JP2005146054A - Desulfurizing agent and desulfurizing method using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an industrially advantageous desulfurizing agent which can efficiently remove sulfur compounds in a hydrocarbon raw material and/or an oxygen-containing hydrocarbon raw material to a very low concentration and has a long life, and a method for manufacturing hydrogen for fuel cells by subjecting fuels subjected to a desulfurization treatment using the desulfurizing agent to steam reforming, partial oxidation reforming or auto-thermal reforming. <P>SOLUTION: The desulfurizing agent for removing sulfur compounds in the hydrocarbon raw material and/or the oxygen-containing hydrocarbon raw material comprises a carrier and a metal component supported thereon. At least 80 mol% of the metal component are in the metallic state and have a metal crystallite diameter of at most 4.0 nm. The manufacturing method of hydrogen for fuel cells comprises desulfurizing a fuel using the desulfurizing agent and subsequently reforming the fuel. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a desulfurization agent, a desulfurization method using the same, and a method for producing hydrogen for fuel cells. Specifically, a desulfurization agent that can efficiently remove sulfur content in a hydrocarbon raw material and / or oxygen-containing hydrocarbon raw material to an extremely low concentration and has a long life, and a fuel desulfurized using the desulfurization agent The present invention relates to a method for producing hydrogen for fuel cells.

  In recent years, new energy technology has attracted attention due to environmental problems, and fuel cells are attracting attention as one of the new energy technologies. This fuel cell converts chemical energy into electrical energy by electrochemically reacting hydrogen and oxygen, and has a feature of high energy use efficiency. Alternatively, research into practical use is actively conducted for automobiles and the like. For this fuel cell, types such as a phosphoric acid type, a molten carbonate type, a solid oxide type, and a solid polymer type are known depending on the type of electrolyte used. On the other hand, as a hydrogen source, liquefied natural gas mainly composed of methanol and methane, city gas mainly composed of this natural gas, synthetic liquid fuel using natural gas as a raw material, and carbonization of petroleum naphtha and kerosene, etc. The use of hydrogen oil has been studied.

When the fuel cell is used for consumer use or automobile use, the hydrocarbon oil is liquid at room temperature and normal pressure, and is easy to store and handle. Since the supply system is maintained, it is advantageous as a hydrogen source. However, such hydrocarbon oil has a problem that the content of sulfur is higher than that of methanol or natural gas. When hydrogen is produced using this hydrocarbon oil, generally, a method of subjecting the hydrocarbon oil to steam reforming or partial oxidation reforming in the presence of a reforming catalyst is used. In such reforming treatment, the reforming catalyst is poisoned by the sulfur content in the hydrocarbon oil. Therefore, from the viewpoint of catalyst life, the hydrocarbon oil is subjected to desulfurization treatment to reduce the sulfur content. It is important to make the concentration as low as possible.
In addition, when hydrogen is directly mounted on an automobile, it has been studied to add an odorant to hydrogen from the viewpoint of safety, and it is also possible to reduce the concentration of an odorant consisting of sulfur compounds present in feedstock as much as possible. It is important to.

As a desulfurization method for petroleum hydrocarbons, many studies have been made so far. For example, a hydrodesulfurization catalyst such as Co-Mo / alumina or Ni-Mo / alumina and a hydrogen sulfide adsorbent such as ZnO are usually used. A method of hydrodesulfurizing at a temperature of 200 to 400 ° C. under a pressure of 5 MPa · G is known. This method performs hydrodesulfurization under harsh conditions and removes sulfur by converting it to hydrogen sulfide. For small-scale distributed fuel cells, safety and environmental considerations, high-pressure gas control methods, etc. It is not preferable in relation to related laws and regulations. That is, for fuel cells, a desulfurization agent that can desulfurize fuel for a long time under a condition of less than 1 MPa · G is desired.
On the other hand, a nickel-based adsorbent has been proposed as a desulfurizing agent that adsorbs and removes sulfur in fuel oil under mild conditions (for example, see Patent Documents 1 to 12), and an improved nickel-copper system. Adsorbents have been proposed (see, for example, Patent Document 11 or 13).
However, the techniques disclosed in these documents are not at a practical level from the viewpoint of the life of the desulfurizing agent, are difficult to put into practical use, and further improvements have been desired.

Japanese Examined Patent Publication No. 6-65602 Japanese Patent Publication No.7-115842 Japanese Patent Laid-Open No. 1-188405 Japanese Patent Publication No.7-115843 JP-A-2-275701 JP-A-2-204301 Japanese Patent Laid-Open No. 5-70780 Japanese Patent Laid-Open No. 6-80972 JP-A-6-91173 JP-A-6-228570 JP 2001-279259 A JP 2001-342465 A JP-A-6-315628

  Under such circumstances, the present invention can efficiently remove the sulfur content in the hydrocarbon raw material and / or the oxygen-containing hydrocarbon raw material to a very low concentration and has a long life and is industrially advantageous. And a method for producing hydrogen for a fuel cell by subjecting a hydrocarbon raw material and / or oxygen-containing hydrocarbon raw material desulfurized using this desulfurizing agent to steam reforming, partial oxidation reforming or autothermal reforming treatment It is intended to do. Another object of the present invention is to provide a desulfurization agent applicable to desulfurization of hydrogen or city gas to which an odorant composed of a sulfur compound is added.

As a result of various researches to achieve the above object, the present inventors have obtained a desulfurization agent having a metal component supported on a carrier, the reduction degree of the metal component (the metal in the metal state in all metal components) The present inventors have found that a desulfurizing agent having a high component content) and a metal crystallite diameter of the metal of 4.0 nm or less can solve the above problems, and has completed the present invention.
That is, the present invention
(1) A desulfurization agent for removing a sulfur compound in a hydrocarbon raw material and / or an oxygen-containing hydrocarbon raw material obtained by supporting a metal component on a carrier, wherein 80 mol% or more of the metal component is in a metal state, And a desulfurizing agent having a metal crystallite diameter of 4.0 nm or less,
(2) The desulfurization agent according to the above (1), which contains nickel as a metal component, and the nickel content is in the range of 50 to 90% by mass as a conversion amount of NiO (nickel oxide) with respect to the total amount of the desulfurization agent. ,
(3) The desulfurization agent according to the above (1) or (2), which contains copper as a metal component, and the copper content is 40% by mass or less as a CuO (copper oxide) conversion amount with respect to the total amount of the desulfurization agent. ,
(4) The desulfurization agent according to any one of (1) to (3), wherein the support contains at least one selected from silica, alumina, and silica-alumina.
(5) The above (1) to (4), wherein the hydrocarbon raw material and / or the oxygen-containing hydrocarbon raw material is at least one selected from kerosene, light oil, liquefied petroleum gas (LPG), naphtha, gasoline, natural gas, and dimethyl ether. A desulfurizing agent according to any one of
(6) Desulfurization of the hydrocarbon raw material and / or the oxygen-containing hydrocarbon raw material at a temperature in the range of −40 to 300 ° C. using the desulfurizing agent according to any one of (1) to (5) above. Desulfurization method,
(7) For a fuel cell, wherein the hydrocarbon raw material and / or the oxygen-containing hydrocarbon raw material is desulfurized using the desulfurizing agent according to any one of (1) to (6) above, and then reformed. A method for producing hydrogen,
(8) The method for producing hydrogen for a fuel cell according to (7), wherein the reforming is steam reforming, partial oxidation reforming, or autothermal reforming,
(9) The method for producing hydrogen for fuel cells according to (7) or (8) above, wherein the catalyst used for reforming is a ruthenium catalyst or a nickel catalyst.
(10) The method for producing hydrogen for a fuel cell according to (9), wherein the carrier component of the catalyst used for reforming contains at least one selected from manganese oxide, cerium oxide, and zirconium oxide,
(11) A fuel cell system using hydrogen produced by the method according to any one of (7) to (10) above,
Is to provide.

  ADVANTAGE OF THE INVENTION According to this invention, the sulfur content in a hydrocarbon raw material and / or oxygen-containing hydrocarbon raw material can be efficiently removed to very low concentration, and the desulfurization agent with a long lifetime can be provided. By applying this desulfurization agent to the production of hydrogen for fuel cells, the catalyst for producing hydrogen from the hydrocarbon raw material and / or the oxygen-containing hydrocarbon raw material can function effectively, and the life of the reforming catalyst Can be extended.

The desulfurization agent of the present invention is a desulfurization agent for removing sulfur compounds in a hydrocarbon raw material and / or oxygen-containing hydrocarbon raw material obtained by supporting a metal component on a carrier, and 80 mol% or more of the metal component is a metal. The metal crystallite diameter is 4.0 nm or less.
In the desulfurization agent of this invention, it is essential that 80 mol% or more of a metal component is a metal state, ie, a reduction degree is 80% or more. If the ratio of the metal component in the metal state is less than 80 mol%, the number of active sites on the surface of the desulfurizing agent is small, and the desired desulfurization activity may not be obtained. From the viewpoint of desulfurization activity, the ratio of the metal component in the metal state is preferably 85 mol% or more, and more preferably 90 mol% or more.
Moreover, it is essential that the metal crystallite diameter is 4.0 nm or less. When the metal crystallite diameter is 4.0 nm or more, the number of active sites decreases, and sufficient desulfurization activity cannot be obtained. From the viewpoint of desulfurization activity, the metal crystallite diameter is preferably 3.5 nm or less.

Although it does not specifically limit as said metal component in the range with the effect of this invention, It is preferable to contain nickel. Examples of the nickel component include nickel oxide, metallic nickel obtained by reducing the nickel oxide, nickel carbonate, nickel nitrate, nickel chloride, nickel sulfate, nickel acetate and the like.
As content of nickel, it is preferable that it is the range of 50-90 mass% as NiO (nickel oxide) conversion amount based on the desulfurization agent whole quantity. When the nickel content is 50% by mass or more, a high desulfurization activity is obtained. When the nickel content is 90% by mass or less, the content of the carrier, which will be described in detail later, is ensured, so that the surface area of the desulfurizing agent becomes sufficient. Will not drop. From this viewpoint, the nickel content is preferably in the range of 60 to 90% by mass, and more preferably in the range of 65 to 85% by mass.

Moreover, it is preferable that the desulfurization agent of this invention contains copper as a metal component. The content of the copper component is preferably 40% by mass or less in terms of CuO (copper oxide) based on the total amount of the desulfurizing agent. When the copper content is 40% by mass or less, the function as a desulfurizing agent can be sufficiently exhibited without inhibiting the effect of the nickel. From the viewpoints described above and from the viewpoint of increasing the degree of reduction of the coexisting nickel, the copper content is more preferably in the range of 0.1 to 40% by mass, and particularly in the range of 0.1 to 30% by mass. It is preferable.
Furthermore, in the desulfurization agent of the present invention, the total amount of NiO and CuO is preferably in the range of 60 to 90% by mass based on the total amount of the desulfurization agent. When the total amount is within this range, the number of active points necessary for desulfurization is sufficient, the desired desulfurization performance is obtained, and the surface area of the desulfurization agent is reduced because the ratio of the carrier described in detail later is sufficient, There is no inconvenience that the desulfurization performance is lowered. From the above viewpoint, the total amount of NiO and CuO is preferably in the range of 70 to 90% by mass.

  Next, as the carrier used in the present invention, a porous inorganic oxide is particularly preferable, and specific examples include silica, alumina, silica-alumina, titania, zirconia, magnesia, zinc oxide, white clay, clay and diatomaceous earth. be able to. These may be used alone or in combination of two or more. Of these, silica, alumina, silica-alumina and mixtures thereof are particularly preferable. In the present invention, the metal component supported on these carriers preferably contains a nickel component and / or a copper component as described above, and further, if desired, a small amount of other metal components such as cobalt, iron, manganese, and chromium. You may mix.

Next, a manufacturing method in the case where a carrier is used and a metal component such as nickel is supported thereon will be described in detail below.
The method for supporting nickel, copper, and other metal components on the carrier is not particularly limited, and any known method such as an impregnation method, a coprecipitation method, or a kneading method can be employed. A desulfurization agent in which nickel-copper is supported on a silica-alumina support, which is one of the preferred desulfurization agents of the present invention, can be produced, for example, by a coprecipitation method as shown below. In this coprecipitation method, first, an acidic aqueous solution or acidic aqueous dispersion containing a nickel source, an aluminum source, and a copper source, and a basic aqueous solution containing a silicon source and an inorganic base are prepared. Examples of the nickel source used in the former acidic aqueous solution or acidic aqueous dispersion include nickel chloride, nickel nitrate, nickel sulfate, nickel acetate, nickel carbonate, and hydrates thereof. Examples of the copper source include copper chloride, copper nitrate, copper sulfate, copper acetate, and hydrates thereof. Furthermore, examples of the aluminum source include alumina hydrates such as aluminum nitrate, pseudoboehmite, boehmite alumina, bayerite, and dibsite, and γ-alumina.

  On the other hand, the silicon source used in the basic aqueous solution is not particularly limited as long as it is soluble in an alkaline aqueous solution and becomes silica upon firing. For example, orthosilicic acid, metasilicic acid and their sodium salts A potassium salt, water glass, etc. are mentioned. Examples of the inorganic base include alkali metal carbonates and hydroxides. Next, the acidic aqueous solution or aqueous dispersion thus prepared and the basic aqueous solution are each heated to about 50 to 90 ° C., mixed together, and further maintained at a temperature of about 50 to 90 ° C. Complete the reaction. Next, the produced solid is sufficiently washed and separated into solid and liquid, or the produced solid is separated into solid and liquid and washed sufficiently, and then this solid is obtained at a temperature of about 80 to 150 ° C. by a known method. Dry at a temperature of The dried product thus obtained is preferably calcined at a temperature in the range of 200 to 400 ° C. to obtain a desulfurization agent having a metal component supported on a silica-alumina support.

When a carrier other than alumina-silica is used as the carrier, it can be carried out according to the above method as appropriate. In order to further reduce the desulfurizing agent obtained by the above-described method so that the amount of metallic nickel is within the scope of the present invention, a method usually used in the art is appropriately used. In the production of hydrogen for a fuel cell, the reduction treatment is performed immediately before the desulfurization treatment step or after the completion of the desulfurization agent production step. When the reduction is performed after the production of the desulfurizing agent, it is preferable that the desulfurizing agent is stabilized using air, diluted oxygen, carbon dioxide, or the like. When this stabilizing treatment desulfurizing agent is used, it is necessary to perform reduction treatment again after filling the desulfurization reactor. After performing the reduction treatment, it may be sealed with an inert gas or desulfurized kerosene.
The desulfurizing agent of the present invention preferably has a hydrogen adsorption amount of 0.15 mmol / g or more. When the hydrogen adsorption amount is 0.15 mmol / g or more, the number of active sites necessary for desulfurization is sufficient, and high desulfurization performance is obtained.

The fuel to be desulfurized using the desulfurizing agent of the present invention is a hydrocarbon raw material and / or an oxygen-containing hydrocarbon raw material, such as kerosene, light oil, liquefied petroleum gas (LPG), naphtha, gasoline, natural gas, dimethyl ether, etc. Or a mixture thereof may be mentioned. Of these, kerosene and liquefied petroleum gas (LPG) are suitable for applying the desulfurizing agent of the present invention. In particular, in kerosene, JIS No. 1 kerosene having a sulfur content of 80 mass ppm or less. Is preferred. This JIS No. 1 kerosene is obtained by desulfurizing crude kerosene obtained by atmospheric distillation of crude oil. The crude kerosene usually has a high sulfur content, and as such, it does not become JIS No. 1 kerosene, Need to be reduced. As a method for reducing the sulfur content, it is preferable to perform a desulfurization treatment by a hydrorefining method which is generally carried out industrially. In this case, as a desulfurization catalyst, usually a mixture of transition metals such as nickel, cobalt, molybdenum, tungsten, etc., mixed at an appropriate ratio is supported on a carrier mainly composed of alumina in the form of metal, oxide, sulfide or the like. Things are used. As the reaction conditions, for example, the reaction temperature is 250 to 400 ° C., the pressure is 2 to 10 MPa · G, the hydrogen / oil molar ratio is 2 to 10, and the liquid hourly space velocity (LHSV) is ^{1 to 5} hr ⁻¹ .

The conditions for desulfurizing the fuel using the desulfurizing agent of the present invention can be appropriately selected according to the properties of the fuel, and are not particularly limited, but can be desulfurized usually in the range of -40 to 300 ° C. When a hydrocarbon such as JIS No. 1 kerosene as a fuel is passed through a desulfurization tower filled with the desulfurization agent of the present invention in a liquid phase in an upward or downward flow, the temperature is about 130 to 230 ° C. The desulfurization treatment is preferably performed under conditions of a pressure of about ¹ Mpa · G and about LHSV 2 hr ⁻¹ or less. At this time, if necessary, a small amount of hydrogen may coexist. By appropriately selecting the desulfurization conditions within the above range, for example, a hydrocarbon having a sulfur content of 3 ppm or less can be obtained.

Next, in the method for producing hydrogen for a fuel cell according to the present invention, the fuel desulfurized as described above is subjected to steam reforming, partial oxidation reforming or autothermal reforming, more specifically steam reforming. Hydrogen for fuel cells is produced by contacting with a catalyst, a partial oxidation reforming catalyst or an autothermal reforming catalyst.
There is no restriction | limiting in particular as a reforming catalyst used here, Arbitrary things can be suitably selected and used from the well-known things conventionally known as a hydrocarbon reforming catalyst. As such a reforming catalyst, for example, a catalyst in which noble metal such as nickel, zirconium, ruthenium, rhodium or platinum is supported on a suitable carrier can be exemplified. The supported metal may be one kind or a combination of two or more kinds. Among these catalysts, those supporting nickel (hereinafter referred to as nickel-based catalyst) and those supporting ruthenium (hereinafter referred to as ruthenium-based catalyst) are preferable. The effect of suppressing carbon deposition during quality treatment or autothermal reforming treatment is great.
The carrier for supporting the reforming catalyst preferably contains manganese oxide, cerium oxide, zirconium oxide or the like, and particularly preferably a carrier containing at least one of these.

In the case of a nickel-based catalyst, the supported amount of nickel is preferably in the range of 3 to 60% by mass based on the carrier. When the supported amount is within the above range, the activity of the steam reforming catalyst, the partial oxidation reforming catalyst or the autothermal reforming catalyst is sufficiently exhibited, and it is economically advantageous. In view of catalyst activity and economy, the more preferable amount of nickel is 5 to 50% by mass, and particularly preferably 10 to 30% by mass.
In the case of a ruthenium-based catalyst, the supported amount of ruthenium is preferably in the range of 0.05 to 20% by mass based on the carrier. When the supported amount of ruthenium is within the above range, the activity of the steam reforming catalyst, the partial oxidation reforming catalyst or the autothermal reforming catalyst is sufficiently exhibited and it is economically advantageous. Considering catalytic activity and economic efficiency, the more preferable loading of ruthenium is 0.05 to 15% by mass, and particularly preferably 0.1 to 2% by mass.

As a reaction condition in the steam reforming treatment, steam / carbon (molar ratio), which is a ratio of steam and carbon derived from fuel oil, is usually selected in the range of 1.5 to 10. When the steam / carbon (molar ratio) is 1.5 or more, the amount of hydrogen generated is sufficient, and when it is 10 or less, excess water vapor is not required, so heat loss is small and hydrogen production can be performed efficiently. . From the above viewpoint, the steam / carbon (molar ratio) is preferably in the range of 1.5 to 5, and more preferably in the range of 2 to 4.
Moreover, it is preferable to perform steam reforming while maintaining the inlet temperature of the steam reforming catalyst layer at 630 ° C. or lower. If the inlet temperature is 630 ° C. or lower, thermal decomposition of the fuel oil does not occur, so that carbon deposition on the catalyst or reaction tube wall via the carbon radical is unlikely to occur. From the above viewpoint, the inlet temperature of the steam reforming catalyst layer is preferably 600 ° C. or lower. The catalyst layer outlet temperature is not particularly limited, but is preferably in the range of 650 to 800 ° C. When the temperature is 650 ° C. or higher, the amount of hydrogen generated is sufficient, and when it is 800 ° C. or lower, the reaction apparatus does not need to be made of a heat-resistant material, which is economically preferable.

As reaction conditions in the partial oxidation reforming treatment, the pressure is usually normal pressure to 5 MPa · G, the temperature is 400 to 1100 ° C., the oxygen (O ₂ ) / carbon (molar ratio) is 0.2 to 0.8, and the liquid The space-time velocity (LHSV) is 0.1 to 100 hr ⁻¹ .
As reaction conditions in the autothermal reforming treatment, the pressure is usually normal pressure to 5 MPa · G, the temperature is 400 to 1100 ° C., the steam / carbon (molar ratio) is 0.1 to 10, and oxygen (O ₂ ). / Carbon (molar ratio) is 0.1 to 1, liquid hourly space velocity (LHSV) is 0.1 to 2 hr ⁻¹ , and gas hourly space velocity (GHSV) is 1000 to 100,000 hr ⁻¹ .
In addition, since CO obtained by the steam reforming, partial oxidation reforming or autothermal reforming adversely affects hydrogen generation, it is preferable to convert CO to CO ₂ by reaction and remove it. Thus, according to the method of the present invention, hydrogen for fuel cells can be produced efficiently.
A fuel cell system using a liquid fuel is usually composed of a fuel supply device, a desulfurization device, a reforming device, and a fuel cell, and the hydrogen produced by the method of the present invention is supplied to the fuel cell.

EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by these examples.
(Physical property measurement method)
(1) Degree of reduction (%)
The degree of reduction was calculated from the amount of hydrogen consumption measured using a temperature programmed reduction (TPR) “TP2000” manufactured by Okura Riken Co., Ltd.
The sample tube was filled with 20 mg of the desulfurization agent (before reduction treatment) produced in each production example, and 100% argon gas was passed for 1 hour to replace the air. Thereafter, a mixed gas of hydrogen (65%) / argon (35%) was circulated at 20 cm ³ / min and held at room temperature for 90 minutes. Next, the hydrogen consumption was measured with a TCD detector (heat conduction type detector) while heating to 827 ° C. at a rate of temperature increase of 10 ° C./min. FIG. 1 is a TPR profile of a desulfurization agent (before reduction treatment), and the peak area A shown in FIG. 1 indicates the amount of hydrogen necessary for the total reduction of the metal component from the oxide to the metal state.
Next, after reducing and stabilizing the desulfurizing agent produced in each Example and Comparative Example, the hydrogen consumption of the desulfurizing agent was measured in the same manner as described above. The result shows the TPR profile shown in FIG. 2, and the hydrogen consumed in the vicinity of 400 K (127 ° C.) in FIG. 2 (corresponding to the peak area C) is due to re-reduction of the surface oxidized portion by the stabilization treatment. The hydrogen consumed in the vicinity of 770 K (497 ° C.) (corresponding to the peak area B) is due to the reduction of the unreduced portion after the reduction treatment. From these, the degree of reduction was determined by the following equation.
Degree of reduction (%) = 100 × (area A−area B) / area A
(2) Metal crystallite diameter The metal crystallite diameter was measured as follows using X-ray diffractometer "RAD-B" manufactured by Rigaku Corporation.
The sample plate was filled with the desulfurization agent subjected to reduction / stabilization treatment manufactured in each Example and Comparative Example, and using copper Kα ray (wavelength λ = 0.15405 nm) as an X-ray source, diffraction angle 2θ X-ray diffraction pattern was obtained by sweeping from 5 to 80 degrees (FIG. 3). The peak separation of the pattern was performed, and the half width β (rad) of the peak derived from the metal having 2θ of around 52 degrees was calculated, and the metal crystallite diameter was determined by the following formula.
Metal crystallite diameter (nm) = 0.9λ / ((β−b) · cos θ)
(B: Peak broadening (rad) by the optical system of the apparatus)

(Evaluation methods)
By the desulfurization test of kerosene and liquefied petroleum gas (LPG), the desulfurization performance of the desulfurization agents produced in Examples 1 to 5 and Comparative Examples 1 to 3 was evaluated.
(1) Desulfurization test of kerosene 15 cm ³ of the desulfurizing agent produced in each example and comparative example was filled in a SUS reaction tube having an inner diameter of 17 mm. Under normal pressure, the temperature was raised to 200 ° C. in a hydrogen stream and maintained at that temperature for 2 hours to activate the desulfurizing agent. Next, JIS-1 kerosene having the properties shown in Table 1 was circulated through the reaction tube at 200 ° C., pressure 0.6 MPa, and liquid space velocity (SV) 20 h ⁻¹ . Desulfurization performance was evaluated by the sulfur concentration after 30 hours.

(2) Desulfurization test of liquefied petroleum gas (LPG) 15 cm ³ of the desulfurizing agent produced in Example 1 was charged into a SUS reaction tube having an inner diameter of 17 mm. Under normal pressure, the temperature was raised to 200 ° C. in a hydrogen stream and maintained for 2 hours to activate the desulfurizing agent. Thereafter, the temperature was lowered to 180 ° C. and kept at that temperature. Subsequently, JIS-1 type-1 No. LPG having the properties shown in Table 2 was circulated through the reaction tube at a gas space velocity (SV) of 4000 h ^-1 under normal pressure. The sulfur concentration after elapse of 800 hours was analyzed to evaluate the desulfurization performance.

Production Example 1
Ion exchange in which 730.2 g of nickel sulfate hexahydrate (special grade, manufactured by Wako Pure Chemical Industries, Ltd.) and 151.3 g of copper sulfate pentahydrate (special grade, manufactured by Wako Pure Chemical Industries, Ltd.) were heated to 80 ° C. It was dissolved in water 8L, which pseudoboehmite (C-AP, 67 wt% as Al ₂ O _3, manufactured by catalysts & Chemicals Industries Co., Ltd.) was 16.0g mixed. To this, 300 mL of 1N sulfuric acid was added to adjust the pH to 2, whereby Preparation Solution X was obtained.
Next, 600.0 g of sodium carbonate was dissolved in 8 L of ion-exchanged water heated to 80 ° C. separately, and 180.2 g of water glass (No. J-1, Si concentration 29 mass%, Nippon Chemical Industry Co., Ltd.) Preparation liquid Y was obtained.
While maintaining the temperature of each of the preparation liquids X and Y at 80 ° C., both were mixed and stirred for 1 hour to obtain a precipitation cake. Thereafter, the precipitate cake obtained using 60 L of ion-exchanged water was washed and filtered, and the product was dried for 12 hours in a 120 ° C. blower dryer and then calcined at 350 ° C. for 3 hours. Thereafter, the fired product was molded by tableting and pulverized to obtain a desulfurization agent a having an average particle size of 0.8 mm.
The nickel content (NiO equivalent) of the desulfurizing agent a is 65% by mass, the copper content (CuO equivalent) is 15% by mass, the amount of silica-alumina as a support is 20% by mass, and the Si / Al ratio (atomic ratio) is 5.6.

Production Example 2
A desulfurizing agent b was obtained in the same manner as in Production Example 1, except that the amount of nickel sulfate hexahydrate charged was 808.8 g and the amount of copper sulfate pentahydrate charged was 80.7 g.
The desulfurization agent b has a nickel content (NiO equivalent) of 72% by mass, a copper content (CuO equivalent) of 8% by mass, the amount of silica-alumina as a support is 20% by mass, and the Si / Al ratio (atomic ratio) is 5.6.

Example 1
The desulfurizing agent a prepared in Production Example 1 was heated to 180 ° C. in a hydrogen stream under normal pressure, held for 6 hours, further heated to 300 ° C. over 30 minutes, held at the temperature for 50 hours, Reduction was performed. Next, the temperature was lowered to room temperature, and the outermost surface oxidation treatment (stabilization treatment) of the desulfurizing agent was performed with diluted oxygen (oxygen concentration 1%). About the desulfurization agent a which performed such a process, the reduction degree and the metal crystallite diameter were measured with the said physical-property measuring method, and the desulfurization activity was evaluated with the said evaluation method. The results are shown in Tables 3 and 4.
Example 2
The desulfurization agent b produced in Production Example 2 was reduced and stabilized in the same manner as in Example 1, and the degree of reduction and metal crystallite diameter were measured and the desulfurization activity was evaluated. The results are shown in Tables 3 and 4.

Example 3
The desulfurizing agent a prepared in Production Example 1 was heated to 180 ° C. in a hydrogen stream under normal pressure, held for 6 hours, further heated to 400 ° C. over 30 minutes, held at the temperature for 20 hours, Reduction was performed. Immediately thereafter, the outermost surface oxidation treatment (stabilization treatment) of the desulfurizing agent was performed with diluted oxygen (oxygen concentration 1%). About the desulfurization agent a which performed such a process, the reduction degree and the metal crystallite diameter were measured with the said physical-property measuring method, and the desulfurization activity was evaluated with the said evaluation method. The results are shown in Tables 3 and 4.
Example 4
The desulfurizing agent b produced in Production Example 2 was subjected to reduction and stabilization treatment in the same manner as in Example 3, and the degree of reduction and metal crystallite diameter were measured and the desulfurization activity was evaluated. The results are shown in Tables 3 and 4.

Comparative Example 1
The desulfurizing agent a prepared in Production Example 1 was heated to 180 ° C. in a hydrogen stream under normal pressure, held for 6 hours, further heated to 300 ° C. over 30 minutes, held at that temperature for 3 hours, Reduction was performed. Immediately thereafter, the outermost surface oxidation treatment (stabilization treatment) of the desulfurizing agent was performed with diluted oxygen (oxygen concentration 1%). About the desulfurization agent a which performed such a process, the reduction degree and the metal crystallite diameter were measured with the said physical-property measuring method, and the desulfurization activity was evaluated with the said evaluation method. The results are shown in Tables 3 and 4.
Comparative Example 2
The desulfurization agent b produced in Production Example 2 was reduced and stabilized in the same manner as in Comparative Example 1, and the degree of reduction and metal crystallite diameter were measured and the desulfurization activity was evaluated. The results are shown in Tables 3 and 4.

Comparative Example 3
The desulfurizing agent a prepared in Production Example 1 was heated to 180 ° C. in a hydrogen stream under normal pressure, held for 6 hours, further heated to 500 ° C. over 30 minutes, held at that temperature for 3 hours, Reduction was performed. Immediately thereafter, the outermost surface oxidation treatment (stabilization treatment) of the desulfurizing agent was performed with diluted oxygen (oxygen concentration 1%). About the desulfurization agent a which performed such a process, the reduction degree and the metal crystallite diameter were measured with the said physical-property measuring method, and the desulfurization activity was evaluated with the said evaluation method. The results are shown in Tables 3 and 4.
Comparative Example 4
The desulfurization agent b produced in Production Example 2 was reduced and stabilized in the same manner as in Comparative Example 3, and the degree of reduction and metal crystallite diameter were measured and the desulfurization activity was evaluated. The results are shown in Tables 3 and 4.

  The desulfurization agent of the present invention is an industrially advantageous desulfurization agent that can efficiently remove the sulfur content in the hydrocarbon raw material and / or the oxygen-containing hydrocarbon raw material to a very low concentration and has a long life. Accordingly, when applied to a desulfurization device of a normal fuel cell system composed of a fuel supply device, a desulfurization device, a reformer, and a fuel cell, the catalyst of the reformer can be kept highly active for a long period of time. And hydrogen for a fuel cell can be produced efficiently. Moreover, it is a desulfurization agent applicable also to desulfurization of hydrogen or city gas to which an odorant composed of a sulfur compound is added.

TPR profile of desulfurizing agent (before reduction treatment) TPR profile of desulfurization agent (after reduction and stabilization) X-ray diffraction chart of desulfurization agent (after reduction treatment and stabilization treatment)

Claims (11)

  A desulfurization agent for removing a sulfur compound in a hydrocarbon raw material and / or an oxygen-containing hydrocarbon raw material obtained by supporting a metal component on a carrier, wherein 80 mol% or more of the metal component is in a metallic state, and a metal crystal A desulfurizing agent having a child diameter of 4.0 nm or less.   The desulfurization agent according to claim 1, wherein nickel is contained as a metal component, and the nickel content is in a range of 50 to 90 mass% as a conversion amount of NiO (nickel oxide) with respect to the total amount of the desulfurization agent.   The desulfurization agent according to claim 1 or 2, which contains copper as a metal component, and the copper content is 40% by mass or less in terms of CuO (copper oxide) with respect to the total amount of the desulfurization agent.   The desulfurization agent according to any one of claims 1 to 3, wherein the carrier contains at least one selected from silica, alumina, and silica-alumina.   The hydrocarbon raw material and / or the oxygen-containing hydrocarbon raw material is at least one selected from kerosene, light oil, liquefied petroleum gas (LPG), naphtha, gasoline, natural gas, and dimethyl ether. Desulfurization agent.   A desulfurization method comprising desulfurizing a hydrocarbon raw material and / or an oxygen-containing hydrocarbon raw material at a temperature in the range of -40 to 300 ° C using the desulfurizing agent according to any one of claims 1 to 5.   A method for producing hydrogen for a fuel cell, comprising desulfurizing a hydrocarbon feedstock and / or an oxygen-containing hydrocarbon feedstock using the desulfurizing agent according to any one of claims 1 to 6.   The method for producing hydrogen for a fuel cell according to claim 7, wherein the reforming is steam reforming, partial oxidation reforming, or autothermal reforming.   The method for producing hydrogen for a fuel cell according to claim 7 or 8, wherein the catalyst used for reforming is a ruthenium catalyst or a nickel catalyst.   The method for producing hydrogen for a fuel cell according to claim 9, wherein the carrier component of the catalyst used for reforming contains at least one selected from manganese oxide, cerium oxide, and zirconium oxide. 11. A fuel cell system using hydrogen produced by the method according to claim 7.

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