KR20100085285A - Method for purification of hydrogen gas - Google Patents

Abstract

PURPOSE: A purification method of hydrogen gas is provided to reduce processing costs and to improve hydrogen refining efficiency by refining a large amount of hydrogen gas within a rapid time. CONSTITUTION: A purification method of hydrogen gas removing impurities from the hydrogen gas includes a step for removing impurities by passing the hydrogen gas including impurities consisting of a hydrocarbon-based material, boron, phosphorus or a mixture thereof through an adsorption layer filled with an adsorbent(2). A molecular sieve is made of a carbon molecular sieve, a molecular sieve of zeolite, a molecular sieve of silica or an alumina molecular sieve.

Description

Hydrogen Gas Purification Method (Ⅰ) {Method for Purification of Hydrogen Gas}

The present invention relates to a method for purifying hydrogen gas, and more particularly, to pass hydrogen gas containing impurities, in particular impurities consisting of a hydrocarbon-based material, boron, phosphorus or a mixture thereof, through an adsorbent in the form of a molecular sieve at low temperature. The present invention relates to a hydrogen gas purification method for removing impurities.

Hydrogen gas is mainly used to manufacture silicon as a semiconductor raw material in the semiconductor manufacturing industry, which has grown at an enormous scale, and is widely used as various atmosphere gases in semiconductor manufacturing using silicon.

Recently, with the improvement of the integration of semiconductors, the demand for improving the purity of silicon and the purity of hydrogen gas is increasing, and in order to reduce the process cost and raw material cost, it is necessary to purify and reuse the hydrogen gas used in the silicon manufacturing process. The need is increasing.

For this reason, impurities in the hydrogen gas can be efficiently removed by removing hydrocarbon-based materials and / or inorganic impurities containing boron and phosphorus or inorganic impurities in the form of hydrogen compounds including boron hydride and phosphorus hydride. There is an urgent need for purification to exist in ppb units or less.

As an example of such a method for purifying hydrogen gas, US Pat. No. 3,992,167, US Pat. No. 4,242,875, US Pat. No. 4,043,770, US Pat. No. 4,099,936 and Korean Patent Publication No. 1989-0004761 purify hydrogen gas at low temperature. A method of purifying hydrogen gas using a pressure swing adsorption method using an adsorbent is disclosed in WO 2002/004096, and WO 2006/043696 and Korean Patent Publication No. 2007. -0070133 discloses a purification method for selectively permeating hydrogen using a metal separator.

In addition, as another method for purifying hydrogen gas, a method of purifying hydrogen gas by adsorption at room temperature by combining a chemical reaction by a metal catalyst such as nickel and physical adsorption by an adsorbent such as synthetic zeolite is known.

Here, the method for purifying hydrogen gas at a low temperature state is a method of adsorbing and removing impurities using physical adsorption properties of an adsorbent at low temperature using a cold heat source such as liquid nitrogen, which is commonly referred to as a deep cold adsorption method. However, this method has an advantage of almost removing impurities including hydrocarbons and nitrogen contained in hydrogen gas at higher efficiency than using an adsorbent at room temperature.

However, the above-mentioned deep cold adsorption method requires cooling the hydrogen gas to cryogenic temperature by using a cold heat source such as liquid nitrogen, and thus there is a problem of excessive cooling cost.

On the other hand, the pressure swing adsorption method of purifying hydrogen gas by pressure swing method using an adsorbent has the advantage of purifying a large amount of hydrogen at once, but it is inconvenient to apply when hydrogen gas flows in a continuous process. Etc.

In the method of purifying hydrogen gas using the metal separation membrane, in particular, the method of purifying hydrogen gas using a palladium alloy membrane utilizes the selective permeability of hydrogen gas, thereby removing all components present in the form of impurities except hydrogen to obtain ultra-high purity hydrogen gas. However, this is a problem that the apparatus cost per flow rate of purified gas increases due to the expensive metal membrane.

In addition, in the case of the room temperature adsorption method combining the chemical reaction of the metal catalyst and the physical adsorption of the adsorbent, the apparatus cost per flow rate of the purified gas is low, but it is difficult to remove hydrocarbons or nitrogen present in a relatively large amount in hydrogen gas easily. There is a problem.

As described above, in the purification of hydrogen gas to date, a device cost and operation cost per flow rate of purified gas are low, and a technique capable of safely purifying a large amount of hydrogen in high purity in a short time, or a small amount of hydrogen gas in ultra high purity Development of hydrogen gas refining technology that satisfies the conditions that can be purified as has been steadily progressed, but the development of technology that can satisfy all the above conditions to the maximum is still insufficient.

Thus, the present inventors have conducted research on hydrogen gas as well as other gas purification techniques to develop a technology that satisfies all of the above conditions. Research on the purification of silane and the purification of trichlorosilane gas used in the production of polysilicon, the method of removing impurities from the silane gas and the method of removing impurities from the trichlorosilane gas include silicon and / or semiconductor manufacturing. The present invention has been completed by focusing on the fact that the present invention can be applied by a method for removing impurities contained in hydrogen gas used in the process.

The present invention is a method for purifying hydrogen gas containing impurities consisting of hydrocarbon-based material, boron, phosphorus or a mixture thereof using a molecular sieve adsorbent by fusing the technology for purifying silane gas and trichlorosilane gas at low temperature. There is a problem to be solved in providing.

In particular, the method for purifying hydrogen gas removes impurities in hydrogen gas to be less than or equal to ppb by passing hydrogen gas containing impurities having a purity of ppm unit safely in a short time at low cost through a molecular sieve adsorbent at low temperature. There is a problem to be solved to provide a hydrogen gas purification method.

Here, in the case of phosphorus among the impurities contained in the hydrogen gas, it may be purified at a level of ppb unit or less, and in the case of carbon, to a level of ppm unit or less.

The present invention also provides a process for purifying impurities from hydrogen gas comprising impurities consisting of hydrocarbon-based materials, boron, phosphorus or mixtures thereof in a continuous process in large quantities, for example at least 500 kg per hour, preferably 700 kg per hour. There is a problem to be solved in providing.

The present invention is to adsorb and remove hydrogen gas containing impurities consisting of a hydrocarbon-based material, boron, phosphorus or a mixture thereof through a adsorption layer filled with an adsorbent in the form of a molecular sieve at a low temperature of -60 to -100 ° C. There is a problem solving means to provide a purification method for removing impurities from the hydrogen gas included.

In addition, the present invention is an inlet for the introduction of hydrogen gas containing impurities consisting of a hydrocarbon-based material, boron, phosphorus or a mixture thereof;

At least two filling towers connected to the inlet to maintain a low temperature of -60 to -100 ° C. to adsorb and remove impurities contained in hydrogen gas, and filled with an adsorbent in the form of a molecular sieve;

A discharge port connected to one side of the filling tower and passing through the filling tower to discharge purified hydrogen gas;

An injection valve connected between the at least two filling towers and the inlet, respectively, to open and close an inflow path of hydrogen gas including impurities introduced into the respective filling towers; And

It is connected between each of the at least two filling tower and the discharge port is provided with a hydrogen gas purification device for removing impurities from the hydrogen gas passing through each of the filling tower and including a discharge valve for opening and closing the discharge path of the purified hydrogen gas There is a problem solving means.

As described above, the method for purifying hydrogen gas according to the present invention not only has a lower process cost and lower operating cost than the conventional method for purifying hydrogen gas, but also has a higher purity, for example, less than or equal to ppb for boron and phosphorus, and for carbon. There is an effect that can purify the hydrogen gas in the purity of ppm unit or less.

In addition, the present invention has the effect that can be purified in a large number of hydrogen gas in a continuous process.

In one aspect, the present invention is a hydrogen gas containing an impurity consisting of a hydrocarbon-based material, boron, phosphorus or a mixture thereof through a adsorption bed filled with an adsorbent in the form of molecular sieve at a low temperature of -60 to -100 ℃ It provides a purification method for removing impurities from the hydrogen gas comprising the adsorption removal.

In another aspect, the present invention provides an inlet for introducing hydrogen gas containing impurities consisting of a hydrocarbon-based material, boron, phosphorus or a mixture thereof; At least two filling towers connected to the inlet to maintain a low temperature of -60 to -100 ° C. to adsorb and remove impurities contained in hydrogen gas, and filled with an adsorbent in the form of a molecular sieve; A discharge port connected to one side of the filling tower and passing through the filling tower to discharge purified hydrogen gas; An injection valve connected between the at least two filling towers and the inlet, respectively, to open and close an inflow path of hydrogen gas including impurities introduced into the respective filling towers; And a discharge valve connected between the at least two filling towers and the discharge port, respectively, and including a discharge valve passing through the respective filling towers to open and close the discharge path of the purified hydrogen gas. to provide.

Here, the adsorbents are impurities contained in hydrogen gas at low temperature, preferably -0 ° C, more preferably -60 to -100 ° C, specifically hydrocarbon-based materials, boron, phosphorus or mixtures thereof. Molecular sieves capable of adsorbing and removing the formed impurities are not particularly limited, but are preferably zeolite-based molecular sieves, and more preferably zeolite 4-A having a specific surface area of 300 to 1,000 m ² / g. It is good to be

At this time, the adsorbent is installed in the movement path of the hydrogen gas containing impurities, preferably a separate hydrogen gas movement path, preferably in the form of adsorbent is filled in the packing tower to form an adsorption layer. .

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. However, the following description is only for explaining the present invention specifically, and is not limited to the scope of the present invention by the following description.

1 is a schematic diagram of a hydrogen gas purifying apparatus according to the present invention.

As shown in FIG. 1, the hydrogen gas purifying apparatus according to the present invention includes an inlet port 4 through which hydrogen gas containing impurities consisting of a hydrocarbon-based material, boron, phosphorus, or a mixture thereof is introduced; It is connected to the inlet (4) is maintained at a low temperature of -60 to -100 ℃ to adsorb and remove impurities contained in the hydrogen gas, at least two or more packed column filled with an adsorbent in the form of a molecular sieve (6, 8, 10); A discharge port 24 connected to one side of the filling towers 6, 8, and 10, passing through the filling towers 6, 9, and 10 to discharge purified hydrogen gas; The at least two filling towers 6, 8, and 10 are respectively connected between the inlets 4 to open and close the inflow path of hydrogen gas including impurities introduced into the filling towers 6, 8, and 10. Injection valves 12, 14, and 16; And connected between the at least two or more filling towers 6, 8, 10 and the outlet 24, respectively, passing through each of the filling towers 6, 8, 10 and opening and closing the discharge path of the purified hydrogen gas. It consists of discharge valves 18, 20, and 22.

The inlet 4 according to the present invention is an inlet through which hydrogen gas containing impurities composed of hydrocarbon-based material, boron, phosphorus or a mixture thereof is introduced.

In this case, the hydrogen gas flowing into the inlet 4 is hydrogen gas used in a semiconductor manufacturing process, specifically, a semiconductor manufacturing process using silicon and / or a solar cell manufacturing process, and the semiconductor manufacturing process and / or a solar cell manufacturing. It is used in the process and contains impurities consisting of hydrocarbon-based materials, boron, phosphorus or mixtures thereof.

In a particular embodiment, the hydrogen gas purifying apparatus according to the present invention cools down the hydrogen gas containing impurities introduced into the inlet 4 at the front end of the inlet 4, preferably below -0 ° C., more preferably. Cooling means (not shown) is further provided for cooling below -60 ° C, particularly preferably in the range of -60 to -100 ° C, and hydrogen gas supplied to the filling towers 6, 8 and 10 filled with the adsorbent. It can be cooled to a temperature range with high adsorption efficiency.

In addition, the outlet 24 according to the present invention is purified after passing through the filling tower (6, 8, 10) the hydrogen gas containing impurities introduced into the inlet (4) or discharge to the outside or semiconductor manufacturing process and / Or to discharge to recycle to the solar cell manufacturing process.

Here, the inlet 4 and / or outlet 24 is provided with a separate opening and closing means 26, specifically opening and closing means 26, such as a valve to open the inlet 4 and / or outlet 24. By adjusting the degree, the internal pressure of the filling towers 6, 8 and 10 can be 2 to 110 kPa, preferably 100 to 110 kPa.

Filling tower (6, 8, 10) according to the present invention is for the adsorption and removal of impurities contained in the hydrogen gas passes through the hydrogen gas containing impurities introduced into the inlet (4), the filling tower for this purpose If it is (6, 8, 10), although it will not specifically limit, Preferably, it forms the inside of the adsorbent 2 in the form of molecular sieve, and it is formed so that an adsorption layer may be sealed, and hydrogen gas in which one end contains an impurity inflows. It is connected to the inlet (4) is installed, the outlet 24 for discharging the purified hydrogen gas is connected to the other end opposite to the one end is connected to the inlet (4) is installed.

At this time, the adsorbent (2) is not particularly limited as long as it is an adsorbent capable of adsorbing and removing impurities from hydrogen gas. It is preferable to use the adsorbent 2 having a molecular sieve form such as itself, more preferably an adsorbent having a molecular sieve form having an inorganic oxide structure, and particularly preferably a specific surface area of 300 as the zeolite-based molecular sieve. It is preferable to use a zeolite molecular sieve which is a zeolite 4-A having a zeolite of 4-1000 m ² / g, and it is recommended to have a pore size of 4 mm 3, a pore volume of about 47%, and a specific surface area of 300 to 1,0000 m ² / It is preferred to use an adsorbent 2 having a zeolite 4-A molecular sieve form of g.

In addition, in order to adsorb and remove impurities from hydrogen gas containing impurities made of a hydrocarbon-based material, boron, phosphorus or a mixture thereof by using the adsorbent 2, the temperature of the adsorption layer filled with the adsorbent is lowered, Specifically, it is preferable to keep the temperature at a low temperature of -60 to -100 ° C, and further, the internal pressure of hydrogen gas passing through the adsorption layer is at atmospheric pressure, preferably 2 to 110 kPa, more preferably 100 to 110 kPa. good.

In particular, efficient removal of impurities in hydrogen gas through actual adsorption is possible from low temperature below -0 ℃, and as the temperature is kept lower, the efficiency of removing impurities in hydrogen gas increases but process cost increases excessively. If it increases, there is a problem that the efficiency of removing impurities inside the hydrogen gas is too low.

In addition, the higher the pressure of the hydrogen when removing impurities in the hydrogen gas has the advantage that the efficiency of removing impurities. At this time, as the pressure increases, the adsorbed amount of impurities rapidly increases to 100 to 110 kPa, and it is known that the pressure does not increase significantly at higher pressures. Therefore, it is preferable to maintain the hydrogen adsorption temperature at -60 to -100 ° C while the pressure of the hydrogen gas is 100 to 110 kPa higher than atmospheric pressure.

At this time, the lower the temperature, the higher the pressure, the higher the removal efficiency of impurities contained in the hydrogen gas, but the temperature and pressure range is determined in consideration of the operating cost of the hydrogen gas purification device. good.

On the other hand, in addition to the cooling of the hydrogen gas containing impurities flowing into the inlet (4) for more efficient adsorption of the hydrogen gas containing the impurity separate from one side of the filling tower (6, 8, 10) or the outer peripheral surface Cooling means (not shown) may be further provided to maintain an appropriate temperature for adsorbing and removing hydrogen gas, for example, a temperature range of -60 to -100 ° C.

At this time, the cooling means is conventional in the art that can maintain the internal temperature of the filling tower (6, 8, 10) to -0 ℃ or less, preferably -60 ℃ or less, more preferably -60 to -100 ℃ Any phosphorus cooling means may be used.

In addition, the number of the filling tower (6, 8, 10) is not particularly limited, but may be installed in plurality, preferably three or more according to the user's choice.

On the other hand, in order to more easily explain the hydrogen gas purification apparatus according to the present invention, if the three filling towers (6, 8, 10) optionally installed in the hydrogen gas purification apparatus of the three filling tower (6, 8, 10) When one filling tower is optionally referred to as the first filling tower 6, the other filling tower is sequentially referred to as the second filling tower 8 and the other filling tower as the third filling tower 10. do.

In addition, all the filling towers (6, 8, 10) may be filled with the same adsorbent (2) in the same amount or the amount of use according to the user's choice, each of the filling towers (6, 8, 10) independently of each other It is connected to the inlet port 4 through which hydrogen gas containing impurities is introduced and the outlet port 24 through which purified hydrogen gas is discharged.

At this time, between the first filling tower 6, the second filling tower 8, and the third filling tower 10 and the inlet 4, the hydrogen gas containing impurities introduced through the inlet 4, respectively The first injection valve 12, the second injection valve 14, and the third injection valve 16 are opening / closing means for controlling the inflow into the filling towers 6, 8, and 10, respectively. 8, 10) is installed.

In addition, to control the movement of the purified hydrogen gas discharged through the outlet 24 between the first filling tower (6), the second filling tower (8) and the third filling tower (10) and the outlet (24). As opening and closing means for the first discharge valve 18, the second discharge valve 20 and the third discharge valve 22 is installed in each of the filling tower (6, 8, 10).

Referring to the operation of the hydrogen gas purification apparatus according to the present invention having such a configuration as follows.

First, when hydrogen gas containing impurities including hydrocarbon-based materials, boron, phosphorus, or a mixture thereof is generated, used in a semiconductor manufacturing process and / or a solar cell manufacturing process, it is introduced into the inlet 4.

At this time, the hydrogen gas containing impurities introduced into the inlet 4 is a low temperature state, that is, a temperature of -60 to -100 ℃ using a separate cooling means (for example, cooling means such as a heat exchanger) It can be in range.

Then, the hydrogen gas containing impurities introduced into the inlet 4 passes through the opened first injection valve 12, the second injection valve 14, and / or the third injection valve 16, respectively. The first filling tower 6, the second filling tower 8, and / or the third filling tower 10 are sequentially connected to the injection valves 12, 14, and 16.

At this time, the filling tower (6, 8, 10) is provided with a separate cooling means (not shown) may maintain the temperature inside each of the filling tower (6, 8, 10) to -60 to -100 ℃.

Then, impurities in the hydrogen gas introduced into each of the filling towers 6, 8, and 10 are adsorbed and removed by the adsorbent 2 in the form of molecular sieve at a low temperature of -60 to -100 ° C.

Next, the purified hydrogen gas passing through the filling towers 6, 8, and 10 is sequentially connected to the first filling tower 6, the second filling tower 8, and / or the third filling tower 10. It is discharged to the discharge port 24 through the installed first discharge valve 18, the second discharge valve 20 and / or the third discharge valve 22.

At this time, the purified hydrogen gas discharged to the outlet 24 may be reused in the semiconductor manufacturing process and / or solar cell manufacturing process, it may be collected separately.

On the other hand, all of the first filling tower 6, the second filling tower 8 and / or the third filling tower 10 may be used together to purify the hydrogen gas containing impurities, the first filling tower (6), the two filling towers (6, 8, 10) of the second filling tower (8) and the third filling tower (10) is operated at all times and in use at all times If the performance of the adsorbent 2 in the form of molecular sieve filled in one of the packed towers 6, 8, and 10 is substantially reduced and no further adsorption of impurities occurs, the packed tower 6, which is reduced in performance, Closing the injection valves 12, 14, 16 and discharge valves 18, 20, 22 connected to 8 and 10 stops the supply of hydrogen gas containing impurities flowing from the inlet port 4 and unused them. However, the injection valves 12, 14, 16 and the discharge valves 18, 20, 22 of the other filling towers 6, 8, and 10 may be opened to purify hydrogen gas containing impurities. .

In this case, the adsorbent 2 having substantially reduced performance may improve performance through a separate regeneration process. In this case, the temperature of the adsorbent 2 having substantially reduced performance may be 100 to 200 ° C. For example, the adsorbent 2 can be regenerated by increasing the temperature to 160 to 165 ° C. to remove the impurities adsorbed on the adsorbent 2.

At this time, the regeneration time for regenerating the adsorbent 2 is preferably 3 to 24 hours, preferably 10 to 12 hours.

As described above, the method for purifying hydrogen gas according to the present invention is adsorption of hydrogen gas containing impurities consisting of a hydrocarbon-based material, boron, phosphorus, or a mixture thereof in the form of a molecular sieve adsorbent in a low temperature state of -60 to -100 ° C. Adsorption is removed by passing through the bed, which provides a method for continuously purifying hydrogen gas in high purity continuously.

Hereinafter, the present invention will be described in detail through examples. However, the following examples are only for illustrating the present invention in detail and are not intended to limit the scope of the present invention by these examples.

<Examples>

Zeolite 4-A, a zeolite-based molecular sieve, was filled in a packed column to be 75% of the total packed column volume.

Then, hydrogen gas containing various inorganic material impurities including boron and phosphorus cooled to about -60 ° C was injected into the inlet provided on one side of the packed column.

Here, the amount of hydrogen gas containing impurities injected into the inlet was 500 kg per hour.

Then, while the hydrogen gas containing the impurity is injected, the discharge port provided on one side of the filling tower is opened so that the purified hydrogen gas passing through the filling tower is discharged.

At this time, the outlet was adjusted to the opening degree so that the pressure inside the filling tower is 75kPa.

Next, in order to evaluate the purity of the hydrogen gas discharged through the outlet, the purity of the silicon produced by supplying hydrogen with monosilane to the silicon deposition reactor was evaluated.

At this time, the weight ratio of the purified hydrogen and monosilane was mixed so that 0.65 ~ 3.58 was supplied to the silicon deposition reactor.

The results are shown in Table 1.

Comparative Example

The same procedure as in Example was carried out, but hydrogen gas containing impurities not purified by the packed column was mixed with monosilane and supplied to a silicon deposition reactor.

The results are shown in Table 1.

As shown in Table 1, the hydrogen gas purified according to the embodiment was found to effectively reduce the content of boron and carbon as impurities therein.

As described above, those skilled in the art will understand that the present invention can be implemented in other specific forms without changing the technical spirit or essential features. Therefore, it should be understood that the embodiments described above are all illustrative and not restrictive. The scope of the present invention should be construed as being included in the scope of the present invention all changes or modifications derived from the meaning and scope of the claims to be described later rather than the detailed description and equivalent concepts thereof.

1 is a block diagram of a hydrogen gas purification apparatus according to the present invention.

Description of the main parts of the drawing

2: adsorbent 4: inlet

6: first filling tower 8: second filling tower

10: third filling tower 12: first injection valve

14 second injection valve 16 third injection valve

18: first discharge valve 20: second discharge valve

22: third discharge valve 24: discharge port

Claims (13)

Hydrogen gas containing hydrogen gas containing an impurity consisting of a hydrocarbon-based material, boron, phosphorus or a mixture thereof through a adsorption layer filled with an adsorbent in the form of a molecular sieve at a low temperature of -60 to -100 ° C. A hydrogen gas purification method for removing impurities from gas. The method of claim 1, wherein the molecular sieve comprises a carbon molecular sieve, a zeolite-based molecular sieve, a silica-based molecular sieve, or an alumina molecular sieve. The method of claim 2, wherein the zeolite-based molecular sieve is hydrogen gas purification method characterized in that the zeolite 4-A having a specific surface area of 300 to 1,000 m ² / g. The method of claim 1, wherein the internal pressure of the hydrogen gas passing through the adsorption layer is 2 to 110 kPa. 2. The method of claim 1, wherein the hydrogen purification capacity of the purification method is processed in a continuous process manner at 500 kg or more per hour. The method of claim 1, If at least two adsorption layers are provided so that the performance of the adsorbent filled in one adsorption layer is substantially reduced, only one other adsorption layer is used, and regenerating the adsorbent filled in the adsorption layer substantially reduced in performance is recommended. Hydrogen gas purification method comprising. 7. The method of claim 6, wherein regenerating the adsorbent comprises heating the adsorbent to a temperature of 100 to 200 &lt; RTI ID = 0.0 &gt; 8. The method of claim 7, wherein the regeneration time is 3 to 24 hours. An inlet port through which hydrogen gas containing an impurity consisting of a hydrocarbon-based material, boron, phosphorus or a mixture thereof is introduced; At least two filling towers connected to the inlet to maintain a low temperature of -60 to -100 ° C. to adsorb and remove impurities contained in hydrogen gas, and filled with an adsorbent in the form of a molecular sieve; A discharge port connected to one side of the filling tower and passing through the filling tower to discharge purified hydrogen gas; An injection valve connected between the at least two filling towers and the inlet, respectively, to open and close an inflow path of hydrogen gas including impurities introduced into the respective filling towers; And And a discharge valve configured to be connected between the at least two filling towers and the discharge port, respectively, to discharge impurities from the hydrogen gas, passing through the respective filling towers and opening and closing the discharge path of the purified hydrogen gas. 10. The hydrogen gas purifying apparatus according to claim 9, further comprising cooling means for cooling hydrogen gas containing impurities introduced into the inlet at the front end of the inlet. 10. The hydrogen gas purifier of claim 9, wherein the adsorbent is a zeolite-based molecular sieve. 12. The hydrogen gas purifier of claim 11, wherein the zeolite-based molecular sieve is zeolite 4-A having a specific surface area of 300 to 1,000 m ² / g. 10. The hydrogen gas purifier of claim 9, wherein an internal pressure of the packed column is 2 to 110 kPa.

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