JPH11335676A - Hydrogenation and denitrification of heavy oil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To regenerate a deactivated and unutilized catalyst and effectively utilize the catalyst due to the obtaining of suitable denitrification effects by regenerating the deactivated catalyst and optimizing the method for arranging the regenerated catalyst and a new catalyst when hydrodenitrifying a heavy oil. SOLUTION: When a heavy oil is hydrodenitrified in a reactional zone filled with a catalyst, a regenerated catalyst is disposed on the side of the former stage of the reactional zone and a new catalyst is disposed on the side of the latter stage of the reactional zone. The amount of the filled new catalyst in the reactional zone is preferably 20-95 vol.% and that of the regenerated catalyst is preferably 5-80 vol.% therein. The regenerating treatment of the catalyst is preferably carried out by a method for washing the used catalyst with a solvent such as toluene and then removing the carbonaceous material according to an oxidizing treatment. The regenerated catalyst preferably has 3-15 wt.% vanadium content, <=10 wt.% of carbon content, 100-200 m<2> /g specific surface area and 0.3-1.0 cc/g pore volume. A catalyst prepared by regenerating treatment of a catalyst, etc., supporting nickel on alumina is preferred.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a method for hydrodenitrogenation of heavy oil. More specifically, the present invention relates to a method for hydrodenitrogenation of heavy oil using a regenerated catalyst as a part of the catalyst.

[0002]

2. Description of the Related Art In petroleum refining, there are many steps for purifying various fractions by hydrotreating. Examples include desulfurization and denitrification of naphtha, kerosene, light oil, etc., and desulfurization and denitrification of heavy gas oil, and desulfurization and denitrification of residual oil and heavy oil. Among them, the catalyst used in the hydrotreating process for treating naphtha, kerosene, and gas oil, which have a relatively low boiling point and little content of metal impurities such as vanadium, has a low degree of deterioration due to use.

[0003] Further, the deterioration of these catalysts due to their use is due to the accumulation of almost a small amount of carbonaceous material, and they can be reused if they are removed by combustion or the like. Further, for the removal of carbonaceous material, a reusable catalyst can be obtained without requiring strict combustion control because the amount of carbonaceous material on the catalyst is small. Also, some catalysts that have been used once have a small degree of deterioration, and such a catalyst can be reused as it is. These catalysts are used again for the treatment of naphtha, kerosene, light oil and the like without any special care.

[0004] Recently, a catalyst for hydrotreating heavy gas oil or reduced pressure gas oil has been reused by regeneration or the like, and the method of regeneration and use has been established. For example, it is known that in a heavy gas oil hydrocracking process, both a hydrocracking catalyst and a hydrodenitrogenation catalyst for pretreatment thereof can be recycled by hydrogen activation or oxygen activation.

[0005] In the catalyst used for the hydrotreating of these distillate oils, there is almost no metal impurities in the raw material oil to be treated, so that the deposition of metals such as vanadium on the catalyst due to the raw material is small. Not only is carbonaceous deposition low,
The quality of carbonaceous material is also easy to burn, and the surface of the catalyst does not become so high even during regeneration by combustion, the change in the pore structure of the catalyst carrier and the loading state of the active metal phase are small, and heavy gas oil and decompression again It could be used to treat distillate such as light oil. (Stadies in Surface
and Catalysis vol. 88 P199
(1994)) However, in the hydrogenation treatment of heavy oil such as residual oil having a higher boiling point or a distillate that cannot be distilled, metal impurities and asphaltenes contained in the raw material oil tend to be carbonized. There are many components, which deposit a large amount of metal and carbon on the spent catalyst. In addition, the spent catalyst in which the metal content and the carbonaceous material have accumulated at the same time cannot be easily removed by burning the carbonaceous material. (C
atal. Todayvol. 17 No. 4 P53
9 (1993), Catal. Rev .. Sci. En
g. 33 (3 & 4) P281 (1991))
These spent catalysts were discarded without being reused.

[0006]

DISCLOSURE OF THE INVENTION The present invention provides a denitrification of heavy oil for regenerating and effectively utilizing a catalyst which has been deactivated by use in a hydrotreating process of heavy oil and the like and has not been used. The aim is to provide a method.

[0007]

Means for Solving the Problems As a result of intensive studies, the present inventors regenerated a catalyst deactivated by use in a hydrotreating process for heavy oil and the like, and arranged it with a new catalyst used at the same time. It has been found that a suitable denitrification effect can be obtained by optimizing, and that it is effective to control the amount of impurities and physical properties attached to the deactivated catalyst by a regeneration treatment. The present invention has been completed.

That is, the gist of the present invention is as follows. (1) In the case where heavy oil is hydrodenitrogenated in a reaction zone by filling a catalyst, a regenerated catalyst is disposed at a front stage of at least a part of the reaction zone, and a new catalyst is disposed at a rear stage thereof. Method for hydrodenitrogenation of heavy oils. (2) The charged amount of the fresh catalyst in at least a part of the reaction zones is 20 to 95% by volume, and the charged amount of the regenerated catalyst is 5%.
(1) The hydrodenitrogenation method according to (1), wherein the amount is from 80 to 80% by volume. (3) The hydrodenitrogenation method according to (1) or (2), wherein the vanadium content of the regenerated catalyst is 35% by weight or less based on the regenerated catalyst. (4) The hydrodenitrogenation method according to any one of (1) to (3), wherein the carbon content of the regenerated catalyst is 15% by weight or less based on the regenerated catalyst. (5) The hydrodenitrogenation method according to any one of (1) to (4), wherein the specific surface area of the regenerated catalyst is 60 to 200 m ² / g. (6) The hydrodenitrogenation method according to any one of (1) to (5), wherein the regenerated catalyst has a pore volume of 0.3 to 1.0 cc / g. (7) The regenerated catalyst is obtained by using a catalyst in which at least one kind of metal selected from molybdenum, tungsten, cobalt and nickel is supported on an oxide carrier in a hydrogenation process and then regenerated. (1) The hydrodenitrogenation method according to any one of (1) to (6). (8) The hydrodenitrogenation method according to (7), wherein the oxide carrier is alumina and the supported metal species is nickel and molybdenum. (9) The hydrodenitrogenation method according to (7), wherein the oxide carrier is alumina containing at least one of phosphorus, boron and silicon oxides, and the supported metal species is nickel or cobalt and molybdenum. . (10) The content of nickel or cobalt as the supported metal species is in the range of 0.1 to 10% by weight based on the regenerated catalyst, and the content of molybdenum is in the range of 0.1 to 25% by weight based on the regenerated catalyst. ) The hydrodenitrogenation method according to any one of (1) to (9).

[0009]

Embodiments of the present invention will be described below. The present invention is a hydrodenitrogenation method characterized by using a regenerated catalyst and a new catalyst in a specific combination when hydrodenitrogenating heavy oil in a reaction zone filled with a catalyst. That is, this is a hydrodenitrogenation method in which at least a part of the reaction zone is filled with a catalyst in which the regenerated catalyst is disposed in the front stage and the new catalyst is disposed in the rear stage.

In the heavy oil hydrotreating process, heavy oil is treated for various purposes. Although the main purpose is desulfurization, decomposition, and the like in many cases, these cases also often serve the purpose of reducing the nitrogen content of the produced oil.
For example, in a desulfurization process for producing heavy oil, the sulfur content, nitrogen content, and metal content of the product heavy oil are often important quality control items. In addition, heavy oil desulfurization process is sometimes used for pretreatment of catalytic cracking process for gasoline production, but as a raw material for catalytic cracking, reduction of not only sulfur content but also nitrogen content is an important factor . In some cases, as in the hydrocracking process, nitrogen compounds in the feedstock oil, which are poisons of the cracking catalyst, are preliminarily removed by a denitrification reaction.

Here, the denitrification treatment in the heavy oil hydrotreating process refers to various denitrification treatments as described above, and is carried out simultaneously with other reactions when the main purpose is a denitrification reaction. Or a denitrification treatment for pre-treatment or post-treatment of other reactions. In the case of the pretreatment of the cracking catalyst as in the above-described hydrocracking process, only the portion where the denitrification treatment is performed is referred to.

The catalyst to be charged into the reaction zone means not only a catalyst for the purpose of denitrification but also a catalyst for the purpose.
If it also serves as a denitrification reaction, it includes catalysts whose main purpose is desulfurization, descaling, and demetallization. Therefore, for example, a reaction zone in a heavy oil desulfurization process that also aims at denitrification is a reaction zone of a desulfurization process including a desulfurization zone, a demetalization zone, a descaling zone, etc., as well as a so-called narrowly defined denitrification reaction zone. It may also refer to the entire catalyst layer. Among them, at least a part of the reaction zone is a denitrification reaction zone in the narrow sense, a desulfurization reaction zone,
In addition to the demetallizing zone, the descaling zone, etc., the reaction zone may be the entire reaction zone, the reactor, or the bed portion in the reactor. Further, it may extend downstream of one reactor and upstream of the next reactor. In other words, it refers to a single part in which the denitrification reaction has occurred to some extent, regardless of the purpose or purpose.

Typical embodiments of some of the reaction zones include the case of the entire denitrification reaction zone, the case where a plurality of reactors are connected in series, and the case where a single reactor is used. Or only one bet in the reactor. In addition, the demetallization and denitrification reaction zone and the desulfurization and denitrification reaction zone are considered to be separate, and the arrangement method of the former stage and the latter stage in the demetallization and denitrification reaction zone, the former method and the latter stage of the desulfurization and denitrification reaction zone May be. However, a catalyst zone that does not participate in the denitrification reaction at all, for example, a catalyst zone that performs only hydrocracking, is not included in the denitrification reaction zone.

In the arrangement of the catalyst, it is important that at least a part of the reaction zone be a regenerated catalyst at the front stage and a new catalyst at the rear stage. This is because, in the denitrification reaction of heavy oil, the easily removable nitrogen compounds in the raw heavy oil are first removed by a hydrogenation reaction, and the remaining hard-to-react nitrogen compounds are hydrogenated by a relatively active new catalyst. This is because the reaction method of denitration and removal is an effective denitrification method. For this purpose, good results can be obtained by arranging a regenerated catalyst having a relatively low hydrogenation activity at the front stage and a new catalyst having a high activity at the rear stage.

In at least a part of the reaction zone of the hydrodenitrogenation process (hereinafter, referred to as a specific reaction zone),
In order to fully expect this effect, the new catalyst should be at least 20% of the specific reaction zone (volume% based on the total catalyst in the specific reaction zone with the catalyst charged, the same applies hereinafter), and preferably 4% or more.
It is preferable to use 0% or more. Conversely, 5% of regenerated catalyst
As described above, the improvement of the denitrification effect by the arrangement of the catalyst is not remarkable unless it is preferably used in an amount of 10% or more. The upstream side and downstream side of the catalyst arrangement indicate upstream and downstream of the flow of the reactant, and the upstream side is the upstream side and the downstream side is the downstream side.

The heavy oil in the present invention means a residue containing a distillation residue such as an atmospheric residue and a vacuum residue, and does not include a distillate consisting of only a distillate such as kerosene, gas oil, and vacuum gas oil. . Usually, heavy oil contains 1% by weight or more of sulfur, 200% by weight or more of nitrogen, 5% by weight or more of residual carbon, 5ppm or more of vanadium, and 0.5% or more of asphaltenes. For example, other crude oils such as the above-mentioned atmospheric residual oil, asphalt oil, pyrolysis oil, tar sand oil, or a mixed oil containing these oils can be used. The hydrodenitrification process of the present invention uses a fixed bed reactor, and does not assume a reaction type process such as a moving bed or a boiling bed. However, the flow of the reactant may be an upward flow or a downward flow.

Next, the new catalyst, the regenerated catalyst and the regenerating process will be described. First, the new catalyst is manufactured as a catalyst for hydrodenitrification of mineral oil, preferably heavy oil, or as a catalyst for hydrotreating heavy oil, desulfurization, demetallization,
It also refers to those that have denitrification activity at the same time as decomposition, such as generally available hydrodesulfurization catalysts, hydrodemetallation catalysts, or specially manufactured catalysts with hydrodenitrification function. Good.

These are not only those which have never been used in the hydrotreating process but also those which have been used in the hydrotreating process but whose use has been interrupted for a short time due to troubles in the equipment and used again as it is. Including. That is, a catalyst that has a sufficient denitrification activity that is assumed from the beginning, even if it is used temporarily and does not require any special activation treatment, is included.

The regenerated catalyst is a catalyst in which the above-mentioned new catalyst is once used for the hydrogenation treatment of heavy oil or the like, and a catalyst (hereinafter referred to as used catalyst) which cannot obtain sufficient denitrification activity by itself is regenerated. It has been activated. The hydrogenation treatment is generally a desulfurization treatment, but may be a hydrogenation treatment such as metal removal, nitrogen removal, aromatic removal, or decomposition. In addition, heavy oil is generally treated, but a regenerated treatment of a used catalyst used for hydrotreating a distillate such as heavy light oil may be used. It suffices if the regenerated catalyst can be used for hydrodenitrogenation of heavy oil.

The regeneration treatment includes removal of oil and the like by washing with a solvent, removal of carbonaceous matter, sulfur and nitrogen by combustion, and selection of a catalyst having a normal shape by removing agglomerated or finely divided catalyst. However, the regeneration treatment in the present invention refers to a treatment including removal of carbonaceous matter by oxidation, preferably removal treatment of carbonaceous matter by oxidation outside the reactor. It is not necessary to completely remove the carbonaceous material in the regeneration treatment.

As a particularly preferred regeneration treatment, the used catalyst is first washed with a solvent. As the solvent, petroleum such as toluene, acetone, alcohol, naphtha, kerosene, and light oil are preferable. Any other solvent may be used as long as it is a solvent that can easily dissolve the organic substances attached to the used catalyst. This washing treatment can also be achieved by circulating light oil for washing while the catalyst is in the hydrotreating reactor, and then drying by passing nitrogen gas at about 50 to 200 ° C. Alternatively, the light oil may be circulated and washed and then withdrawn as it is, kept wet with light oil to prevent heat generation and spontaneous ignition, and dried when necessary. There is also a method of pulverizing a lump from the spent catalyst extracted from the reactor, removing a powdered catalyst, scale, and the like, washing the same with light oil, and further washing with naphtha to facilitate drying. In the case of a small amount, washing with toluene is suitable for completely removing the oil.

In order for the catalyst from which oil and impurities have been removed by washing to exhibit sufficient activity, it is necessary to further remove carbonaceous matter by oxidation treatment. The oxidation treatment is generally performed by a combustion treatment in which the ambient temperature and the oxygen concentration are controlled. If the ambient temperature is too high or the oxygen concentration is too high, the temperature of the catalyst surface will be high, and the crystal form and the state of the supported metal will change, and the pores of the carrier will decrease, resulting in a decrease in catalytic activity. On the other hand, if the ambient temperature is too low or the oxygen concentration is too low, the removal of carbonaceous material by combustion becomes insufficient, and sufficient activity recovery cannot be expected. A desirable ambient temperature is 20
The temperature is from 0 to 800 ° C, particularly preferably from 300 to 600 ° C.

It is desirable to control the oxygen concentration in the range of 1 to 21%, but it is preferable to control the oxygen concentration in accordance with the combustion method, particularly, the contact state between the combustion gas and the catalyst. The surface temperature of the catalyst is controlled by adjusting the ambient temperature, oxygen concentration, flow rate of the ambient gas, etc., to prevent the specific surface area and pore volume of the regenerated catalyst from decreasing, and to reduce the hydrogenation active metals such as nickel and molybdenum. It is important to suppress changes in the crystal structure and the state of supporting the crystal particles.

It is desirable that the catalyst subjected to the combustion treatment be removed from the powdered one and the like, and that only the catalyst having a normal shape be used as the regenerated catalyst. If this operation is not performed, the initial activity may be sufficiently obtained, but the catalyst layer may be clogged or drifted, or the pressure loss of the fluid in the reactor may be increased, and normal operation may not be continued. Next, the composition and physical properties of the regenerated catalyst will be described.

Indicators of degradation due to use in the hydrotreating process include vanadium and carbonaceous materials. Vanadium is not usually contained as a catalyst component, but is caused by trace impurities contained in a feed oil to be hydrotreated, and can be used as an index of deterioration due to use. The vanadium content is 35% on the basis of the regenerated catalyst. (The metal content in the catalyst is the weight of the metal as an oxide based on the target catalyst which has been oxidized at 400 ° C. or more before measurement and no longer loses weight.) %, The same applies to the following metal content), preferably 20% or less, more preferably 3 to 15% or less. If the vanadium content exceeds 35%, the activity of the regenerated catalyst is too low, and the denitrification reaction as a whole does not proceed sufficiently. When the vanadium content is less than 2%, sufficient activity remains in the regenerated catalyst itself, and the difference in the denitrification effect due to the arrangement of the catalyst often decreases. Therefore, when the vanadium content is 2 to 35%, preferably 3 to 15% or less, the effect of drawing out the activity of the regenerated catalyst by the catalyst arrangement becomes better.

For elemental analysis of vanadium and the like, Mo, P, and V were dissolved in an acid after calcination of the sample at 650 ° C. for one hour, and Co, N
i and Al were measured by X-ray fluorescence analysis using a mixture of ash and lithium tetraborate as glass beads by high-frequency heating. The carbon content is also 15% (the carbon content in the catalyst is determined based on the amount of carbon contained in the target catalyst based on the value of the target catalyst that has been oxidized at 400 ° C. or more before measurement and has not been reduced. It should be expressed in terms of% by weight. Although the carbon content is often about 10 to 70% in the used stage, the carbon content can be removed from the catalyst by the regeneration treatment to reduce the content. If the carbon content is too large, this will cover the catalyst surface and reduce the catalytic activity, but if the carbon content is reduced by the regeneration treatment, the activity can be recovered. In addition, carbon and sulfur were analyzed by a CS simultaneous analyzer.

In the regeneration treatment, oxidation treatment, particularly a general method, involves combustion treatment. At that time, the surface of the catalyst is overheated, and the pore structure of the catalyst and the loaded state of the loaded metal change.
The catalyst activity may be reduced. Indices for evaluating these include the specific surface area and pore volume of the catalyst. The specific surface area and pore volume of the catalyst gradually decrease during use in the hydrogenation reaction due to adhesion of impurities and deterioration due to heat during the reaction. It is preferable that about 70% of the specific surface area and the pore volume of the new catalyst before use are retained.
This, physical properties and to Come In each specific surface area 60~200m ² / g of regenerated catalyst, preferably 100 to 200 m ² / g, it is desirable that the pore volume 0.3~1.0cc / g. These measurements were performed by the nitrogen adsorption method.

Since this regenerated catalyst is a catalyst used for hydrodenitrogenation of heavy oil, it must be originally a catalyst having hydrodenitrogenation ability. The basic catalyst composition for this purpose is an oxide carrier such as alumina or alumina.
A carrier in which molybdenum, tungsten, cobalt or nickel oxide is supported on a phosphorus, alumina / boron carrier, alumina / silicon carrier or the like is preferably used. Among these, nickel-molybdenum-supported / alumina-supported catalyst, nickel-molybdenum-supported / alumina-phosphorus-supported catalyst, cobalt-molybdenum-supported / alumina-boron-supported catalyst, and nickel-molybdenum-supported / alumina-silicon-supported catalyst are particularly preferable. Furthermore, since it is a heavy oil treatment, the supported metal, cobalt or nickel, is 0.1 to 1%.
It is preferable to contain 0% (weight% as an oxide with respect to the regenerated catalyst, the same applies hereinafter) and 0.2 to 25% of molybdenum. The content of phosphorus is preferably 0.1 to 15% (the same standard as the metal content).

Next, the hydrodesulfurization treatment including the hydrodenitrogenation treatment of heavy oil, which is one embodiment of the present invention, will be specifically described. If the above-mentioned catalyst arrangement method is adopted, the reaction conditions are not particularly limited, but will be described with general conditions. As for the arrangement of the catalyst, a new catalyst for demetallization is used in the demetallization zone, a new catalyst for desulfurization and denitrification is used in the first 50% of the desulfurization and denitrification reaction zone, and a regenerated catalyst for use in the latter 50%. Is preferably filled. As the heavy oil, those described above may be used, but a normal pressure residual oil is preferably used. In this case, the reaction temperature is 300 to 450 ° C., preferably 350 to 420 ° C., the hydrogen partial pressure is 7.0 to 25.0 Pa, preferably 10.0 to 15.0 Pa, and the liquid hourly space velocity is 0.01 to
10h ^-1 Preferably 0.1~5h ^-1, a hydrogen / feed oil ratio of 5
00~2500Nm ³ / kl preferably 500~2000Nm ³ /
Conditions in the range of kl are preferred.

The nitrogen content, sulfur content, and metal content (nickel, vanadium) of the produced oil may be adjusted by appropriately selecting necessary conditions such as the reaction temperature from the above reaction conditions. As described above, the use of the heavy oil hydrodenitrogenation method of the present invention makes it possible to effectively utilize a spent catalyst which has been considered to be unusable in the past, and to perform a denitrification treatment of residual oil and the like.

[0031]

EXAMPLES Next, the present invention will be described in detail with reference to examples, but the present invention is not limited to these examples. [Example 1] Middle-east ordinary pressure residual oil was passed through a hydrodesulfurization unit for residual oil using a commercially available alumina-supported catalyst supporting nickel / molybdenum (referred to as New Catalyst 1) for 8000 hours.
The hydrodesulfurization treatment was continued while adjusting the reaction temperature so that the sulfur content of the main component (the boiling point fraction of 343 ° C. or higher) in the produced oil was constant, to obtain a used catalyst. Table 1 shows the properties of typical atmospheric residual oil that has passed through, and Table 2 shows the reaction conditions in the desulfurization unit.

The used catalyst is taken out of the reactor,
After sufficiently washing with toluene, it was dried. This washing catalyst was oxidized at 500 ° C. for 3 hours in a stream of air. Table 3 shows the composition and physical properties of each catalyst (referred to as regenerated catalyst 1). Small high pressure fixed bed reactor (capacity 2
(00 cc), 50 cc of the regenerated catalyst 1 was filled in the first stage, and 50 cc of the new catalyst 1 was packed in the second stage. This is converted to the sulfurizing agent D
Light gas oil, to which MDS was added to adjust the sulfur concentration to 2.5%, was passed through a 135 kg / cm ³ hydrogen stream at 250 ° C. for 24 hours to carry out preliminary sulfurization treatment. Thereafter, a hydrodenitrogenation reaction was carried out using the normal pressure residual oil. The reaction conditions are shown in Table 6, and the properties of the produced oil are shown in Table 7.

Example 2 The same operation as in Example 1 was carried out except that 25 cc of the regenerated catalyst 1 was charged to the front stage of the small high-pressure fixed bed reactor (capacity: 200 cc), and 75 cc of the new catalyst 1 was charged to the rear stage. went. Table 7 shows the properties of the resulting oil.

Example 3 Commercially available nickel / molybdenum supported alumina / phosphorus supported catalyst (referred to as New Catalyst 2)
The washing catalyst 2 and the regenerated catalyst 2 were obtained by the same operation as in [Example 1]. Table 4 shows the composition and physical properties of each catalyst. Small high pressure fixed bed reactor (capacity 200cc)
The same operation as in [Example 1] was performed except that 50 cc of the regenerated catalyst 2 was filled in the first stage and 50 cc of the new catalyst 2 was filled in the second stage. Table 7 shows the properties of the resulting oil.

Example 4 In Example 1, the fresh catalyst 1 was passed through a Middle Eastern vacuum gas oil for 8000 hours in a vacuum gas oil hydrodesulfurization unit. The hydrodesulfurization treatment was continued while adjusting the reaction temperature so that the sulfur content of the main component (the boiling point fraction of 360 ° C. or higher) in the produced oil was constant, to obtain a used catalyst. Table 1 shows the properties of the vacuum gas oil, and Table 2 shows the reaction conditions in the desulfurization unit. From this used catalyst, a washing catalyst 3 and a regenerated catalyst 3 were obtained in the same manner as in [Example 1]. Table 5 shows the composition and physical properties of each catalyst. 50c of regenerated catalyst 3 in front of small high pressure fixed bed reactor (capacity 200cc)
c, The same operation as in [Example 1] was performed except that 50 cc of the new catalyst 1 was filled in the subsequent stage. Table 7 shows the properties of the resulting oil.

[Comparative Example 1] The same operation as in [Example 1] was performed except that 50 cc of the new catalyst 1 was charged in the front stage of the small high-pressure fixed bed reactor (capacity: 200 cc), and 50 cc of the regenerated catalyst 1 was charged in the rear stage. went. Table 7 shows the properties of the resulting oil. [Comparative Example 2] Small high-pressure fixed-bed reactor (capacity 200 cc)
The same operation as in [Example 2] was performed except that 75 cc of the new catalyst 1 was filled in the first stage and 25 cc of the regenerated catalyst 1 was charged in the second stage. Table 7 shows the properties of the resulting oil. [Comparative Example 3] Small high-pressure fixed-bed reactor (capacity 200 cc)
The same operation as in [Example 3] was performed except that 50 cc of the new catalyst 2 was filled in the first stage and 50 cc of the regenerated catalyst 2 was charged in the second stage. Table 7 shows the properties of the resulting oil. [Comparative Example 4] Small high-pressure fixed-bed reactor (capacity 200 cc)
The same operation as in [Example 4] was performed except that 50 cc of the new catalyst 1 was filled in the first stage and 50 cc of the regenerated catalyst 3 was filled in the second stage. Table 7 shows the properties of the resulting oil.

[0037]

[Table 1]

[0038]

[Table 2]

[0039]

[Table 3]

[0040]

[Table 4]

[0041]

[Table 5]

[0042]

[Table 6]

[0043]

[Table 7]

[0044]

In the method for hydrodenitrogenation of heavy oil according to the method of arranging catalysts according to the present invention, a good denitrification reaction of residual oils and the like is carried out under the same conditions as those for denitrification using an ordinary new catalyst. It can be carried out and shows an excellent effect as a method for effectively using the used catalyst.

Claims (10)

[Claims] 1. A method for arranging a regenerated catalyst at the front of at least a part of a reaction zone and a new catalyst at a rear of a reaction zone for hydrodenitrogenation of heavy oil in a reaction zone filled with the catalyst. A method for hydrodenitrogenation of heavy oil, comprising: 2. The hydrodenitrogenation method according to claim 1, wherein the charged amount of the fresh catalyst is 20 to 95% by volume and the charged amount of the regenerated catalyst is 5 to 80% in at least a part of the reaction zones. 3. The method according to claim 1, wherein the vanadium content of the regenerated catalyst is 35% by weight or less as an oxide based on the regenerated catalyst. 4. The hydrodenitrogenation method according to claim 1, wherein the carbon content of the regenerated catalyst is 15% by weight or less based on the regenerated catalyst. 5. The regenerated catalyst has a specific surface area of 60 to 200 m ² / g.
The hydrodenitrogenation method according to any one of claims 1 to 4, wherein 6. The regenerated catalyst has a pore volume of 0.3 to 1.0 cc.
The hydrodenitrogenation method according to any one of claims 1 to 5, wherein the ratio is / g. 7. A regenerated catalyst comprising: molybdenum on an oxide carrier;
The catalyst which supports at least one kind of metal selected from tungsten, cobalt and nickel is used in a hydrogenation process and then regenerated.
The method for hydrodenitrogenation according to any one of the above. 8. The hydrodenitrogenation method according to claim 7, wherein the oxide carrier is alumina and the supported metal species are nickel and molybdenum. 9. The hydrogenation according to claim 7, wherein the oxide carrier is alumina containing at least one of phosphorus, boron and silicon oxides, and the supported metal species is nickel or cobalt and molybdenum. Denitrification method. 10. The content of nickel or cobalt as a supported metal species is 0.1 to 10% by weight based on the regenerated catalyst, and the content of molybdenum is 0.1 to 25 based on the regenerated catalyst.
The hydrodenitrogenation process according to any of claims 7 to 9, which is in the range of% by weight.