JP3846966B2 - Hydrodehydration catalyst for hydrocarbon oil and method for hydrodemetallation of hydrocarbon oil using the same - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a hydrodemetallation catalyst for hydrocarbon oils and a hydrodemetallation method for hydrocarbon oils using the catalyst, and more particularly, in the case of hydrotreating hydrocarbon oils, particularly heavy oils, over a long period of time. The present invention relates to a hydrodemetallation catalyst capable of continuous operation over a long period of time and a hydrodemetallation method for hydrocarbon oils using the catalyst.
[0002]
TECHNICAL BACKGROUND OF THE INVENTION
High boiling hydrocarbon oils such as petroleum-based distillation residue oil and tar sand oil obtained by atmospheric distillation or distillation under reduced pressure contain a large amount of impurities such as metals, sulfur compounds, nitrogen compounds, In order to provide various fuels or chemical industrial raw materials, the hydroprocessing method is applied today as the most general purification method.
[0003]
In particular, in recent years, there has been a tendency for feedstocks to become heavier, which has led to an increasing need to resolve technical problems related to demetalization in addition to conventional desulfurization, denitrogenation, and lightening. Yes.
[0004]
One of the problems in the process technology of heavy oil hydroprocessing is the achievement of high desulfurization rate, the removal of metal components as contaminants, and the effect on catalyst performance due to metal deposition on the catalyst. It is how to reduce.
[0005]
In general, the metal component such as an organometallic compound contained in the raw material is different from the case of a sulfur compound or a nitrogen compound, and an unreacted portion is formed on the catalyst in a state of a metal sulfide or the like as the reaction proceeds. Except for this, it has a peculiar phenomenon that it is substantially entirely deposited and is not discharged out of the reaction system throughout the operation period. ing.
[0006]
In addition, the heavy oil hydrotreating process involves precipitation of a carbonaceous material (hereinafter sometimes referred to as carbon or carbon) due to a hydrocarbon decomposition reaction, which is also an inevitable side reaction.
[0007]
These deposited substances constitute a main factor of an increase in pressure loss (hereinafter sometimes referred to as ΔP increase) in a fixed bed reactor configured by filling a granular catalyst.
In general, in heavy oil hydroprocessing processes, the catalyst charged to the reactor is considered to function effectively over the entire packed bed during one continuous period of operation (eg, active metal species, loadings). Etc.) and the filling amount is determined, but in actual operation, a rapid increase of ΔP occurs before the planned oil flow amount, and it is experienced that the operation becomes impossible.
[0008]
In other words, as long as the combination of feedstock and catalyst is appropriate, the activity of the post-desulfurization catalyst decreases on schedule before the increase of ΔP in the first direct desorption column (demetallization reaction column), and the operation ends. However, the cause of unscheduled desulfurization catalyst deactivation in this case is that the capacity of the demetallization catalyst layer is lowered in the latter stage of operation, and heavy metal components in the feedstock are acceleratedly deposited on the desulfurization catalyst. In addition, in the latter period of operation, the catalyst layer temperature is increased to compensate for the decrease in the catalyst performance as the performance of the demetallation catalyst and the desulfurization catalyst decreases. However, coking on the catalyst becomes remarkable as the temperature increases. Is also a cause of desulfurization catalyst deterioration. As described above, the catalyst deterioration and the catalyst layer clogging tendency rapidly develop in the latter half of the operation, and the operation management of the direct desorption apparatus is good to end the scheduled operation immediately before this. In this case, although the latter stage of the demetalization catalyst layer still has the metal removal capability, the performance of the demetalization catalyst layer as a whole is insufficient. As a countermeasure, it is conceivable to increase the amount of catalyst in the demetalization catalyst layer. However, in this case as well, the problem of clogging the uppermost catalyst layer at the entrance of the demetallation catalyst layer cannot be solved. Although the metal removal capability is largely retained (for catalyst enhancement), the operation period cannot be substantially extended due to an increase in pressure loss.
[0009]
The present inventors examined the reaction mechanism in the catalyst layer from the observation results of the used catalyst of the direct desorption apparatus and the demetallation reaction test in the laboratory, and found that the following phenomenon exists on the catalyst. .
[0010]
That is, at the initial stage of use of the demetallation catalyst, demetallation preferentially proceeds in the catalyst particles in which active metal species such as molybdenum are present, and heavy oil contaminated metals such as vanadium and nickel in the heavy oil are contained in the catalyst particles. Precipitates and is retained.
[0011]
When a large amount of vanadium or the like is accumulated in the catalyst particles after the demetalization time has elapsed, the active metal (hereinafter represented by molybdenum) in the catalyst particles gradually moves to the catalyst particle surface layer to form a concentrated layer. Furthermore, a molybdenum layer is formed on the outer layer of the catalyst particles. Molybdenum present in the outer layer of the catalyst particles has catalytic activity and exhibits an action of fixing vanadium, nickel, and iron in the heavy oil to the outer layer of the catalyst particles.
Furthermore, when the demetallation treatment time has elapsed, the outer layer of catalyst particles composed of molybdenum, vanadium, nickel, sulfur, iron, carbon precursors, etc. expands and demetalizes due to the catalytic action of the metals present in this layer. All metal catalyst particle gaps are filled. At this time, in the demetallized catalyst layer, the entire space of the catalyst layer including the space between the catalyst particles is filled with solid precipitates, the catalyst layer pressure loss increases rapidly, and the direct desorption apparatus becomes inoperable.
[0012]
The solution to the problem related to the increase in ΔP of the catalyst layer in the hydrodemetallation method of heavy oil has been one of the long-standing themes in the technical field.
In U.S. Pat. No. 4,510,263, the catalyst charged in the reactor is cross-shaped on the inner wall of a cylindrical extrudate with a small increase in ΔP compared to a catalyst made of a sphere or a columnar molded product. The mechanical strength is improved and the active surface is expanded by providing beam vanes or ribs having a cross-section such as a shape. In contrast,
In Japanese Patent Laid-Open No. 63-194732, as a method for solving the problem of clogging and activity reduction, the concentration distribution of the active metal component in the catalyst carrier is maximized between the center and the outer surface on the cut surface of the catalyst carrier. By prescribing in this way, the reaction on the outer surface of the catalyst is suppressed, and the reaction in the region is selectively prioritized to reduce the amount of precipitation on the outer surface.
In JP-A-2-3055891, the surface of the catalyst carrier particles has a specific surface area of 1 m ² / g or less and a pore diameter of 10 μm or more, thereby reducing the number of active sites on the outer surface of the catalyst. Priority is given to the reaction in the pores, and at the same time, the capacity of the deposited substance is expanded to suppress the expansion of the catalyst volume and to solve the clogging problem.
[0013]
However, the present inventors diligently examined the prior art including the invention described in the above publication, and as a result, the raw material situation that is going to become heavier in the future and the economic improvement by long-term continuous operation of the process equipment. We acknowledged that we could not respond adequately to requests that wanted
For example, the catalyst described in US Pat. No. 4,510,263 can provide a relatively large flow path for the reaction fluid in the hydrodemetallation process, but is a permanent solution. I can't.
[0014]
Thus, based on the above viewpoint, the present inventors have made the present invention in order to meet the needs for the future heavy-duty feedstock and long-term continuous operation of the process using the hydrodemetallation method. Is.
[0015]
OBJECT OF THE INVENTION
The present invention has been made on the basis of the above-described research, and in hydrotreating hydrocarbon oils, particularly heavy oils, by preventing precipitation of heavy metals and the like between catalyst particles, Prevents clogging of the layers, maintains the space between the catalysts to prevent differential pressure rise, allows hydrodemetallation of heavy oil continuously over a long period of time, and prevents sticking between the catalysts Accordingly, an object of the present invention is to provide a hydrodemetallation catalyst for hydrocarbon oil that facilitates catalyst extraction after the end of operation and a hydrodemetallation method for hydrocarbon oil using this catalyst.
[0016]
SUMMARY OF THE INVENTION
Hydrodehydration catalyst for hydrocarbon oil according to the present invention,
A carrier and a catalyst component supported on the carrier;
It has a reaction flow path through which a reaction fluid flows inside the catalyst, and has a coating layer made of an inert substance that does not substantially have a metal removal function on at least a part of the catalyst surface.
[0017]
The catalyst is preferably a cylindrical body having a single through-hole as a reaction channel, a cylindrical body having a plurality of through-holes, and a honeycomb structure having a plurality of through-holes. The diameter is preferably 1 to 10 mm.
[0018]
In the present invention, the coating layer may be provided on the surface of the columnar body of the columnar catalyst, or may be provided on the surface of the columnar body and the end surface.
The specific surface area of the coating layer is preferably 10 m ² / g or less.
[0019]
The coating layer as described above is a dense layer that does not substantially allow the reaction fluid to permeate, thereby preventing the reaction fluid from contacting the catalytically active sites. Examples of the inert substance that forms such a coating layer include glass, inert ceramics, and metals that are inert under reaction conditions.
[0020]
As the glass, low-temperature sintered glass, solder glass or glaze is preferable.
Examples of the inert ceramic include α-alumina, inert silica, cordierite, mullite, and quartz.
[0021]
Examples of the metal that is inert under the reaction conditions include aluminum and stainless steel.
The catalyst as described above is suitable as a fixed bed filling catalyst.
[0022]
The hydrodemetallation method for hydrocarbon oil according to the present invention is characterized in that hydrocarbon oil is hydrotreated in the presence of the hydrodemetallation catalyst as described above.
In the present invention, the hydrotreating of the hydrocarbon oil is preferably performed in a fixed bed type, and the uppermost initial catalyst layer in the contact between the hydrocarbon oil and the hydrodemetallation catalyst (the uppermost packed catalyst layer) is It is preferable to use a hydrodemetallation catalyst.
[0023]
In the present invention, at least a part of the outer surface (catalyst surface) that determines the shape of the catalyst when viewed from the macroscopic viewpoint is inactive with respect to hydrodemetallation or contact with the active point of the reaction fluid. Therefore, a surface on which no metal and carbon are deposited is secured, and a flow path for the reaction fluid is formed through the surface.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the hydrodemetallation catalyst for hydrocarbon oil and the hydrodemetallation method for hydrocarbon oil using the catalyst according to the present invention will be described in detail.
[0025]
Hydrodemetallation catalyst The hydrodemetallation catalyst according to the present invention comprises a support and a catalyst component (catalytic active component) supported on the support, and a reaction fluid flows through the catalyst. In addition to having a flow path, at least a part of the catalyst surface is made of an inert substance that does not substantially have a metal removal function and has a coating layer that does not substantially allow the reaction fluid to permeate. Such a coating layer prevents contact between the reaction fluid and the catalyst active point.
[0026]
In the present invention, known carriers such as alumina, silica, silica-alumina, titania, magnesia, and silica-magnesia can be used as the carrier for forming the hydrogenation catalyst without particular limitation.
The specific surface area of these carriers (BET method) is 50 m ² / g or more, preferably 100 to 300 m ² / g.
[0027]
As the catalyst component supported on the carrier, catalyst components known as hydrogenation catalysts can be widely used. For example, Group VIB metals such as molybdenum, tungsten and chromium, or Group VIII metal oxides such as nickel and cobalt Alternatively, a sulfide can be used.
[0028]
In the present invention, a single catalyst component may be supported on the support, or a combination of two or more may be supported, but among these, it is preferable to support a combination of molybdenum and nickel and / or cobalt. .
The catalyst component as described above is preferably supported as an oxide in an amount of 5 to 30% by weight of the Group VIB metal and 1 to 10% by weight of the Group VIII metal.
[0029]
The catalyst component as described above can be supported on the catalyst by a conventionally known method. For example, an impregnation method in which a support (molded body) is impregnated with an aqueous catalyst component solution, an unmolded catalyst raw material and a catalyst component or an aqueous catalyst component solution. It can be supported by a kneading-extrusion molding method in which kneading and extrusion are performed, a coating method in which a carrier (molded body) is coated with a catalyst component, or the like.
[0030]
A hydrodemetallation catalyst comprising a carrier as described above and a catalyst component supported on the carrier has a single or a plurality of reaction channels through which the reaction fluid flows, and the surface of the channel is The shape is not limited as long as it is formed so that a metal removal reaction can occur. For example, it is preferably a columnar shape, and the cross-section is preferably a circular shape, a star shape, a square shape, a triangular shape such as a triangle, a hexagon, or an octagon.
The size of the catalyst is not particularly limited as long as it can be molded and can be used in the reaction tower.
[0031]
As long as the reaction channel is a hole communicating with both end faces, it may be a through hole or an irregular hole such as a filter mold. Preferably there is.
[0032]
It is preferable that the equivalent diameter (cross-sectional area × 4 / peripheral length of the cross section) of the reaction channel (flow hole) is about 1 to 10 mm. With such a diameter, the hydrocarbon oil can be sufficiently circulated regardless of the gas phase or the liquid phase, the contact reaction surface can be secured, and the strength can be sufficiently secured.
[0033]
When the equivalent diameter is less than 1 mm, the flow rate of hydrocarbon oil decreases, while when it exceeds 10 mm, the contact reaction surface decreases.
Specific examples of the catalyst having such a reaction channel include a cylindrical body (Raschig ring) having a single through hole, a cylindrical body having a plurality of through holes, and a honeycomb structure having a plurality of through holes. Can be mentioned.
[0034]
Among these, a columnar catalyst having a plurality of through holes is preferable.
This catalyst preferably has a porosity of about 40% or more.
As described above, since the hydrodemetallation catalyst according to the present invention has large voids inside, metal deposits, carbonaceous deposits, and the like are accumulated in these voids.
[0035]
In the present invention, at least a part of the catalyst surface of the catalyst as described above is provided with a coating layer that is made of an inert substance that does not substantially have a metal removal function and does not substantially allow the reaction fluid to permeate. In such a catalyst, a coating layer is not provided on the reaction channel surface inside the catalyst, and a reaction surface (a contact surface with the reaction fluid) is formed on the reaction channel surface.
[0036]
Such a coating layer is a layer that does not substantially permeate the reaction fluid (hydrocarbon oil), and generally does not allow the reaction fluid to substantially permeate so that the reaction fluid does not contact the catalytically active sites. Is a layer. This coating layer can prevent the reaction fluid from contacting the active site without allowing the reaction fluid to permeate, or can prevent the catalyst component from diffusing to the catalyst surface, and thereby the catalyst provided with the coating layer. Prevents hydrocarbon metal demetallation or carbonaceous precipitation reaction on the surface, maintains catalyst gaps without accumulating metal or carbonaceous material between catalyst particles, and reduces hydrocarbon oil flow in the catalyst layer. To maintain.
[0037]
In the present specification, a coating layer that does not substantially permeate the reaction fluid means a coating layer that does not allow the reaction fluid to permeate at all, or allows a very small amount of reaction fluid to permeate. It means a coating layer in which carbonaceous matter is deposited and the catalysts are not fixed to each other.
[0038]
Specifically, the coating layer has a small specific surface area and substantially no pores, hardly retains the catalyst component and the metal component precipitated from the reaction fluid (hydrocarbon oil), and the catalyst component supported inside the catalyst has It is preferable to be made of a material that prevents exudation on the surface of the coating layer and further does not allow permeation of hydrocarbon oil.
[0039]
More specifically, the specific surface area of the coating layer should be 10 m ² / g or less, preferably 1 m ² / g or less, and if it exceeds 10 m ² / g, the non-retaining properties of the above metal components, the catalyst components The exudation prevention property, the permeation prevention property of the reaction fluid, etc. are deteriorated.
[0040]
As a material for forming the coating layer, a reaction-inert material can be used without particular limitation as long as the above-described purpose can be achieved. For example, it is inactive under glass, inert ceramics or reaction conditions. A simple metal or the like can be used.
[0041]
As glass, glaze, low-temperature sintered glass such as sodium-boron, lead-boron, silicon-boron, etc., solder glass such as zinc-boron, lead-silicon, etc. can be used and are inert. Examples of ceramics that can be used include α-alumina, inert silica, cordierite, mullite, and quartz. Aluminum, stainless steel, or the like can be used as a metal (including an alloy) that is inert under the reaction conditions.
Two or more of these may be used in combination, for example, low temperature sintered glass and inert ceramics may be used in combination.
[0042]
Examples of the catalyst having a coating layer on at least a part of the catalyst surface are shown in FIGS. In the drawings shown below, the carrier 3 carries a catalyst component.
The catalyst 1 shown in FIG. 1 has a structure in which a coating layer 2 is provided on the entire outer surface of the body (circular edge) of a Raschig ring-shaped carrier 3 having a single through hole 4.
[0043]
The catalyst 1 shown in FIG. 2 has a structure in which a coating layer 2 is provided on the entire outer surface of the body of a cylindrical carrier 3 having a plurality of through holes 4.
The catalyst 1 shown in FIG. 3 has a structure in which a coating layer 2 is provided on a part of the outer peripheral surface of a body of a columnar carrier 3 having a plurality of through holes 4.
[0044]
The catalyst 1 shown in FIG. 4 has a structure in which a coating layer 2 is provided on the entire surface of the outer periphery of the body of a columnar carrier 3 having a plurality of through holes 4.
The catalyst 1 shown in FIG. 5 has a structure in which a coating layer 2 is provided on a part of the outer peripheral surface of a body portion of a columnar carrier 3 having a plurality of through holes 4.
[0045]
The catalyst 1 shown in FIG. 6 has a structure in which a coating layer 2 is provided on the surface of a body protrusion 3a of a cylindrical carrier 3 having a plurality of through holes 4 and having protrusions 3a on the body.
The catalyst 1 shown in FIG. 7 has a structure in which a coating layer 2 is provided on the entire surface of the outer periphery of the trunk portion of the honeycomb carrier 3 having a plurality of through holes 4.
[0046]
Among the above, a columnar catalyst having a plurality of through holes 4 as shown in FIGS.
In the present invention, the catalyst and the coating layer are not limited to the shapes shown in these drawings.
[0047]
The formation method is not particularly limited as long as it can be formed on at least a part of the catalyst surface, and is formed by a method suitable for each material as described above. For example, a catalyst can be obtained by spraying a sol or slurry of glaze or inert ceramic on a part or the entire surface of the catalyst, brushing it, or immersing only the part where the coating layer is to be formed in the sol or slurry, and then firing. A coating layer can be formed on part or the entire surface. Thus, when forming the coating layer by the dipping method, for example, when forming the coating layer on the body of the columnar catalyst, the end face may be masked and immersed in the sol or slurry, or the sol or The columnar body portion may be brought into contact with the slurry liquid or the liquid film. The extruded product is cut into a desired size in these processes.
[0048]
The coating layer formed using glass or inert ceramic as described above is fired at a temperature equal to or higher than the hydroprocessing temperature of the hydrocarbon oil, but maintains the specific surface area of the reaction surface to the maximum and loses the active component. From the viewpoint of not activating, it is usually preferable to fire at a temperature of 450 to 700 ° C.
[0049]
Moreover, when forming a metal coating layer on the catalyst surface, a thermal spraying method or a melt bonding method can be used.
Although the catalyst component can be supported before forming the coating layer, the catalyst component is hardly supported on the coating layer even if the coating layer is formed in advance. A catalyst component can also be supported.
Prior to forming the coating layer as described above, the catalyst carrying the catalyst component may be dried and pre-fired.
[0050]
The hydrodemetallation catalyst according to the present invention is composed of an inert substance that does not substantially have a demetallizing function on the catalyst surface, and has a coating layer that does not substantially permeate the reaction fluid. Has a reaction channel and the catalyst exhibits a sufficient reaction activity.
Such a coating layer formed on the catalyst surface is formed on at least a part of the catalyst surface so as to prevent the reaction of the hydrocarbon oil on the catalyst surface and prevent the clogging of the catalyst. However, it may be provided on the outer peripheral surface or the end surface of the body of the columnar catalyst, but both the body and the end, that is, the entire surface of the catalyst may be covered. Usually, the coating layer is provided on the surface of the catalyst body. Specifically, 30 to 100%, preferably 30 to 98% of the catalyst surface area can be coated.
[0051]
Thus, if almost the entire surface of the catalyst is coated at a coverage of 100% (preferably 98%), the deposition of metal or the like on the surface is greatly limited. A relatively large space can be maintained and secured, and the problem of differential pressure rise can be easily reduced.
If the coverage is less than 30%, it is difficult to sufficiently prevent the catalyst from being blocked.
[0052]
In the present invention, the thickness, density, coating shape and the like of the coating layer are not particularly limited, but the thickness of the coating layer is preferably about 0.1 μm to 1 mm.
The catalyst as described above needs to have such strength that it does not collapse when packed in the reaction tower.
[0053]
Hydrodemetallation method of hydrocarbon oil The hydrodemetallation method of hydrocarbon oil according to the present invention hydrotreats hydrocarbon oil using the hydrodemetallation catalyst as described above.
[0054]
The hydrocarbon oil to be treated in the present invention is, for example, petroleum-based distillation residual oil (atmospheric pressure, reduced pressure), reduced-pressure light oil, cracked oil, history residual oil, coal liquefied oil, tar sand oil, shale oil oil, natural bitumen. Heavy oils such as men and crude oil.
[0055]
The hydrotreating of the hydrocarbon oil can be carried out by applying a conventionally known method without any particular limitation except that the hydrodemetallation catalyst according to the present invention as described above is used.
[0056]
The effect of the present invention can be manifested particularly when implemented in a fixed bed type. The reaction tower may be single-stage or multi-stage.
[0057]
The catalyst may be randomly packed in the hydrotreating apparatus, but the columnar catalyst having a large size can be arranged in an aligned manner with the end face directed in the flow direction of the reaction fluid.
Hydrodemetallation treatment
Temperature 200-550 ° C
Pressure 50-300kg / cm ²
Hydrogen circulation rate 500-2000 nm ³ / kl oil through the oil amount LHSV _0. 1~20hr ^-1
It is desirable to carry out under the following conditions.
[0058]
In the present invention, the hydrodemetallation reaction of hydrocarbon oil may be performed using only the hydrodemetallation catalyst as described above, or in combination with a conventional catalyst (a catalyst without a coating layer). Also good.
[0059]
When used in combination with a conventional catalyst, it may be used in a uniform mixed state throughout the reaction tower. However, as shown in FIG. 8, the main catalyst layer in the contact between the hydrocarbon oil and the hydrodemetallation catalyst is used. Preference is given to using the hydrodemetallation catalyst according to the invention.
[0060]
In FIG. 8, the reaction fluid 11 introduced from the upper part of the reaction tower 10 is first contacted with the hydrodemetallation catalyst 12 according to the present invention at the front stage in the reaction tower, and then is contacted with the conventional catalyst 13 at the rear stage. It is processed and extracted as 14 from the bottom of the reaction tower.
[0061]
As shown in FIG. 9, a reaction tower 20 using the hydrodemetallation catalyst 12 according to the present invention is attached upstream of the reaction tower 10 using a conventionally known catalyst 13, and the reaction fluid is previously reacted in the reaction tower 20. After the 11 is hydrodemetallated, the reaction fluid 11 may be hydrotreated in the reaction tower 10.
[0062]
As described above, when the hydrodemetallation catalyst according to the present invention is used in the initial contact between the reaction fluid and the hydrogenation catalyst, the pre-catalyst layer is unlikely to be clogged. Can be prolonged.
[0063]
【Example】
EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.
[0064]
[Example 1]
Catalyst preparation A catalyst was prepared as follows.
1. Support alumina raw material pseudoboehmite structure alumina (Versal 250 Alumina manufactured by LaRoche Industries INC. (LA, USA))
2. Molding (wheel type)
After adding water to the alumina raw material and kneading it sufficiently, it was molded by an extruder equipped with a mold capable of obtaining a catalyst having a shape as shown in FIG.
[0065]
The obtained alumina molded article was dried in air at 150 ° C. and then fired at 600 ° C. for 1 hour to obtain a cylindrical wheel-shaped alumina support.
[0066]
Cylindrical wheel shaped alumina carrier shape average outer diameter 8mm
Average length 9mm
Ribs 6 circle edge average thickness 1mm
Rib average thickness 1mm
3. Impregnation of active ingredients
(3-1) 258 parts by weight of ammonium molybdate (special grade made by Katayama Chemical) was dissolved little by little in 1000 parts by weight of pure water. In the resulting solution, 170 parts by weight of nickel nitrate (special grade made by Katayama Chemical) was dissolved little by little. At this time, aqueous ammonia was added as necessary to maintain the pH of the solution at 10. The obtained solution was used as an impregnation solution.
[0067]
(3-2) 330 g of a molded alumina carrier was immersed in the impregnation solution obtained above and held at room temperature under reduced pressure for 10 minutes for impregnation with the active metal component. Thereafter, the alumina support was quickly taken out from the impregnation solution and dried under air at 150 ° C. to obtain an alumina support impregnated with the active ingredient.
4). Formation of coating layer
(4-1) Preparation of coating layer forming slurry 100 parts by weight of frit (glaze) made of lead-silicon glass was added to 100 parts by weight of pure water, and pulverized and mixed with a ball mill. A solution in which 3 parts by weight of alcohol (polymerization degree 1100) was dissolved was added to obtain a slurry for forming a coating layer.
[0068]
Frit composition PbO 62% by weight
SiO ₂ 23% by weight
B ₂ O ₃ 9% by weight
Other 6% by weight
(4-2) The slurry obtained above is thinly brush-coated on the entire cylindrical side surface of the dry alumina carrier obtained in (3-2) and air-dried at 150 ° C. for 2 hours, as shown in FIG. Thus, an impregnated alumina carrier having a coating layer on the entire surface of the body was obtained.
[0069]
(4-3) The impregnated alumina support on which the coating layer obtained in (4-2) was formed was calcined at 600 ° C. for 30 minutes to obtain a Ni—Mo-alumina catalyst having a coating layer.
Catalyst average composition MoO ₃ 12.9 wt%
NiO 3.1 wt%
Al ₂ O ₃ carrier 74.0% by weight
Frit 10.0% by weight
Catalytic reaction test 1. Test equipment Fixed bed high-pressure flow reaction test equipment Hydrogen and feedstock are down-flow catalyst is irregularly packed reaction tube heating system is sand bath system Reaction conditions Reaction pressure 150kg / cm ² G
Reaction temperature 410 ° C
Hydrogen / raw oil ratio 700Nl / l
LHSV 0.5 hr ^-1
3. Reaction raw material: Middle East reduced pressure residual oil specific gravity (15 ° C) 1.02
Viscosity (100 ° C) 23cSt
Conradson Carbon 20.0% by weight
Asphaltene 7.6% by weight
Ni + V 174wtppm
Sulfur 3.8% by weight
4). Reaction Test Method After drying the catalyst in the reaction tube at 150 ° C. under a hydrogen flow, heavy light oil containing 1% by weight of dimethyl disulfide is supplied to the reaction tube together with hydrogen, and the reaction tube is heated to 250 ° C. at 15 ° C./hour. The catalyst was presulfided by increasing the temperature. Thereafter, the feed oil was switched to the raw material vacuum residue oil, and then the reaction tube temperature was raised to 410 ° C. at 1 ° C./hour, and this was maintained. The residual metal concentration in the hydrodemetallation-treated vacuum residue oil was measured by fluorescent X-ray analysis.
[0070]
As a result of the reaction test, the time-dependent change of the demetalization rate is shown in FIG. 10, and the time-dependent change of the fixed bed catalyst layer pressure loss ratio (P _T / P _O ) is shown in FIG.
Catalyst layer pressure loss [kg / cm ² ] at time T after _PT reaction start
P _O catalyst layer pressure loss at the start of the reaction after 1000 hours passed [kg / cm ^2]
[0071]
[Comparative Example 1]
In Example 1, the impregnated dry alumina carrier was calcined at 500 ° C. for 30 minutes to obtain a Ni—Mo—alumina catalyst.
[0072]
Catalyst average composition MoO ₃ 14.3% by weight
NiO 3.5 wt%
Al ₂ O ₃ 82.2% by weight
The results of testing in the same manner as in Example 1 are shown in FIGS.
[0073]
[Example 2]
Preparation of catalyst of Example 1 A catalyst having a coating layer was obtained in the same manner as in Example 1 except that the coating layer was provided on the half surface of the trunk as shown in FIG.
[0074]
The obtained catalyst is shown below.
Catalyst average composition MoO ₃ 13.6% by weight
NiO 3.3 wt%
Al ₂ O ₃ support 78.0% by weight
Frit 5.1% by weight
A catalytic reaction test was conducted in the same manner as in Example 1 except that the catalyst obtained above was used.
[0075]
FIG. 12 shows the change over time in the metal removal rate, and FIG. 13 shows the change over time in the fixed bed catalyst layer pressure loss ratio (P _T / P _O ). 12 and 13 also show the results of Comparative Example 1.
[0076]
[Example 3]
The catalyst having the coating layer obtained in Example 1 (see FIG. 2 for the wheel-type catalyst) and the catalyst (wheel-type catalyst) similar to Comparative Example 1 in which no coating layer was provided were mixed, and the same reaction tube The reaction test for 485 hours was conducted under the same conditions as in Example 1.
Regarding the catalyst having the coating layer after the reaction test, the metal accumulation state was analyzed with an X-ray microanalyzer. The accumulated metal concentration distribution is shown in the radial direction (1 mm thickness) of the outer periphery of the wheel catalyst.
FIG. 14 shows the vanadium accumulation concentration distribution (relative concentration), and FIG. 16 shows the iron accumulation concentration distribution (relative concentration).
[0077]
[Comparative Example 2]
FIG. 15 shows the vanadium accumulation concentration distribution (relative concentration) measured in the same manner as in Example 3 for the catalyst having no coating layer after the reaction test in Example 3.
[0078]
As a result of Example 3 and Comparative Example 2 as described above, in the catalyst of Example 3 (catalyst having a coating layer), as shown in FIG. High concentration of vanadium was observed, but no accumulation of vanadium was observed in the frit coating on the outer periphery of the edge and inside, confirming the effect of inactivation by frit. Further, as shown in FIG. 16, a large amount of iron accumulation layer is formed on the inner side of the edge portion not covered with frit, whereas iron accumulation is slightly on the outer surface of the edge portion that is frit coated. And the frit showed an outer surface deactivation effect.
On the other hand, in the catalyst of Comparative Example 2 without frit coating, a high concentration of vanadium was accumulated on the inner and outer surfaces of the catalyst edge as shown in FIG.
[0079]
【The invention's effect】
The hydrodemetallation catalyst for hydrocarbon oil according to the present invention can prevent an increase in catalyst layer pressure loss due to a clogging suppression effect during hydrodemetallation of hydrocarbon oil such as heavy oil. As a result, the catalyst below the blockage has sufficient activity and improved the conventional defect that the operation has to be stopped while maintaining a healthy state. It is possible to deposit high concentrations of contaminating heavy metals. In addition, it prevents precipitation of heavy heavy metals in heavy oil on the surface of the catalyst and concentrates the precipitation on the internal structure of the catalyst. At the same time, the extraction time is shortened.
[0080]
Furthermore, in the conventional demetallizing catalyst, from the viewpoint of preventing clogging, it was usual to lower the concentration of active components such as molybdenum to suppress the catalytic activity. Since the flow path can be secured, there is an advantage that the concentration of the active ingredient carried on the carrier can be increased. For this reason, even if there is a portion where the active surface decreases due to the coating layer, the desulfurization, denitrogenation activity and demetallizing function per unit catalyst amount are finally the functions when the conventional catalyst is filled or Further processing capacity can be secured sufficiently.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a Raschig ring-shaped hydrodemetallation catalyst having a coating layer on the entire body portion.
FIG. 2 is a perspective view showing a cylindrical hydrodemetallation catalyst having a plurality of through-holes and having a coating layer over the entire body.
FIG. 3 is a perspective view showing a cylindrical hydrodemetallation catalyst having a plurality of through-holes and having a coating layer on a part of a body portion.
FIG. 4 is a perspective view showing another example of a cylindrical hydrodemetallation catalyst having a plurality of through-holes and having a coating layer over the entire body portion.
FIG. 5 is a perspective view showing another example of a cylindrical hydrodemetallation catalyst having a plurality of through holes and having a coating layer on a part of a body portion.
FIG. 6 is a perspective view showing another example of a cylindrical hydrodemetallation catalyst having a plurality of through holes and having a coating layer on a part of a body portion.
Fig. 7 is a perspective view showing a honeycomb structure catalyst having a coating layer on the entire body portion.
FIG. 8 is a process diagram showing a preferred embodiment of the hydrodemetallation method for hydrocarbon oil according to the present invention.
FIG. 9 is another process diagram showing a preferred embodiment of the hydrodemetallation method for hydrocarbon oil according to the present invention.
FIG. 10 shows the change over time in the demetalization rate.
FIG. 11 shows a change with time of a fixed bed catalyst layer pressure loss ratio (P _T / P _O ).
FIG. 12 shows the change over time in the demetalization rate.
FIG. 13 shows a change with time of a fixed bed catalyst layer pressure loss ratio (P _T / P _O ).
FIG. 14 shows the results (vanadium accumulation relative concentration) of Example 3.
FIG. 15 shows the results of Comparative Example 2 (vanadium accumulation relative concentration).
FIG. 16 shows the results (iron accumulation relative concentration) of Example 3.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Catalyst 2 ... Coating layer 3 formed in a part of catalyst surface ... Support | carrier 3a with which catalyst component was carry | supported ... Projection part 4 ... Through-hole 10 ... Reaction tower 11 ... Reaction fluid 12 ... Hydrodehydration which concerns on this invention Metal catalyst 13 ... Conventional catalyst (catalyst without a coating layer)
14 ... Hydrotreated product 20 ... Reaction tower using hydrodemetallation catalyst according to the present invention

Claims (17)

A carrier and a catalyst component supported on the carrier;
It has a reaction flow path through which the reaction fluid flows inside the catalyst, and has a coating layer that is made of an inert substance that does not substantially have a metal removal function on at least a part of the catalyst surface and does not substantially allow the reaction fluid to permeate. A hydrodemetallation catalyst for hydrocarbon oils. The hydrodemetallation catalyst for hydrocarbon oil according to claim 1, wherein the catalyst is a cylindrical body having a single through hole as a reaction channel. The hydrodemetallation catalyst for hydrocarbon oil according to claim 1, wherein the catalyst is a cylindrical body having a plurality of through holes as a reaction channel. The hydrodemetallation catalyst for hydrocarbon oil according to claim 1, wherein the catalyst is a honeycomb structure having a plurality of through holes as a reaction channel. The hydrodemetallation catalyst for hydrocarbon oil according to claim 1, wherein the reaction channel has an equivalent diameter of 1 to 10 mm. 2. The hydrodemetallation catalyst for hydrocarbon oil according to claim 1, wherein the catalyst is a columnar body, and the coating layer is provided on the surface of the body of the column body. The hydrodemetallation catalyst for hydrocarbon oil according to claim 6, wherein the coating layer is provided on an end surface. ^{2. The} hydrodemetallation catalyst for hydrocarbon oil according to claim 1, wherein the coating layer has a specific surface area of 10 m ² / g or less. The hydrocarbon oil hydrogenation according to claim 1, wherein the coating layer is a dense layer that does not substantially permeate the reaction fluid and thereby does not contact the reaction fluid and the catalytically active sites. Demetallizing catalyst. 2. The hydrodemetallation catalyst for hydrocarbon oil according to claim 1, wherein the inert substance forming the coating layer is selected from glass, inert ceramics, and a metal inert under reaction conditions. The hydrodemetallation catalyst for hydrocarbon oil according to claim 10, wherein the glass is selected from low-temperature sintered glass, solder glass, and glaze. The hydrodemetallation catalyst for hydrocarbon oil according to claim 10, wherein the inert ceramic is selected from α-alumina, inert silica, cordierite, mullite and quartz. The hydrodemetallation catalyst for hydrocarbon oil according to claim 10, wherein the metal inert under the reaction conditions is selected from aluminum and stainless steel. The hydrodemetallation catalyst for hydrocarbon oil according to any one of claims 1 to 13, wherein the hydrodemetallation catalyst is a fixed bed filling catalyst. A hydrodemetallation method for a hydrocarbon oil, comprising hydrotreating the hydrocarbon oil in the presence of the hydrodemetallation catalyst for the hydrocarbon oil according to any one of claims 1 to 13. 16. The hydrodemetallation method for hydrocarbon oil according to claim 15, which is carried out in a fixed bed system. 17. The hydrocarbon according to claim 16, wherein the hydrodemetallation catalyst according to claim 1 is used for the uppermost catalyst layer in the contact between the hydrocarbon oil and the hydrodemetallation catalyst. Oil hydrodemetallation process.

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