Aerosol acceleration device, applications and icp-ms detection method

Abstract

The present application relates to the technical field of material analysis, in particular to an aerosol accelerating device, application and ICP-MS detection method.The ICP-MS solid sample feeding device or ICP-MS solid sample feeding system provided by the present application can realize the idea of increasing the moving speed of aerosol by only adding an aerosol accelerating device between the ablation chamber and the ionization chamber, and the operation is simple, and the energy loss and time cost can be effectively reduced.Meanwhile, the interference of matrix effect is reduced by solid sample feeding, the sample ionization degree is higher by using the accelerating device, and the interference of mass effect and RSD is effectively reduced.

Description

Technical Field

[0001] This invention relates to the field of materials analysis technology, and in particular to aerosol acceleration devices, their applications, and ICP-MS detection methods. Background Technology

[0002] Since its invention in the 1980s, inductively coupled plasma mass spectrometry (ICP-MS) has been widely used in geology, biology, medicine, agriculture, food, materials, and other fields due to its excellent detection capabilities for ultra-trace elements. Especially in the detection of rare earth elements, ICP-MS is gradually becoming the most promising detection method for trace and ultra-trace rare earth analysis.

[0003] Inductively coupled plasma mass spectrometry (ICP-MS), sample introduction methods can be categorized into solid-state, liquid-state, and gas-state methods. Solid-state introduction methods include laser ablation, spark ablation, electrothermal evaporation, and suspension-state introduction. The basic principle of solid-state introduction is to use heat to raise the temperature of the solid sample surface, causing it to vaporize. Argon or hydrogen is used as the carrier gas to deliver the aerosol generated from the solid sample to the ionization chamber for ionization. The mass spectrometer then filters the ionized sample, utilizing the fact that ions with different mass-to-charge ratios arrive at the receiver at different times to distinguish different elements.

[0004] While existing solid sample introduction methods can achieve sample introduction and effectively reduce matrix interference on element detection, they have a fatal drawback: during the ionization process of the aerosol generated by the sample being transported to the ionization chamber by the carrier gas, the sample aerosol moves slowly, resulting in insufficient ionization and causing serious mass interference, leading to a decrease in detection accuracy and signal fluctuations. If the carrier gas flow rate is increased to speed up the sample aerosol movement, matrix interference will also occur, which will also lead to a decrease in detection accuracy.

[0005] In view of this, the present invention is proposed. Summary of the Invention

[0006] The purpose of this invention is to provide an aerosol acceleration device that, when installed in an ICP-MS solid sample introduction device or ICP-MS solid sample introduction system, can improve the flow rate and ionization of sample aerosols while avoiding matrix interference.

[0007] To solve the above-mentioned technical problems and achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0008] In a first aspect, the present invention provides an aerosol acceleration device, which includes, in sequence along the aerosol flow direction, a filter assembly and an acceleration tube array.

[0009] In an optional embodiment, the filtration assembly includes a filter screen or a filter membrane.

[0010] In an optional embodiment, the filter screen or filter membrane has a pore size (or mesh count) of 300 mesh.

[0011] In an optional embodiment, the accelerating tube array is respectively hermetically connected to a first sealing end and a second sealing end along the aerosol flow direction. The first sealing end is connected to the front cylinder, and the second sealing end is connected to the rear cylinder. The filter assembly is disposed in the front cylinder.

[0012] In an optional embodiment, the accelerating tube array is disposed inside the accelerating cylinder, with sealing plates connected to both ends. The two ends of the accelerating cylinder are connected to the front cylinder and the rear cylinder, respectively, and the filter assembly is disposed inside the front cylinder.

[0013] In an optional embodiment, a constant temperature protective sleeve is provided outside the front cylinder.

[0014] Secondly, the present invention provides an ICP-MS solid sample introduction device, which includes a gas supply device connected by a pipeline, a sample ablation chamber, and an ionization chamber; an aerosol accelerator as described in any of the foregoing embodiments is installed on the pipeline connecting the sample ablation chamber and the ionization chamber, the front cylinder and the rear cylinder of the aerosol accelerator are connected to the pipeline through a detachable sleeve, and the ratio of the distance of the aerosol accelerator from the sample ablation chamber to the distance of the aerosol accelerator from the ionization chamber is 20:1.

[0015] Thirdly, the present invention provides an ICP-MS solid sample introduction system, which includes the ICP-MS solid sample introduction device described in the foregoing embodiments and a control system for adjusting specific parameters of the ICP-MS solid sample introduction device; the specific parameters include the gas flow rate in the gas supply device, the temperature in the sample ablation chamber, the gas pressure in the sample ablation chamber, the ablation current, and the voltage.

[0016] Fourthly, the present invention provides the application of the aerosol acceleration device, the ICP-MS solid sample introduction device, or the ICP-MS solid sample introduction system described in any of the foregoing embodiments in ICP-MS detection.

[0017] Fifthly, the present invention provides an ICP-MS detection method in which the solid sample to be tested is placed in the sample ablation chamber of the ICP-MS solid sample introduction device or the ICP-MS solid sample introduction system described in the aforementioned embodiments. The aerosol obtained by heating is filtered and accelerated by the aerosol acceleration device and then enters the ionization chamber for ionization. Then, the mass spectrometer separates each element in the solid sample to be tested and detects it by ICP in sequence.

[0018] The ICP-MS detection method includes the step of replacing the aerosol accelerator or the front cylinder.

[0019] The ICP-MS solid sample introduction device or ICP-MS solid sample introduction system provided by this invention, compared with traditional sample introduction devices, only requires the addition of an aerosol accelerator between the ablation chamber and the ionization chamber to achieve the goal of increasing the aerosol migration rate. This simplifies operation and effectively reduces energy consumption and time costs. Simultaneously, solid sample introduction reduces matrix effect interference, and the use of an accelerator results in higher sample ionization, effectively reducing mass effect interference and RSD. Attached Figure Description

[0020] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the ICP-MS solid sample introduction system provided in Embodiment 1 of the present invention;

[0022] Figure 2 This is a schematic diagram of the structure of the first aerosol acceleration device 24 provided in Embodiment 1 of the present invention;

[0023] Figure 3 This is a schematic diagram of the structure of the second aerosol acceleration device 25 provided in Embodiment 1 of the present invention;

[0024] Figure 4 This is a schematic diagram of the structure of the third aerosol acceleration device 26 provided in Embodiment 1 of the present invention. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0026] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0027] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0028] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use. For example, the aerosol flow direction described in this invention is only for the convenience of describing the invention and simplifying the description, and does 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, and therefore should not be construed as a limitation of the invention. In addition, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0029] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0030] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0031] Example 1

[0032] This invention provides an ICP-MS solid sample introduction system, such as... Figure 1 As shown below. (Combined with...) Figure 1 The sample introduction system is described in detail.

[0033] like Figure 1 As shown, the ICP-MS solid sample introduction system provided by the present invention consists of a control system 1 and an ICP-MS solid sample introduction device 2. The ICP-MS solid sample introduction device 2 includes a gas supply device 21, a sample ablation chamber 22 and an ionization chamber 23. A first aerosol acceleration device 24 is installed on the pipe connecting the sample ablation chamber 22 and the ionization chamber 23.

[0034] The structure of the aerosol acceleration device 24 is as follows: Figure 2As shown, the aerosol accelerator 24 includes a filter assembly 243 and an accelerating tube array 246 sequentially along the aerosol flow direction. The aerosol flows from left to right, i.e., it first passes through the filter assembly 243 and then through the accelerating tube array 246. The accelerating tube array 246 is sealed at both ends by a first sealing end 244 and a second sealing end 247 via sealing rings 245. The first sealing end 244 is connected to the front cylinder 242, and the second sealing end is connected to the rear cylinder 248. The filter assembly 243 is disposed inside the front cylinder 242. The front cylinder 242 and the rear cylinder 248 are connected to a pipe connecting the sample ablation chamber 22 and the ionization chamber 23 via a detachable sleeve 241. The ratio of the distance of the aerosol accelerator from the sample ablation chamber to the distance of the aerosol accelerator from the ionization chamber is 20:1.

[0035] The filter assembly 243 uses a filter membrane with a pore size of 300 mesh.

[0036] Combination Figure 1 and Figure 2 The specific workflow of this embodiment is described as follows: The solid sample on the sample stage 221 is turned into an aerosol in the ablation chamber 22 by the control system 1 through laser ablation, spark ablation or electrothermal evaporation. Then, a hydrogen-argon mixture of 2% to 4% (v / v) H2 is used as the carrier gas and the aerosol is sent to the ionization chamber 23 through the gas supply device 21. During the flow of the aerogel, it is filtered and accelerated by the aerosol acceleration device 24.

[0037] The sleeve 241 allows the front cylinder 242 and the rear cylinder 242 to be detachably installed on the pipeline, while also ensuring the airtightness of the pipeline connection. The filter membrane is installed inside the front cylinder 242 and is welded to the front cylinder 242. It is used to filter large solid particles in the sample aerosol, preventing blockage of the acceleration tube. At the same time, the filter membrane and the front cylinder 242 can be disassembled and replaced as separate modules.

[0038] In summary, during use, the sample aerosol is significantly accelerated by the accelerating tube array 246. To prevent clogging, a filter membrane is installed before the accelerating tube array 246 to filter out large solid particles in the sample aerosol, thus preventing blockage. After acceleration by the accelerating tube array 246, the sample can collide with the auxiliary gas at extremely high speeds in the ionization chamber to generate plasma, improving plasma yield and ionization degree. Therefore, it can effectively improve plasma utilization, reduce signal fluctuations and relative standard deviation in mass spectrometry, weaken the influence of mass effects, and greatly improve the detection accuracy of inductively coupled plasma mass spectrometry.

[0039] Example 2

[0040] This embodiment provides another ICP-MS solid sample introduction system, which differs from Embodiment 1 only in that a second aerosol accelerator 25 is installed on the pipe connecting the sample ablation chamber 22 and the ionization chamber 23. Figure 3 As shown.

[0041] The second aerosol acceleration device 25 includes a front cylinder 242, an acceleration cylinder 251 and a rear cylinder 248 connected in sequence. The acceleration cylinder 251 is provided with an acceleration tube array 246 with sealing plates 252 at both ends. Meanwhile, a filter membrane 243 is welded inside the front cylinder 242.

[0042] The workflow of this ICP-MS solid sample introduction system is the same as that in Example 1, and will not be repeated here.

[0043] Example 3

[0044] This embodiment 1 provides a third type of ICP-MS solid sample introduction system. The only difference from embodiment 1 is that a third aerosol acceleration device 26 is installed on the pipe connecting the sample ablation chamber 22 and the ionization chamber 23. Figure 4 As shown, the third aerosol accelerator 26 and the first aerosol accelerator 24 in Example 1 are only separated by a constant temperature protective sleeve 261 on the front cylinder 242. By setting the temperature to 800°C, the large aerosol particles being filtered are always in a gaseous state and roll in the front cylinder 242 with the airflow, thus avoiding clogging of the filter membrane due to the aggregation of large aerosol particles.

[0045] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An ICP-MS solid sample introduction device, characterized in that, The ICP-MS solid sample introduction device includes a gas supply device connected by pipeline, a sample ablation chamber, and an ionization chamber. An aerosol accelerator is installed on the pipeline connecting the sample ablation chamber and the ionization chamber. The front and rear cylinders of the aerosol accelerator are connected to the pipeline through a detachable sleeve. The aerosol accelerator includes a filter assembly and an accelerating tube array in sequence along the aerosol flow direction. The accelerating tube array is respectively sealed with a first sealing end and a second sealing end along the aerosol flow direction. The accelerating tube array includes multiple accelerating tubes. The aerosol is accelerated by the accelerating tube array. The first sealing end is connected to the front cylinder, and the second sealing end is connected to the rear cylinder. A constant temperature protective sleeve is provided outside the front cylinder.

2. The ICP-MS solid sample introduction device according to claim 1, characterized in that, The filtration assembly includes a filter screen or a filter membrane.

3. The ICP-MS solid sample introduction device according to claim 2, characterized in that, The filter screen or filter membrane has a mesh size of 300.

4. The ICP-MS solid sample introduction device according to claim 1, characterized in that, The filter assembly is located inside the front cylinder.

5. The ICP-MS solid sample introduction device according to claim 1, characterized in that, The acceleration tube array is disposed inside the acceleration cylinder, with sealing plates connected to both ends. The two ends of the acceleration cylinder are connected to the front cylinder and the rear cylinder, respectively. The filter assembly is disposed inside the front cylinder.

6. The ICP-MS solid sample introduction device according to claim 1, characterized in that, The temperature setting of the constant temperature protective sleeve is 800℃.

7. The ICP-MS solid sample introduction device according to claim 1, characterized in that, The ratio of the distance between the aerosol accelerator and the sample ablation chamber to the distance between the aerosol accelerator and the ionization chamber is 20:

1.

8. An ICP-MS solid sample introduction system, characterized in that, The ICP-MS solid sample introduction system includes the ICP-MS solid sample introduction device as described in any one of claims 1-7 and a control system for adjusting specific parameters of the ICP-MS solid sample introduction device; the specific parameters include the gas flow rate in the gas supply device, the temperature in the sample ablation chamber, the gas pressure in the sample ablation chamber, the ablation current, and the voltage.

9. The application of the ICP-MS solid sample introduction device according to any one of claims 1-7 or the ICP-MS solid sample introduction system according to claim 8 in ICP-MS detection.

10. An ICP-MS detection method, characterized in that, The solid sample to be tested is placed in the sample ablation chamber of the ICP-MS solid sample introduction device according to any one of claims 1-7 or the ICP-MS solid sample introduction system according to claim 8. The aerosol obtained by heating is filtered and accelerated by the aerosol acceleration device and then ionized in the ionization chamber. Then, the mass spectrometer separates each element in the solid sample to be tested and detects them sequentially by ICP. The ICP-MS detection method includes the step of replacing the aerosol acceleration device or the front cylinder.

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