A method for isotope separation and enrichment using a multipole rod mass analyzer

Abstract

This invention discloses an isotope separation and enrichment method using a multipole mass analyzer, comprising: injecting a high-concentration solution into a first chamber; ionizing the high-concentration solution in the first chamber using an ICP ion source assembly to form plasma; the plasma vacuum chamber formed in the first chamber then enters an ion extraction system; the extracted ions are introduced into a subsequent multipole mass analyzer; adjusting the voltage applied to the multipole mass analyzer according to the different elements in the sample to be enriched, so that a specific isotope to be separated passes through the multipole mass analyzer and enters a subsequent receiver; this invention can improve the ionization efficiency of existing technologies, reduce the construction cost of the device, and reduce the difficulty of maintenance.

Description

Technical Field

[0001] This invention belongs to the field of analytical testing technology, specifically relating to an isotope separation and enrichment method. Background Technology

[0002] Most elements in the periodic table have multiple isotopes. In modern industry, medicine, biology, and geochemistry, it is necessary to highly enrich specific isotopes of elements. For example, natural nitrogen exists in two isotopes, 235U and 238U, with abundances of 0.7% and 99.3%, respectively. However, nuclear fuel can only use high-purity 235U, so it is necessary to purify and highly enrich the low-abundance 235U found in nature to produce nuclear fuel. Similarly, in the medical field, enriched isotopes are often used to identify metabolic abnormalities. One routine item in physical examinations is Helicobacter pylori infection, which is detected using a carbon-13 urea breath test, utilizing carbon-13 enriched raw materials. Furthermore, in various environmental and chemical analysis fields, isotopes of various metallic and non-metallic elements are frequently used to trace the migration of pollutants or chemical reaction processes; these tracer substances are also highly enriched isotopes.

[0003] There are various types of isotope separation and enrichment techniques. For the enrichment of gaseous isotopes, thermal diffusion or cryogenic distillation methods are generally used; for the enrichment of 235U, gas centrifuges and laser ionization at specific wavelengths can be used; and for isotopes of certain elements, such as 6Li, ion exchange can be used. However, these methods are all specialized and require specialized equipment and methods to achieve the separation and enrichment of specific elements and isotopes. These specialized equipment and methods cannot be applied to the enrichment of other types of isotopes. Therefore, it is necessary to find equipment and methods with a certain degree of versatility.

[0004] The currently available general method for isotope separation and enrichment is electromagnetic separation, and its apparatus is similar to a large magnetic mass spectrometer. The existing technical implementation scheme is a magnetic isotope separation device, the structure and principle diagram of which are shown below. Figure 1 As shown: its key components include an ion source, a sector magnetic field, and an isotope receiving cup. The principle of the ion source is generally solid hot surface ionization or gas electron bombardment ionization. The elements ionized in the ion source are accelerated by an electric field in a high vacuum chamber to form an ion beam that enters the sector magnetic field. Under the magnetic field, they are deflected by the Lorentz effect. Ions with different mass / charge ratios have different deflection radii. By adjusting the magnetic field strength, specific isotopes can be selected and received by the isotope receiving cup after the sector magnetic field.

[0005] The applicant's research and analysis revealed the following drawbacks of existing methods:

[0006] (1) Low ionization efficiency: The ionization efficiency of hot surface ionization is about 1%, while the ionization efficiency of gas electron bombardment is only about 0.01%.

[0007] (2) The construction cost of the equipment suitable for this method is high: Due to the limitation of the ionization efficiency of the ion source, the physical size of the magnetic isotope separation device must be increased to support a sufficiently strong isotope ion beam in order to obtain a sufficient amount of enriched isotopes within a specified time. However, the construction cost of large-scale high-vacuum systems and fan-shaped magnetic fields is extremely expensive. The price of a commercial magnetic mass spectrometer with a radius of 300 mm (the basic principle is the same as that of the magnetic isotope separation device) is several million RMB, and the ion beam current it can support is generally at the level of 10-9 A, which cannot achieve meaningful isotope enrichment. Almost all magnetic isotope separation devices with industrial enrichment capabilities are built with national fiscal appropriations, such as the Calutron device at Oak Ridge National Laboratory in the United States and the Lanzhou Heavy Ion Facility in my country. The construction and operation costs are extremely high, and only special appropriations from the central government can support them.

[0008] (3) The equipment formed by this method is difficult to maintain: Since the large magnetic isotope separation device is a special facility and the ion source is also in the vacuum chamber, it requires professional personnel to operate and maintain it.

[0009] Therefore, it is necessary to find new equipment and new methods to solve the corresponding technical problems. Summary of the Invention

[0010] In view of this, it is necessary to overcome at least one of the aforementioned defects in the prior art. The present invention provides an isotope separation and enrichment method using a multipole mass analyzer, comprising:

[0011] S1. Preprocessing steps:

[0012] A high-concentration solution containing the sample of the element to be enriched is prepared, and the high-concentration solution is converted into aerosol through a nebulizer and introduced into a high-efficiency ion source (ICP).

[0013] S2. Ionization of high-concentration solution of the sample to be enriched

[0014] The high-concentration solution is ionized in the first chamber using an ICP ion source assembly to form plasma, the ICP ion source assembly including a rectangular tube;

[0015] Or isotope collection device.

[0016] In this technical solution, the ICP ion source component uses plasma generated by inductive coupling to ionize a high-concentration solution containing the analyte element, producing ions. These ions enter the ion extraction system within the vacuum chamber through a vacuum interface. The ions generated by the ICP ion source component are then extracted and introduced into a multipole mass analyzer. The multipole mass analyzer is controlled by an electronic control system, allowing a specific isotope to pass through the analyzer while other isotopes are diverted elsewhere. The isotopes that pass through the analyzer are received by a receiver and amplified to form identifiable analytical information. Alternatively, they may be received by an isotope collection device, which removes excess charge, causing the ions to deposit on the surface of the isotope collection device. After collecting sufficient isotopes, the isotope collection device is removed, and the isotopes are extracted using chemical methods, such as acid immersion, to obtain analyzable data.

[0017] This technical solution provides a novel design scheme. By ionizing a high-concentration solution to form an ion source of a certain concentration, and then obtaining a specified isotope through a multipole mass analyzer, it can solve the problems of low ionization efficiency, high construction cost, and difficult operation and maintenance of large-scale magnetic isotope separation devices involved in existing methods. Thus, this method can be used to construct an efficient, low-cost, and universal isotope enrichment device.

[0018] In addition, the isotope separation and enrichment method using a multipole mass analyzer disclosed in this invention has the following additional technical features:

[0019] Furthermore, the receiver is a pluggable receiver used to receive isotopes screened and separated from the multipole mass analyzer.

[0020] Furthermore, the receiver is a Faraday cup, which is detachable and replaceable. After collecting enough isotopes, the Faraday cup is removed and the isotopes are extracted using chemical methods.

[0021] Furthermore, the chemical method is an acid immersion method.

[0022] Furthermore, the Faraday cup is constructed using a cup structure made of elemental graphite or an inert metal material.

[0023] Furthermore, the Faraday cup is grounded.

[0024] Furthermore, the ICP ion source assembly also includes a high-concentration solution container and an inductively coupled component that interacts with the high-concentration solution container to generate plasma.

[0025] Furthermore, the multipole mass analyzer is a quadrupole mass analyzer or a hexapole mass analyzer.

[0026] Furthermore, the vacuum chamber has a vacuum chamber top cover for easy disassembly, installation, and maintenance of the ion extraction system and the multipole mass analyzer.

[0027] Furthermore, the concentration of the high-concentration solution is greater than or equal to 1000 ppm or 0.1 wt%.

[0028] Furthermore, the cone-shaped aperture of the receiver and the vacuum interface and the ion source are on an unobstructed straight line, which is also known as a straight-through ion optical structure.

[0029] Furthermore, employing a short multipole, combined with other structural elements of the device, further enhances ion throughput while simultaneously reducing the device's size and cost. The length of the short multipole can be calculated and determined experimentally based on expected values. The short multipole can be a short quadrupole or a short hexapole, etc.

[0030] Furthermore, the electronic control system includes an ICP radio frequency power supply for exciting the plasma, a quadrupole radio frequency power supply for screening and separating isotopes, and corresponding electronic software, hardware, and firmware control systems for controlling the normal operation of various functional devices, such as vacuum pumps.

[0031] The firmware control system mainly includes: 1. Power distribution module: 220V AC to 12V / 24V / 48V DC power supply. 2. Instrument control module: used to control the vacuum system control module, ICP RF power supply module, quadrupole RF power supply module, signal amplifier module, pneumatic solenoid valve control module, and sensor data readback of each module unit. 3. ICP RF power supply module. 4. Quadrupole RF power supply module. 5. Vacuum system control module. 6. Signal amplifier module. 7. Pneumatic solenoid valve control module: ICP pneumatic circuit control and vacuum interface closure control. 8. Communication module: using Ethernet or fiber optic communication to enable data transmission and analog-to-digital control between the data processing system and the instrument control module.

[0032] Furthermore, the vacuum interface adopts a salt-resistant, large-aperture cone structure. During operation, a high-concentration single-element solution will be introduced; therefore, the quadrupole-based general isotope separation device will employ a salt-resistant design (such as low-cost consumables and a large-aperture cone) in the ICP and vacuum interface sections (corresponding to the sampling and retrieval cones of the multi-pole).

[0033] This method has the following characteristics.

[0034] (1) High ionization efficiency. Ionization is achieved using the ICP principle, and 100% ionization can be achieved for almost all metal elements. Continuous sample injection can be achieved under laboratory conditions without the need to frequently open the vacuum chamber.

[0035] (2) It has good versatility and can achieve enrichment of multiple isotopes. The quadrupole technique can be used to separate and enrich isotopes of all metals from the lightest metal Li to the heaviest metal U.

[0036] (3) The equipment involved in this method has low construction costs. This equipment can be modified based on a commercial quadrupole ICP mass spectrometer. The price of a commercial quadrupole ICP mass spectrometer is currently RMB 500,000 to 1,000,000. Compared with magnetic isotope separation devices, it is extremely economical.

[0037] (4) Simple operation and maintenance. Relevant personnel only need basic training to open the vacuum chamber and replace the Faraday cup.

[0038] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0039] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein:

[0040] Figure 1 This is a schematic diagram illustrating the structural principle of the existing magnetic isotope separation device of the present invention;

[0041] Figure 2 This is a schematic diagram of an embodiment of the isotope separation and enrichment device with a multipole mass analyzer of the present invention.

[0042] Among them, 1. Torch tube 2. Vacuum interface 3. Quadrupole mass analyzer 4. Turbomolecular vacuum pump 5. Plug-in isotope collector 6. Resistance amplifier 7. RF coil 8. Vacuum chamber 9. Sealing ring 10. Removable top cover 11. First chamber 1A. Pre-chamber. Detailed Implementation

[0043] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0044] In the description of this invention, it should be understood that the terms "upper", "lower", "bottom", "top", "front", "back", "inner", "outer", "horizontal", "vertical", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0045] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connection," "connection," "linking," "joining," and "fitting" should be interpreted broadly. For example, they can refer to a fixed connection, an integral connection, or a detachable connection; they can refer to the internal connection of two components; they can refer to a direct connection or an indirect connection through an intermediate medium; "fitting" can refer to the fit between surfaces, or the fit between a point and a surface or a line and a surface, and also includes the fit between a hole and a shaft. For those skilled in the art, the specific meaning of the above terms in this invention can be understood according to the specific circumstances.

[0046] The multi-robot scheduling method for inspection robot and firefighting robot systems of the present invention will now be described with reference to the accompanying drawings, wherein... Figure 1 This is a schematic diagram illustrating the structural principle of the existing magnetic isotope separation device of the present invention; Figure 2 This is a schematic diagram of an embodiment of the isotope separation and enrichment method using a multipole mass analyzer according to the present invention.

[0047] like Figure 2 As shown, according to an embodiment of the present invention, the isotope separation and enrichment method using a multipole mass analyzer includes:

[0048] S1. Preprocessing steps:

[0049] A high-concentration solution containing the sample of the element to be enriched is prepared, and the high-concentration solution is converted into a gas mist through an atomizing device and introduced into a high-efficiency ion source;

[0050] At the same time, a molecular pump is used to evacuate the vacuum chamber, which contains a multipole mass analyzer, a pluggable receiver, and a signal amplification circuit.

[0051] S2. Ionization of high-concentration solution of the sample to be enriched

[0052] The high-concentration solution is ionized in the first chamber using an ICP ion source assembly to form plasma, the ICP ion source assembly including a rectangular tube;

[0053] S3. Ion splitting in the vacuum chamber

[0054] The ions formed in the first chamber in S2 enter the vacuum chamber through the vacuum interface between the first chamber and the vacuum chamber, and then enter the ion extraction system. The extracted ions are introduced into the subsequent multipole mass analyzer. The voltage applied to the multipole mass analyzer is adjusted according to the different elements in the sample to be enriched, so that the required isotopes can pass through the multipole mass analyzer and enter the subsequent receiver.

[0055] In addition, the isotope separation and enrichment method using a multipole mass analyzer disclosed in this invention also has the following additional technical features:

[0056] According to some embodiments of the present invention, the receiver is a pluggable receiver for receiving isotopes screened and separated from the multipole mass analyzer.

[0057] According to some embodiments of the present invention, the receiver is a Faraday cup, which is detachable and replaceable. After collecting sufficient isotopes, the Faraday cup is removed and the isotopes are extracted by chemical methods.

[0058] Furthermore, the chemical method is an acid immersion method.

[0059] Furthermore, the Faraday cup is constructed using a cup structure made of elemental graphite or an inert metal material.

[0060] Furthermore, the Faraday cup is grounded.

[0061] According to an embodiment of the present invention, the ICP ion source assembly further includes a high-concentration solution container and an inductively coupled component that interacts with the high-concentration solution container to generate plasma.

[0062] According to some embodiments of the present invention, the multipole mass analyzer is a quadrupole mass analyzer or a hexapole mass analyzer.

[0063] According to an embodiment of the present invention, the vacuum chamber has a top cover for convenient disassembly, installation, and maintenance of the ion extraction system and the multipole mass analyzer. The top cover can be easily removed for maintenance of the ion extraction system and the quadrupole, as well as for replacing the Faraday cup to collect isotopes.

[0064] The control function devices include electronic software, hardware, and firmware control systems for the normal operation of units such as vacuum pumps.

[0065] According to an embodiment of the present invention, the concentration of the high-concentration solution is greater than or equal to 1000 ppm or 0.1 wt%.

[0066] According to an embodiment of the present invention, the cone aperture of the receiver and the vacuum interface and the ion source are on an unobstructed straight line, which is also a straight-through ion optical structure.

[0067] Furthermore, employing a short multipole, combined with other structural elements of the device, further enhances ion throughput while simultaneously reducing the device's size and cost. The length of the short multipole can be calculated and determined experimentally based on expected values. The short multipole can be a short quadrupole or a short hexapole, etc.

[0068] According to an embodiment of the present invention, the electronic control system includes an ICP radio frequency power supply for exciting plasma, a quadrupole radio frequency power supply for screening and separating isotopes, and corresponding electronic software, hardware and firmware control systems for controlling the normal operation of various functional devices, such as vacuum pumps.

[0069] The firmware control system mainly includes: 1. Power distribution module: 220V AC to 12V / 24V / 48V DC power supply. 2. Instrument control module: used to control the vacuum system control module, ICP RF power supply module, quadrupole RF power supply module, signal amplifier module, pneumatic solenoid valve control module, and sensor data readback of each module unit. 3. ICP RF power supply module. 4. Quadrupole RF power supply module. 5. Vacuum system control module. 6. Signal amplifier module. 7. Pneumatic solenoid valve control module: ICP pneumatic circuit control and vacuum interface closure control. 8. Communication module: using Ethernet or fiber optic communication to enable data transmission and analog-to-digital control between the data processing system and the instrument control module.

[0070] According to an embodiment of the present invention, the vacuum interface adopts a salt-resistant, large-aperture cone structure. During operation, a high-concentration single-element solution will be introduced; therefore, the quadrupole-based general isotope separation device will employ a salt-resistant design (such as low-cost consumables and a large-aperture cone) in the ICP and vacuum interface sections (corresponding to the sampling and retrieval cones of the multi-pole).

[0071] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

[0072] Any reference to "an embodiment," "embodiment," "illustrative embodiment," etc., means that the specific component, structure, or feature described in connection with that embodiment is included in at least one embodiment of the present invention. Such illustrative expressions throughout this specification do not necessarily refer to the same embodiment. Furthermore, when a specific component, structure, or feature is described in connection with any embodiment, it is claimed that implementing such a component, structure, or feature in connection with other embodiments falls within the scope of those skilled in the art.

[0073] Although specific embodiments of the invention have been described in detail with reference to several illustrative examples, it should be understood that those skilled in the art can devise various other modifications and embodiments that fall within the spirit and scope of the invention. Specifically, reasonable variations and modifications can be made to the arrangement of components and / or dependent combinations within the scope of the foregoing disclosure, drawings, and claims without departing from the spirit of the invention. The scope of these variations and modifications, apart from those concerning components and / or layout, is defined by the appended claims and their equivalents.

Claims

1. An isotope separation and enrichment method using a multipole mass analyzer, characterized in that... ,include, S1. Preprocessing steps: A high-concentration solution containing the sample of the element to be enriched is prepared, and the high-concentration solution is converted into a gas mist through an atomizing device and introduced into a high-efficiency ion source; S2. Ionization of high-concentration solution of the sample to be enriched The high-concentration solution is ionized in the first chamber using an ICP ion source assembly to form plasma. The ICP ion source assembly includes a rectangular tube, a high-concentration solution container, and an inductively coupled component that interacts with the high-concentration solution container to generate plasma. S3. Ion splitting in the vacuum chamber The plasma formed in the first chamber in S2 enters the vacuum chamber through the vacuum interface between the first chamber and the vacuum chamber, and then enters the ion extraction system. The extracted ions are introduced into the subsequent multipole mass analyzer. The voltage applied to the multipole mass analyzer is adjusted according to the different elements in the sample to be enriched, so that the isotopes to be separated pass through the multipole mass analyzer and enter the subsequent receiver. The receiver is a pluggable receiver used to receive isotopes screened and separated from the multipole mass analyzer, or the receiver is a Faraday cup that is detachable and replaceable. After collecting enough isotopes, the Faraday cup is removed and the isotopes are extracted by chemical methods. The concentration of the high-concentration solution is greater than or equal to 1000 ppm or greater than or equal to 0.1 wt%.

2. The isotope separation and enrichment method using a multipole mass analyzer according to claim 1, characterized in that, The chemical method is acid immersion.

3. The isotope separation and enrichment method using a multipole mass analyzer according to claim 1, characterized in that, The Faraday cup is constructed using a cup structure made of elemental graphite or an inert metal.

4. The isotope separation and enrichment method using a multipole mass analyzer according to claim 1, characterized in that, The Faraday cup is grounded.

5. The isotope separation and enrichment method using a multipole mass analyzer according to claim 1, characterized in that, The multipole mass analyzer is a quadrupole mass analyzer or a hexapole mass analyzer.

6. The isotope separation and enrichment method using a multipole mass analyzer according to claim 1, characterized in that, The vacuum chamber has a top cover for easy disassembly, installation, and maintenance of the ion extraction system and the multipole mass analyzer.

7. The isotope separation and enrichment method using a multipole mass analyzer according to claim 1, characterized in that, The receiver and the cone-shaped aperture of the vacuum interface are aligned with the ion source in an unobstructed straight line.

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