JP2961585B2 - Method for deep desulfurization of medium and light oil - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for deep desulfurization of medium and light oils such as naphtha and kerosene, and more particularly to a pretreatment step for generating hydrogen by steam reforming of these medium and light oils. The present invention relates to a method for deep desulfurization of medium and light oil as a raw material.

[0002]

2. Description of the Related Art When hydrogen used in industrial or fuel cell systems is obtained by steam reforming of medium and light oils such as naphtha and kerosene, these medium and light oils are protected in order to protect the steam reforming catalyst. 0.5wtpp in advance for the total sulfur content in the feedstock
m or less, preferably to 0.2 wtppm or less. Conventionally, a typical desulfurization method performed prior to the steam reforming of the above-mentioned raw material is a Ni-Mo-based or Co-
About 300 to 400 in a hydrogen stream in the presence of a Mo-based catalyst
° C., after hydrogenolysis of organic sulfur in the feed at a pressure of about 15~40kg / cm ² G, hydrodesulfurization process for removing by adsorbing generated H ₂ S in ZnO [hereinafter desulfurization (1 ). In addition, another method is known in which kerosene is used as a raw material and adsorptive desulfurization is carried out using a catalyst supporting a large amount of Ni and having a specific surface area of 50 m ² / g or more [Japanese Patent Application Laid-Open No. Hei 1-1]
No. 88405, hereinafter referred to as desulfurization method (2)].

[0003]

However, in order to sufficiently reduce the sulfur content in the raw material in the desulfurization method (1), it is essential to use hydrogen gas having a high purity of about 95% or more. . On the other hand, in an industrial hydrogen production apparatus, after the steam reforming step, CO and CO ₂ contained in the product gas are removed to increase the hydrogen purity.
A decarboxylation step and the like are provided to enable the hydrogen purity to be maintained at about 95% or more. By circulating a part of the high-purity hydrogen gas as the target and supplying it to the raw material desulfurization step, desulfurization to a sulfur concentration of about 0.5 wtppm or less is achieved.

In the above-mentioned fuel cell system and the like, in order to obtain hydrogen from a medium or light oil such as naphtha or kerosene as a raw material, the size of the apparatus is reduced, and in terms of safety measures, it is efficiently obtained under low pressure conditions. Is required to be In order to respond to this demand, in order to reduce the size of the apparatus, the above-described decarboxylation step is not required, and the gas after steam reforming is used at a pressure of 10 kg / cm ² G or less and instead of high-purity hydrogen. It is conceivable to convert the contained CO into CO ₂ and desulfurize the sulfur content of the raw material to about 0.5 wtppm or less using the CO ₂ -containing hydrogen gas. However, in the desulfurization method (1) described above, if CO ₂ is contained in the hydrogen gas used, the desulfurization efficiency is reduced, and it has been difficult to reduce the sulfur content in the feedstock oil to a predetermined amount.

The catalyst used in the desulfurization method (2) is N
Due to the large amount of i supported, the adsorption desulfurization using this catalyst shortens the life of the catalyst, further causes a methanation reaction, increases the methane concentration in the exhaust gas, and makes it difficult to control the temperature due to heat generation. was there.

Accordingly, the present invention provides a method for producing C
Depth desulfurization method that can reduce the sulfur concentration of medium and light oils such as naphtha and kerosene to 0.5 wtppm or less without using methanation reaction and reducing catalyst life even when using hydrogen gas containing O ₂ The purpose is to provide.

[0007]

Means for Solving the Problems Accordingly, the present inventors have:
As a result of intensive studies for achieving the above object, a predetermined amount of nickel or the use of the nickel oxide was supported on zinc oxide catalyst, an organic sulfur water in the raw material be used CO ₂ containing hydrogen gas at a low pressure condition Both the decomposition and the adsorption and removal of H ₂ S generated by the reaction can be performed extremely efficiently, and furthermore, methanation can be prevented by setting the adsorption amount of nitric oxide at 40 ° C. of the catalyst to a specific range,
In addition, they have found that the life of the catalyst is extended, and have completed the present invention.

That is, the present invention relates to a method for desulfurizing a medium-to-light oil, comprising: supporting nickel or nickel oxide on zinc oxide in an amount of less than 40% by weight in terms of metal in the presence of a hydrogen-containing gas; Using a catalyst having a capacity of adsorbing nitric oxide of 0.02 cc / m ² or more per unit area, a temperature of 180 to 440 ° C. and an LHSV of 0.1
The present invention relates to a method for deep desulfurization of medium and light oils, wherein desulfurization is performed under the conditions of ２2 h ⁻¹ and a pressure of 30 kg / cm ² G or less.

Hereinafter, the present invention will be described in detail. The catalyst used in the present invention is nickel or nickel oxide (hereinafter, referred to as nickel oxide or nickel oxide).
40% by weight in metal conversion)
It is supported on zinc oxide, and has a nitrogen monoxide adsorption capacity (hereinafter simply referred to as NO adsorption capacity) of 0.02 cc / m ² or more per unit area of the catalyst area at 40 ° C. The amount of Ni supported on ZnO is 1
The amount is not particularly limited as long as it is not less than 40% by weight, but is preferably less than 40% by weight, particularly preferably 2 to 30% by weight. 1% by weight
If it is less than 30, the desulfurization effect of Ni is not sufficient, and if it exceeds 40% by weight, the desulfurization effect is saturated, a methanation reaction occurs, heat is generated, and it becomes difficult to control the reaction temperature.

When the NO adsorption capacity of the catalyst is less than 0.02 cc / m ² , the desulfurization activity is low, and it is difficult to obtain a target sulfur content. The NO adsorbing ability of the catalyst is considered to indicate the dispersibility of the active metal on the carrier. In the present invention, however, it has been found that there is a correlation between the desulfurizing activity of the active metal and the NO adsorbing ability. . Therefore, since the desulfurization ability of the active metal is large when the NO adsorption amount is large, it is preferable to carry out the reaction under the condition that the active metal used exhibits the NO adsorption ability to the maximum. Conditions under which the active metal exhibits the maximum NO adsorption amount are as follows:
Both the carrier and the reaction temperature are related, and in the present invention using zinc oxide as the carrier, the maximum NO adsorption ability is obtained in a high temperature range of about 300 ° C. or higher.

Here, the NO adsorption amount is determined by increasing the catalyst carrying Ni on ZnO to the operating temperature range of the catalyst, and then reducing the catalyst in a hydrogen stream for about 1 to 3 hours.
After the temperature is lowered to ° C., a certain amount of NO is released in a helium stream, NO is adsorbed on the catalyst until equilibrium is reached, and measurement can be made from the difference in NO amount before and after adsorption.

In the case of the catalyst used in the present invention, its ratio table
The area is not particularly limited, but about 2 m ^Two/ G or more specific surface
A sufficiently high reaction rate can be obtained with the product. Meanwhile, the ratio table
If the area is too large, the
The amount of medium charged is reduced and H per unit catalyst bed volume is reduced._TwoS adsorption
The catalyst life may be reduced by reducing the amount.
You. Therefore, the preferred specific surface area of the catalyst is about 2 to 150 m
^Two/ G, more preferably about 3 to 110 m^Two/ G
You.

The zinc oxide used as a carrier in the present invention may be an inorganic zinc salt such as zinc borate, basic zinc carbonate, zinc nitrate or the like, or an organic zinc such as zinc benzoate, zinc lactate, zinc citrate, zinc acetate, etc. Can be produced by thermal decomposition or by calcining metallic zinc in air.
Examples of the salt of the Ni source include various salts such as nitrates, acetates, and chlorides.

Further, the catalyst of the present invention contains H
Iron oxide other than zinc oxide having _{2 S} adsorption capacity, may contain metal oxides such as copper oxide. Further, besides nickel and nickel oxide as active metals, magnesium, calcium, barium, aluminum, titanium, zirconium, vanadium, niobium, chromium, molybdenum, tungsten, manganese, copper, cobalt, other metal components and composites thereof May be included.

As a method for supporting Ni on ZnO, known methods such as an impregnation method and a coprecipitation method can be used.
To give a specific example, Zn can be obtained by the following method.
O can carry Ni.

[0016]

In the impregnation method, first, a predetermined amount of zinc oxide is weighed, and water is gradually dropped into the zinc oxide while stirring, thereby absorbing water into the zinc oxide. This water absorption is preferably performed until the inside of the zinc oxide is saturated, and the necessary amount of Ni is calculated from the saturated water absorption and the known zinc oxide. Next, an aqueous solution of the above-mentioned Ni salt adjusted to an appropriate concentration based on the amount of Ni is gradually dropped while stirring with a predetermined amount of zinc oxide weighed in the same manner as in the case of water, and saturated with water. Sintering. In the coprecipitation method, an alkaline aqueous solution is added to a mixture of an aqueous solution of zinc acetate and nitrate and an aqueous solution of Ni nitrate and acetate to form a precipitate. The precipitate is filtered, washed, dried, and dried. What is necessary is just to bake. In the above-mentioned impregnation method, when it is desired to increase the amount of supported Ni, the above-described impregnation operation may be repeated.

The above-described catalyst in which Ni is supported on zinc oxide is used in the present invention in the presence of hydrogen. However, it is preferable that the catalyst be reduced in advance in order to exhibit more activity.

The raw material which can be used in the desulfurization method in the present invention is a medium or light oil such as naphtha or kerosene containing about 1 to 150 ppm by weight of sulfur.

Further, in the desulfurization method of the present invention, the gas at the outlet of the steam reforming furnace or the gas that has undergone the subsequent CO conversion step, more specifically, the gas containing CO _{2 and} having a hydrogen purity of about 75% However, it can be used as a circulating gas in the raw material desulfurization step, and by reacting under predetermined conditions, the sulfur content in the raw material can be reduced to about 0.5 wtppm or less, and if necessary, to about 0.2 wtppm or less. Can be desulfurized.

In the present invention, the above-mentioned catalyst is packed in a fixed bed reactor, and the temperature is 180 to 440 ° C., preferably about 280 to 440 ° C., and the LHSV is about 0.1 to 2 h ⁻¹ , preferably about 0.2 ~ 1.5 h ^-1 , pressure 30 kg / cm ² G or less,
Preferably by a 1 to 10 kg / cm ² G, also by using gas hydrogen purity containing CO ₂ at about 75%, it is possible to desulfurize the sulfur content in the raw material up to about 0.5wtppm . When the reaction temperature is less than about 180 ° C., if the LHSV is faster than about 2 h ⁻¹ , the sulfur content in the raw material cannot be reduced to about 0.5 wt ppm or less, and if the reaction temperature is higher than about 440 ° C. This is not preferred in terms of catalyst life.

[0022]

According to the present invention, a catalyst in which nickel or nickel oxide is supported on zinc oxide can be used to convert a medium or light oil to a sulfur content of about 0.1 at a specific temperature, LHSV and pressure in the presence of a hydrogen-containing gas. 5wtppm or about 0.2wt
In addition to deep desulfurization down to ppm, it acts to adsorb and remove the generated H ₂ S. Also, this depth desulfurization method
When a commercially available Ni-based catalyst is subjected to desulfurization in the presence of a CO ₂ -containing hydrogen gas, a methanation reaction occurs violently and the catalyst life is extremely short.
It is characterized by a long catalyst life.

[0023]

Next, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.

Example 1 (Preparation of catalyst to be used) A catalyst supporting 9.2% by weight of nickel oxide with respect to zinc oxide was prepared. The preparation method followed the following procedure. Water was slowly added dropwise to a predetermined amount of zinc oxide using a burette with stirring, and the saturated water content of zinc oxide was measured in advance to be 0.33 ml / g-zinc oxide. Based on this value, Ni (NO ₃ ) ₂ .6H ₂ O
Was dissolved in 10 ml of water to prepare a nickel-containing aqueous solution, and the same operation as described above was performed to impregnate a predetermined amount of zinc oxide with the nickel-containing aqueous solution. 120 ° C after impregnation
For 12 hours, baking at 200 ° C., 300 ° C., and 400 ° C. for 1 hour and 510 ° C. for 14 hours, respectively, to complete the first loading. Next, the zinc oxide that has been subjected to the first nickel loading operation is subjected to a second loading by the same operation as described above, and finally, as nickel oxide, the zinc oxide is subjected to 9.2.
A catalyst supporting 2 wt% was obtained.

Next, the NO adsorption amount of the catalyst obtained above was measured according to the following procedure. The temperature of the catalyst in which nickel oxide was supported on zinc oxide was raised to 390 ° C. in a helium stream for 30 minutes, helium was replaced with hydrogen while maintaining this temperature, and the catalyst was reduced for 120 minutes. Thereafter, the hydrogen was replaced with helium again, the temperature was lowered to 40 ° C. in 40 minutes, a certain amount of NO was allowed to flow out at this temperature at atmospheric pressure, and NO was repeatedly adsorbed until equilibrium was reached. At this time, the unadsorbed NO
The amount is measured with a gas chromatograph equipped with a TCD detector,
The NO adsorption amount per unit weight of the catalyst was calculated from the NO amount before and after the adsorption. In addition, the specific surface area of the catalyst was measured with a BET measuring instrument to obtain 3 m ² / g.

Then, the amount of adsorbed NO per unit surface area of the catalyst was calculated from (NO adsorption amount per unit weight of catalyst) / (specific surface area of catalyst). As a result, the NO adsorption amount of the catalyst was 0.099 cc / m ² .

(Desulfurization Reaction 1) A catalyst supporting 9.2 wt% of nickel oxide obtained as described above with respect to zinc oxide was used as a catalyst.
ml of H ₂ and CO ₂ mixed gas (H ₂ : 75 vol%, C) using kerosene having the properties shown in Table 1 as a raw material.
O ₂ : 25 vol%), H ₂ / kerosene volume ratio = 30
0, reaction pressure 5 kg / cm ² G reaction temperature 320 ° C, LHSV
The desulfurization reaction was performed under the condition of 1.0 h ^-1 . The above reaction tube has a diameter of 9.5 mm, an inner diameter of 7.9 mm, and a length of 210 mm.
mm. As a result, the sulfur content of the desulfurized kerosene was 0.2 wtppm. Further, the concentration of methane in the produced gas was 0.7 vol% or less.

[0028]

Table 1 Density (15 ° C, g / cm ³ ) 0.7945 Sulfur content (wtppm) 49 Composition (vol%) Saturation content 82.8 Olefin content 0.4 Aromatic content 16.8 Distillation (according to JISK2254) Distillation point (° C) 155.5 10% distilling point (° C) 173.0 30% distilling point (° C) 186.5 50% distilling point (° C) 200.5 70% distilling point (° C) 217 0.0 90% distillation point (° C) 238.5 End point (° C) 263.0

(Desulfurization reaction 2) Using pure hydrogen at normal pressure instead of H ₂ and CO ₂ mixed gas, reaction temperature 380 ° C., LHSV
= 0.5 h ⁻¹ , except that (desulfurization reaction 1) was performed. As a result, the sulfur content in desulfurized kerosene was 0.11 wt.
ppm.

Example 2 10.5 g of Ni (CH ₃ COO) ₂ .4H ₂ O was used instead of the aqueous solution of Ni (NO ₃ ) ₂ .6H ₂ O used in Example 1.
Was dissolved in 10 ml of water, and the same operation as in Example 1 was carried out to obtain a catalyst supporting 9.3 wt% of nickel oxide with respect to zinc oxide. The catalyst N
The O adsorption amount was 0.08 cc / m ² . The specific surface area of the catalyst was 3.0 m ² / g. Using this catalyst, a desulfurization reaction was carried out in the same manner as in Example 1, and as a result, the total sulfur content of the desulfurized kerosene was 0.2 wtppm. Further, the concentration of methane in the produced gas was 0.7 vol% or less.

Example 3 53 g of zinc acetate and 19 g of nickel nitrate were dissolved in 600 ml of water to prepare a mixed solution of both, and an aqueous solution of ammonium carbonate in which 22 g of ammonium carbonate was dissolved in 200 ml of water and a 15% aqueous ammonia solution were added. Was added to form a precipitate of zinc carbonate and basic nickel carbonate, and the mixture was allowed to stand for about 12 hours. The precipitate was filtered, washed with water, dried at 120 ° C. for 12 hours, and charged with air at 200 ° C. for 1 hour at 300 ° C.
For 2 hours, at 400 ° C. for 1 hour, and at 510 ° C. for 16 hours to obtain a catalyst having a nickel oxide loading on zinc oxide of 15.4 wt%. The NO adsorption amount of the catalyst is 0.348 cc / m
^{Was 2} . The specific surface area of the catalyst was 4.7 m ² / g.
Using this catalyst, a desulfurization reaction was carried out in the same manner as in Example 1, and as a result, the sulfur content of the desulfurized kerosene was 0.05
It was less than wtppm. The methane concentration in the exhaust gas was 0.70 vol% or less.

Example 4 94.5 g of zinc acetate and 77.8 g of nickel nitrate were mixed with 120
Dissolve in 0 ml of water to prepare a mixed solution of both, and add this solution
Carbonic acid obtained by dissolving 22 g of ammonium carbonate in 200 ml of water
Add ammonium aqueous solution and 15% ammonia water,
Precipitate zinc carbonate and basic nickel carbonate for 12 hours
About left. The precipitate was filtered, washed with water, and dried at 120 ° C for 1 hour.
Drying for 2 hours, 1 hour at 200 ° C while introducing air,
2 hours at 300 ° C, 1 hour at 400 ° C, 16 at 510 ° C
After calcination for a period of time, the amount of nickel oxide supported on zinc oxide 29.
1% of catalyst was obtained. The amount of inorganic NO adsorbed is 0.154cc /
m ^TwoMet. The specific surface area of this catalyst is 9.0 m.^Two/ G
Met. The bulk specific gravity of the catalyst was 1.53 g / cc.
Was. Using this catalyst under the same reaction conditions as in Example 1
An evaluation test of the catalyst life was performed. Sulfur content of kerosene after desulfurization
The amount was 0.05 wtppm. Methane in exhaust gas
The concentration was 0.70 vol% or less.

Example 5 By the same operation as in Example 1, Ni (NO ₃ ) ₂ .6H ₂
Using an aqueous solution in which 6.6 g of O was dissolved in 10 ml of water, a catalyst supporting 5.3 wt% of nickel oxide with respect to zinc oxide was obtained. The NO adsorption amount of the catalyst is 0.038 cc / m
^{Was 2} . The specific surface area of the catalyst was 4 m ² / g. A desulfurization reaction was carried out in the same manner as in Example 1 using this catalyst, and as a result, the sulfur content of the desulfurized kerosene was 0.2 wtppm. The methane concentration in the exhaust gas is 0.70 vol%
It was below.

Example 6 By the same operation as in Example 1, Ni (NO ₃ ) ₂ .6H ₂
Using an aqueous solution obtained by dissolving 23.2 g of O in 10 ml of water,
As a result, a catalyst supporting 21.2% by weight of zinc oxide as nickel oxide was obtained. In this case, the impregnation operation was performed three times. The NO adsorption amount of the catalyst was 0.090 cc / m ² . After the catalyst was filled in the reaction tube, the pressure was 9.0 kg.
/ M ² G, temperature 390 ° C., pure hydrogen at a flow rate of 60 ml / min.
The mixture was allowed to flow for a time, subjected to a reduction treatment, and then subjected to a desulfurization reaction.
Desulfurization was performed under the same conditions as in Example 1, and as a result, the sulfur content after desulfurization was 0.1 wtppm or less. The methane concentration in the exhaust gas was 0.70 vol%.

[0035]

[0036]

Example 7 A catalyst life evaluation test was carried out under the same reaction conditions as in Example 1 by using the catalyst used in Example 3 and a commercially available catalyst for comparison. In addition, a commercially available catalyst is NiO 77.5wt.
%, Al ₂ O ₃ 12.0 wt%, SiO 9.0 wt%
%, CaO 1.5wt% composition, specific surface area is 165m
² / g was used. Table 2 shows the above results.

[0038]

[Table 2]

From the results shown in Table 2, the catalyst used in Example 3 had a desulfurization activity up to 0.15 wtppm of sulfur even after 1000 hours, whereas the commercially available catalyst had a sulfur content of 0.1 hours after 110 hours. The desulfurization activity is reduced to 2 wtppm, indicating that the catalyst of the present invention has about 10 times the life as compared with a commercially available catalyst. Further, it can be seen that the catalyst used in Example 3 has an extremely low CH ₄ concentration in the exhaust gas and does not cause methanation.

Example 8 Using the catalyst obtained in Example 4, an evaluation test of the catalyst life was conducted under the same reaction conditions as in Example 1. Table 3 shows the results.

[0041]

[Table 3]

Example 9 112.7 g of zinc acetate and 42.8 g of nickel nitrate were added to 10
The mixture was dissolved in 00 ml of water to prepare a mixed solution of the two. To this solution was added an aqueous solution of ammonium carbonate in which 22 g of ammonium carbonate was dissolved in 200 ml of water and 15% aqueous ammonia to precipitate zinc carbonate and basic nickel carbonate. Making 1
It was left for about 2 hours. The precipitate was filtered, washed with water,
Drying at 200 ° C for 12 hours,
Time, 300 ° C for 2 hours, 400 ° C for 1 hour, 510 ° C
For 16 hours to prepare a catalyst. 1.6% of Al ₂ O _{3 and} 0.1% of CaO were added to the prepared catalyst as a reinforcing material. Thus, a catalyst having a loading of 7.6% of nickel oxide on zinc oxide was obtained. The NO adsorption amount of the catalyst was 0.077 cc / m ² . The specific surface area of this catalyst was 105.5 m ² / g. The bulk specific gravity of the catalyst was 0.759 g / cc. Using this catalyst, an evaluation test of the catalyst life was performed under the same reaction conditions as in Example 1 except for the reaction temperature. Table 4 shows the results.

[0043]

[Table 4]

Comparative Example 1 27.0 g of zinc acetate and 77.8 g of nickel nitrate were added to 900
The mixture was dissolved in water to prepare a mixed solution of the two, and an aqueous solution of ammonium carbonate in which 22 g of ammonium carbonate was dissolved in 200 ml of water and 15% aqueous ammonia were added to this solution to precipitate zinc carbonate and basic nickel carbonate. Made and left for about 12 hours. This precipitate was filtered, washed with water, and then dried at 120 ° C. for 12 hours.
Drying at 200 ° C for 1 hour while introducing air
The catalyst was prepared by calcining at 00 ° C. for 2 hours, 400 ° C. for 1 hour, and 510 ° C. for 16 hours to obtain a catalyst having a nickel oxide loading on zinc oxide of 59.9%. The NO adsorption amount of the catalyst is 0.
It was 136 cc / m ² . The specific surface area of this catalyst was 18.4 m ² / g. The bulk specific gravity of the catalyst is 1.5
It was 5 g / cc. Using this catalyst, an evaluation test of the catalyst life was performed under the same reaction conditions as in Example 1. Table 5 shows the results.

[0045]

[Table 5]

Comparative Example 2 102.5 g of zinc acetate and 38.5 g of nickel nitrate were added to 10
The mixture was dissolved in 00 ml of water to prepare a mixed solution of the two. To this solution was added an aqueous solution of ammonium carbonate in which 22 g of ammonium carbonate was dissolved in 200 ml of water and 15% aqueous ammonia to precipitate zinc carbonate and basic nickel carbonate. Making, 12
Left for about an hour. The precipitate was filtered, washed with water, and then cooled to 120 ° C.
For 12 hours, and while introducing air, calcined at 200 ° C. for 1 hour, 300 ° C. for 2 hours, 400 ° C. for 1 hour, and 510 ° C. for 16 hours to prepare a catalyst. Further, 3.8% as Al ₂ O _{3 and} 2.7% as CaO were added to the prepared catalyst as a reinforcing material. Thus, a catalyst having a loading of 7.6% of nickel oxide on zinc oxide was obtained. The NO adsorption amount of the catalyst is 0.
008 cc / m ² . The specific surface area of this catalyst was 14.2 m ² / g. The bulk specific gravity of the catalyst was 1.2.
It was 95 g / cc. Using this catalyst, an evaluation test of the catalyst life was performed under the same reaction conditions as in Example 1 except for the reaction temperature. Table 6 shows the results.

[0047]

[Table 6]

From the results shown in Table 5, it can be seen that when the amount of adsorbed NO is high and the amount of Ni supported is 40% or more, a methanation reaction occurs and the CH ₄ concentration in the exhaust gas increases even if the catalyst has a long life. Also, from the results in Table 6, the amount of Ni carried was 4
It can be seen that the catalyst having a low NO adsorption amount does not cause methanation but has no catalytic activity even when the content is 0% by weight or less.

[0049]

According to the present invention, in the case where hydrogen used in a fuel system or the like is produced from medium-light oil such as kerosene which is easy to handle, the desulfurization step of the raw material is performed at a pressure of 30 kg / cm.
^{At 2} G or less, even in the presence of CO ₂ -containing hydrogen gas, it is possible to achieve very high depth desulfurization, suppress methanation reaction, have a long catalyst life, and have extremely high industrial value.

Continuation of front page (56) References JP-A-2-204301 (JP, A) JP-A-2-261540 (JP, A) JP-A-52-54668 (JP, A) JP-B-45-38981 (JP) , B1) (58) Field surveyed (Int.Cl. ⁶ , DB name) C10G 45/06

Claims (1)

(57) [Claims] 1. A method for desulfurizing a medium-to-light oil, wherein nickel or nickel oxide is supported on zinc oxide in an amount of less than 40% by weight in terms of metal in the presence of a hydrogen-containing gas. , 0.02cc / m
^Use a catalyst that has ^two or more nitric oxide adsorption capacities and a temperature of 1
80-440 ° C, LHSV 0.1-2h ^-1 , pressure 3
A method for deep desulfurization of medium and light oils, comprising desulfurizing under a condition of 0 kg / cm ² G or less.