JP5419095B2 - Hydrocarbon desulfurization agent - Google Patents

Description

  The present invention relates to a hydrocarbon desulfurization agent used as a reforming raw material for producing hydrogen in hydrocarbons, particularly in 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. As the hydrogen source of this fuel cell, 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 further LPG, naphtha, kerosene, etc. There are various hydrocarbons, such as petroleum-based fuels, and their use is being studied.

  When hydrogen is produced using these hydrocarbons, generally, a method is used in which the hydrocarbon is subjected to steam reforming or partial oxidation reforming treatment in the presence of a reforming catalyst. However, these hydrocarbons contain a sulfur content, and the reforming catalyst is poisoned by the sulfur content in the hydrocarbons. This is because an active metal such as nickel or ruthenium generally used for the reforming catalyst has low resistance to sulfur. Therefore, when the raw material hydrocarbon contains a sulfur content, from the viewpoint of the life of the reforming catalyst, it is required that the hydrocarbon be subjected to a desulfurization treatment in advance to make the sulfur content normally 100 mass ppb or less.

As a general desulfurization method, there are many so-called hydrodesulfurization methods in which sulfur compounds are removed in the form of hydrogen sulfide with a cobalt-molybdenum or nickel-molybdenum-based catalyst in a hydrogen atmosphere of 200 to 400 ° C. and 2 to 15 MPa. Used (see, for example, Patent Document 1). Such hydrogen desulfurization methods using hydrocarbons (kerosene, etc.) have been actively researched for a long time, but high-temperature and high-pressure conditions are necessary when reducing the sulfur content of raw material hydrocarbons by hydrodesulfurization methods. It is economically disadvantageous because there are certain things and hydrogen is required separately. In addition, this hydrodesulfurization method has not yet achieved desulfurization to a level sufficient to protect the reforming catalyst from poisoning.
Therefore, in the stationary fuel cell power generation system, various techniques for desulfurizing commercially available hydrocarbons by adsorption on-site have been proposed, and hydrocarbons, especially heavy hydrocarbons such as kerosene, are reacted under reaction conditions around 200 ° C. A method of desulfurization using a Ni—Cu-based desulfurizing agent or a Ni—Zn-based desulfurizing agent has been proposed (for example, see Patent Documents 2 and 3).

However, some conventional Ni-based desulfurization agents may break through in a relatively short time (the sulfur concentration of the product oil exceeds the standard value), and the life of the desulfurization agent is not sufficient. Extending the time to reach breakthrough (breakthrough time) is desired from the viewpoint of reducing the frequency of replacement of the desulfurizing agent and reducing the size and efficiency of the apparatus.
Therefore, the present applicant previously proposed that the breakthrough time can be greatly extended by using a Ni-Mo-based desulfurization agent as compared with other desulfurization agents not containing Mo (patent document). 4). However, it is desired to provide a desulfurization agent having further excellent desulfurization performance from the viewpoint of reducing the frequency of desulfurization agent replacement and reducing the size and efficiency of the apparatus.

JP-A-6-91173 JP 2004230317 A JP 2003-290660 A JP 2007-254275 A

  In view of the above-described conventional situation, the present invention can further efficiently remove sulfur in hydrocarbons to a low concentration of ppb level without supplying hydrogen together with hydrocarbons, and the breakthrough time is extended. An object of the present invention is to provide a hydrocarbon desulfurization agent having a long life.

The inventors of the present invention have made extensive studies on desulfurization by adsorption of hydrocarbons in order to achieve the above object. By using a desulfurization agent having a specific composition containing calcium in addition to nickel and molybdenum, the breakthrough time in the desulfurization reaction can be achieved. The present invention has been found based on this finding. That is, the present invention relates to the following hydrocarbon desulfurization agent.
1. Nickel is 50 to 95% by mass in terms of oxide (NiO), molybdenum is 0.5 to 25% by mass in terms of oxide (MoO ₃ ), calcium is 0.1 to 3% by mass in terms of oxide (CaO), And a hydrocarbon desulfurization agent characterized by containing an inorganic oxide.
2. Inorganic _{oxide, SiO 2, Al 2 O 3} , and hydrocarbon desulfurizing agent according to the above 1 is at least one or more _SiO 2 _-Al 2 _{O 3.}
3. Using the desulfurization agent according to 1 or 2 above, the sulfur content in the hydrocarbon is 50 masses under the conditions of a reaction temperature of 0 to 400 ° C., a reaction pressure of 0.1 MPa or more, and a liquid space velocity of 0.01 to 100 hr ^−1. A hydrocarbon desulfurization method of ppb or less.

  By having a specific composition, the desulfurization agent of the present invention can remove sulfur in hydrocarbons such as kerosene, jet fuel, naphtha, gasoline, LPG, and natural gas very efficiently, and remarkably increases the breakthrough time of 50 mass ppb. It is a long-life hydrocarbon desulfurization agent that can be used. Moreover, since calcium added to nickel and molybdenum is relatively inexpensive, it is possible to suppress a significant increase in manufacturing cost compared to Ni—Mo-based desulfurization agents.

<Desulfurization agent composition>
The desulfurizing agent in the present invention contains nickel, molybdenum and calcium, and adsorbs and removes sulfur-containing compounds present in the raw material hydrocarbon to reduce (desulfurize) the sulfur concentration in the raw material hydrocarbon.
In the present invention, by adding calcium to the desulfurizing agent, it is possible to suppress carbon deposition on the desulfurizing agent as compared with the case where it is not added, the carbon coating on the metal component is reduced, and the metal component is deteriorated. As a result, it is estimated that the breakthrough time becomes longer.

  The content of nickel in the desulfurizing agent is 50 to 95% by mass, preferably 60 to 90% by mass in terms of oxide (NiO). If the amount of nickel oxide is 50% by mass or more, the desired desulfurization performance is exhibited, and if it is 95% by mass or less, the desulfurization effect is not saturated, and the desulfurization performance is not easily lowered due to the aggregation of Ni. Therefore, it is preferable.

The content of molybdenum in the desulfurizing agent is 0.5 to 25% by mass, preferably 0.5 to 20% by mass in terms of oxide (MoO ₃ ). If the amount of molybdenum oxide is 0.5% by mass or more, the desired desulfurization performance is exhibited, and if it is 25% by mass or less, the desulfurization effect is not saturated and the desulfurization performance is not easily lowered.

  The content of calcium in the desulfurizing agent is 0.1 to 3% by mass, preferably 0.5 to 2.5% by mass in terms of oxide (CaO). If the amount of molybdenum oxide is 0.1% by mass or more, the desired desulfurization performance is exhibited, and if it is 3% by mass or less, the desulfurization effect is not saturated and the desulfurization performance is not easily lowered. When calcium is added in an amount exceeding 3% by mass in terms of oxide (CaO), although there is an effect of suppressing carbon deposition, the specific surface area and bulk density of the desulfurizing agent decrease, resulting in a decrease in performance. Presumed to be.

The desulfurizing agent of the present invention further contains an inorganic oxide in addition to the nickel, molybdenum and calcium. When an inorganic oxide is used, the adsorptive active metal is dispersed and attached to the oxide, thereby improving the dispersibility, improving the desulfurization performance, and extending the breakthrough time. Also, since the moldability and strength of the desulfurizing agent are improved, it is desirable to use an inorganic oxide in order to obtain a highly active and highly durable desulfurizing agent.
The kind of the inorganic oxide is not particularly limited, but an oxide of any one element selected from the group consisting of Si, Al, B, Mg, Ce, Zr, P, Ti, W, Mn, or a mixture thereof, Alternatively, a composite oxide of two or more elements is preferable, and these may have an amorphous or crystalline structure. For _{example, SiO 2, Al 2 O 3} , TiO 2, B 2 O 3, MgO, SiO 2 -Al 2 O 3, Al 2 O 3 -B 2 O 3, MgO-SiO 2, etc. zeolites. Among various inorganic oxides, SiO ₂ , Al ₂ O ₃ , and SiO ₂ —Al ₂ O ₃ are particularly preferable because they have a high surface area, high moldability, and high fracture resistance and wear resistance. Incidentally, the _SiO 2 _-Al 2 _{O 3} can be produced in the process of firing the mixture containing both Si source and Al source in the firing step described later desulfurizing agent.
About content of an inorganic oxide component, there is no restriction | limiting in particular, What is necessary is just to select suitably in various conditions, Usually, preferably 0.5-50 mass% with respect to the whole desulfurization agent, More preferably, 0.5- It may be in the range of 40% by mass, more preferably 0.5-30% by mass. If the content is 0.5% by mass or more, the effect as an inorganic oxide component is sufficiently exhibited, and if it is 50% by mass or less, a decrease in desulfurization performance due to a decrease in the adsorption active component can be prevented. ,preferable.

  Furthermore, in the desulfurizing agent of the present invention, it is preferable that the above-mentioned contained metal is reduced to a metal state suitable for the desulfurization reaction before the desulfurization reaction. Thereby, the contained metal is activated and the sulfur adsorption ability of the desulfurizing agent can be improved. In order to make the metal contained in the desulfurizing agent into a metallic state, reduction treatment with hydrogen or the like may be performed before use. The state of the metal can be confirmed by measuring the peak of each metal by X-ray diffraction (XRD). For example, the presence of metallic nickel can be confirmed by detecting a diffraction peak having a peak top in the vicinity of 2θ = 51.6 ° by X-ray diffraction measurement (ray source Cu—Kα ray).

Moreover, it is preferable that it is 150-600 m < ² > / g, and, as for the specific surface area of the desulfurization agent of this invention before a reduction process, it is more preferable that it is 180-500 m < ² > / g. If the specific surface area is 150 m ² / g or more, the number of adsorption points for adsorbing sulfur increases, and a sufficient adsorption capacity is obtained, which is preferable. Moreover, if a specific surface area is 600 m < ² > / g or less, an average pore diameter becomes comparatively large and sufficient adsorption capacity is obtained and it is preferable.

  The shape of the desulfurizing agent is not particularly specified, and it may be in any state such as a molded body (extruded cylinder, tablet cylinder, sphere, etc.), a granular body sieved with a mesh, or a powder, but considering the ease of handling Granules sieved with a molded body or mesh are preferred. In order to make the shape of the desulfurizing agent into a molded body or a granular body sieved with a mesh, it is desirable to use an inorganic oxide. Further, the size of the desulfurizing agent is not particularly limited regardless of the size of the molded product or the granular material sieved with a mesh, but usually the diameter or length is 0.1 to 10 mm, more preferably 0.1 to 5 mm. It is preferable that

<Preparation of desulfurizing agent>
The method for preparing the desulfurizing agent is not particularly defined and can be appropriately prepared by any method, but it is prepared by an impregnation method, a kneading method, a coprecipitation method, a sol-gel method, an equilibrium adsorption method, etc. using an inorganic oxide. An impregnation method and a coprecipitation method are preferable for effectively functioning nickel, molybdenum and calcium. Further, for the addition of nickel, the coprecipitation method is more preferable because the impregnation method requires a small amount of support by one operation.

  Although the suitable manufacturing method of the desulfurization agent of this invention is demonstrated concretely below, the manufacturing method of the desulfurization agent of this invention is not limited to this.

[Ni, Mo, Ca coprecipitation (1)]
A first method for preparing a suitable desulfurizing agent of the present invention will be described. In this method, first, an acidic aqueous solution containing a nickel raw material and a calcium raw material and a basic aqueous solution containing a molybdenum raw material are separately prepared. The inorganic oxide raw material can be added to either an acidic aqueous solution or a basic aqueous solution. When using 2 or more types of inorganic oxide raw materials, you may add an inorganic oxide raw material to both aqueous solution.

For example, when producing a desulfurization agent containing SiO ₂ and Al ₂ O ₃ as an inorganic oxide, an acidic aqueous solution containing nickel raw material, calcium raw material and aluminum raw material, and a basic aqueous solution containing molybdenum raw material, Si raw material and inorganic base Are prepared respectively. In the production of the desulfurizing agent containing only SiO ₂ as the inorganic oxide, for example, an acidic aqueous solution containing a nickel raw material and calcium material, to prepare respectively a basic aqueous solution containing a molybdenum material, Si raw material and an inorganic base.

Although it does not specifically limit as a nickel raw material, Water-soluble nickel metal salts, such as nickel nitrate, nickel sulfate, nickel chloride, nickel acetate, and its hydrate can be used conveniently. Although it does not specifically limit as a calcium raw material, Calcium metal salts, such as calcium nitrate and calcium sulfate, and its hydrate can be used conveniently. These nickel raw material, molybdenum raw material, and calcium raw material may be used alone or in combination of two or more.
Further, the aluminum raw material is not particularly limited, but boehmite, pseudoboehmite, γ alumina, β alumina and the like are preferable. These can be used in the form of powder or sol, and may be used alone or in combination of two or more.
The acidic aqueous solution is preferably prepared with an acid such as hydrochloric acid, sulfuric acid, or nitric acid.

Although it does not specifically limit as a molybdenum raw material, Water-soluble molybdenum metal salts, such as ammonium molybdate and molybdophosphoric acid, and its hydrate can be used conveniently.
Further, the Si raw material is not particularly limited, but silica, water glass, sodium metasilicate, diatomaceous earth, mesoporous silica (MCM41) and the like are preferable.
And as an inorganic base, an alkali metal carbonate, a hydroxide, etc. are preferable, for example, sodium carbonate, sodium hydrogencarbonate, potassium carbonate, sodium hydroxide, potassium hydroxide etc. are mentioned, Especially sodium carbonate is suitable. .
The amount of the inorganic base used is advantageously selected so that the mixed solution of the acidic aqueous solution and the basic aqueous solution is substantially neutral to basic in the next step. Si raw material and inorganic base may be used independently and may be used in combination of 2 or more types.

  The aluminum raw material and Si raw material are used for adding an inorganic oxide component to the desulfurization agent. The same applies to the second and third methods described later.

  Next, each prepared aqueous solution is heated at 25-90 degreeC, respectively, and both are mixed. And it stirs about 0.5 to 3 hours, hold | maintaining liquid temperature at 25-90 degreeC, and completes reaction. The pH after mixing the acidic aqueous solution and the basic aqueous solution is preferably 6 or more, more preferably in the range of 6 to 11, and still more preferably in the range of 6.5 to 10. A pH of 6 or more is preferable because nickel, molybdenum and calcium precipitate efficiently. Moreover, since the usage-amount of an inorganic base can be saved that pH is 11 or less, it is preferable from a manufacturing cost side.

After the precipitate of the reacted aqueous solution is filtered and washed with water, the solid is dried at a temperature of about 50 to 150 ° C. by a known method. The dried product thus obtained is preferably fired at a temperature in the range of 200 to 450 ° C. for 1 to 5 hours.
As described above, the desulfurization agent of the present invention can be suitably prepared.

[Ni, Mo, Ca coprecipitation (2)]
Next, a second method for preparing a suitable desulfurizing agent of the present invention will be described. In this method, first, an acidic aqueous solution containing a nickel raw material, a calcium raw material and a molybdenum raw material and a basic aqueous solution containing an inorganic oxide raw material are separately prepared. When using 2 or more types of inorganic oxide raw materials, an inorganic oxide raw material can also be added to acidic aqueous solution.

For example, when producing a desulfurization agent containing SiO ₂ and Al ₂ O ₃ as an inorganic oxide, an acidic aqueous solution containing a nickel raw material, a calcium raw material, a molybdenum raw material and an aluminum raw material, and a basic aqueous solution containing a Si raw material and an inorganic base Are prepared respectively.
As the nickel raw material, the calcium raw material, the molybdenum raw material, the aluminum raw material, the Si raw material, and the inorganic base, those similar to the first method can be used. Moreover, it is preferable to prepare acidic aqueous solution containing nickel raw material, calcium raw material, molybdenum raw material, and aluminum raw material with acids, such as hydrochloric acid, a sulfuric acid, and nitric acid. The pH after mixing the acidic aqueous solution and the basic aqueous solution is preferably in the same range as the pH described in the first method.
The prepared acidic aqueous solution and basic aqueous solution are mixed under the same conditions as in the first method to complete the reaction. The formed precipitate is filtered, washed with water, dried, and the dried product is fired. .
Even if it does as mentioned above, the desulfurization agent of this invention can be prepared suitably.

[Ni, Ca coprecipitation, Mo impregnation]
Furthermore, a third method for preparing a suitable desulfurizing agent of the present invention will be described. In this method, first, an acidic aqueous solution containing a nickel raw material and a calcium raw material and a basic aqueous solution containing an inorganic oxide raw material are separately prepared. When using 2 or more types of inorganic oxide raw materials, an inorganic oxide raw material can also be added to acidic aqueous solution.

For example, in the case of producing a desulfurization agent containing SiO ₂ and Al ₂ O ₃ as inorganic oxides, an acidic aqueous solution containing nickel raw material, calcium raw material and aluminum raw material, and a basic aqueous solution containing Si raw material and inorganic base are prepared. To do.
As the nickel raw material, the calcium raw material, the aluminum raw material, the Si raw material, and the inorganic base, those similar to the first method can be used. Moreover, it is preferable to prepare acidic aqueous solution containing a nickel raw material, a calcium raw material, and an aluminum raw material with acids, such as hydrochloric acid, a sulfuric acid, and nitric acid. The pH after mixing the acidic aqueous solution and the basic aqueous solution is preferably in the same range as the pH described in the first method.
The prepared acidic aqueous solution and basic aqueous solution are mixed under the same conditions as in the first method to complete the reaction. The formed precipitate is filtered, washed with water, dried, and the dried product is fired. .

The obtained fired product is impregnated with an aqueous solution obtained by dissolving a molybdenum raw material in ion-exchanged water. If the molybdenum raw material is not dissolved in ion-exchanged water, a small amount of ammonia water may be added. As the molybdenum raw material, the same material as in the first method can be used.
The obtained impregnated product of molybdenum raw material aqueous solution is dried at a temperature of about 50 to 150 ° C. by a known method, and the dried product is preferably fired at a temperature in the range of 200 to 450 ° C. for 1 to 5 hours. .
Even if it does as mentioned above, the desulfurization agent of this invention can be prepared suitably.

<Desulfurization method>
The desulfurization agent of the present invention prepared as described above is preferably subjected to a reduction treatment before being subjected to a desulfurization reaction. As a result, the metal contained in the desulfurizing agent is activated and the sulfur component is easily adsorbed. As the reduction method, a known method such as gas phase reduction using hydrogen, CO, etc., liquid phase reduction using formaldehyde, ethanol, or the like can be used, but hydrogen reduction by gas phase is preferable, and in this case, hydrogen reduction It is preferable to carry out at 200-500 degreeC by atmosphere, and it is more preferable to carry out at the temperature of 300-450 degreeC.
The hydroreduction treatment can be performed in the actual desulfurizer (on-site) or in advance in the hydro-reduction treatment device (off-site), but the heat resistance of the desulfurizer to be used can be improved. Considering off-site reduction is preferred. Further, in the off-site hydroreduction treatment, it is more preferable to perform a stabilization treatment with oxygen, carbon dioxide or the like in order to improve the stability of the desulfurizing agent after the reduction treatment.

  In order to desulfurize hydrocarbons using the desulfurizing agent of the present invention, desulfurization is usually performed by filling the adsorption tank with a desulfurizing agent and contacting the raw material hydrocarbon with the desulfurizing agent in the adsorption tank. As a method for bringing hydrocarbons into contact with the desulfurizing agent, generally, a fixed bed type desulfurizing agent bed is formed in the adsorption tank, the raw material is introduced into the lower part of the adsorption tank, and passed from below the fixed bed to above. The product oil can be discharged from the upper part of the adsorption tank.

The conditions for the desulfurization reaction are not particularly specified, but the pressure is preferably normal pressure (0.1 MPa) or more, more preferably 0.1 to 1.1 MPa. In order to reduce the pressure to 0.1 MPa or less, special equipment such as a decompression device is required, which is not economically preferable. On the other hand, if the pressure is set to 1.1 MPa or more, the pressure resistance of the desulfurizer or the supply pump is required, which is not economical.
Moreover, 0-400 degreeC is preferable, More preferably, it is 100-300 degreeC, More preferably, it is 140-300 degreeC. If the temperature is too low, the adsorptive desulfurization rate decreases. On the other hand, if the temperature is too high, the nickel component in the desulfurizing agent aggregates and the number of desulfurization sites decreases, which may reduce the desulfurization performance.
Also, liquid hourly space velocity (LHSV) 0.01～100Hr ^-1, more preferably 0.1 to 20 ^-1.

Kerosene, jet fuel, naphtha, gasoline, LPG and natural gas are preferred as the hydrocarbon used as a raw material, and kerosene is particularly preferred from the viewpoint of market distribution and ease of handling. Kerosene can be desulfurized as desired with the desulfurizing agent of the present invention as long as the sulfur content is about 80 ppm by mass. Usually, kerosene having a sulfur content of 50 mass ppm or less, preferably 30 mass ppm or less, more preferably 10 mass ppm or less is used.
Further, the aromatic content in kerosene is usually preferably 30 vol% or less, and more preferably 20 vol% or less. When the aromatic content in kerosene is 30 vol% or less, the sulfur content is more easily reduced. The 95% point in the distillation properties of kerosene is usually preferably 270 ° C. or lower. By appropriately selecting the desulfurization conditions within the above range, a hydrocarbon having a sulfur content reduced to the ppb level can be obtained for a long time.

EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by these examples.
The physical properties of the desulfurizing agent in Examples and Comparative Examples, the instrumental analysis method for the sulfur content in the hydrocarbon (produced oil), and the method for measuring the carbon deposition amount are shown below.

<Measurement of specific surface area of desulfurization agent>
A BET surface area measuring device (Belsorb Mini) was used for measurement of BET (Braunauer-Emmett-Tailor specific surface area) specific surface area. About 200 to 300 mg of the sample was precisely weighed, filled in a quartz sample tube, heated from room temperature to 400 ° C. over 1 hour while reducing the pressure on the order of 10 ⁻¹ to 10 ⁻³ mmHg, The deaeration treatment was performed by maintaining at the same temperature for 3 hours. Thereafter, the temperature was lowered to room temperature while reducing the pressure, the gas was replaced with high purity helium gas, and the weight of the sample after deaeration was precisely weighed. Thereafter, nitrogen adsorption was performed at the liquefied nitrogen temperature, and the specific surface area was measured.

<Sulfur analysis in hydrocarbons>
For analysis of sulfur in hydrocarbons, Thermo Onix XVI manufactured by HOUSTON ATLAS was used.

<X-ray diffraction analysis method of desulfurization agent>
An X-ray diffractometer (RINT-2500V) manufactured by Rigaku Corporation was used. The sample to be measured is pulverized and packed in a sample plate. X-ray diffraction (scanning range 5 to 90 °, sample rotation speed 20 rpm, divergence slit 1 °, scattering slit 1 °, light receiving slit 1 °, scan speed 2 ° / min) (Source Cu—Kα ray) measurement was performed.

<Measurement of carbon deposition amount on desulfurization agent>
For the measurement of carbon content, an organic trace element analyzer (JM10) manufactured by J Science Lab Co., Ltd. was used. After preparing a calibration curve using a standard sample, about 1 mg to 5 mg of a sample was collected and measured.

Example 1 Ni, Mo, Ca coprecipitation (1) (first method)
1.24 g of boehmite AP-3 (manufactured by Catalyst Kasei Kogyo Co., Ltd.) was added to 1 L of ion exchange water and heated to 80 ° C., then 126.5 g of NiSO ₄ .6H ₂ O, Ca (NO ₃ ) ₂ .4H ₂ O 3.0 g was added to obtain Preparation A. Separately prepared ion-exchanged water 1L colloidal silica Snowtex XS (Nissan Chemical Industries, Ltd.) 33.9 g, sodium carbonate _{59.4g, (NH 4) 6 Mo} 7 O 24 · 5H 2 O was added 3.9 g, Heated to 80 ° C. to obtain Preparation B. While maintaining the preparation liquid A and the preparation liquid B at 80 ° C., the liquid B was instantaneously added to the liquid A and stirred for 1 hour. Then, using 5 L of ion-exchanged water, washed and filtered, dried in air at 120 ° C. for 12 hours, and fired at 400 ° C. for 1 hour. The resulting fired product was crushed, and 1.0 mm and 1.4 mm meshes were obtained. The desulfurization agent 1 was obtained by sieving with a sieve having the same.

Example 2: Ni, Mo, Ca coprecipitation (1) (first method)
1.24 g of boehmite AP-3 (manufactured by Catalyst Kasei Kogyo Co., Ltd.) was added to 1 L of ion exchange water and heated to 80 ° C., then 126.5 g of NiSO ₄ .6H ₂ O, Ca (NO ₃ ) ₂ .4H ₂ O Was added to obtain Preparation Liquid A. Separately prepared ion-exchanged water 1L colloidal silica Snowtex XS (Nissan Chemical Industries, Ltd.) 33.9 g, sodium carbonate _{59.4g, (NH 4) 6 Mo} 7 O 24 · 5H 2 O was added 3.9 g, Heated to 80 ° C. to obtain Preparation B. While maintaining the preparation liquid A and the preparation liquid B at 80 ° C., the liquid B was instantaneously added to the liquid A and stirred for 1 hour. Then, using 5 L of ion-exchanged water, washed and filtered, dried in air at 120 ° C. for 12 hours, and fired at 400 ° C. for 1 hour. The resulting fired product was crushed, and 1.0 mm and 1.4 mm meshes were obtained. The resulting product was sieved with a sieve having a desulfurizing agent 2.

Example 3 Ni, Mo, Ca coprecipitation (1) (first method)
1.24 g of boehmite AP-3 (manufactured by Catalyst Kasei Kogyo Co., Ltd.) was added to 1 L of ion exchange water and heated to 80 ° C., then 126.5 g of NiSO ₄ .6H ₂ O, Ca (NO ₃ ) ₂ .4H ₂ O Was added to obtain Preparation Liquid A. Separately prepared ion-exchanged water 1L colloidal silica Snowtex XS (Nissan Chemical Industries, Ltd.) 33.9 g, sodium carbonate _{59.4g, (NH 4) 6 Mo} 7 O 24 · 5H 2 O was added 3.9 g, Heated to 80 ° C. to obtain Preparation B. While maintaining the preparation liquid A and the preparation liquid B at 80 ° C., the liquid B was instantaneously added to the liquid A and stirred for 1 hour. Then, using 5 L of ion-exchanged water, washed and filtered, dried in air at 120 ° C. for 12 hours, and fired at 400 ° C. for 1 hour. The resulting fired product was crushed, and 1.0 mm and 1.4 mm meshes were obtained. The product was sieved with a sieve having a desulfurizing agent 3.

Example 4 Ni, Mo, Ca coprecipitation (1) (first method)
After warming deionized water 1L to 80 ° C., a NiSO ₄ · 6H ₂ O 126.5g, was obtained _{Ca (NO 3) 2 · 4H} 2 O and 5.6g added preparation A. Separately prepared ion-exchanged water 1L colloidal silica Snowtex XS (Nissan Chemical Industries, Ltd.) 33.9 g, sodium carbonate _{59.4g, (NH 4) 6 Mo} 7 O 24 · 5H 2 O was added 3.9 g, Heated to 80 ° C. to obtain Preparation B. While maintaining the preparation liquid A and the preparation liquid B at 80 ° C., the liquid B was instantaneously added to the liquid A and stirred for 1 hour. Then, using 5 L of ion-exchanged water, washed and filtered, dried in air at 120 ° C. for 12 hours, and fired at 400 ° C. for 1 hour. The resulting fired product was crushed, and 1.0 mm and 1.4 mm meshes were obtained. The resultant was sieved with a sieve having the above to obtain a desulfurizing agent 4.

Comparative Example 1 Ni and Mo coprecipitation (1) (first method)
1.24 g of boehmite AP-3 (manufactured by Catalyst Kasei Kogyo Co., Ltd.) was added to 1 L of ion-exchanged water, heated to 80 ° C., and then 126.5 g of NiSO ₄ .6H ₂ O was added to obtain Preparation Liquid A. Separately prepared ion-exchanged water 1L colloidal silica Snowtex XS (Nissan Chemical Industries, Ltd.) 33.9 g, sodium carbonate _{59.4g, (NH 4) 6 Mo} 7 O 24 · 5H 2 O was added 3.9 g, Heated to 80 ° C. to obtain Preparation B. While maintaining the preparation liquid A and the preparation liquid B at 80 ° C., the liquid B was instantaneously added to the liquid A and stirred for 1 hour. Then, using 5 L of ion-exchanged water, washed and filtered, dried in air at 120 ° C. for 12 hours, and fired at 400 ° C. for 1 hour. The resulting fired product was crushed, and 1.0 mm and 1.4 mm meshes were obtained. Sieving was carried out with a sieve having the above to obtain a desulfurizing agent 5.

Comparative Example 2; Ni, Mo, Ca coprecipitation (1) (first method)
1.24 g of boehmite AP-3 (manufactured by Catalyst Kasei Kogyo Co., Ltd.) was added to 1 L of ion exchange water and heated to 80 ° C., then 126.5 g of NiSO ₄ .6H ₂ O, Ca (NO ₃ ) ₂ .4H ₂ O 9.0 g was added to obtain Preparation A. Separately prepared ion-exchanged water 1L colloidal silica Snowtex XS (Nissan Chemical Industries, Ltd.) 33.9 g, sodium carbonate _{59.4g, (NH 4) 6 Mo} 7 O 24 · 5H 2 O was added 3.9 g, Heated to 80 ° C. to obtain Preparation B. While maintaining the preparation liquid A and the preparation liquid B at 80 ° C., the liquid B was instantaneously added to the liquid A and stirred for 1 hour. Then, using 5 L of ion-exchanged water, washed and filtered, dried in air at 120 ° C. for 12 hours, and fired at 400 ° C. for 1 hour. The resulting fired product was crushed, and 1.0 mm and 1.4 mm meshes were obtained. The resultant was sieved with a sieve having the above to obtain a desulfurizing agent 6.

<X-Ray Diffraction Analysis of Desulfurization Agents of Examples 1-4 and Comparative Examples 1-2>
Each of the desulfurization agents 1 to 6 was filled in a reaction tube, reduced at 400 ° C. for 3 hours in a H ₂ stream, and then subjected to X-ray diffraction measurement for a sample subjected to stabilization treatment with 1% oxygen. As a result, it was confirmed that any desulfurization agent had a diffraction peak of metallic Ni at 2θ = 51.5 °.

<The kerosene desulfurization test of the desulfurization agent of Examples 1-4 and Comparative Examples 1-2>
A desulfurization test of kerosene was performed using desulfurization agents 1 to 6, and the desulfurization performance was compared. In this desulfurization test, initial distillation temperature 154 ° C., 10% distillation temperature 171 ° C., 30% distillation temperature 186 ° C., 50% distillation temperature 201 ° C., 70% distillation temperature 224 ° C., 90% distillation temperature 253 ° C. JIS No. 1 kerosene having a distillation property of 277 ° C. at the end point and containing 8.8 ppm by mass of sulfur was used. Table 1 shows the properties of the kerosene used.
First, prior to the desulfurization reaction, the desulfurizing agent was reduced and activated. That is, 11.6 ml of a desulfurizing agent was filled in a SUS reaction tube having an inner diameter of 16 mm. Then, the temperature of the reaction tube was raised to 400 ° C., and the desulfurization agent was reduced and activated by maintaining it in a hydrogen stream under normal pressure for 3 hours.
Thereafter, the JIS No. 1 kerosene was circulated through each reaction tube containing the activated desulfurizing agent at a pressure of 0.7 MPa, a temperature of 200 ° C., and a liquid space velocity of 4 hr ⁻¹ , and the product oil was supplied downstream of the reaction tube. Collected every hour. The desulfurization experiment was continued until the sulfur content in the collected product oil exceeded 50 mass ppb, and the time taken to break through 50 mass ppb was defined as the 50 mass ppb breakthrough time. The results are shown in Table 2.

<Measurement of carbon deposition amount on desulfurizing agents of Examples 1 to 4 and Comparative Examples 1 and 2>
Using the desulfurizing agents 1 to 6, the amount of carbon deposited on the desulfurizing agent after the reaction for 118 hours was measured. The results are shown in Table 2.

From the results shown in Table 2, the desulfurization agent of the present invention containing specific amounts of nickel, molybdenum, and calcium has a suppressed carbon deposition amount on the desulfurization agent as compared with the desulfurization agent of Comparative Example 1 that does not contain calcium. 50 mass ppb breakthrough time was extended and it was found to be a long-life desulfurization agent. Further, it has been found that when the calcium content increases beyond the provisions of the present invention, the specific surface area of the desulfurizing agent decreases, and the intended breakthrough time of 50 mass ppb cannot be extended.

Claims (3)

Nickel is 50 to 95% by mass in terms of oxide (NiO), molybdenum is 0.5 to 25% by mass in terms of oxide (MoO ₃ ), calcium is 0.1 to 3% by mass in terms of oxide (CaO), And a hydrocarbon desulfurization agent characterized by containing an inorganic oxide. The hydrocarbon desulfurization agent according to claim 1, wherein the inorganic oxide is at least one of SiO ₂ , Al ₂ O ₃ , and SiO ₂ —Al ₂ O ₃ . Using the desulfurizing agent according to claim 1 or 2, the sulfur content in the hydrocarbon is reduced to 50 under conditions of a reaction temperature of 0 to 400 ° C, a reaction pressure of 0.1 MPa or more, and a liquid space velocity of 0.01 to 100 hr- ^1. A hydrocarbon desulfurization method with a mass of ppb or less.