JP2591971B2 - Hydrogen production method for distributed fuel cell - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION INDUSTRIAL APPLICABILITY The present invention uses a nickel-based sorbent to remove sulfur contained in JIS No. 1 kerosene, and adds water to the kerosene thus treated to obtain a nickel-based catalyst. The present invention relates to a method for producing a hydrogen source for a distributed fuel cell by causing a reforming reaction to be carried out using the same.

Problems to be solved by conventional technologies and inventions Fuel cells have high energy conversion efficiencies and are less likely to degrade the environment. It is expected that the technology will be completed from various fields. Although various substances are used as fuels for fuel cells, it is considered that fuel cells that use hydrogen as a fuel, and among others, fuel cells that use phosphoric acid as an electrolyte, are closest to practical use.

Hydrogen used for fuel cells is mainly produced by reforming liquefied natural gas (LNG) mainly composed of methane or city gas mainly composed of it with steam because of its technical ease.
Methods for producing methanol by reforming or decomposing it have been studied. For example, if fuel cells with an output of 100 to several hundreds of kW are to be distributed and installed in various places including refuges (distributed fuel cells), fuel cells using LNG or city gas must be located in a supply area with pipes. Can only be installed, and its use is very limited locally. In the case of a large-scale disaster such as an earthquake, the possibility of stopping the gas supply due to the breakage of city gas piping is quite high. Further, the method of obtaining hydrogen by reforming or decomposing methanol has a drawback that the unit cost per hydrogen is considerably higher than LNG at present.

On the other hand, if a nationwide supply network makes it possible to use commercially available kerosene as a raw material for obtaining hydrogen for fuel cells, gas stations, lorries and tank trucks distributed around the country It can be supplied to any area by bringing it in, and even in the event of an earthquake,
If the equipment is operable, it is possible to continue power generation by using stock kerosene in the area, and it is relatively easy to resume the supply of kerosene, so such an emergency occurs. Even then, continuous operation is possible.

Kerosene also has the advantage of lower unit cost for hydrogen production and lower power generation costs than LNG.

Conventionally, in a hydrogen production plant based on the steam reforming method using petroleum as a raw material, it has been possible to use light hydrocarbons such as offgas and LNG, as well as LPG and naphtha as raw materials. It has been considered difficult to use as a raw material. The main reason is that when kerosene is used, the reforming catalyst used so far has a low decomposition rate and carbon content adheres. In addition, kerosene is more difficult to desulfurize than light hydrocarbons such as LPG or naphtha,
Therefore, stricter desulfurization is not performed, sulfur remains,
As a result, the active point of the catalyst is poisoned, and there is a disadvantage that the catalyst does not last long.

However, due to recent technological advances, nickel catalysts that have a sufficient decomposition rate even with kerosene and have low carbon content are being clarified.

However, even this catalyst is sensitive to sulfur, and sulfur as a reforming raw material is 0.5 wtppm or less, and in some cases, 0.2 wtp
Very low desulfurization is required below pm. However, it is not necessary to make the sulfur content in kerosene as high as this level for the purpose of supplying kerosene to a heater which is a general use of kerosene. JIS (K2203) No. 1 kerosene has an upper limit of 150w for sulfur
tppm, generally 10wtppm ~ 150wtppm,
At present, about 20 to 60 ppm by weight of kerosene is currently commercially available.

However, as described above, H ₂ used in a distributed fuel cell
In the case of kerosene used for the production of kerosene, it is most convenient to use JIS No. 1 kerosene in consideration of the nationwide kerosene supply system.

Therefore, in order to use JIS No. 1 kerosene for this purpose, generally 10 to 150 wtppm
Pretreatment for the desulfurization of JIS No. 1 kerosene containing sulfur must be performed to reduce the sulfur content in kerosene to 0.5 wtppm or less.

It is not impossible to directly hydrodesulfurize such a kerosene having a relatively high sulfur content to make the sulfur content 0.5 wtppm.
However, in this case, in the presence of hydrogen, 20 to 100 kg / cm ²
G, high-temperature and high-pressure conditions of 300 ° C or higher are required.

For large-scale equipment with a power generation capacity of 1000KW or more, which is expected to be installed in a relatively large factory, such severe conditions of high pressure and high temperature are not difficult considering the safety and environmental conditions that large-scale factories should have. .

However, in the case of a distributed fuel cell having only a power generation capacity of 500 KW or less as described above, the expected installation location is in the vicinity of a building or building, in a basement, or the like.
In view of environmental considerations and related laws and regulations, in particular, the High Pressure Gas Control Law, the reaction is required to be carried out at a pressure of less than 10 kg / cm ² · G.

The present inventors have previously used a Ni-based sulfur sorbent at a pressure of less than 10 kg / cm ² · G and a temperature of 150 to 250 ° C. in Japanese Patent Application No. 61-175322. , 0.5w sulfur content in refined oil
A method for desulfurization to below tppm was proposed. After that, the present inventors further studied the technology for removing the sulfur content in the kerosene fraction, and as a result, although not necessarily for a reason, proposed in Japanese Patent Application No. 61-175322 in a commercially available kerosene fraction. It has been found that some sorbents cannot exert their full capacity at the temperatures given. It was presumed that these kerosene fractions contained sulfur compounds that were clearly difficult to react with the Ni sorbent. The present inventors have studied a method for producing a raw kerosene suitable for steam reforming from kerosene from which it is difficult to remove sulfur, and found that the reaction temperature exceeded 250 ° C and 300 ° C.
It has been found that processing can be performed if the temperature is raised to a temperature of not more than ° C, and the present invention has been accomplished. However, when the temperature was raised above 300 ° C., the amount of coke deposited increased significantly, and the life was shortened.

That is, JIS No. 1 kerosene containing a sulfur content of 10 to 150 wtppm has been desulfurized to a residual sulfur content of 0.5 wtppm or less under a pressure of less than 10 kg / cm ² G and a temperature exceeding 250 ° C., and the desulfurized kerosene is nickel-based. There has been no known hydrogen production method for a distributed fuel cell in which a steam reforming reaction using a catalyst is performed to produce a hydrogen source to be supplied to the distributed fuel cell.

In addition, the present inventors reduced the sulfur content, which is relatively difficult
JIS No. 1 kerosene containing up to 150 wtppm is treated at a pressure of less than 10 kg / cm ²・ G at a temperature of more than 250 ° C and 300 ° C or less to reduce the contained sulfur to 0.5 wtppm or less, which is converted to a nickel-based catalyst. As a result of intensive studies on a method of producing a hydrogen source for a dispersed fuel cell by steam reforming, the present invention has been achieved.

Conventionally, as a method for removing sulfur compounds in petroleums, particularly light hydrocarbons such as LNG, LPG and naphtha, according to the Japan Petroleum Institute, Vol. 2, No. 2, p.
A method in which sulfur in hydrocarbons is converted to hydrogen sulfide by treating at high temperature and high pressure using a catalyst such as nickel-molybdenum or nickel-tungsten, or alkali treatment, sorbitizer treatment, oxidation sweetening treatment and acid treatment Etc. were known. In addition, zinc oxide,
There is known a method for removing a sulfur compound in a light hydrocarbon oil using a metal oxide such as copper oxide, manganese oxide, and iron oxide.

When these conventional techniques are applied as a desulfurization method for JIS No. 1 kerosene containing 10 to 150 wtppm of sulfur in a fuel cell hydrogen production system aimed at by the present invention, the most common hydrodesulfurization method is as follows. It cannot be used because a high pressure of 10 kg / cm ² · G or more is required as reaction conditions. In addition, the types of sulfur compounds to be removed are limited in the alkali treatment, the sorbitizer treatment, and the oxidation sweetening treatment, and thiophenes essentially contained in kerosene are not removed at all, or even if they are purified, the ratio is small. It is difficult to reduce the sulfur content in kerosene to 0.5 wtppm or less, so it cannot be adopted. Furthermore, the processing steps are long, and the operation is complicated, which is not suitable for the purpose of the present invention.

Next, the method using metal oxides such as zinc oxide, copper oxide, manganese oxide and iron oxide is considered preferable from the viewpoint of operability if the sulfur content in kerosene is sufficiently removed. Et al. Examined the possibility of these oxides by experiments. However, when these four types of metal oxides were used, although a certain degree of desulfurization activity was obtained, kerosene having a target sulfur content of 0.5 wtppm or less in the present invention was not obtained. That is, it has become clear that metal oxides generally known for hydrocarbons lighter than naphtha and for removing sulfur compounds in those hydrocarbons do not directly apply to kerosene.

Therefore, the present inventors have found that various metal oxides other than the above-described four metal oxides or metals reduced therefrom contain 10 to 150 wtppm of a sulfur content either directly or by being supported on various carriers. The inventors of the present invention have studied the desulfurization method of JIS No. 1 kerosene.

The present invention relates to JIS No. 1 kerosene having a sulfur content of 10 to 150 wtppm, in the absence of hydrogen per mole of kerosene, or in the presence of 0.2 mol or less of hydrogen, at a pressure of 10 kg / cm ² · G at atmospheric pressure or higher. A reaction filled with a nickel-based sorbent with a surface area of 50 m ² / g or more, in which nickel is supported on a support in an amount of more than 40 wt% under a pressure of less than 250 ° C. and a temperature of more than 250 ° C. Through a reactor to reduce the residual sulfur content in kerosene to 0.5 wtppm or less, add the required amount of water to all fluids leaving the reactor, and fill with a reforming catalyst having a nickel content of 5 wt% or more. This is a hydrogen production method for a distributed fuel cell in which the entire amount is directly loaded into a reactor to cause a reforming reaction to produce a hydrogen source to be supplied to the distributed fuel cell.

Originally, a nickel-based sulfur sorbent removes traces of sulfur remaining during hydroprocessing in the pretreatment stage of raw materials for naphtha reforming equipment that produces gasoline and aromatic hydrocarbons. A known method is to remove a small amount of sulfur from a raw material for the nuclear hydrogenation of aromatic hydrogen using a nickel catalyst.

However, in a hydrogen production system that reforms light hydrocarbons such as LNG, LPG or naphtha with steam, a method for removing sulfur from the raw material is to decompose the sulfur compounds in the raw material by hydrorefining and convert the generated hydrogen sulfide. A method of treating with a sorbent mainly composed of zinc oxide is generally performed, and a method of using metallic nickel, nickel oxide, or a composite thereof as a sorbent is not performed. Moreover, the sulfur content in kerosene, which is a heavy hydrocarbon oil, is almost completely removed using only a nickel-based sorbent without hydrorefining treatment. The technology for producing hydrogen in a reforming reactor has not been known so far.

In U.S. Pat. Alternatively, a method of passing through a reaction tower filled with cobalt or the like is disclosed. However, this method only shows the pretreatment of a raw material for producing gasoline or aromatic hydrocarbons by a naphtha reforming reaction using a platinum-based catalyst. No mention is made of the desulfurization process.

British Patent No. 1,232,393 shows that a nickel-based sorbent can be used as a method for removing 1 to 50 wtppm of sulfur in an aromatics-containing fraction having a boiling point range of 50 to 150 ° C.
However, this method treats No. 1 kerosene to remove residual sulfur.
There is no mention of a method to reduce the amount of kerosene to 0.5wtppm or less and use this treated kerosene as a raw material for hydrogen production, and desulfurize No. 1 kerosene using a nickel-based sorbent so that it is suitable for kerosene as a raw material for hydrogen production. Different from the method of the present invention.

The raw material used in the present invention contains 10 to 150 wtppm of sulfur.
JIS No. 1 kerosene.

Usually, this JIS No. 1 kerosene is obtained by desulfurizing a predetermined fraction (crude kerosene) obtained by distilling crude oil under normal pressure, or desulfurizing a crude kerosene by mixing various cracking kerosene fractions, or After desulfurization of crude kerosene, it is obtained by mixing various cracked kerosene fractions.

In recent years, demand for heavy oil has decreased, and demand for white oil has tended to increase.Various types of heavy oil cracking equipment have been constructed, and light cracked oil produced from them has been mixed with the equivalent fraction of the straight-run system. The tendency to use is growing. Kerosene containing these cracked kerosene fractions tended to require a higher treatment temperature with nickel-based sorbents. This is probably due to the fact that the sulfur compounds contained in these cracked kerosene fractions are more stable than those of the straight-run type, and the reaction rate becomes higher at higher temperatures when Ni-based sorbents are used. .

Normally, crude kerosene mixed with crude kerosene or cracked kerosene fractions has a high sulfur content and does not become JIS No. 1 kerosene as it is,
There is a need to reduce sulfur content. The desulfurization method is preferably carried out by a hydrorefining method generally used industrially. In this case, a mixture of a transition metal such as nickel, cobalt, molybdenum or tungsten in an appropriate ratio is used as a catalyst. What is supported on a carrier mainly composed of alumina in the form of oxide or sulfide is used. The reaction conditions are reaction temperature 250-400 ° C, pressure
Conditions such as 20 to 100 kg / cm ² · G, a hydrogen / oil molar ratio of 2 to 10, and a liquid hourly space velocity (LHSV) of 1 to 5 are used. Kerosene treated under such hydrorefining conditions usually has a sulfur content of 10-15.
0 wtppm, more generally 20 to 60 wtppm.

This refined kerosene is shipped from a refinery as No. 1 kerosene specified in JIS, can be easily obtained from a gas station or a kerosene dealer, and can be used in the present invention.

In the present invention, this kerosene is treated under predetermined conditions with a nickel-based sorbent described in detail below.

The nickel-based sorbent of the present invention has a total nickel content of 40 wt.
%, Preferably 52 to 70% by weight. When a sorbent with a nickel content of 40 wt% or less is used, if kerosene containing 10 to 150 wtppm of sulfur is passed under specified conditions, the sulfur content at the outlet at the beginning of oil passing is desulfurized to 0.5 wtppm or less. In this case, it is clear that the cause is not clear, but there is a defect that the outlet sulfur concentration exceeds 0.5 wtppm in a time very short than the time estimated from the nickel amount, which is not practical. On the other hand, the nickel content of the present invention is 40
When a nickel-based sorbent exceeding wt% is used, the usable time becomes close to the time expected from the nickel content under the same conditions, and the nickel contained in the sorbent removes sulfur from kerosene. It became clear that it was used effectively.

Since the distributed fuel cell, which is the object of the present invention, needs to be operated without maintenance for a long time without any human intervention, the desulfurization method of kerosene as a raw material requires a short-term exchange of a sulfur sorbent. The method of the present invention is not suitable.

The nickel-based sorbent of the present invention preferably contains reduced nickel. If the sorbent contains reduced nickel, the object of the present invention is met even if nickel oxide or a compound of nickel and another substance coexists. Further, those containing a small amount of a metal component such as copper, chromium, zirconium, magnesium or the like can also be used. A carrier is usually used for the nickel sorbent. As the carrier, silica, alumina, silica-alumina, titania, zirconia, zinc oxide, clay, clays, diatomaceous earth, and other refractory inorganic oxides can be used. preferable. The surface area of the sorbent is at least 50 m ² / g, preferably at least 100 m ² / g.

Various methods are used for preparing the nickel-based sorbent. For example, the following method is preferably used.

1) A method in which an alkaline aqueous solution such as sodium carbonate is added to an aqueous solution of a nickel salt such as nickel nitrate or nickel sulfate to precipitate on a carrier in the form of basic nickel carbonate, washed and dried, and then thermally decomposed into nickel oxide. . 2) A method in which a carrier is impregnated with an easily decomposable aqueous solution of nickel salt such as nickel nitrate, which is dried and thermally decomposed into nickel oxide. However, the method for preparing the nickel-based sorbent used in the present invention need not be limited to these methods, and a nickel-based sorbent having a surface area of 50 m ² / g or more in which nickel is supported on a carrier in an amount exceeding 40 wt% as a metal component. Once the sorbent is obtained,
Those prepared by other production methods can also exert their effects.

These nickel-based sorbents may be subjected to reduction treatment with hydrogen at a temperature of 150 to 400 ° C. before use, and this operation is performed even after filling in a sorption tower for desulfurizing kerosene. Alternatively, it may be performed using another apparatus before filling. In this case, in order to avoid danger such as ignition, a part of the metal nickel may be oxidized or carbon dioxide may be adsorbed to stabilize the surface. Further, after the nickel-based sulfur sorbent subjected to these treatments is filled in the sorption tower, it may be passed through the raw kerosene as it is, or the nickel oxide layer on the surface may be preferably reduced using hydrogen. Further, the sorbent having adsorbed carbon dioxide gas is preferably used after removing carbon dioxide gas with an inert gas such as hydrogen or nitrogen. The shape of the sorbent may be any shape such as a tablet, an extruded product, a spherical product or a crushed product.

JIS1 No. kerosene containing undecomposable sulfur compounds upward through the sorption column in a liquid phase, or pass with downward flow, pressure atmospheric pressure or higher 10 Kg / cm less than ² · G, temperature 250 to 300 ° C., the LHSV10 below Processed on condition. In this case, it is preferable that the kerosene is essentially kept in a liquid phase, and therefore, when the properties of the kerosene to be treated are light or when a relatively high temperature is required to obtain kerosene having a sulfur content of 0.5 wtppm or less. Need to increase pressure. Although the sulfur sorbent of the present invention can obtain a satisfactory performance even if only kerosene is passed, a method of coexisting 0.2 mol or less of hydrogen per 1 mol of kerosene under sorbent conditions is also used. sell. However, a method that does not use hydrogen is more preferable because there is no device having a space such as a gas-liquid separator and the device is simple.

Kerosene treated under such methods and conditions has a sulfur content reduced to 0.5 wtppm or less, and has properties suitable for use as a raw material kerosene for a steam reformer using a nickel catalyst in the next stage. .

The kerosene treated by the method of the present invention is then sent to a steam reformer filled with a nickel catalyst. The nickel catalyst used for the steam reforming of kerosene contains nickel in an amount of 5 wt% or more, for example, 5 to 50 wt%, preferably 10 to 35 wt%. Here, the nickel catalyst used here is a catalyst containing nickel as a metal, oxide or other compound, and generally exists as nickel in a reduced state under reforming reaction conditions. Is used. As the carrier, alumina, magnesia, silica, calcia, magnesia-alumina spinel, each alone or in a mixture, is used.
A catalyst to which 5 wt% or less of potassium oxide is added is used. The reaction conditions are reaction temperature 500 ~ 1,000 ℃, reaction pressure 3Kg / cm
Less than ² · G or more 10Kg / cm ² · G, steam / carbon (molar ratio) is 2~6, LHSV0.2~4 is preferably used.

Sulfur compounds contained in raw hydrocarbons are known as active poisons for nickel catalysts for steam reforming, and hydrogen sulfide generated when sulfur compounds come into contact with nickel catalysts is nickel stoichiometric. To nickel sulfide and loses its activity. Therefore, the sulfur content in the raw material to be subjected to the reforming reaction is desirably as small as possible. However, from an economic viewpoint, the sulfur content in the raw material is industrially 0.5 wtppm or less, more preferably 0.2 wtppm or less. If a steam reforming reaction is carried out with a nickel catalyst using a raw material kerosene with a sulfur content exceeding 0.5 wtppm, the catalyst will be poisoned from the vicinity of the reaction tower inlet, and undecomposed hydrocarbons will quickly flow from the reaction tower outlet. Is detected or a hot spot is generated at the inlet of the reaction tube, and a phenomenon in which ΔP of the reaction tube increases due to coking occurs, and the operation must be stopped in a short period of time to exchange or regenerate the catalyst.

EXAMPLES Next, the method of the present invention will be specifically described using examples.

Example 1 (1) Preparation of nickel-based sorbent Water was added to 65 g of nickel nitrate to make the total volume 250 ml. 8 g of diatomaceous earth is added thereto, and the mixture is stirred at 80 ° C. in a hot water bath. Separately, 42 g of sodium carbonate was dissolved in water to make a total volume of 250 ml.
Add slowly while maintaining at 80 ° C to form a precipitate. After the addition, stirring is continued for 1 hour to ripen the precipitate. Thereafter, the precipitate is filtered to obtain a precipitate cake. The cake is washed several times with warm water to remove alkali and dried.
After the dried cake is crushed, it is baked at 350 ° C. for 1 hour in the air. The calcined powder is placed in a quartz tube and reduced at 380 ° C. for 30 minutes in hydrogen. After reduction, the mixture is cooled in nitrogen, and then carbon dioxide gas is introduced to stabilize nickel. 5 wt% of graphite is added to the powder taken out and molded into a tablet of 3 mmφ × 3 mm. This molded product was crushed into a size of about 1 mm, packed in a sorption tower, and heated at 200 ° C. for 30 minutes while heating in hydrogen while taking care not to generate heat. The nickel content in the sorbent was 65% by weight and the surface area was 150 m ² / g.

(2) JIS No. 1 kerosene A commercially available JIS No. 1 kerosene having the following properties was used as a raw material.

Sulfur content 62wtppm, specific gravity (15/4 ℃) 0.799, boiling point range 165
At ~ 269 ° C, aromatic content 253vol%, smoke point 23mm.

(3) Desulfurization experiment Using the nickel-based sorbent prepared in (1), the kerosene of (2) as a raw material, pressure 9 kg / cm ² · G, temperature 275 ° C, LHSV 0.
Processed under the conditions of 2. A stainless tube having an inner diameter of 20 mmφ was used for the sorption tower, and a sorbent crushed to about 1 mm was filled into the sorption tower and filled with 40 cm ³ . The sulfur content of the kerosene at the outlet was almost below the measurement limit from 5,000 hours to the beginning of oil passage, but then gradually increased to 0.2wtppm or more after about 5,500 hours. .

(4) Steam reforming experiment Using JIS No. 1 kerosene desulfurized by the method of (3) as a raw material
Reaction pressure of 9 kg / cm ² · using a reaction tube filled with a heat-resistant steel tube with an inner diameter of 15 mm filled with a crushed product of about 1 mm of a steam reforming catalyst consisting of 34 wt% of O, 12 wt% of Al ₂ O _3, and 54 wt% of MgO. G, Reaction Temperature A steam reforming reaction was performed under the conditions of a reaction tube inlet 500 ° C., outlet 850 ° C., LHSV1.5, and H ₂ O / C3.5 (mol / mol). After 500 hours from the start of the reaction, there is almost no change in the temperature distribution of the reaction tube even after 500 hours, the gas composition at the outlet is almost close to the thermodynamic equilibrium value, and if the sulfur content is reduced to 0.5 wtppm or less, even kerosene can be sufficiently steamed. It has been found that reforming produces hydrogen.

Example 2 (1) Production of raw kerosene A kerosene fraction (sulfur content: 2500 wtppm) was collected from an Arabic crude oil by a normal pressure distillation apparatus, and 10% of coker kerosene was mixed with this. This was subjected to a hydrotreating apparatus packed with a cobalt (2.5 wt% as CoO) -molybdenum (12.5 wt% as MoO ₃ ) alumina catalyst, at a pressure of 50 kg / cm ² · G and a temperature of 320.
℃, LHSV2, hydrogen / oil ratio 300Nl / l, sulfur content 38wt
ppm, specific gravity 0.788, boiling point range 160-260 ° C, aromatic content 18vol
%, A purified kerosene having a smoke point of 25 mm was obtained. This was treated with a sulfur sorbent prepared in the following manner.

(2) Sulfur sorbent A commercially available Ni-based sulfur sorbent for naphtha was used. The sorbent had a Ni content of 47% and a surface area of 150 m ² / g.

(3) Desulfurization experiment While the sorbent was filled with this sorbent while avoiding air contact, it was subjected to the next desulfurization of kerosene.

Kerosene sorption conditions are pressure 7Kg / cm ² · G, temperature 290 ° C, LH
SV 0.2, hydrogen / oil 0.02 mol / mol. From the beginning of oiling
For 8,500 hours, only 0.1 wtppm or less of sulfur was detected from the treated kerosene, and then increased gradually after about 12,000 hours.
The value became 0.5 wtppm.

(4) Steam reforming experiment Using kerosene desulfurized by the method of (3) as raw material, NiO
The reaction was carried out under the same conditions and conditions as in Example 1 using a steam reforming catalyst composed of 2 wt%, 26 wt% of Al ₂ O ₃ and 11 wt% of MgO crushed to about 1 mm. 500 hours after the start of the reaction, when the maximum temperature of the reaction tube slightly shifted to the outlet of the reaction tube, the outlet gas composition was close to the thermodynamic equilibrium value at that temperature, and the sulfur content was reduced to 0.5 wtppm or less. It is clear that if reduced, hydrogen can be produced from kerosene without any problems.

Comparative Example 1 The commercially available No. 1 kerosene used in Example 1 was used as a raw material and treated under the same conditions as in Example 1 using a commercially available nickel-containing diatomaceous earth catalyst of 3.5 wt% nickel as a sorbent for sulfur. From the initial stage of oil passing, the outlet sulfur content was 0.5 wtppm or more, and it was found that kerosene with 0.5 wtppm or less could not be obtained with this sorbent. The treatment was continued for a while to obtain kerosene having an average sulfur content of 10 wtppm. Then use the obtained kerosene as raw material (average sulfur content 10wtppm)
And a steam reforming reaction was carried out under the same conditions using the same catalyst as in Example 1. As a result, the hydrogen gas content was obtained smoothly at the beginning of the reaction, but after about 20 hours from the reaction, the heat absorbing part of the reaction tube gradually moved toward the outlet of the reaction tube, and the portion showing the highest temperature was also lowered. After 50 hours, unreacted hydrocarbons were detected in the outlet gas.

Effects of the Invention As is clear from the above Examples and Comparative Examples, by treating JIS No. 1 kerosene with the nickel-based sulfur sorbent of the present invention, the kerosene in kerosene under a pressure of less than 10 kg / cm ² Sulfur is reduced to an amount suitable for steam reforming reactions using nickel-based catalysts, enabling long-term stable production of hydrogen-based fuel gas suitable for operation of distributed fuel cell systems with a power generation capacity of 100 to 500 kW It became clear that.

According to the method of the present invention, an inexpensive distributed power source using kerosene and having no concern about the supply stability of the raw material can be used.

Claims (1)

(57) [Claims] Claims 1. A JIS No. 1 kerosene containing 10 to 150 wtppm of a sulfur content is added to 1 kg of kerosene in the absence of hydrogen or in the presence of 0.2 mol or less of hydrogen at 10 kg / cm ^2. Under a pressure of less than G and a temperature of more than 250 ° C. and less than 300 ° C., a nickel-based sorbent having a surface area of 50 m ² / g or more in which nickel was supported on the support in an amount of more than 40 wt% as a metal component was filled. Steam reforming which is passed through a reactor to reduce the residual sulfur content in kerosene to 0.5 wtppm or less, and the required amount of water is added to all fluids leaving the reactor, and a reforming catalyst having a nickel content of 5 wt% or more is filled. A hydrogen production method for a distributed fuel cell, in which the whole amount is directly charged into a reactor to cause a reforming reaction, and a hydrogen source to be supplied to the distributed fuel cell is produced.