Device for analyzing gas charged in sample and device for analyzing gas permeated through sample

Abstract

The present invention relates to a device for analyzing a gas charged in a sample, the apparatus comprising: a sample chamber in which the sample charged with the gas is disposed; a cylinder extending from the sample chamber in one direction and partially filled with a fluid; a transparent conductive electrode surrounding the outer circumference of the cylinder and extending in the one direction; a central electrode which is located at the center of the cylinder and extends in the one direction; a capacitance detector for detecting a capacitance value of the capacitor formed by the level of the fluid in the cylinder due to the gas discharged from the sample; and a calculation device, wherein the calculation device analyzes the gas charged in the sample from the capacitance value.

Description

Gas analysis device loaded into the sample and gas analysis device permeating the sample

[0001] The present disclosure generally relates to a gas analysis device loaded with a sample and a gas analysis device permeating a sample.

[0002] Reducing carbon dioxide emissions is essential to prevent environmental degradation caused by global warming, fossil fuel depletion is expected in the near future, and humanity has repeatedly experienced the dangers of nuclear power, making the development of clean and renewable energy essential.

[0003] In response to these demands, hydrogen is receiving significant attention as an energy source. While hydrogen can be obtained from fossil fuels, industrial process byproducts, and biomass, it is ultimately produced through water electrolysis using renewable energy. It reacts with oxygen to generate electricity, producing no carbon dioxide emissions, making it an ideal clean energy source.

[0004] Not only hydrogen, but also gas infrastructure uses materials to prevent and seal gas leaks, but gas that penetrates organic materials such as plastic or rubber can cause a deterioration in physical properties, such as swelling and bursting (blister destruction) or loss of elasticity.

[0005] One of the challenges to be addressed by this technology is to provide a technology for analyzing the amount of gas introduced, concentration, and diffusion coefficient in the material to prevent the material's properties from being deteriorated by the introduction of gas into the material.

[0006] The present embodiment is a device for analyzing a gas loaded into a sample, comprising: a sample chamber in which the sample loaded with the gas is placed; a cylinder extending in one direction from the sample chamber and having a portion of the cylinder filled with a fluid; a transparent conductive electrode surrounding the outer periphery of the cylinder and extending in the one direction; a center electrode positioned at the center of the cylinder and extending in the one direction; a capacitance detector for detecting a capacitance value of the capacitor formed by the level of the fluid in the cylinder due to the gas emitted from the sample; and a calculation device, wherein the calculation device analyzes the gas loaded into the sample from the capacitance value.

[0007] According to one aspect of the present embodiment, the transparent conductive electrode is any one of ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), graphene, silver nanowire, and CNT (Carbon Nano Tube).

[0008] According to one aspect of the present embodiment, the center electrode is a conductive metal wire comprising any one of a copper wire, an aluminum wire, and a stainless steel wire.

[0009] According to one aspect of the present embodiment, the sample chamber further includes a sealing member and a cover member that have an outer circumference larger than the outer circumference of the cylinder to accommodate the sample and seal the cylinder.

[0010] According to one aspect of the present embodiment, the computing device comprises:

[0011] The water level (h) is calculated by calculating .

[0012] L: one-way length of the capacitor, R1: radius of the center electrode, R2: inner radius of the transparent conductive coaxial electrode as the outer electrode, and ε 0: Permittivity of free space, εw : Permittivity of the fluid, ε g : dielectric constant of gas)

[0013] According to one aspect of the present embodiment, the computing device computes the volume of gas released from the sample from a second-order polynomial for the correlation between the water level and the capacitance obtained through quadratic regression.

[0014] According to one aspect of the present embodiment, the calculating device obtains the number of moles of the gas released from the sample from the volume of gas released from the calculated sample, and the number of moles of the gas is expressed by the mathematical formula

[0015]

[0016]

[0017] It is performed by calculating .

[0018] (T0: Initial temperature of the gas inside the cylinder, P0: Initial pressure of the gas inside the cylinder, V A : Initial residual air volume, V H (t): Volume of gas released, V(t)=V A + V H (t), n A is the initial number of air moles, n H (t) is the number of moles of gas released)

[0019] According to one aspect of the present embodiment, the computing device obtains the gas concentration of the gas emitted from the sample, and the concentration of the gas (C(t)) is expressed by the mathematical formula

[0020]

[0021] It is performed by calculating .

[0022] (m H [g / mol]: molar mass of gas evolved from the sample, m sample is the mass of the sample)

[0023] According to one aspect of the present embodiment, the method further comprises a step of obtaining the gas diffusion coefficient of the sample, wherein the step of obtaining the gas diffusion coefficient (D) comprises:

[0024] Mathematical formula

[0025]

[0026] It is performed by calculating .

[0027] (β n: Roots of the zeroth-order Bessel function J0(βn), D: diffusion coefficient, C ∞ : gas absorption or loading amount of the sample, l: thickness of the sample, ρ: radius of the sample)

[0028] The present embodiment is a device for analyzing a gas that passes through a sample, comprising: a gas permeator including an inlet for introducing gas, a sealed sample chamber in which a sample is placed, and an outlet for discharging a gas that has passed through the sample; a cylinder extending in one direction and partially filled with a fluid, into which a gas that has passed through the sample flows; a transparent conductive electrode surrounding an outer periphery of the cylinder and extending in the one direction; a center electrode positioned at the center of the cylinder and extending in the one direction; a capacitance detector for detecting a capacitance value of the capacitor formed by a change in the level of the fluid in the cylinder due to the gas that has passed through the sample; and a computing device, wherein the computing device analyzes the gas that has passed through the sample from the capacitance value.

[0029] According to one aspect of the present embodiment, the gas permeator includes a first member having an inlet through which high-pressure gas flows in; a sample chamber in which the sample is placed; a sealing member sealing the sample chamber; and a second member having an outlet through which gas that has permeated the sample flows out.

[0030] According to one aspect of the present embodiment, the transparent conductive electrode is any one of ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), graphene, silver nanowire, and CNT (Carbon Nano Tube).

[0031] According to one aspect of the present embodiment, the center electrode is a conductive metal wire comprising any one of a copper wire, an aluminum wire, and a stainless steel wire.

[0032] According to one aspect of the present embodiment, the computing device comprises:

[0033] The water level (h) is calculated by calculating .

[0034] L: length of the capacitor in one direction, R1: radius of the center electrode, R2: inner radius of the transparent conductive coaxial electrode as the outer electrode, and ε 0: Permittivity of free space, ε w : Permittivity of the fluid, ε g : dielectric constant of gas)

[0035] According to one aspect of the present embodiment, the computing device computes the volume of gas released from the sample from a second-order polynomial for the correlation between the water level and the capacitance obtained through quadratic regression.

[0036] According to one aspect of the present embodiment, the calculating device obtains the number of moles of the gas released from the sample from the volume of gas released from the calculated sample, and the number of moles of the gas is expressed by the mathematical formula

[0037]

[0038]

[0039] It is performed by calculating .

[0040] (T0: Initial temperature of the gas inside the cylinder, P0: Initial pressure of the gas inside the cylinder, V A : Initial residual air volume, V H (t): Volume of gas released, V(t)=V A + V H (t), n A is the initial number of air moles, n H (t) is the number of moles of gas released)

[0041] According to one aspect of the present embodiment, the computing device obtains the gas concentration of the gas emitted from the sample, and the concentration of the gas (C(t)) is expressed by the mathematical formula

[0042]

[0043] It is performed by calculating .

[0044] (m H [g / mol]: molar mass of gas evolved from the sample, m sample is the mass of the sample)

[0045] According to one aspect of the present embodiment, the step of obtaining the gas diffusion coefficient of the sample is further included, wherein the step of obtaining the gas diffusion coefficient (D) is expressed by the mathematical formula

[0046]

[0047] It is performed by calculating .

[0048] (β n: Roots of the zeroth-order Bessel function J0(βn), D: diffusion coefficient, C ∞ : gas absorption or loading amount of the sample, l: thickness of the sample, ρ: radius of the sample)

[0049] According to one aspect of the present embodiment, the gas permeability of the sample is expressed by the mathematical formula It is calculated as follows.

[0050] (A: gas contact area of ​​the sample in the gas permeator, ΔP: pressure gradient difference between the supply side and the permeate side in the gas permeation, l: thickness of the sample, Δn / Δt: moles of permeate gas per hour)

[0051] According to this embodiment, the advantage of being able to effectively measure gas concentration, leakage and diffusion without chemical reaction with target gas molecules is provided.

[0052] Fig. 1(a) is a schematic diagram illustrating an outline of a chamber for charging a sample with gas in a high-pressure environment, and Fig. 1(b) is a schematic diagram illustrating a cylinder in which a sample charged with gas is placed.

[0053] Figure 2 is a schematic diagram of a device for analyzing a gas passing through a sample.

[0054] FIG. 3(a) is a drawing showing a cross-section cut perpendicular to the longitudinal axis of the cylinder (100) illustrated in FIGS. 1 and 2, FIG. 3(b) is a perspective view of the cylinder, and FIG. 3(c) is a longitudinal cross-sectional view of the cylinder.

[0055] Fig. 4 is a drawing showing an outline of a gas analysis device according to the present embodiment.

[0056] Figure 5(a) is a diagram showing the relationship between the amount of water and capacitance, Figure 5(b) is a diagram showing the relationship between capacitance and the volume of water, Figure 5(c) is a diagram showing the hydrogen emission (in wt-ppm) over time, and Figure 5(d) is a diagram showing the diffusion and total absorption (D and C ∞ ) is an example drawing.

[0057] Figure 6 is a diagram showing the time after pressurization of a cylindrical specimen of EPDM polymer versus hydrogen permeating and leaking through the sample.

[0058] Fig. 7(a) shows the results of analyzing He gas in this example, Fig. 7(b) shows the results of analyzing N2 gas in this example, Fig. 7(c) shows the results of analyzing O2 gas in this example, and Fig. 7(d) shows the results of analyzing Ar gas in this example.

[0059]

[0060] Fig. 1(a) is a schematic diagram illustrating an outline of a chamber for charging a sample with gas in a high-pressure environment, and Fig. 1(b) is a schematic diagram illustrating a cylinder in which a sample charged with gas is placed.

[0061] Figure 2 is a schematic diagram of a device for analyzing a gas passing through a sample.

[0062] FIG. 3(a) is a drawing showing a cross-section cut perpendicular to the longitudinal axis of the cylinder (100) illustrated in FIGS. 1 and 2, FIG. 3(b) is a perspective view of the cylinder, and FIG. 3(c) is a longitudinal cross-sectional view of the cylinder.

[0063] Fig. 4 is a drawing showing an outline of a gas analysis device according to the present embodiment.

[0064] Figure 5(a) is a diagram showing the relationship between the amount of water and capacitance, Figure 5(b) is a diagram showing the relationship between capacitance and the volume of water, Figure 5(c) is a diagram showing the hydrogen emission (in wt-ppm) over time, and Figure 5(d) is a diagram showing the diffusion and total absorption (D and C ∞ ) is an example drawing.

[0065] Figure 6 is a diagram showing the time after pressurization of a cylindrical specimen of EPDM polymer versus hydrogen permeating and leaking through the sample.

[0066] Fig. 7(a) shows the results of analyzing He gas in this example, Fig. 7(b) shows the results of analyzing N2 gas in this example, Fig. 7(c) shows the results of analyzing O2 gas in this example, and Fig. 7(d) shows the results of analyzing Ar gas in this example.

[0067] Hereinafter, the present embodiment will be described with reference to the attached drawings. Hereinafter, the present embodiment will be described with reference to the attached drawings. The present embodiment is a device for analyzing a gas loaded into a sample, the device including: a sample chamber (110) in which the sample loaded with the gas is placed; a cylinder (100) extending in one direction from the sample chamber (110) so that a portion of the cylinder (100) is filled with a fluid; a transparent conductive electrode surrounding the outer periphery of the cylinder () and extending in the one direction; a center electrode located at the center of the cylinder and extending in the one direction; and a calculation device for detecting a change in capacitance of the capacitor formed by a change in the level of the fluid in the cylinder due to a gas emitted from the sample, wherein the calculation device analyzes the gas loaded into the sample from the change in capacitance.

[0068] Fig. 1(a) is a schematic diagram illustrating an outline of a chamber for injecting gas into a sample in a high-pressure environment, and Fig. 1(b) is a schematic diagram illustrating a cylinder in which a sample loaded with gas is placed. Referring to Fig. 1(a), the chamber is formed of stainless steel (SUS 316) so as not to be damaged even under high pressure in order to expose the sample to high-pressure gas. A gas inlet for injecting gas is located on one side of the chamber, and a gas outlet for discharging gas is located on the other side. A pressure gauge for measuring the pressure inside the chamber is included, and a sample is placed inside the chamber.

[0069] For example, the sample may be one or more materials such as NBR or EPDM, which are used as sealing and shielding components such as O-rings and seals in hydrogen infrastructure. As another example, the sample may be one or more materials such as HDPE and LDPE, which are used as liner materials for Type IV containers of fuel cell electric vehicles.

[0070] The NBR sample was formed into a cylinder with a radius of 5.9 mm and a thickness of 2.1 mm, and the EPDM sample was formed into a cylinder with a radius of 5.9 mm and a thickness of 2.3 mm. In addition, the HDPE sample was formed into a cylinder with a radius of 5.9 mm and a thickness of 2.4 mm, and the LDPE sample was formed into a cylinder with a radius of 6.5 mm and a thickness of 2.4 mm.

[0071] The above radius, thickness, and shape can all be applied differently depending on the embodiment and measurement environment, and the size and thickness of the sample can be measured by changing them, and the shape of the sample can be various other shapes such as a hexahedron, a tetrahedron, and a sphere.

[0072] The processed sample is exposed to a high-pressure gas environment inside the chamber. The sample is placed in a chamber at room temperature and exposed to a high-pressure gas environment. The pressure of hydrogen (H2) was 2 to 90 MPa, and the pressure of other gases was 2 to 10 MPa. The purity of the hydrogen (H2) gas used was 99.999%, the purity of the helium (He) gas was 99.999%, the purity of the nitrogen (N2) gas was 99.999%, the purity of the oxygen (O2) gas was 99.99%, and the purity of the argon (Ar) gas was 99.999% 0.

[0073] After purging the chamber with the gas three times at a pressure ranging from 1 MPa to 3 MPa, depending on the pre-exposure pressure, the samples were exposed to the gas at the specified pressure for 24 to 48 hours. A 48-hour gas exposure is sufficient to reach equilibrium for gas adsorption.

[0074] Referring to Fig. 1(b), a sample loaded with gas is placed in a sample chamber (110) of a cylinder (100) and sealed with a sealing member (114). In one embodiment, the sample chamber (110) has an outer circumference larger than the outer circumference of the cylinder (110) to form a space for accommodating the sample. The sample chamber (110) may further include a sealing member (112, see Fig. 3(c)) such as an O-ring for sealing the cylinder and a sealing member (114) for sealing the sample chamber.

[0075] FIG. 2 is a schematic diagram illustrating a device for analyzing a gas passing through a sample. Referring to FIG. 2, the present embodiment is a device for analyzing a gas passing through a sample, comprising: a gas permeator (200) including an inlet (212) for introducing gas, a sealed sample chamber (220) in which a sample is placed, and an outlet (232) for discharging a gas passing through the sample; a cylinder (100) extending in one direction and partially filled with a fluid, into which a gas passing through the sample flows; a transparent conductive electrode surrounding the outer periphery of the cylinder and extending in the one direction; a center electrode located at the center of the cylinder and extending in the one direction; and a capacitance detector for detecting a change in capacitance of the capacitor formed by a change in the level of the fluid within the cylinder due to the gas passing through the sample, wherein the capacitance detector analyzes a gas charged into the sample from the change in capacitance.

[0076] The gas permeator (200) includes a first member (210) and a second member (230) that are sealedly connected to each other with bolts and nuts, and a sealed sample chamber (220) in which a sample is placed is located between the first member (210) and the second member (230).

[0077] High-pressure gas is introduced through the inlet (212) of the first member (210). In one embodiment, the introduced gas may be the same gas as the gas illustrated in FIG. 1, and the introduced pressure may be 2 MPa to 90 MPa.

[0078] The introduced gas enters the sample chamber (220), permeates the sample, and is supplied to the cylinder (100) through the outlet (232) formed in the second member (230). As in the illustrated embodiment, sealing members such as ○ rings are positioned at the top and bottom of the sample to prevent the introduced gas from leaking to the outside. In one embodiment, the gas that has permeated the sample may pass through a metal filter and proceed to the outlet.

[0079] FIG. 3(a) is a drawing showing a cross-section taken perpendicular to the longitudinal axis of the cylinder (100) illustrated in FIGS. 1 and 2, FIG. 3(b) is a perspective view of the cylinder, and FIG. 3(c) is a longitudinal cross-sectional view of the cylinder. Referring to FIGS. 1 to 3, a transparent conductive electrode (320) is positioned on the outer periphery of the cylinder (100) and extends in the longitudinal direction of the cylinder, surrounding the outer periphery of the cylinder (100). The transparent conductive electrode (320) may be formed of any one of ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), graphene, silver nanowires, and CNT (Carbon Nano Tube). Since the transparent electrode (320) is formed to surround the outer periphery of the cylinder (100), the advantage of allowing the water level inside the cylinder (100) to be checked more easily and simply is provided.

[0080] A center electrode (310) may be positioned in the center of the cylinder (100) in the longitudinal direction of the cylinder (100). The center electrode (310) may be formed of a conductive wire, and may be formed of any one of a copper wire, an aluminum wire, and a stainless steel wire.

[0081] A capacitor is formed between the central electrode (310) and the transparent conductive electrode (320). As the gas charged into the sample is released or the gas that has permeated the sample is supplied to the cylinder, the water level inside the cylinder changes. This changes the material located between the two electrodes, thereby changing the dielectric constant, and consequently, the capacitance value of the capacitor formed between the central electrode (310) and the transparent conductive electrode (320) changes.

[0082] The capacitance value of the capacitor formed between the center electrode (310) and the transparent conductive electrode (320) is detected by a capacitance detector (500, see FIG. 4) and provided to an operation device (400) to be described later.

[0083] The cylinder (100) can be maintained in a sealed state with a sealing member (112) such as a ○ ring and a sealing member (114) to prevent gas from being discharged to the outside. The cylinder exemplified in Fig. 3(c) has a sample chamber (110) illustrated, and a communication hole can be formed in the sealing member so that a permeating gas can flow into the cylinder through a tube or the like, as exemplified in Fig. 2. In addition, the inside of the cylinder (100) can be filled with water in advance so that the water is positioned inside the cylinder, and then the gas can be made to change the water level.

[0084] FIG. 4 is a diagram illustrating an outline of a gas analysis device according to the present embodiment. Referring to FIG. 4, the gas analysis device may include a plurality of cylinders (100a, 100b, 100c) and a capacitance detection device that detects capacitance for each cylinder. The capacitance measuring devices (500a, 500b, 500c) may be interfaced with a computing device (400) to provide the measured capacitance. Although the example illustrated in FIG. 4 illustrates three cylinders and capacitance measuring devices, this is merely an example, and an embodiment including one cylinder and one capacitance measuring device is also possible.

[0085] The computing device (400) may be a computing device such as a desktop computer, a workstation, a computing terminal, a tablet, etc., and may perform the calculation described below from data provided by the capacitance detection device to calculate the volume, mole number, concentration, and diffusion coefficient of the gas emitted from the sample.

[0086] P(t) and V(t) of the gas inside the cylinder are expressed as in mathematical equation 1 below.

[0087] [Mathematical Formula 1]

[0088]

[0089] Here P o is the atmospheric pressure outside the cylinder, ρ is the density of the distilled water in the reservoir, g is the acceleration of gravity, h(t) is the level of the distilled water volume inside the cylinder measured from the water level in the water tank, V o is the total volume of gas and distilled water inside the cylinder measured at the water level of the reservoir, and varies with time. V h (t) is the volume of distilled water inside the cylinder marked with a scale measured from the water level of the reservoir, and the volume of the sample is V s is the volume of the sample.

[0090] The transparent conductive electrode (320) and the center electrode (310) form a capacitor, and the capacitance of the capacitor changes depending on the characteristics of the object located between the transparent conductive electrode (320) and the center electrode (310).

[0091] As illustrated in the example of Fig. 1, gas loaded into a sample can be released to change the water level within the cylinder. Additionally, as illustrated in the example of Fig. 2, permeating gas that has permeated the sample can change the water level within the cylinder.

[0092] A capacitance detection device detects capacitance (C) and provides it to a calculation device (400). The calculation device (400) can calculate the difference (ΔC) between the capacitance value provided at a reference point (e.g., the measurement start point) and the provided capacitance value and the change in water level (Δh) in the cylinder from mathematical expression 2.

[0093] [Equation 2]

[0094]

[0095] (h: water level, L: one-way length of the capacitor, R1: radius of the center electrode, R2: inner radius of the transparent conductive coaxial electrode as the outer electrode, and ε 0: Permittivity of free space, ε w : Permittivity of the fluid, ε g : dielectric constant of gas)

[0096] The calculating device (400) can obtain the volume of gas emitted from the sample or gas that has permeated the sample from the change in water level, and can obtain the total number of moles n(t) of gas emitted from the sample using the following mathematical expression 3.

[0097] [Equation 3]

[0098]

[0099]

[0100] Here, T0 and P0 are the initial temperature and pressure of the gas inside the cylinder, respectively, and V(t) is the initial residual air volume (V a ) and gas volume V gas (t), that is, V(t)=V air + V gas (t) and n air is the initial number of air moles and n gas (t) is the number of moles of gas that changes over time, corresponding to the increase in gas volume due to the gas.

[0101] n gas(t) is the concentration of the released gas, and C(t) is converted to the concentration of gas released per mass from the sample as shown in Equation 4 below.

[0102] [Equation 4]

[0103]

[0104] Here m gas [g / mol] is the molar mass of the gas released from the sample (e.g., for H2, m H2 [g / mol] = 2.016 g / mol, m sample is the mass of the sample. According to Equations 2 and 3, the number of moles of gas n that changes over time gas (t) is the scale-up factor k = [m gas / m sample ] is converted to gas mass concentration C(t). n gas (t) and C(t) are affected by changes in environmental temperature and pressure. To ensure accurate measurements, these changes are compensated for.

[0105] Assuming that the gas evolution is a Pickian diffusion process, the diffusion coefficient D of the sample is the concentration C of the evolved gas. E (t) can be calculated by calculating mathematical expression 5.

[0106] [Equation 5]

[0107]

[0108] Here β n is β1= 2.40483, β2= 5.52008, β3= 8.65373, ..., β 50 = 156.295 is the root of the zeroth-order Bessel function J0(βn). Equation 4 is an infinite series expansion with two sums. This equation provides a solution to Fick's second diffusion equation for a cylindrical sample. Here, at t = 0, C E = 0 and when t =∞, C E = C ∞ It is. C ∞is the saturated gas concentration at infinite time, i.e., the gas absorption. D is the diffusion coefficient, and l and ρ are the thickness and radius of the cylindrical sample, respectively. Therefore, the diffusion coefficient D can be obtained from the above mathematical equation 4.

[0109] Below, we describe the process for calculating the gas permeability of a sample. First, the number of moles of diffused gas per unit area, Q(t), can be expressed as in Equation 6.

[0110] [Equation 6]

[0111]

[0112] where C0 is the initial concentration of the sample at t = 0 for 0 < x < l, C1 is the concentration of the high-pressure part of the sample at x = 0, and C2 is the concentration of the low-pressure part of the sample at x = l. A: Contact area between the sample and the gas

[0113] According to the experimental arrangement of the permeation cell, for a specimen with thickness l, the polymer specimen was initially at zero concentration (C0= 0), and the concentration at the surface through which the gas diffused (x = l) was effectively maintained at zero concentration (C2= 0).

[0114] The summation using the infinite series expansion of Equation 6 included 50 terms in the actual calculation. The terms above the 50th term were sufficiently small and negligible. A diffusion-permeation analysis program was developed to analyze the 50 terms and derive the diffusion coefficient using Equation 6. Furthermore, the permeability can be inferred from the linear slope, as shown in Equation 7 below.

[0115] [Equation 7]

[0116]

[0117] (A: gas contact area of ​​the sample in the gas permeator, ΔP: pressure gradient difference between the supply side and the permeate side in the gas permeation, l: thickness of the sample, Δn / Δt: moles of permeate gas per hour)

[0118] Experimental example

[0119] Hereinafter, the process of obtaining diffusion parameters for a cylindrical NBR polymer sample through this example is described. Figure 5(a) is a diagram showing the relationship between the amount of water and the capacitance. As a result of measuring the water level against the capacitance, a second-order polynomial equation for the correlation between the water level and the capacitance was obtained through quadratic regression, and the correlation coefficient is R 2 = 0.999, which is the same as Fig. 5(a).

[0120] Next, the capacitance was converted into water volume, as shown in Fig. 5(b). The black and blue circles correspond to the capacitance and water volume, respectively, and were compared with the elapsed time after depressurization.

[0121] As shown in Fig. 5(c), the water level was converted into the volume of released hydrogen gas, and then converted into the hydrogen emission (unit: wt-ppm) through mathematical equations 3 and 4, and the final loading amount was 400.9 wt ppm, as shown in Fig. 5(d). The diffusivity and total absorption (D and C ∞ ) was determined by mathematical expression 5 based on the least squares fit, as illustrated in Fig. 5(d).

[0122]

[0123] Figure 6 is a diagram illustrating the hydrogen permeation and hydrogen leakage through a cylindrical EPDM polymer specimen versus time after pressurization. Volumetric analysis of the gas permeating the specimen using a gas permeation device was used to detect hydrogen permeation through the specimen and hydrogen leakage due to failure. The results, shown in Figure 6, show real-time hydrogen permeation and leakage in moles of hydrogen versus time after pressurization for a cylindrical EPDM specimen. The hydrogen permeation was measured via diffusion from the specimen after it reached steady state. A small amount due to leakage due to failure of the specimen increased linearly over time.

[0124]

[0125] Fig. 7(a) shows the results of analyzing He gas in this embodiment, Fig. 7(b) shows the results of analyzing N2 gas in this embodiment, Fig. 7(c) shows the results of analyzing O2 gas in this embodiment, and Fig. 7(d) shows the results of analyzing Ar gas in this embodiment. As with the H2 sensor described as an example above, a gas sensor applying the same principle was utilized to detect the diffusivity and permeability values ​​of other gases in the polymer. The principle and process of detecting the gas are exactly the same regardless of the gas species with different molar masses of the gas. For example, the molar mass of N2 gas is 28.001 g / mol. To demonstrate the sample application, the corresponding gas absorption (charging) and diffusivity values ​​of He, N2, O2, and Ar for the polymer sample are as shown.

[0126]

[0127] The gas diffusion rate in stainless steel is typically 10 at room temperature. -15 m 2 / s, and the gas adsorption capacity of this material is lower than that of polymer samples. Therefore, measuring the permeation parameters of other materials has been challenging. However, using the newly developed, highly sensitive sensor system, we have demonstrated that gas diffusion can be measured and analyzed even in metal plates as thin as 0.1 mm.

[0128]

[0129] While the present invention has been described with reference to the embodiments illustrated in the drawings to aid understanding, these are merely exemplary embodiments for practical purposes. Those skilled in the art will understand that various modifications and equivalent alternative embodiments are possible. Therefore, the true technical protection scope of the present invention should be defined by the appended claims.

Claims

1. A device for analyzing gas loaded into a sample, said device: A sample chamber in which the sample filled with the above gas is placed, and a cylinder extending in one direction from the sample chamber so that a portion of the cylinder is filled with a fluid; A transparent conductive electrode surrounding the outer periphery of the cylinder and extending in the one direction; a center electrode positioned at the center of the cylinder and extending in the one direction; and A capacitance detector that detects the capacitance value of the capacitor formed by the level of the fluid in the cylinder due to the gas released from the sample; and Contains a computing device, The above computing device, An analysis device that analyzes the gas charged into the sample from the above capacitance value.

2. In paragraph 1, The above transparent conductive electrode is, An analytical device comprising any one of ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), Graphene, Silver Nanowire, and CNT (Carbon Nano Tube).

3. In paragraph 1, The above center electrode is, An analytical device comprising a conductive metal wire comprising any one of copper wire, aluminum wire, and stainless steel wire.

4. In paragraph 1, The above sample room is, Having an outer circumference larger than the outer circumference of the above cylinder to accommodate the above sample, An analysis device further comprising a sealing member and a cover member for sealing the cylinder.

5. In paragraph 1, The above computing device, Mathematical formula An analysis device that calculates the water level (h) by calculating the water level. L: one-way length of the capacitor, R1: radius of the center electrode, R2: inner radius of the transparent conductive coaxial electrode as the outer electrode, and ε 0: Permittivity of free space, ε w : Permittivity of the fluid, ε g : dielectric constant of gas) 6. In paragraph 5, The above computing device, An analytical device for calculating the volume of gas released from the sample from a second-order polynomial equation for the correlation between the water level and capacitance obtained through quadratic regression.

7. In paragraph 6, The above calculation device calculates the number of moles of the gas released from the sample from the volume of gas released from the calculated sample, and the number of moles of the gas is calculated by the mathematical formula A method of performing a calculation. (T0: Initial temperature of the gas inside the cylinder, P0: Initial pressure of the gas inside the cylinder, V A : Initial residual air volume, V H (t): Volume of gas released, V(t)=V A + V H (t), n A is the initial air mole number, n H (t) is the number of moles of gas released) 8. In paragraph 7, The above computing device, The gas concentration of the gas released from the sample is calculated, and the concentration of the gas (C(t)) is expressed by the mathematical formula A method of performing a calculation. (m H [g / mol]: Molar mass of gas released from the sample, m sample is the mass of the sample) 9. In paragraph 8, A method further comprises a step of obtaining the gas diffusion coefficient of the sample, wherein the step of obtaining the gas diffusion coefficient (D) comprises: Mathematical formula A method of performing a calculation. (β n: Root of zero-order Bessel function J0(βn), D: diffusion coefficient, C ∞ : gas absorption of the sample, l: thickness of the sample, ρ: radius of the sample) 10. A device for analyzing a gas passing through a sample, said device comprising: A gas permeator comprising an inlet for introducing gas, a sealed sample chamber in which a sample is placed, and an outlet for discharging gas that has permeated the sample; A cylinder extending in one direction, partly filled with fluid, into which gas permeated from said sample flows; A transparent conductive electrode surrounding the outer periphery of the cylinder and extending in the one direction; A center electrode positioned at the center of the cylinder and extending in the one direction; A capacitance detector that detects the capacitance value of the capacitor formed by a change in the level of the fluid in the cylinder due to the gas that has passed through the sample; and Contains a computing device, The above computing device, An analysis device that analyzes gas passing through the sample based on the capacitance value.

11. In paragraph 10, The above gas permeator, A first member having an inlet through which high-pressure gas flows in; A sample room in which the above sample is placed; A sealing member sealing the above sample room and An analysis device including a second member having an outlet through which gas passing through the sample flows out.

12. In paragraph 10, The above transparent conductive electrode is, An analytical device comprising any one of ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), Graphene, Silver Nanowire, and CNT (Carbon Nano Tube).

13. In paragraph 10, The above center electrode is, An analytical device comprising a conductive metal wire comprising any one of copper wire, aluminum wire, and stainless steel wire.

14. In paragraph 10, The above computing device, Mathematical formula An analysis device that calculates the water level (h) by calculating the water level. L: one-way length of the capacitor, R1: radius of the center electrode, R2: inner radius of the transparent conductive coaxial electrode as the outer electrode, and ε 0: Permittivity of free space, ε w : Permittivity of the fluid, ε g : dielectric constant of gas) 15. In paragraph 14, The above computing device, An analytical device for calculating the volume of gas released from the sample from a second-order polynomial equation for the correlation between the water level and capacitance obtained through quadratic regression.

16. In paragraph 15, The above calculation device calculates the number of moles of the gas released from the sample from the volume of gas released from the calculated sample, and the number of moles of the gas is calculated by the mathematical formula A method of performing a calculation. (T0: Initial temperature of the gas inside the cylinder, P0: Initial pressure of the gas inside the cylinder, V A : Initial residual air volume, V H (t): Volume of gas released, V(t)=V A + V H (t), n A is the initial air mole number, n H (t) is the number of moles of gas released) 17. In paragraph 16, The above computing device, The gas concentration of the gas released from the sample is calculated, and the concentration of the gas (C(t)) is expressed by the mathematical formula A method of performing a calculation. (m H [g / mol]: Molar mass of gas released from the sample, m sample is the mass of the sample) 18. In paragraph 17, A method further comprises a step of obtaining the gas diffusion coefficient of the sample, wherein the step of obtaining the gas diffusion coefficient (D) comprises: Mathematical formula A method of performing a calculation. (β n: Root of zero-order Bessel function J0(βn), D: diffusion coefficient, C ∞ : gas absorption of the sample, l: thickness of the sample, ρ: radius of the sample) 19. In paragraph 18, The gas permeability of the above sample is calculated by the mathematical formula An analysis device that operates with . (A: gas contact area of the sample in the gas permeator, ΔP: pressure gradient difference between the supply side and the permeate side in the gas permeation, l: thickness of the sample, Δn / Δt: moles of permeate gas per hour)

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