization mechanism and then discharged from the detection end of the detection pipeline;

[0032] S3: Use a detection mechanism to measure the concentration of selenium atoms at the detection end of the detection pipeline. This concentration is the concentration of selenium atoms in the sample.

[0033] The steps for atomizing selenium by the atomization mechanism are as follows:

[0034] S2.1: The carrier gas carries the pyrolyzed selenium into the temperature-controlled area and is captured by the gold capture element 7 to achieve gas-phase enrichment;

[0035] S2.2: The temperature-controlled area heats the gold capture body 7 to release selenium again and carry it to the ignition mechanism 8 by the carrier gas to ignite and atomize it. This process utilizes the characteristics of gold capturing selenium oxide and selenium atoms to effectively separate the complex matrix of the sample product in the electrothermal evaporation process, ensuring the precision of the sample test.

[0036] The above-mentioned detection mechanism is a dispersive atomic fluorescence detector or a dual-light source adjacent line corrected atomic absorption detector. The sampling mechanism includes a sample crucible 9 and a manipulator for placing the sample crucible 9 on the electrothermal evaporation mechanism. The carrier gas is air, oxygen, nitrogen, argon, helium, hydrogen or a mixture thereof.

[0037] The temperature of the temperature control area during the gas phase enrichment process is 200°C to 500°C, and the temperature at which the gold capture body 7 releases selenium is 900°C to 1000°C.

[0038] When implementing:

[0039] The analysis method process of samples with high organic matter content such as grain and meat is as follows: Sample S is placed in an electric evaporation mechanism. During the continuous injection of carrier gas A, the electric evaporation mechanism heats the sample S, and selenium in the sample is thermally decomposed and released. The organic matter that is not fully decomposed is subjected to secondary high-temperature decomposition by the gas phase secondary decomposition mechanism. Gas A continues to carry the selenium released by thermal decomposition in the sample to the temperature control area with a temperature of 200°C to 500°C. The selenium is captured by the gold capture body 7, and then the temperature control area is heated to 1000°C to 1000°C. Selenium is decomposed and released from the gold capture body 7 and carried by gas A to the flame F for atomization. The concentration of selenium is detected by the detection mechanism, where gas A is air.

[0040] The analysis method process for soil, water, mineral samples, etc.: the sample is placed in an electric thermal evaporation mechanism, and a carrier gas is continuously injected into the second reaction tube 2. During this process, the selenium in the sample is heated and decomposed by the electric thermal evaporation mechanism and the gas phase secondary decomposition mechanism. The carrier gas injected into the second reaction tube 2 is hydrogen. The hydrogen carries the thermally decomposed selenium to the temperature control area with a temperature of 200°C to 500°C. The selenium is captured by the gold capture body 7. Then the temperature control area is heated to 1000°C to 1000°C. The selenium is decomposed from the gold capture body 7 and carried by the hydrogen to the flame F for atomization. The concentration of selenium is detected by the detection mechanism.

[0041] Capture mechanism: Using air or high-purity oxygen as the carrier gas, the selenium evaporated by electrothermal heating is selenium oxide, which can be captured by gold.

[0042] The air is generated by a membrane air pump, supplied by a compressor, or provided by cylinder gas. The hydrogen is obtained by electrolyzing water, supplied by cylinder gas, or released by hydrogen storage materials.

[0043] Of course, the present invention may have many other implementation methods. Without departing from the spirit and essence of the present invention, technicians familiar with the field may make various corresponding changes and deformations based on the present invention, but these corresponding changes and deformations should all fall within the scope of protection of the claims attached to the present invention.

Claims

1. A device for rapid determination of selenium, characterized in that: The invention comprises a first reaction tube (1) and a second reaction tube (2) made of quartz, wherein the second reaction tube (2) is provided with a first electric heater (3) and a second electric heater (4) in sequence from the sample injection end to the sample discharge end, the first electric heater (3) and the second reaction tube (2) form an electric evaporation mechanism, an auxiliary decomposition component (5) is provided in the second reaction tube (2) at a position corresponding to the second electric heater (4), and the auxiliary decomposition component (5), the second electric heater (4) and the second reaction tube (2) together form a gas phase secondary decomposition mechanism; The sample discharge end of the second reaction tube (2) is connected to the sample injection end of the first reaction tube (1) to form a "I"-shaped detection pipeline. The sample discharge end of the first reaction tube (1) serves as the detection end of the detection pipeline. A third electric heater (6) is provided on the outer peripheral side of the first reaction tube (1) and located between the sample discharge ends to form a temperature control area. A gold capture body (7) is filled in the first reaction tube (1) and located in the temperature control area to form a gas phase enrichment mechanism. An ignition mechanism (8) is provided at the detection end of the detection pipeline. The ignition mechanism (8) and the gas phase enrichment mechanism together form an atomization mechanism.

2. The device for rapid determination of selenium according to claim 1, characterized in that The auxiliary decomposition component (5) is porous quartz, quartz sand or quartz wool.

3. The device for rapid determination of selenium according to claim 1, characterized in that The gold capturing body (7) is a gold-plated quartz sand layer or a gold wire mesh.

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