Helium isothermal adsorption measurement method based on magnetic suspension balance

Abstract

The application discloses a helium isothermal adsorption calculation method based on a magnetic suspension balance. A sample cabin of a magnetic suspension balance for storing a sample is vacuumized for a preset time at a preset temperature, and a first mass of the sample is obtained after the temperature of the sample cabin in an indoor environment; a second mass and a volume of a sample frame are obtained, a plurality of adsorption temperature points are set, readings of the magnetic suspension balance corresponding to different adsorption pressure points at each adsorption temperature point and free-phase helium density in the sample cabin are obtained; a linear relationship diagram of each adsorption temperature point is drawn according to the readings and the free-phase helium density, and a slope is calculated; a unit mass skeleton volume of the sample is obtained by fitting the plurality of adsorption temperature points, the slope, the first mass, the volume and an ideal gas constant; and the helium adsorption amount is calculated in combination with the first mass, the second mass, the volume, the readings, the free-phase helium density and the atomic mass of helium, a helium isothermal adsorption curve of each adsorption temperature point is drawn, and fitting is performed to obtain a Langmuir maximum adsorption amount and a Langmuir pressure.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of molecular simulation, and relates to a helium isothermal adsorption calculation method based on a magnetic suspension balance. BACKGROUND

[0002] Helium is one of the gases with the lowest adsorption capacity in nature due to its single-atom structure, small atomic radius and low polarizability. At present, in the evaluation of shale gas and coalbed methane resources and the research of carbon dioxide storage, researchers usually carry out isothermal adsorption experiments on coal rocks and organic-rich shale based on the assumption that helium has no adsorption capacity, and determine the adsorption capacity of methane and carbon dioxide to evaluate the resource quantity of shale gas and coalbed methane or the carbon dioxide storage capacity. Although the interaction force (such as van der Waals force) between helium and other molecules is very weak, it is not completely zero, and theoretically, helium has adsorption capacity, and its adsorption capacity will be significantly improved under high pressure. This has been confirmed by molecular simulation research. Therefore, the traditional isothermal adsorption experimental method based on the assumption that helium has no adsorption capacity inevitably has defects in accuracy, and it is of great significance to establish an accurate helium adsorption calculation method for the evaluation of shale gas and coalbed methane resources and the evaluation of carbon dioxide storage effect.

[0003] In addition, helium is widely used in the fields of semiconductors and national defense due to its special physical properties, and is a national scarce strategic resource. It is an urgent national demand to establish a helium accumulation theory suitable for the geological conditions of China, promote the further development of helium exploration and improve the self-sufficiency degree of helium resources. At present, all the helium resources for industrial use come from the exploitation of underground helium-rich natural gas, and it is also of great significance to establish an accurate helium adsorption calculation method to evaluate the adsorption characteristics of helium under high pressure conditions, to identify the occurrence state and migration and enrichment mechanism of helium in the formation, and to perfect the helium accumulation theory of China.

[0004] In related technologies, the volume method, the weight method and the breakthrough curve method are used to simulate the adsorption behavior of helium. However, the above three traditional isothermal adsorption experimental methods all use the assumption that helium has no adsorption capacity to calculate the key parameters in the experiment, and the testing principle determines that they cannot determine the adsorption characteristics of helium.

[0005] Therefore, how to more deeply, accurately and effectively determine the adsorption capacity of helium has become a problem to be solved. SUMMARY

[0006] Therefore, the helium isothermal adsorption calculation method based on the magnetic suspension balance provided by the embodiments of the present application at least solves the problem that the adsorption capacity of helium cannot be accurately and effectively determined in related technologies.

[0007] According to a first aspect of the embodiment of the present application, a helium isothermal adsorption calculation method based on a magnetic suspension balance is provided, comprising:

[0008] After the magnetic suspension balance sample cabin storing a target sample is vacuumized at a first preset temperature for a preset time, a first mass of the target sample is obtained when the magnetic suspension balance sample cabin is at the temperature of an indoor environment;

[0009] A second mass of a sample frame corresponding to the target sample and a sample frame volume are obtained, and a plurality of adsorption temperature points are set, each adsorption temperature point including different adsorption pressure points;

[0010] Readings of the magnetic suspension balance corresponding to each adsorption temperature point and the free-phase helium density in the magnetic suspension balance sample cabin corresponding to each adsorption temperature point are obtained;

[0011] Linear relationship graphs corresponding to each adsorption temperature point are drawn through the readings and the free-phase helium density, and the slopes of the linear relationship graphs are calculated respectively;

[0012] Based on the plurality of adsorption temperature points, the slopes, the first mass, the sample frame volume, and an ideal gas constant, a ternary nonlinear fitting is performed to obtain a unit mass skeleton volume of the target sample;

[0013] Based on the unit mass skeleton volume of the target sample, the first mass, the second mass, the sample frame volume, the readings, the free-phase helium density, and the atomic mass of helium, helium adsorption amounts corresponding to each adsorption temperature point and different adsorption pressure points are calculated;

[0014] Helium isothermal adsorption curves corresponding to each adsorption temperature point are drawn according to the helium adsorption amounts, and the Langmuir formula is used to fit the helium isothermal adsorption curves to obtain a Langmuir maximum adsorption amount and a Langmuir pressure corresponding to each adsorption temperature point.

[0015] According to a second aspect of the embodiment of the present application, an electronic device is provided, comprising a processor, a memory, a communication interface, and a communication bus, the processor, the memory, and the communication interface complete communication with each other through the communication bus; the memory is used to store at least one executable instruction, and the executable instruction causes the processor to perform operations corresponding to the method of the first aspect.

[0016] According to a third aspect of the embodiment of the present application, a computer storage medium is provided, and a computer program is stored on the computer storage medium, the program is executed by a processor to implement the method of the first aspect.

[0017] According to the scheme provided by the embodiment of the present application, the magnetic suspension balance sample cabin storing the target sample is vacuumized at a first preset temperature for a preset time, then the first mass of the target sample is obtained when the magnetic suspension balance sample cabin is at the temperature of the indoor environment; the second mass of the sample frame corresponding to the target sample and the sample frame volume are obtained; a plurality of adsorption temperature points are set, each adsorption temperature point including different adsorption pressure points; the reading of the magnetic suspension balance corresponding to each adsorption temperature point at different adsorption pressure points and the free phase helium density in the magnetic suspension balance sample cabin are obtained; the linear relationship diagram corresponding to each adsorption temperature point is drawn through the reading and the free phase helium density, and the slope of the linear relationship diagram is calculated respectively; the unit mass skeleton volume of the target sample is obtained through the ternary nonlinear fitting based on the plurality of adsorption temperature points, the slope, the first mass, the sample frame volume and the ideal gas constant; the helium adsorption amount corresponding to each adsorption temperature point at different adsorption pressure points is calculated based on the unit mass skeleton volume of the target sample, the first mass, the second mass, the sample frame volume, the reading, the free phase helium density and the atomic mass of helium; the helium isothermal adsorption curve corresponding to each adsorption temperature point is drawn according to the helium adsorption amount, and the Langmuir formula is used to fit the helium isothermal adsorption curve to obtain the Langmuir maximum adsorption amount and the Langmuir pressure corresponding to each adsorption temperature point. In this process, based on the physical principle that the thermodynamic characteristics of helium at different temperatures comply with the Arrhenius equation, combined with the test principle of the magnetic suspension balance and the linear characteristics of the helium isothermal adsorption line, a helium adsorption fitting model (i.e. helium adsorption fitting formula) at multiple temperatures is established; the balance reading isotherm of the target sample after adsorbing helium at different temperatures is determined and drawn by using the magnetic suspension balance, the key parameters such as the unit mass skeleton volume of the sample are determined by using the helium adsorption fitting model, and the helium adsorption amount of the target sample under different temperature and pressure conditions is further calculated, so that the quantitative evaluation of the helium adsorption capacity is realized. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creating laborious work.

[0019] Figure 1 A flowchart of a helium isothermal adsorption measurement method based on a magnetic suspension balance provided by the embodiment of the present application;

[0020] Figure 2 A structural schematic diagram of an electronic device provided by the embodiment of the present application. DETAILED DESCRIPTION

[0021] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some of the embodiments of the present application but not all the embodiments. The following embodiments are used to describe the present application but not to limit the scope of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the scope of protection of the present application.

[0022] In the following description, “some embodiments” are related to a subset of all possible embodiments, but it can be understood that “some embodiments” can be the same subset or different subsets of all possible embodiments and can be combined with each other without conflict.

[0023] It should be noted that the terms “first”, “second”, “third” involved in the embodiments of the present application are only to distinguish similar objects and do not represent a specific order of the objects. Understandably, “first”, “second”, “third” can be interchanged in a specific order or sequence as allowed, so that the embodiments of the present application described here can be implemented in an order other than that illustrated or described here.

[0024] Those skilled in the art can understand that, unless otherwise defined, all terms (including technical terms and scientific terms) used herein have the same meaning as generally understood by those skilled in the art to which the embodiments of the present application belong. It should also be understood that terms such as those defined in general dictionaries should be understood as having meanings consistent with those in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless specifically defined as such.

[0025] Figure 1 A flowchart of a helium isothermal adsorption measurement method based on a magnetic suspension balance provided by the embodiments of the present application. The helium isothermal adsorption measurement method based on a magnetic suspension balance provided by the embodiments of the present application can be executed by an electronic device, which can be a computer, a server, etc.

[0026] As shown in Figure 1 The helium isothermal adsorption measurement method based on a magnetic suspension balance includes:

[0027] S101, after the magnetic suspension balance sample cabin storing the target sample is vacuumized at a first preset temperature for a preset time, the first mass of the target sample is obtained when the magnetic suspension balance sample cabin is at the temperature of the indoor environment.

[0028] In the embodiments of the present application, the target sample generally refers to a material with potential adsorption performance, which can be a porous material (such as activated carbon, zeolite, metal organic framework material (MOF), etc.), a nanostructured material, a new synthetic material, or any other solid material that can be used for gas storage, separation or catalytic applications. Select 2-5 g of the target sample, load it into the magnetic suspension balance sample chamber, vacuumize for 10 hours at a temperature of 433.15 K (the first preset temperature), and after the magnetic suspension balance sample chamber cools to room temperature, record the first mass of the target sample under vacuum conditions.

[0029] S102, obtain the second mass of the sample frame corresponding to the target sample and the volume of the sample frame, and set a plurality of adsorption temperature points, each adsorption temperature point including different adsorption pressure points.

[0030] In the embodiments of the present application, the sample frame is a physical frame or housing that contains the target sample. The second mass of the sample frame is measured, and the volume of the sample frame is measured. A plurality of different adsorption temperature points are set, each adsorption temperature point including a plurality of different adsorption pressure points.

[0031] For example, a plurality of (not less than 6) adsorption temperature points are selected at a temperature of 273.15-423.15 K, each adsorption temperature point including a plurality of (not less than 15) different adsorption pressure points.

[0032] S103, obtain the reading of the magnetic suspension balance corresponding to each adsorption temperature point and the free-phase helium gas density in the magnetic suspension balance sample chamber at different adsorption pressure points.

[0033] In the embodiments of the present application, the reading of the magnetic suspension balance corresponding to each adsorption temperature point and the free-phase helium gas density in the magnetic suspension balance sample chamber at different adsorption pressure points are obtained, and finally a plurality of data sets are obtained, each data set in the plurality of data sets containing an adsorption temperature point, a plurality of different adsorption pressure points, and the reading of the magnetic suspension balance and the free-phase helium gas density in the magnetic suspension balance sample chamber corresponding to each adsorption pressure point.

[0034] S104, draw a linear relationship graph corresponding to each adsorption temperature point by the reading and the free-phase helium gas density, and calculate the slope of the linear relationship graph, respectively.

[0035] In the embodiments of the present application, a linear relationship graph corresponding to each adsorption temperature point is drawn by a plurality of readings and free-phase helium gas densities, and the slope of each linear relationship graph is calculated, and finally each adsorption temperature point corresponds to a slope.

[0036] S105, based on the plurality of adsorption temperature points, the slope, the first mass, the volume of the sample frame, and the ideal gas constant, perform a three-variable nonlinear fitting to obtain the unit mass skeleton volume of the target sample.

[0037] In the embodiments of the present application, the unit mass skeletal volume of the target sample (i.e. the specific skeletal volume or the unit mass skeletal volume) refers to the volume of the real skeleton (excluding pores and voids) occupied by each unit mass of the target sample. Based on multiple adsorption temperature points, slopes, first masses, volumes and ideal gas constants, a ternary nonlinear fitting is performed to obtain the unit mass skeletal volume of the target sample.

[0038] In the embodiments of the present application, based on the test principle of the magnetic suspension balance, the balance reading during the test is equal to the total mass of the sample frame, the target sample and the adsorbed gas minus the buoyancy suffered by the sample frame and the target sample. According to the Archimedes principle, the buoyancy suffered by the sample frame and the target sample is equal to the weight of the free-phase gas displaced by the two, i.e. as shown in the following formula (1).

[0039] (1) ;

[0040] In the above formula (1), m 读 is the reading of the magnetic suspension balance, unit g; m 框 is the second mass, unit g; m 样 is the first mass, unit g; m 吸 is the mass of the target sample adsorbed helium, unit g; V 框 is the volume of the sample frame, unit cm 3 ; v 样 is the unit mass skeletal volume of the target sample, unit cm 3 / g. is the density of free-phase helium, unit g / cm 3 .

[0041] Under low pressure conditions, the helium isothermal adsorption line is usually linear, which obeys Henry's law, as shown in the following formula (2):

[0042] (2) ;

[0043] In the above formula, n 吸 is the helium adsorption amount of the target sample per unit mass, unit mol / g; H is the Henry coefficient, unit mol / g·MPa; and p is different adsorption pressure points, unit MPa.

[0044] The helium adsorption amount per unit mass (n 吸 ) has the following relationship with the mass (m 吸 ) of the adsorbed helium in the experiment:

[0045] (3) ;

[0046] In the above formula, M HeThe atomic mass of helium is 4 g / mol.

[0047] Wherein, the mass of the adsorbed helium in the experiment is the total mass of the helium actually adsorbed by the target sample.

[0048] According to the ideal gas state equation, the different adsorption pressure points p in the experimental device can be shown by formula (4):

[0049] (4);

[0050] In the above formula, n 游 is the amount of free-phase helium, with units of mol; V 游 is the volume of free-phase helium, with units of cm 3 ; R is the ideal gas constant, with a value of 8.314 J / (mol·K); T is the multiple adsorption temperature points, with units of K; m 游 is the mass of free-phase gas, with units of g, is the density of free-phase helium, with units of g / cm 3 .

[0051] Formula (3) and (4) are brought into formula (2) and converted to obtain the following formula (5):

[0052] (5);

[0053] Formula (5) is brought into formula (1) and converted to obtain the following formula (6):

[0054] (6);

[0055] In the helium isothermal adsorption experiment at a specific temperature, the sample frame mass (m 框 ) and the first mass (m 样 ) in formula (6) are both constants, the free-phase helium density (m ) is a variable that changes with the experimental pressure, the coefficients in the formula are also constants, so the reading (m 读 ) of the magnetic suspension balance obtained in the experiment should be in a linear linear relationship with the free-phase helium density (m ), and the slope k of the linearity can be expressed by the following formula:

[0056] (7);

[0057] The relationship between the Henry coefficient (H) of helium adsorption and the multiple adsorption temperature points (T) obeys the Arrhenius equation, that is:

[0058] (8);

[0059] In the above formula, H0 is the adsorption enthalpy coefficient, with the unit of mol / g·MPa; and H1 is the equivalent adsorption heat, with the unit of J / mol.

[0060] The formula (8) is brought into the formula (7) and converted to obtain:

[0061] (9).

[0062] The formula (9) is a helium adsorption fitting model (i.e., a helium adsorption fitting formula) under multiple temperatures. In the helium isothermal adsorption experiments at different temperatures carried out by the magnetic suspension balance on the same target sample, T in the formula (9) is the independent variable, k is the dependent variable, R, m 样 , and V 框 are known constants, H0, H1, and v 样 are unknown constants, and the values of H0, H1, and v 样 can be determined by using a ternary nonlinear fitting method.

[0063] S106, based on the unit mass skeleton volume of the target sample, the first mass, the second mass, the sample frame volume, the reading, the free-phase helium density, and the atomic mass of helium, the helium adsorption amount corresponding to each adsorption temperature point under different adsorption pressure points is calculated.

[0064] In the embodiments of the present application, the helium adsorption amount refers to the adsorption amount of helium molecules on the surface or internal pores of a material. According to the helium adsorption amount formula, the unit mass skeleton volume, the first mass, the second mass, the sample frame volume, the reading, the free-phase helium density, and the atomic mass of helium, the helium adsorption amount corresponding to each adsorption temperature point under different adsorption pressure points is calculated, and finally a plurality of helium adsorption amounts corresponding to each adsorption temperature point are obtained. The helium adsorption amount formula is shown in the following formula (10):

[0065] (10).

[0066] In the above formula (10), n 吸 is the helium adsorption amount of the target sample per unit mass, m 读 is the reading of the magnetic suspension balance, m 框 is the second mass, m 样 is the first mass, m 吸 is the mass of the target sample adsorbing helium, V 框 is the sample frame volume, v 样 is the unit mass skeleton volume, is the free-phase helium density.

[0067] S107, draw the helium isothermal adsorption curve corresponding to each adsorption temperature point according to the helium adsorption amount, and fit the helium isothermal adsorption curve by using the Langmuir formula to obtain the Langmuir maximum adsorption amount and the Langmuir pressure corresponding to each adsorption temperature point.

[0068] In the embodiment of the present application, the helium isothermal adsorption curve corresponding to each adsorption temperature point is drawn according to the helium adsorption amount, and the helium isothermal adsorption curve includes each adsorption pressure point and the corresponding helium adsorption amount. The Langmuir formula is as follows:

[0069] (11);

[0070] In the above formula (11), n0 is the Langmuir maximum adsorption amount, with units of mol / g; P L is the Langmuir pressure, with units of MPa.

[0071] It can be understood that in the embodiment of the present application, after the magnetic levitation balance sample cabin storing the target sample is vacuumed at the first preset temperature for a preset time, the first mass of the target sample is obtained when the magnetic levitation balance sample cabin is at the temperature of the indoor environment; the second mass of the sample frame corresponding to the target sample and the sample frame volume are obtained, and a plurality of adsorption temperature points are set, each adsorption temperature point including different adsorption pressure points; the reading of the magnetic levitation balance corresponding to each adsorption temperature point under different adsorption pressure points and the free-phase helium density in the magnetic levitation balance sample cabin are obtained; the linear relationship diagram corresponding to each adsorption temperature point is drawn through the reading and the free-phase helium density, and the slope of the linear relationship diagram is calculated respectively; based on the plurality of adsorption temperature points, the slope, the first mass, the sample frame volume and the ideal gas constant, a ternary nonlinear fitting is performed to obtain the unit mass skeleton volume of the target sample; based on the unit mass skeleton volume of the target sample, the first mass, the second mass, the sample frame volume, the reading, the free-phase helium density and the atomic mass of helium, the helium adsorption amount corresponding to each adsorption temperature point under different adsorption pressure points is calculated, the helium isothermal adsorption curve corresponding to each adsorption temperature point is drawn according to the helium adsorption amount, and the helium isothermal adsorption curve is fitted by using the Langmuir formula to obtain the Langmuir maximum adsorption amount and the Langmuir pressure corresponding to each adsorption temperature point. In this process, based on the physical principle that the helium adsorption thermodynamic characteristics at different temperatures obey the Arrhenius equation, combined with the testing principle of the magnetic levitation balance and the linear characteristics of the helium isothermal adsorption line, a helium adsorption fitting model at multiple temperatures is established; the balance reading isotherm of the target sample after adsorbing helium at different temperatures is determined and drawn by using the magnetic levitation balance, the key parameters such as the unit mass skeleton volume of the sample are determined by using the helium adsorption fitting model, and the helium adsorption amount of the target sample under different temperature and pressure conditions is further calculated, so as to realize the quantitative evaluation of the helium adsorption capacity.

[0072] In some embodiments of the application, S102 can be implemented by S1021, which is described by the following steps.

[0073] S1021, find the parameter of the sample frame in the hardware parameters of the magnetic levitation balance, and obtain the second mass and the volume of the sample frame based on the parameter.

[0074] In some embodiments of the application, the hardware parameters of the magnetic levitation balance include a plurality of parameters, the parameter of the sample frame is found in the plurality of parameters, and then the second mass and the volume of the sample frame are obtained.

[0075] Referring to Figure 2 , a structural schematic diagram of an electronic device according to an embodiment of the application is shown, and the specific implementation of the electronic device is not limited in the embodiments of the application.

[0076] As Figure 2 shown, the electronic device can include a processor 502, a communications interface 504, a memory 506, and a communications bus 508.

[0077] Among them:

[0078] The processor 502, the communications interface 504, and the memory 506 complete mutual communication through the communications bus 508.

[0079] The communications interface 504 is configured to communicate with other electronic devices or servers.

[0080] The processor 502 is configured to execute the program 510, and specifically can execute the related steps in the above method embodiments.

[0081] Specifically, the program 510 can include program code, and the program code includes computer operation instructions.

[0082] The processor 502 can be a central processing unit CPU, or an application specific integrated circuit ASIC, or one or more integrated circuits configured to implement embodiments of the application. One or more processors included in the smart device can be the same type of processor, such as one or more CPUs; or can be different types of processors, such as one or more CPUs and one or more ASICs.

[0083] The memory 506 is configured to store the program 510. The memory 506 can include a high-speed RAM memory, and can also include a non-volatile memory, such as at least one disk memory.

[0084] The program 510 can be specifically configured to enable the processor 502 to perform operations corresponding to the methods described in the above method embodiments.

[0085] The specific implementation of each step in the program 510 can refer to the corresponding description in the corresponding steps and units in the above method embodiments, and will not be described here. It can be clearly understood by those skilled in the art that, for the convenience and brevity of description, the specific working processes of the devices and modules described above can refer to the corresponding process description in the foregoing method embodiments, and will not be described here.

[0086] It should be noted that, according to the needs of implementation, each component / step described in the embodiments of the present application can be split into more components / steps, or two or more components / steps or part of the operation of the components / steps can be combined into a new component / step, to achieve the purpose of the embodiments of the present application.

[0087] The above method according to the embodiments of the present application can be implemented in hardware, firmware, or as software or computer code that can be stored in a recording medium such as a CD ROM, a RAM, a floppy disk, a hard disk or an optical disk, or be implemented by computer code originally stored in a remote recording medium or a non-transitory machine readable medium and downloaded to a local recording medium, so that the method described herein can be processed by such software on a recording medium using a general computer, a special processor or programmable or special hardware such as an ASIC or an FPGA. It can be understood that the computer, processor, microprocessor controller or programmable hardware includes a storage component (for example, RAM, ROM, flash memory, etc.) that can store or receive software or computer code, when the software or computer code is accessed and executed by the computer, processor or hardware, the method described herein is implemented. In addition, when a general computer accesses the code for implementing the method shown herein, the execution of the code will convert the general computer into a special computer for executing the method shown herein.

[0088] Those of ordinary skill in the art can realize that the units and method steps of each example described in combination with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether the functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the embodiments of the present application.

[0089] The above embodiments are only used for describing the present application, and not intended to limit the present application. Any modification and change made by those skilled in the art without departing from the spirit and scope of the present application shall be included in the scope of the present application. The patent protection scope of the present application shall be defined by the claims.

Claims

1. A helium isothermal adsorption measurement method based on a magnetic suspension balance, characterized in that: include: After evacuating a magnetic levitation balance sample chamber storing a target sample at a first preset temperature for a preset time, obtaining a first mass of the target sample when the magnetic levitation balance sample chamber is at a temperature of an indoor environment; Obtaining a second mass and a volume of a sample frame corresponding to the target sample, and setting a plurality of adsorption temperature values, each of which includes a different adsorption pressure point; Obtaining the readings of the magnetic suspension balance corresponding to different adsorption pressure points at each adsorption temperature value and the free-phase helium density in the sample chamber of the magnetic suspension balance; Draw a linear relationship graph corresponding to each adsorption temperature value using the reading and the free phase helium density, and calculate the slope of the linear relationship graph respectively; Performing a ternary nonlinear fitting based on the multiple adsorption temperature values, the slope, the first mass, the sample frame volume, and the ideal gas constant to obtain a unit mass skeleton volume of the target sample; Calculating the helium adsorption amount corresponding to each adsorption pressure point at each adsorption temperature value based on the unit mass skeleton volume of the target sample, the first mass, the second mass, the sample frame volume, the reading, the free phase helium density and the atomic mass of helium; The helium adsorption isotherm curve corresponding to each adsorption temperature value is drawn according to the helium adsorption amount, and the helium adsorption isotherm curve is fitted using the Langmuir formula to obtain the Langmuir maximum adsorption amount and Langmuir pressure corresponding to each adsorption temperature value.

2. The method according to claim 1, characterized in that The obtaining of the second mass and volume of the sample frame corresponding to the target sample includes: The parameters of the sample frame are traversed from the hardware parameters of the magnetic suspension balance, and the second mass and the volume of the sample frame are acquired based on the parameters.

3. The method according to claim 1, characterized in that The calculating of the helium adsorption amount corresponding to each adsorption pressure point at each adsorption temperature value based on the unit mass skeleton volume of the target sample, the first mass, the second mass, the sample frame volume, the reading, the free phase helium density, and the atomic mass of helium includes: The helium adsorption amount corresponding to each adsorption pressure point at each adsorption temperature value is calculated according to the helium adsorption amount formula, the unit mass skeleton volume, the first mass, the second mass, the sample frame volume, the reading, the free phase helium density, and the atomic mass of helium, wherein the helium adsorption amount formula is as follows: （10） In the above formula, is the helium adsorption amount of the target sample per unit mass, is the reading of the magnetic suspension balance, is the second mass, is the first mass, is the sample frame volume, is the unit mass skeleton volume, is the free phase helium density, M He is the atomic mass of helium.

4. The method according to claim 3, characterized in that The performing of ternary nonlinear fitting based on the multiple adsorption temperature values, the slope, the first mass, the sample frame volume, and the ideal gas constant to obtain the unit mass skeleton volume of the target sample includes: A ternary nonlinear fitting is performed based on a helium adsorption fitting formula, the multiple adsorption temperature values, the slope, the first mass, the volume, and the ideal gas constant to obtain the unit mass skeletal volume of the target sample, wherein the helium adsorption fitting formula is as follows: （9） In the above formula, k is the slope, H0 is the adsorption enthalpy change coefficient, H1 is the isosteric adsorption heat, T is the adsorption temperature value, R is the ideal gas constant, and the adsorption temperature value is the temperature value of the magnetic suspension balance sample chamber when the helium is adsorbed on the target sample.

5. The method according to claim 1, wherein The Langmuir formula is as follows: （11） In the above formula, P are the different adsorption pressure points, n0 is the maximum Langmuir adsorption capacity, P L For Langmuir pressure.

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