KR102107929B1 - Hydroquinone-resorcinol clathrate compounds and a method for capturing or storing small atoms and molecules using the same - Google Patents

Abstract

The present invention relates to a hydroquinone-resosinol complex inclusion compound and a low molecular gas capture or storage method using the same. More specifically, the present invention relates to a hydroquinone-resosinol complex inclusion compound capable of capturing and storing low molecular gas at normal temperature and pressure, and a low molecular gas capture or storage method using the same. The hydroquinone-resosinol composite inclusion compound of the present invention can synthesize small-sized gas molecules into an inclusion body using low pressure, can have a high gas storage capacity, and has an effect of maintaining the gas storage performance even under normal pressure or normal temperature.

Description

Hydroquinone-resorcinol complex inclusion compound and low molecular gas capture or storage method using same {Hydroquinone-resorcinol clathrate compounds and a method for capturing or storing small atoms and molecules using the same}

The present invention relates to a hydroquinone-resosinol complex inclusion compound and a method for capturing or storing a low molecular gas using the same, and specifically, a hydroquinone-resosinol complex inclusion compound capable of capturing and storing a low molecular gas at room temperature and pressure. It relates to a method for capturing or storing low-molecular gas using the same.

Hydroquinone is one of phenols called quinone and is an aromatic organic compound. It is a structure in which two hydroxy groups are attached to the para position of the benzene ring and has isomers such as catechol and resorcinol depending on the position. Hydroquinone is produced by oxidizing aniline to produce quinone and then reducing it with nitrous acid, and is used for various purposes mainly related to acting as a reducing agent by dissolving in water.

Hydroquinone can act as a gas carrier by reacting with high pressure gas. Hydroquinone is largely classified into three crystal structures: an alpha-type structure that is stable in the atmospheric environment, a beta-type structure that can enclose small object molecules in a pupil structure composed of hydrogen bonds between hydroquinones, and a gamma-type obtained through sublimation. There is a structure. Among them, the beta-type structure having the inclusion compound is composed of hydrogen-bonded organic frameworks (HOFs) having a pupil structure capable of inclusion of large and small hydrocarbons, and a hexagonal c-axis passage in the hydroquinone molecule forming a hydrogen bond. It has a 1D channel structure that allows small molecules to enter and exit. The pupil diameter of the beta-type structure is approximately 4 mm 2, and it is known to have one pupil structure per three molecules of hydroquinone.

The hydroquinone inclusion compound has a great advantage that it is easy to synthesize and can be stored in an atmospheric environment. Accordingly, 'Republic of Korea Patent Publication No. 10-2013-0097561' discloses a method for separating carbon dioxide from a mixed gas using a hydroquinone inclusion compound and a method for confirming the same, but H ₂ , He, and D, which are frequently used in industry, are disclosed. There is no disclosure of inclusion of small-sized molecules such as ₂ and the like. In the case of small-sized molecules such as H ₂ , He, and D ₂ , a high pressure condition is required in order to be enclosed in hydroquinone, and thus, inclusion is difficult.

Further, according to the existing literature, the formation of a hydrogen hydroquinone inclusion compound having a β-form structure is possible (JL Daschbach, T.-M. Chang, R. Corrales, LX Dang, P. McGrail, J. Phys.Chem .B 2006, 110, 17291) Difficulties requiring an ultra-high pressure environment above 200 MPa (TA Strobel, Y. Kim, CA Koh, ED Sloan, 6th International Conference on Gas Hydrates (Eds .: J. Ripmeester, P. Englezos), Vancouver, 2008, p. 138). In particular, it has been shown that the compounds prepared in this way cannot be stably stored at normal temperature and pressure (JH Yoon, YJ Lee, J. Park, T. Kawamura, Y. Yamamoto, T. Komai, S. Takeya, SS Han, J .-W. Lee, and Y. Lee, ChemPhysChem 2009, 10, 352).

KR 10-2013-0097561

 Stabilization of Hydroquinone with Polyalcohols, Master's Thesis, Soongsil University Graduate School, 2013.02

In order to solve the above problems, an object of the present invention is to provide a low-molecular gas storage method of a hydroquinone-resosinol complex inclusion compound.

In addition, an object of the present invention is to provide a hydroquinone-resosinol complex inclusion compound for capturing or storing low molecular gas.

The present invention to solve the above object,

Dissolving hydroquinone and resorcinol in ethanol to produce a solution;

Degassing the residual gas by sealing the solution; And

It provides a low-molecular gas storage method of a hydroquinone-resorcinol complex inclusion compound comprising ;; by applying a pressure by applying a low-molecular gas to the degassed lysate.

The low molecular gas stored in the hydroquinone-resosinol complex inclusion compound is 0.3 to 2.4 molecules per 3 molecules of hydroquinone.

In addition, the low molecular gas is at least one selected from the group consisting of hydrogen, helium, deuterium, tritium, helium-3, and neon.

Hydroquinone has one pupil structure per three molecules.

Hydroquinone, resorcinol, and ethanol are mixed in a weight ratio of 4-8: 2-6: 13-21.

Hydroquinone and resorcinol are dissolved in ethanol and recrystallized.

The present invention to solve the above other object,

Hydroquinone and resorcinol,

It provides a hydroquinone-resosinol complex inclusion compound for capturing or storing low-molecular gas containing a hydrogen bonded organic framework having a pupil structure having a β-type structure.

The low molecular gas is one or more selected from the group consisting of hydrogen, helium, deuterium, tritium, helium-3, and neon.

In addition, the low molecular gas stored or captured in the hydroquinone-resosinol complex inclusion compound is 0.3 to 2.4 molecules per 3 molecules of hydroquinone.

The present invention provides a hydroquinone-resosinol complex inclusion compound and a method for capturing or storing a low-molecular gas using the same, so that a small-sized gas molecule can be synthesized in an inclusion body using a low pressure, and has a high gas storage capacity. , Even at a normal pressure or a normal temperature, there is an effect that can maintain the gas storage performance.

1 is a graph showing the XRD results of a hydroquinone-resosinol inclusion compound prepared according to an embodiment of the present invention.
2 is a graph showing the XRD results of a hydroquinone inclusion compound prepared according to a comparative example of the present invention.
3 is a graph showing Raman spectroscopy results of a hydroquinone-resosinol inclusion compound prepared according to an embodiment of the present invention.
4 is a graph showing Raman spectroscopy results of a hydroquinone inclusion compound prepared according to a comparative example of the present invention.

Hereinafter, the present invention will be described in detail.

In the present specification, when a part “includes” a certain component, it means that the component may further include other components, not to exclude other components, unless otherwise stated.

According to an aspect of the present invention, the step of dissolving hydroquinone and resorcinol in ethanol to produce a solution; Degassing the residual gas by sealing the solution; It provides a low-molecular gas storage method of a hydroquinone-resorcinol complex inclusion compound comprising ;; and applying a pressure to the degassed dissolved solution by applying a low-molecular gas to the pressure to generate the inclusion compound is stored gas.

Hydroquinone and resorcinol have something in common called phenols, and resorcinol is an isomer of hydroquinone. That is, hydroquinone and resorcinol are compounds having the same molecular formula but not the same connection method or spatial arrangement of members in the molecule. Therefore, even if the molecular formula is the same, isomers have a characteristic that at least one of chemical or physical properties is different, and resorcinol can be said to be a completely different compound from hydroquinone.

The gas storage performance of the hydroquinone-resosinol composite inclusion compound can be confirmed by the weight percent of the low molecular gas or the inclusion ratio of the pupil. The low molecular gas stored in the hydroquinone-resosinol complex inclusion compound may be 0.3 to 2.4 molecules per 3 molecules of hydroquinone. This means that one to three gas molecules can be enclosed in one pupil. In addition, the inclusion rate of the hydroquinone-resosinol composite inclusion compound pupil may be 30% to 240%.

The low molecular gas may be one or more selected from the group consisting of hydrogen, helium, deuterium, tritium, an isotope of hydrogen, helium-3, an isotope of helium, and neon. Hydrogen, helium, deuterium, and neon are frequently spotlighted as the next generation of energy sources for gases frequently used by industries, but they are not easily utilized due to the demanding conditions such as high pressure or low temperature for efficient storage and transportation. This is a necessary situation.

In addition, hydroquinone is characterized by having one pupil structure per three molecules. The pupil diameter of the hydroquinone β-type structure is approximately 1 to 4 mm 2, and the pore structure can encapsulate large and small hydrocarbons.

Hydroquinone is a colorless needle crystal having an α-structure, which is an initial pure structure, and when an object molecule is enclosed in hydroquinone, a structure change to β-structure occurs. There are various types of gas molecules as object molecules, and it is possible to selectively separate and recover objects according to mixing conditions and forming pressure. Hydroquinone is a suitable material as a carrier of gas because it maintains a state of inclusion of gas at atmospheric pressure and atmospheric temperature for a certain period of time when the clathrate is formed in a high-pressure environment. The gas can be easily separated again by dissolving it in alcohol or heating it.

In the method for storing a low molecular gas of a hydroquinone-resorcinol complex inclusion compound, hydroquinone, resorcinol, and ethanol may be mixed in a weight ratio of 4-8: 2-6: 13-21, preferably 5 -7: 3-5: 14-19 can be mixed in a weight ratio. At this time, ethanol solution is injected into hydroquinone and resorcinol to be mixed in a supersaturated state.

According to another aspect of the present invention, a hydroquinone for capturing or storing a low-molecular gas comprising a hydrogen bonded organic framework having a pupil structure by showing a structure of β-type, including hydroquinone and resorcinol, -Provides a resorcinol complex inclusion compound.

The low molecular gas may be one or more selected from the group consisting of hydrogen, helium, deuterium, tritium, an isotope of hydrogen, helium-3, an isotope of helium, and neon. Hydrogen, helium, deuterium, and neon are frequently used gases in the industry and are in the spotlight as the next generation energy sources of the future.

The gas storage performance of the hydroquinone-resosinol composite inclusion compound can be confirmed by the weight percent of the low molecular gas or the inclusion ratio of the pupil. The low molecular gas stored in the hydroquinone-resosinol complex inclusion compound may be 0.3 to 2.4 molecules per 3 molecules of hydroquinone. This means that one to three gas molecules can be enclosed in one pupil. In addition, the inclusion rate of the hydroquinone-resosinol composite inclusion compound pupil may be 30% to 240%.

In the present invention, it is possible to confirm whether gas inclusion is possible by confirming the structure of the β-type structure of the hydroquinone-resorcinol complex inclusion compound using X-ray diffraction (XRD), and Raman spectroscopy. , It is possible to confirm the amount of gas stored in the inclusion compound by a gravimetric method for measuring the weight of the gas.

The inclusion compound of the present invention has great significance in maintaining gas storage under normal pressure and normal temperature. In addition, the present invention provides a method for synthesizing a gas molecule of a small size with a β-form hydroquinone structure capable of having a high gas storage amount, and a synthesized sample is compared with a known hydroquinone inclusion compound. Excellent gas storage performance.

Hereinafter, examples will be described in detail to specifically describe the present specification. However, the embodiments according to the present specification may be modified in various other forms, and the scope of the present specification is not construed as being limited to the embodiments described below. The embodiments of the present specification are provided to more fully describe the present specification to those skilled in the art.

<Example>

Example 1. Preparation of hydroquinone-resorcinol inclusion compound and hydrogen inclusion

Hydroquinone and resorcinol were dissolved in ethanol in a saturated state by setting the weight ratio of hydroquinone: resorcinol: ethanol to 6: 4: 16.5. After the mixing was completed, the hydroquinone-resosinol ethanol solution was placed in a vial and then inserted into a high-pressure reaction cell having an internal volume of 55 ml. After the high-pressure reaction cell was closed, the residual gas inside the cell was degassed using a vacuum pump, and then hydrogen was added at a pressure of 10 Mpa. After completion of the gas injection, the cell containing the solution was reacted at -20 ° C for 12 hours to recrystallize the hydroquinone-resorcinol that encapsulated the gas. The internal pressure was then removed and the crystals were filtered out using a 45 μm sieve.

Example 2. Preparation of hydroquinone-resosinol inclusion compound and helium inclusion

Hydroquinone and resorcinol were dissolved in ethanol in a saturated state by setting the weight ratio of hydroquinone: resorcinol: ethanol to 6: 4: 16.5. After the mixing was completed, the hydroquinone-resosinol ethanol solution was placed in a vial and then inserted into a high-pressure reaction cell having an internal volume of 55 ml. After the high pressure reaction cell was closed, the residual gas inside the cell was degassed using a vacuum pump, and then helium was applied at a pressure of 10 Mpa. After completion of the gas injection, the cell containing the solution was reacted at -20 ° C for 12 hours to recrystallize the hydroquinone-resorcinol that encapsulated the gas. The internal pressure was then removed and the crystals were filtered out using a 45 μm sieve.

Example 3. Preparation of hydroquinone-resosinol inclusion compound and deuterium inclusion

Hydroquinone and resorcinol were dissolved in ethanol in a saturated state by setting the weight ratio of hydroquinone: resorcinol: ethanol to 6: 4: 16.5. After the mixing was completed, the hydroquinone-resosinol ethanol solution was placed in a vial and then inserted into a high-pressure reaction cell having an internal volume of 55 ml. After the high-pressure reaction cell was closed, the residual gas inside the cell was degassed using a vacuum pump, and then deuterium was applied at a pressure of 10 Mpa. After completion of the gas injection, the cell containing the solution was reacted at -20 ° C for 12 hours to recrystallize the hydroquinone-resorcinol that encapsulated the gas. The internal pressure was then removed and the crystals were filtered out using a 45 μm sieve.

Example 4. Preparation of hydroquinone-resosinol inclusion compound and neon inclusion

Hydroquinone and resorcinol were dissolved in ethanol in a saturated state by setting the weight ratio of hydroquinone: resorcinol: ethanol to 6: 4: 16.5. After the mixing was completed, the hydroquinone-resosinol ethanol solution was placed in a vial and then inserted into a high-pressure reaction cell having an internal volume of 55 ml. After the high-pressure reaction cell was closed, the residual gas inside the cell was degassed using a vacuum pump, and then neon was applied at a pressure of 10 Mpa. After completion of the gas injection, the cell containing the solution was reacted at -20 ° C for 12 hours to recrystallize the hydroquinone-resorcinol that encapsulated the gas. The internal pressure was then removed and the crystals were filtered out using a 45 μm sieve.

Comparative Example 1. Preparation of hydroquinone inclusion compound and hydrogen inclusion

The hydroquinone was crushed to a size of 20 μm or less and inserted into a single crystal sapphire reactor connectable to a high pressure fitting. Subsequently, hydrogen was applied to the inside of the reactor at a pressure of 12 MPa to react hydroquinone and hydrogen for 24 hours, and a hydroquinone inclusion compound containing hydrogen was obtained through this reaction.

<Experimental Example>

Experimental Example 1-Confirmation of crystal structure of hydroquinone-resosinol inclusion compound (XRD)

The crystal structures of the hydroquinone-resorcinol inclusion compounds prepared in Examples 1 to 4 and the hydroquinone inclusion compounds prepared in Comparative Example 1 were analyzed using X-ray diffraction (XRD). After crushing the hydroquinone-resosinol inclusion compound in the crystalline form obtained in Examples 1 to 4 and Comparative Example 1 to a size of 100 μm or less, the sample holder was filled and the sample holder was mounted on the XRD equipment. . The XRD equipment was measured under the following conditions to confirm the crystal structure. Measured at a temperature of 300 K (at room temperature) and vacuum pressure, the light source type is Bending Magnet, the energy range is 8 to 20 keV, the beam intensity is ~ 10 ¹¹ photons / s, and the wavelength is 1.51 Å. The sample was irradiated, and the theta 12.5 degree detector was set to 25 degrees using the 2theta scan mode, and 6 detectors were measured at 20 degrees each, and the process of measuring from 5 degrees to 125.5 degrees at 0.01 degree intervals was performed.

Experimental Example 2-Confirmation of crystal structure of hydroquinone-resosinol inclusion compound (Raman)

The peaks were observed using Raman spectroscopy to confirm each crystal structure of the hydroquinone-resosinol inclusion compounds prepared in Examples 1 to 4. It was measured in an environment of 300 K temperature (at room temperature) and normal pressure, and the measurement sample was measured by placing the hydroquinone-resosinol inclusion compound obtained in Examples 1 to 4 on a sample plate without pretreatment. An excitation signal was generated using an argon ion laser of 514 nm having an intensity of 71 mW, and the generated signal was recorded at a resolution of 1 cm ⁻¹ .

Experimental Example 3-Confirmation of gas storage performance of hydroquinone-resosinol inclusion compounds

Gravimetric method was used to confirm the gas storage performance of each of the hydroquinone-resosinol inclusion compounds prepared in Examples 1 to 4. The hydroquinone-resosinol inclusion compound has a characteristic of releasing gas when heat is applied, and it is possible to confirm the amount of stored gas when it is heated to release the gas.

After measuring the weight of the hydroquinone-resosinol inclusion compound synthesized with each gas in Examples 1 to 4, each sample was put in a glass vial and heated at 140 ° C. for 24 hours with a hot plate. At this time, in order to prevent the weight reduction by hydroquinone and resorcinol having the characteristics of sublimation, the vial contains a sample of the vial and stacks the glass beads washed thereon to sublimate the hydroquinone and resorcinol sublimated due to the difference in thermal conductivity. I was locked up. The amount of gas initially stored was calculated by measuring the weight of the hydroquinone-resosinol inclusion compound whose weight was stopped after 24 hours.

Experimental Example 4-Confirmation of the crystal structure of the hydroquinone inclusion compound (XRD)

The crystal structure of the hydroquinone inclusion compound prepared according to Comparative Example 1 was confirmed by XRD analysis at a pressure of 12 MPa and room temperature without releasing the pressure of the reactor. The conditions of XRD equipment are as follows. The light source type is an In-vacuum Undulator 20, the energy range is 5 ~ 16 keV, the beam intensity is ~ 10 ¹³ photons / s, and a wavelength of 0.6927 Å is irradiated to the sample, using the 2theta scan mode, 2 The process of measuring the dimensional X-ray scattering pattern continuously and measuring up to 30 degrees was performed.

Experimental Example 5-Confirmation of crystal structure of hydroquinone inclusion compound (Raman)

The crystal structure of the hydroquinone inclusion compound prepared according to Comparative Example 1 was confirmed through Raman analysis under a pressure of 12 MPa and a room temperature condition without releasing the pressure of the reactor. An excitation signal was generated using an argon ion laser of 514 nm having an intensity of 71 mW, and the generated signal was recorded at a resolution of 1 cm ⁻¹ .

Experimental Example 6-Confirmation of the gas storage performance of the hydroquinone inclusion compound

A magnetic scale was used to evaluate the hydrogen storage capacity of the hydroquinone inclusion compound prepared according to Comparative Example 1. To remove impurities and moisture, the container containing the sample was vacuumed for 24 hours at 508 ° C. and 106 Torr. The hydrogen storage performance of the sample was then evaluated by monitoring the sample mass change in the vessel and taking into account the buoyancy of the sample.

<Evaluation and results>

Result 1-Crystal structure confirmation result (XRD)

The crystal structure of the hydroquinone-resorcinol inclusion compound prepared according to Example 1 and the hydroquinone inclusion compound prepared according to Comparative Example was confirmed using XRD, and the results are shown in FIGS. 1 to 2.

As a result of the structural analysis, it was confirmed that the crystal structure of the compound according to Example 1 had a hydroquinone β-form structure of rhombohedral space group R-3 and a = b = 16.6 Å and c = 5.5 의 in the hexagonal direction. This means that α-form hydroquinone has been converted to a β-form structure through synthesis with a low-molecular gas. On the other hand, it was confirmed that the hydroquinone inclusion compound of the comparative example has a = 38.5 Å and c = 5.7 으로 as a space group R3 having an α-form structure. The ratio of the hydroquinone molecule having the β-form structure of the present invention and the pupil capable of enclosing the gas is 3: 1, and the maximum storage potential of gas is superior when compared with 18: 1 of the comparative example α-form structure.

Result 2-Crystal structure confirmation result (Raman)

The crystal structure of the hydroquinone-resorcinol inclusion compound prepared according to the above example and the hydroquinone inclusion compound prepared according to the comparative example was confirmed using Raman spectroscopy, and the results are shown in FIGS. 3 to 4.

Compared with the characteristic peak shape of the known hydroquinone β-form structure, it was confirmed that the hydroquinone-resorcinol inclusion compound of Example 1 is a hydroquinone β-form structure, and the Raman peak characteristic of the main β-form structure is It is as follows. The peak near 1160 cm ^-1 by CH in-plane bending mode was divided into two peaks in α-HQ, but one peak in β-HQ. In addition, it was confirmed that one major peak due to the CO and CC stretching mode near 1250 cm ^-1 and the triplet-shaped band near 1600 cm ^-1 , which are the main characteristics of the β-HQ structure.

On the other hand, it was also confirmed through Raman spectroscopy that the hydroquinone inclusion compound of the comparative example has a peak characteristic of hydroquinone α-form.

Result 3. Gas storage performance confirmation result

The gas storage performance of the hydroquinone-resorcinol inclusion compound prepared according to Examples to Comparative Examples was confirmed, and the results are shown in Table 1 below.

cm ³ (gas) / g (HQ) wt% L (gas) / L (HQ) g (gas) / L (HQ) Inclusion rate
(number of gas molecule / 3HQ) Example H ₂ 165.87 1.45 211.32 18.76 2.41 D ₂ 108.45 1.89 138.16 24.50 1.58 He 95.28 1.67 121.39 21.68 1.40 Ne 25.63 2.23 32.65 29.01 0.37 Comparative example H ₂ 5.64 0.05 7.19 0.64 0.08

In the case of H ₂ , He, Ne, it has been known that it can be stable at room temperature and pressure by forming α-form hydroquinone when synthesized with hydroquinone, but it can induce hydroquinone molecules and gases in the α-form structure. The pupil ratio is 18: 1, and the maximum storage probability is relatively lower than the 3: 1 of the β-form structure of the present invention. In the α-form structure, assuming that each gas fills all the pupils, H ₂ = 0.10 wt%, He = 0.20 wt%, Ne = 1.02 wt%, D ₂ = 0.20 wt%, and the hydrogel of the comparative example As the hydrogen storage performance of the quinone inclusion compound was 0.05 wt%, the actual storage performance shows a lower value. On the other hand, the gas storage performance of the hydroquinone-resosinol inclusion compounds according to the embodiment having a β-form structure is H ₂ = 1.45 wt%, He = 1.67 wt%, Ne = 2.23 wt%, D ₂ = 1.89 wt% It will have a weight ratio, and it can be confirmed that the hydroquinone α-form structure is significantly improved.

Claims (9)

Dissolving hydroquinone and resorcinol in ethanol to produce a solution;
Degassing the residual gas by sealing the solution; And
A method for storing a low molecular gas of a hydroquinone-resorcinol complex inclusion compound comprising the steps of: applying a pressure to the degassed solution to inject a low molecular gas to generate an inclusion compound in which the gas is stored. According to claim 1,
A method for storing a low molecular gas in a hydroquinone-resosinol complex inclusion compound, wherein the low molecular gas stored in the hydroquinone-resosinol complex inclusion compound is 0.3 to 2.4 molecules per 3 molecules of hydroquinone. The method according to claim 1 or 2,
The low molecular gas is hydrogen, helium, deuterium, tritium, helium-3, and a method for storing a low molecular gas of a hydroquinone-resosinol complex inclusion compound, characterized in that at least one selected from the group consisting of neon. According to claim 1,
The hydroquinone is a method for storing a low molecular gas of a hydroquinone-resorcinol complex inclusion compound, characterized in that it has one pupil structure per three molecules. According to claim 1,
The hydroquinone, resorcinol, and ethanol is a method of storing a low molecular gas of a hydroquinone-resorcinol complex inclusion compound, characterized in that it is mixed in a weight ratio of 4-8: 2-6: 13-21. According to claim 1,
The hydroquinone and resorcinol is dissolved in ethanol and recrystallized, characterized in that the hydroquinone-resorcinol composite low molecular gas storage method of the inclusion compound. Hydroquinone and resorcinol,
Hydroquinone-resorcinol complex inclusion compound for capture or storage of low-molecular gas containing a hydrogen bonded organic framework having a pupil structure exhibiting a β-type structure. The method of claim 7,
The low molecular gas is hydrogen, helium, deuterium, tritium, helium-3, and a hydroquinone-resosinol complex inclusion compound for the capture or storage of low molecular gas, characterized in that at least one selected from the group consisting of neon. The method of claim 7,
The low molecular gas stored or captured in the hydroquinone-resosinol complex inclusion compound is a hydroquinone-resosinol complex inclusion compound for capture or storage of low molecular gas, characterized in that 0.3 to 2.4 molecules per 3 molecules of hydroquinone.

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