JP5242233B2 - Membrane separation type hydrogen production apparatus and hydrogen production method using the same - Google Patents

Description

  The present invention relates to a membrane separation type hydrogen production apparatus and a hydrogen production method using the same, and more particularly to a hydrogen production apparatus and a hydrogen production method capable of efficiently producing hydrogen using a hydrogen separation membrane. .

  Conventionally, in a membrane separation type hydrogen production apparatus that generates a reformed gas containing hydrogen by a hydrocarbon reforming reaction and separates hydrogen from the reformed gas using a Pd-based hydrogen separation membrane, In many cases, the reforming reaction is performed in a high-temperature region where the temperature increases. In contrast, among the Pd-based hydrogen separation membranes, the Pd-Ag alloy-based hydrogen separation membrane, which is particularly used, has higher hydrogen permeation characteristics as the membrane temperature increases, but the strength of the hydrogen separation membrane itself is high. descend. On the other hand, the Pd—Cu alloy-based hydrogen separation membrane exhibits the highest hydrogen permeation characteristics when the membrane temperature is around 450 ° C., and the hydrogen permeation characteristics and the strength of the hydrogen separation membrane itself decrease at higher temperatures.

  Conventionally, a hydrogen production apparatus using a hydrogen separation membrane has a reforming catalyst arranged around the hydrogen separation membrane as described in, for example, Patent Document 1 (Japanese Patent Laid-Open No. 06-048701). Was composed. However, in such a configuration, since the reforming catalyst layer and the hydrogen separation membrane are operated at substantially the same temperature, when the Pd-Ag hydrogen separation membrane is incorporated, the higher the reforming reaction temperature, the more hydrogen A reformed gas having a high concentration is obtained, and the hydrogen permeation rate of the hydrogen separation membrane is a desirable apparatus operating condition. However, there is a problem in terms of the strength of the hydrogen separation membrane at high temperatures such as 500 to 800 ° C. Arise. On the other hand, Pd-Cu-based hydrogen separation membranes, which can be expected to have higher strength than Pd-Ag-based hydrogen separation membranes, are desirable for the reforming reaction in the temperature range (350 to 600 ° C.) where the hydrogen permeation characteristics are maximized. It is lower than the temperature range (600 to 800 ° C.). Therefore, when a Pd—Cu-based hydrogen separation membrane is used and the hydrogen production apparatus is operated under a temperature condition where the Pd—Cu-based hydrogen separation membrane exhibits good hydrogen permeation performance, a reforming catalyst is disposed around the hydrogen separation membrane. In the same reactor, the reforming reaction is performed under a temperature condition lower than the optimum temperature range for the reforming reaction. Therefore, a reformed gas having a sufficiently high hydrogen concentration cannot be obtained in the reforming reaction. It has been difficult to supply a gas having a sufficiently high hydrogen concentration to the surface of the hydrogen separation membrane.

  Further, in the membrane separation type hydrogen production apparatus as described above, the temperature of the steam reforming catalyst decreases due to the endotherm associated with the reaction near the inlet of the raw material gas. On the other hand, the flow of gas in the reforming catalyst layer and the flow of gas on the low pressure side of the hydrogen separation membrane are counter-flowed for the purpose of reducing the reaction amount in the catalyst layer inlet region and suppressing coking due to the temperature drop. In addition, a steam reforming reactor has been proposed in which a heat transfer portion, which is a raw pipe portion having no hydrogen separation membrane, is provided at the catalyst layer inlet portion of the hydrogen separation pipe (Patent Document 2). However, this steam reforming reactor is intended to suppress the temperature drop in the reforming catalyst layer inlet region, and the hydrogen separation membrane is built in the reforming catalyst layer, and the hydrogen separation membrane is the reforming catalyst. Exposed to the same temperature as the layer.

  Further, in a reforming system that converts a fuel of a compound containing carbon and hydrogen into a fuel gas containing hydrogen in the reforming reactor, there is a reforming system in which no hydrogen separation membrane is provided in a region near the compound inlet of the reactor. It has been proposed (Patent Document 3). However, since this system stores hydrogen in the storage means using the differential pressure of hydrogen, the hydrogen partial pressure is increased by not providing a hydrogen separation membrane in the area near the inlet, and hydrogen is separated and stored by the hydrogen separation membrane. Since the hydrogen separation membrane is provided in contact with the reforming catalyst, the temperature of the hydrogen separation membrane is the same as the temperature of the reforming catalyst layer.

Japanese Patent Laid-Open No. 6-48701 Japanese Patent Laid-Open No. 6-40702 JP 2004-18280 A

  By the way, the conventional membrane separation type hydrogen production apparatus is preferably operated at a temperature of the hydrogen separation membrane of 350 to 550 ° C. from the viewpoint of durability and hydrogen permeation performance of the hydrogen separation membrane. In addition, the inside of the apparatus is also in a pressurized state, and because of the characteristics of the reforming reaction, which is an equilibrium reaction, it is operated under conditions where the hydrogen concentration in the reformed gas does not increase, so a high hydrogen permeation amount cannot be obtained. There was a problem. Further, when a pre-reformer is provided in order to increase the hydrogen concentration in the reformed gas, there arises a problem that a compact hydrogen production apparatus cannot be obtained.

  Accordingly, an object of the present invention is to perform a reforming reaction under conditions that provide a reformed gas with a high hydrogen concentration, and to separate and purify hydrogen using a hydrogen separation membrane under conditions suitable for the hydrogen separation membrane in the same reactor. An object of the present invention is to provide a hydrogen production apparatus that can be performed and, as a result, can produce hydrogen in a compact and high yield, and a hydrogen production method using the hydrogen production apparatus.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have supplied a mixed gas of hydrocarbon and steam to a steam reforming catalyst layer disposed in the upstream portion of the reactor, and improved steam reforming at a high temperature. The hydrogen separation membrane is supplied to the non-catalyst layer arranged in the downstream part of the steam reforming catalyst layer and cooled, and the hydrogen separation membrane is controlled to a temperature preferable for hydrogen permeation, so that the hydrogen concentration is high. Hydrogen is separated from the reformed gas by a hydrogen separation membrane, and further, a shift catalyst layer is disposed downstream of the non-catalyst layer, and hydrogen is separated into the shift catalyst layer and a reformed gas having a reduced hydrogen partial pressure is supplied. In addition, the inventors have found that hydrogen can be efficiently produced by generating hydrogen by a shift reaction and separating the generated hydrogen by a hydrogen separation membrane, thereby completing the present invention. That is, the present invention includes the following inventions.

(1) A membrane separation type hydrogen production apparatus comprising a steam reforming catalyst layer comprising a steam reforming catalyst for steam reforming hydrocarbons, and a hydrogen separation membrane having hydrogen permeability,
The steam reforming catalyst layer is disposed upstream of the hydrocarbon and steam inlet, the non-catalytic layer comprising non-catalytic particles is disposed downstream of the steam reforming catalyst layer, and the non-catalyst A shift catalyst layer composed of a shift catalyst that performs a shift reaction of the reformed gas is disposed downstream of the layer,
The hydrogen separation membrane is disposed so as to penetrate at least a part of the non-catalyst layer without penetrating the shift catalyst layer and being disposed on or in contact with the steam reforming catalyst layer. apparatus.

(2) The membrane-separated hydrogen production apparatus according to (1), wherein the non-catalytic particles are at least one of alumina, silica, and silica-alumina.

(3) The above-mentioned hydrogen separation membrane is obtained by providing a barrier layer on a sintered filter portion of a metal tube having a sintered filter portion, and placing a palladium-copper alloy plating film on the barrier layer ( The membrane separation type hydrogen production apparatus of 1) or (2).

(4) A mixed gas of hydrocarbon and steam is supplied to the steam reforming catalyst layer of the membrane separation type hydrogen production apparatus according to any one of (1) to (3) above, and hydrogen is mainly contained by the steam reforming reaction. To generate reformed gas,
Next, after the reformed gas is supplied to the non-catalyst layer and brought into contact with the non-catalyst particles to lower the temperature of the reformed gas,
Hydrogen is selectively permeated through the hydrogen separation membrane to extract hydrogen,
Furthermore, a reformed gas from which hydrogen has been separated is supplied to the shift catalyst layer, hydrogen is generated by a shift reaction, and hydrogen is selectively permeated through the hydrogen separation membrane to extract hydrogen.

(5) The method for producing hydrogen according to (4), wherein the temperature of the steam reforming catalyst layer is higher than the temperature of the hydrogen separation membrane.

(6) The method for producing hydrogen according to (5) above, wherein the temperature of the steam reforming catalyst layer is 600 to 800 ° C., and the temperature of the hydrogen separation membrane is less than 600 ° C.

(7) The method for producing hydrogen according to any one of (4) to (6), wherein the hydrocarbon is at least one selected from the group consisting of a naphtha fraction, a gasoline fraction, a kerosene fraction, and a light oil fraction.

  According to the present invention, since the reforming reaction and the hydrogen separation and purification using the hydrogen separation membrane can be performed under suitable temperature conditions, respectively, a compact membrane separation type hydrogen production apparatus capable of recovering hydrogen with high efficiency and the A highly efficient hydrogen production method using the apparatus can be provided.

  Below, the membrane separation type | mold hydrogen production apparatus and hydrogen production method of this invention are demonstrated in detail using FIG. FIG. 1 is a schematic view showing an example of a membrane separation type hydrogen production apparatus of the present invention. In the membrane-separated hydrogen production apparatus shown in FIG. 1, a steam reforming catalyst layer 2 is disposed upstream from the hydrocarbon and steam inlet 1, and a non-stream is formed downstream from the steam reforming catalyst layer 2. A non-catalyst layer 3 made of catalyst particles is arranged, a shift catalyst layer 4 made of a shift catalyst that performs a shift reaction of the reformed gas is arranged downstream of the non-catalyst layer 3, and further, a hydrogen separation membrane 5 The non-catalyst layer 3 is arranged so as to be at least partially covered without passing through or in contact with the steam reforming catalyst layer 2 through the shift catalyst layer 4. Further, the membrane separation type hydrogen production apparatus shown in FIG. 1 is provided with a non-permeate gas outlet 6 on the downstream side of the shift catalyst layer 4 and further has a product hydrogen outlet 7 connected to the hydrogen separation membrane 5. Prepare.

  In the membrane separation type hydrogen production apparatus shown in FIG. 1, hydrocarbons and steam are supplied to the steam reforming catalyst layer 2 through the inlet 1 to generate a reformed gas by a steam reforming reaction. The generated reformed gas is supplied to the non-catalyst layer 3, cooled, permeates the hydrogen separation membrane 5 partially incorporated in the non-catalyst layer 3, and is taken out of the apparatus through the outlet portion 7 as product hydrogen. . The reformed gas that has not permeated the hydrogen separation membrane 5 is supplied to the shift catalyst layer 4 and undergoes a shift reaction. Hydrogen generated by the shift reaction passes through the hydrogen separation membrane 5 in contact with the shift catalyst layer 4. The permeated product hydrogen is taken out from the apparatus through the outlet 7 as product hydrogen. On the other hand, the gas that has passed through the shift catalyst layer 4 without passing through the hydrogen separation membrane 5 is discharged out of the apparatus from the outlet 6 as a non-permeating gas.

[Raw material hydrocarbon]
As the hydrocarbon used as a raw material for producing hydrogen by the reforming reaction, a hydrocarbon having a boiling point of 370 ° C. or lower and a mixture thereof can be used. For example, methane, ethane, propane, butane, pentane, natural gas, LP gas and other hydrocarbons in the gaseous state at room temperature, as well as naphtha fraction, gasoline fraction, kerosene fraction, light oil fraction, etc. The following petroleum-based hydrocarbons can be used.

  A naphtha fraction is a fraction having a boiling point within a range of 30 ° C. to 180 ° C. as a boiling point range among fractions obtained by distillation separation of crude oil, natural gas condensate, and the like. Examples of the naphtha fraction include a light naphtha fraction having a boiling range of about 30 to 80 ° C, a heavy naphtha fraction having a boiling range of about 80 to 180 ° C, and a whole naphtha fraction having a boiling range of about 30 to 180 ° C. Etc. are included.

  The gasoline fraction is a fraction having a boiling point in the range of 30 ° C. to 200 ° C. as a boiling range, and the boiling point used for the preparation of automobile gasoline is within the above range in addition to commercial automobile gasoline and industrial gasoline. An intermediate product (also called a base material), an intermediate product having a boiling point in the above range, and a fraction corresponding to automobile gasoline are also included.

  A kerosene fraction is a fraction having a boiling point within a range of 140 ° C. to 270 ° C. as a boiling point among fractions obtained by distillation separation of crude oil, natural gas condensate, and the like. In addition to commercial kerosene such as for use, a fraction corresponding to kerosene having a boiling point within the above range is included.

  The light oil fraction is a fraction having a boiling point in the boiling range of 160 ° C. to 370 ° C. In addition to the commercially available light oil used for diesel engines, the fraction corresponding to the light oil having the boiling point in the above range is included. included.

  Liquid hydrocarbons such as gaseous hydrocarbons such as methane and LPG, naphtha fractions, gasoline fractions, kerosene fractions, and diesel oil fractions are preferred from the viewpoint of product distribution, cost, and availability. Minutes are preferred. Further, these hydrocarbons preferably have a low sulfur content, particularly those having a sulfur content of 50 mass ppb or less, from the viewpoint of poisoning the steam reforming catalyst.

[Steam reforming catalyst, steam reforming catalyst layer]
As the steam reforming catalyst used in the present invention, a normal steam reforming catalyst can be used. For example, at least one catalytically active component selected from Fe, Co, Ni, Ru, Rh, Pd, Ir, and Pt is used as an oxide of Mg, Al, Si, Ti, Zr, Ba, La and / or Those supported on a carrier containing at least one carrier component selected from hydrated oxides can be used. From the viewpoint of suppressing the occurrence of coking, it is preferable to use Ru or Rh as the catalyst active component.

  These steam reforming catalysts are arranged on the most upstream side with respect to the supply direction of the mixed gas of hydrocarbon and steam as a steam reforming catalyst layer 2, and the steam reforming catalyst layer 2 is a modification of the hydrogen production apparatus. Corresponds to the mass part R. The amount of the steam reforming catalyst to be included in the steam reforming catalyst layer 2 can be appropriately determined depending on the type of hydrocarbon as a raw material, the reforming reaction temperature, the steam / carbon ratio, and the like.

[Non-catalytic particles, non-catalytic layer]
In the present invention, non-catalytic particles refer to particles that have substantially no catalytic action on the reforming reaction, and serve to cool the reformed gas. Non-catalytic particles used for cooling the reformed gas include ceramic balls such as magnesia, magnesia-calcium oxide-silica, magnesia-silica, alumina, silica, silica-alumina, etc., which have low reaction activity with respect to the reformed gas. Among these, alumina, silica, and silica-alumina are preferable. Examples of the shape include various shapes such as a ring shape, a spherical shape, and a pellet shape.

  The non-catalyst particles are arranged downstream of the steam reforming catalyst layer 2 to form the non-catalyst layer 3. In the non-catalyst layer 3, a hydrogen separation membrane 5 to be described later is disposed so as to cover at least a part thereof, but the steam reforming catalyst layer 2 and the hydrogen separation membrane 5 are appropriately separated via the non-catalyst layer 3. Thus, the reformed gas is cooled by passing through the non-catalyst layer 3 so that the hydrogen separation membrane 5 has a temperature preferable for hydrogen permeation performance. That is, the non-catalytic layer 3 from the steam reforming catalyst layer 2 to the hydrogen separation membrane 5 corresponds to the cooling unit C, and the portion of the non-catalytic layer 3 in which the hydrogen separation membrane 5 is disposed corresponds to the upper separation unit U. A portion of the shift catalyst layer 4 described later corresponds to the lower separation portion L. It is also possible to forcibly cool from the outside of the reactor with a cooling pipe or the like. Further, a cooling pipe in which a heat medium or the like is circulated in the non-catalyst layer 3 may be directly passed. In this manner, in the cooling section C, the reformed gas is cooled to a temperature suitable for the hydrogen permeability of the hydrogen separation membrane 5, that is, 350 ° C. or higher and lower than 600 ° C., preferably 350 to 550 ° C.

[Shift catalyst, shift catalyst layer]
Further, a shift catalyst layer 4 including a shift catalyst is disposed downstream of the non-catalyst layer 3. In the non-catalyst layer 3, hydrogen is separated by the hydrogen separation membrane 5 and the reformed gas having a reduced hydrogen partial pressure is supplied to the shift catalyst layer 4, whereby hydrogen is further generated by the shift reaction. By separating, hydrogen can be produced with higher efficiency. The temperature of the shift catalyst layer is preferably 350 ° C. or higher and lower than 600 ° C., more preferably 350 to 550 ° C.

A conventionally well-known thing can be used as a shift catalyst used for this invention. For example, examples of the catalytically active component include those of noble metals such as Fe ₂ O ₃ , Cu—ZnO, Ru, Pt, and Au. What carried these catalyst active components in magnesia, magnesia-calcium oxide-silica, magnesia-silica, alumina, silica-alumina, silica, etc. can be used as a shift catalyst. The amount of the shift catalyst included in the shift catalyst layer 4 can be appropriately determined depending on the type of raw material hydrocarbon used, the shift reaction temperature, and the like.

[Hydrogen separation membrane]
The hydrogen separation membrane 5 used in the present invention is not particularly limited as long as it is a material having selective hydrogen permeability, but is preferably a palladium membrane or palladium alloy membrane having high hydrogen permeability, and palladium-copper, palladium- A palladium alloy film of silver or the like is more preferable.

  As the hydrogen separation membrane 5, as shown in FIG. 2, a barrier layer 10 is provided on a sintered filter portion 8 of a metal tube 9 having a sintered filter portion 8, and a palladium alloy plating is formed on the barrier layer 10. It is preferable to use a hydrogen separation membrane provided with a membrane 11. Here, the sintered filter portion 8 and the metal tube 9 are preferably made of stainless steel, and the barrier layer 10 is preferably made of zirconia, alumina, or the like, and the palladium alloy plating film 11 includes a palladium-copper alloy. And a palladium-silver alloy plating film are preferred, and a palladium-copper alloy plating film is particularly preferred. The barrier layer 10 prevents the metal component of the sintered filter portion 8 from diffusing into the palladium alloy plating film 11 to deteriorate the hydrogen permeability of the plating film 11, and increases the smoothness of the surface to increase the surface smoothness. It has the effect of preventing defects in the palladium alloy plating film 11.

  The hydrogen separation membrane 5 penetrates the shift catalyst layer 4 and is disposed so as to be at least partially covered with the non-catalyst layer 3 without being disposed or in contact with the steam reforming catalyst layer 2.

[Hydrogen production method]
The hydrogen production method using the membrane separation type hydrogen production apparatus of the present invention is performed as follows. First, the mixed gas of hydrocarbon and steam is supplied to the steam reforming catalyst layer 2 to perform a steam reforming reaction to generate a reformed gas mainly composed of hydrogen. Here, the ratio of hydrocarbon to water vapor is preferably in the range of 2.5 to 4.0 as the steam / carbon ratio (S / C ratio), and more preferably in the range of 2.8 to 3.5. When the S / C ratio is low, coking occurs and the activity of the steam reforming catalyst is reduced. Further, when the S / C ratio is higher than necessary, the efficiency is lowered.

The temperature of the steam reforming catalyst layer 2, that is, the temperature of the reforming reaction is preferably 600 to 800 ° C, more preferably 650 to 750 ° C. When the temperature of the reforming reaction is less than 600 ° C., the hydrogen fraction is 30 vol% or less (under the condition of a reaction pressure of 0.9 MPaG with a methane raw material) and a sufficient hydrogen permeation amount cannot be obtained. If it exceeds, a heat-resistant material (such as Kanthal (registered trademark) , Inconel (registered trademark) , Hastelloy (registered trademark) ) is required as the material of the reaction tube and the cost becomes high.

  The pressure for the reforming reaction is preferably 0.5 to 1.5 MPaG, more preferably 0.7 to 1.2 MPaG. When the reaction pressure is too low, a sufficient amount of hydrogen permeation cannot be obtained, and when the reaction pressure is too high, the hydrocarbon reaction (reaction toward the hydrogen generation side) is difficult to proceed.

When kerosene is used as the raw material hydrocarbon, SV (kerosene-based LHSV) is preferably in the range of 0.3 to 3.0 h ^{−1 in} the current catalyst, and in the range of 0.3 to 1.7 h ⁻¹ . More preferred.

  Next, the reformed gas is supplied to the non-catalyst layer 3 disposed on the downstream side of the steam reforming catalyst layer 2 and brought into contact with the non-catalyst particles so that the temperature of the reformed gas is lower than that of the steam reforming catalyst layer 2 and hydrogen. After cooling to a temperature preferable for hydrogen separation by the separation membrane 5, particularly below 600 ° C., hydrogen is permeated and separated by the hydrogen separation membrane 5. In the present invention, the reforming reaction is performed in the steam reforming catalyst layer 2 under a temperature condition preferable for the steam reforming reaction, so that the reformed gas has a high hydrogen content. Hydrogen can be separated.

  Further, the reformed gas from which hydrogen has been separated by the hydrogen separation membrane 5 is supplied to the shift catalyst layer 4 disposed on the downstream side of the non-catalyst layer 3 to generate more hydrogen by the shift reaction, and the shift catalyst layer 4 The generated hydrogen is separated by the hydrogen separation membrane 5 disposed so as to pass through. Since hydrogen is separated by the non-catalyst layer 3 and the hydrogen partial pressure is reduced, hydrogen is produced by the shift reaction, so that the amount of hydrogen produced can be increased and hydrogen can be produced with high efficiency.

[Modified Embodiment]
In the above, the present invention has been described with reference to FIG. 1, but the membrane separation type hydrogen production apparatus of the present invention may have a structure other than that shown in FIG. For example, as shown in FIG. 3, it is also possible to provide a cooling pipe 12 in the cooling part C and to have a structure for forcibly cooling by flowing a cooling gas, for example. At this time, by using the raw material gas as the cooling gas and using the heat of the reformed gas for preheating the raw material gas, the thermal efficiency can be improved. Further, instead of providing the cooling pipe 12 in the cooling section C, as shown in FIGS. 4 and 5, the cooling section C is formed as a multi-tube heat exchanger type, and the non-catalytic layer 3 is filled in the pipe 13, You may make it cool the outer side of 13 with a cooling gas. Moreover, the membrane separation type hydrogen production apparatus of the present invention can also include a plurality of hydrogen separation membranes 5 as shown in FIG.

  According to the present invention, since the reforming reaction is performed in the steam reforming catalyst layer 2 at a high temperature (600 to 800 ° C.), a reformed gas having a high hydrogen concentration can be obtained. The reformed gas is then cooled to a temperature at which the separation performance of the hydrogen separation membrane 5 is sufficiently exerted by the non-catalytic layer 3, and hydrogen is separated at a high permeability in the separation section where the hydrogen separation membrane 5 is installed. The Further, the reformed gas whose hydrogen concentration has been lowered by the hydrogen separation membrane 5 is then introduced into the shift catalyst layer 4 filled with the shift catalyst, undergoes a shift reaction, generates more hydrogen, and is generated by the shift reaction. Hydrogen is recovered by the hydrogen separation membrane 5.

  As described above, according to the present invention, it is possible to provide a membrane separation type hydrogen production apparatus and a hydrogen production method capable of recovering hydrogen with high efficiency. The membrane-separated hydrogen production apparatus of the present invention can produce high-purity hydrogen gas in a compact configuration with high efficiency and a high recovery amount. Therefore, a hydrogen production apparatus for a polymer electrolyte fuel cell (PEFC), or It can be suitably used as an on-site type hydrogen production apparatus used in a hydrogen station.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the following examples.

Example 1
A SUS 9.525 mm ( 3/8 inch ) tube having a 45 mm-long hydrogen permeation section in a SUS reaction tube having an inner diameter of 43 mmφ and a length of 700 mm having the structure shown in FIG. 1 is a hydrogen separation membrane module. The apparatus provided as was used. The upper part of the reaction tube was filled with a general steam reforming catalyst (Ru system, size 2 mmφ) so as to have a layer height of 30 mm, thereby forming a steam reforming catalyst layer.

Using raw material hydrocarbon (methane), reaction temperature of steam reforming catalyst layer 600 ° C. (lower end of steam reforming catalyst layer), reaction pressure 0.9 MPaG, steam / carbon ratio (S / C) = 3.0, The reforming reaction was performed under the condition of GHSV (methane + steam) = 1500 h ⁻¹ (the catalyst layer is based on the volume of the reforming catalyst layer).

  The cooling part was filled with non-catalytic particles of silica-alumina ceramic balls (2 mmφ) having no reaction activity with respect to hydrocarbons and water vapor, and a distance was taken until the reaction product gas was cooled to 500 ° C.

  In the upper hydrogen separation section, the silica-alumina ceramic balls are filled around the hydrogen separation membrane in the same manner as the cooling section, and the reformed gas generated in the reforming section is introduced into the hydrogen separation section with its composition. Hydrogen separation was performed. Here, as a hydrogen separation membrane module, Pd—Cu (Cu) is provided on a support in which a stabilized zirconia layer (about 20 μm) is disposed as a barrier layer on a sintered filter portion of a SUS tube having a sintered filter portion made of SUS. Is a module having a plating film (film thickness of about 3 μm).

  In the lower hydrogen separation part, the same catalyst as the reforming catalyst is filled around the hydrogen separation membrane as a catalyst for promoting the shift reaction, with a layer height of 20 mm above the lower end of the hydrogen separation membrane, and the hydrogen separated by the upper hydrogen separation part. Hydrogen was separated while producing hydrogen by shift reaction of the reformed gas having a reduced concentration.

  As a result, 0.24 L / min of hydrogen was obtained as the hydrogen permeated through the hydrogen separation membrane, and the hydrogen recovery rate (permeated hydrogen amount / produced hydrogen amount) was 59.8%.

(Comparative Example 1)
As shown in FIG. 7, only the same steam reforming catalyst as used in Example 1 is filled in the apparatus having the same structure as in Example 1 30 mm above and around the hydrogen separation membrane. The experiment was performed under the same conditions as in Example 1 except that the temperature at the lower end of the steam reforming catalyst layer was 500 ° C. As a result, 0.16 L / min of hydrogen was obtained as hydrogen permeated through the hydrogen separation membrane, and the hydrogen recovery rate was 46.8%, which was about 2/3 of the hydrogen recovery amount compared to Example 1. .

It is a schematic diagram which shows an example of the membrane separation type | mold hydrogen production apparatus of this invention. It is a fragmentary sectional view of the suitable example of the hydrogen separation membrane used for the membrane separation type | mold hydrogen production apparatus of this invention. It is a schematic diagram which shows another example of the membrane separation type | mold hydrogen production apparatus of this invention. It is a schematic diagram which shows another example of the membrane separation type | mold hydrogen production apparatus of this invention. It is sectional drawing which follows the VV line of FIG. It is a schematic diagram which shows another example of the membrane separation type | mold hydrogen production apparatus of this invention. It is a schematic diagram which shows an example of the membrane separation type | mold hydrogen production apparatus used by the comparative example 1. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Entrance part of hydrocarbon and steam 2 Steam reforming catalyst layer 3 Non-catalyst layer 4 Shift catalyst layer 5 Hydrogen separation membrane 6 Non-permeate gas exit part 7 Product hydrogen exit part 8 Sintering filter part 9 Metal tube 10 Barrier layer 11 Plating film of palladium alloy 12 Cooling pipe 13 Pipe R Reforming part C Cooling part U Upper separation part L Lower separation part

Claims (7)

A membrane separation type hydrogen production apparatus comprising a steam reforming catalyst layer comprising a steam reforming catalyst for steam reforming hydrocarbons, and a hydrogen separation membrane having hydrogen permeability,
The steam reforming catalyst layer is disposed upstream of the hydrocarbon and steam inlet, the non-catalytic layer comprising non-catalytic particles is disposed downstream of the steam reforming catalyst layer, and the non-catalyst A shift catalyst layer composed of a shift catalyst that performs a shift reaction of the reformed gas is disposed downstream of the layer,
The hydrogen separation membrane passes through the shift catalyst layer and is disposed so as to be at least partially in the non-catalyst layer without being disposed or in contact with the steam reforming catalyst layer. Membrane separation type hydrogen production equipment.   The membrane-separated hydrogen production apparatus according to claim 1, wherein the non-catalytic particles are at least one of alumina, silica, and silica-alumina.   The hydrogen separation membrane is characterized in that a barrier layer is provided on a sintered filter portion of a metal tube having a sintered filter portion, and a palladium-copper alloy plating film is disposed on the barrier layer. The membrane-separated hydrogen production apparatus according to claim 1 or 2. A reformed gas mainly comprising hydrogen by a steam reforming reaction by supplying a mixed gas of hydrocarbon and steam to the steam reforming catalyst layer of the membrane separation type hydrogen production apparatus according to any one of claims 1 to 3. To generate
Next, after the reformed gas is supplied to the non-catalyst layer and brought into contact with the non-catalyst particles to lower the temperature of the reformed gas,
Hydrogen is selectively permeated through the hydrogen separation membrane to extract hydrogen,
Further, the reformed gas from which hydrogen has been separated is supplied to the shift catalyst layer, hydrogen is generated by a shift reaction, and hydrogen is selectively permeated through the hydrogen separation membrane to extract hydrogen. Method.   The method for producing hydrogen according to claim 4, wherein the temperature of the steam reforming catalyst layer is higher than the temperature of the hydrogen separation membrane.   The temperature of the said steam reforming catalyst layer is 600-800 degreeC, The temperature of the said hydrogen separation membrane is less than 600 degreeC, The hydrogen manufacturing method of Claim 5.   The method for producing hydrogen according to any one of claims 4 to 6, wherein the hydrocarbon is at least one selected from the group consisting of a naphtha fraction, a gasoline fraction, a kerosene fraction, and a light oil fraction.

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