A grading method and application of hydrogenation catalyst

Abstract

The present invention discloses a grading method and application of a hydrogenation catalyst. The method includes a hydrodemetallization reaction zone, wherein the hydrodemetallization reaction zone includes at least a first hydrodemetallization reaction zone and a second hydrodemetallization reaction zone which are sequentially connected in series along the direction of the logistics, and the catalyst loaded in the second hydrodemetallization reaction zone is a second hydrodemetallization catalyst, wherein at least one catalyst is loaded; and the active metal component of the second hydrodemetallization catalyst is distributed in a "protein type"; and the second hydrodemetallization catalyst adopts a specific loading method. The grading method is applied to the heavy oil hydrogenation reaction, which can reduce the deposition of metal impurities and carbon deposits on the catalyst, slow down the catalyst deactivation rate, improve the demetallization, desulfurization and residual carbon removal stability of the entire system, and extend the operation cycle of the catalyst.

Description

Technical Field

[0001] The invention belongs to the field of heavy oil hydroprocessing, and specifically relates to a hydrogenation catalyst grading method and application. The grading method is particularly suitable for the hydroprocessing process of residual oil with high metal impurities and Conradson carbon residue content. Background Art

[0002] As oil becomes increasingly difficult to extract and process, energy supply must strive to keep pace with demand. While the refining industry is dealing with the growing demand for various oil products, it is also facing stricter environmental regulations for road fuels and the need to reduce CO2 emissions from industrial sources. 2 Emissions. Heavy oil hydro-reforming can meet more stringent environmental regulations while increasing the production of light oil products. It is one of the effective technical solutions to help refiners meet the current market demand. Since heavy oil, especially residual oil, has a complex composition and contains a large amount of impurities, especially metals Ni, V, Fe, Ca, Na, etc., which have a poisoning effect on desulfurization catalysts and carbon removal catalysts, heavy oil hydro-processing generally adopts "catalyst combination loading technology" to gradually reduce the metal content in the feed to protect the downstream highly active hydro-desulfurization, denitrification / carbon removal catalysts, that is, use two or more catalysts with different functions. The functional catalysts include hydrogenation protectors, hydro-demetallization catalysts, hydro-desulfurization catalysts, hydro-denitrification / carbon removal catalysts, etc. The conventional catalyst grading loading principle is: along the direction of the raw material flow, the content of the active component of the catalyst gradually increases, the pore size gradually decreases, the particle size gradually decreases, and the porosity gradually decreases.

[0003] US4447314 proposes a dual catalyst system for residual oil hydroprocessing. The first catalyst is a macroporous catalyst and the second catalyst is a small pore catalyst. The raw material first passes through the first catalyst and then sequentially passes through the second catalyst to achieve demetallization and desulfurization of the residual oil.

[0004] US4306964 discloses a method for demetallizing residual oil. The method is to contact the oil successively with three or more stages of catalysts having successively decreasing average pore diameters and successively increasing specific surface areas, wherein the first stage catalyst has at least 60% of its pore diameters being The pore volume of pores, up to 5% of the pore size is larger than The pore volume of the pores and the specific surface area are up to 120m 2 / g, the second stage catalyst has at least 40% pore size The pore volume of the pores and the specific surface area are 120-180m 2 / g, the last stage catalyst has at least 60% pore size The pore volume of the pores and the specific surface area are at least 200m 2 / g.

[0005] CN1197105A discloses a method for hydrotreating hydrocarbon raw materials containing metal pollutants. The method is to contact the raw materials with one or more catalyst beds of the first catalyst, the second catalyst, and the third catalyst in the presence of hydrogen. The properties and functions of the catalysts in each bed are different. In fact, along the direction of logistics, the catalyst activity gradually increases and the pore size gradually decreases. It is a conventional hydrotreating process of first demetallization, then desulfurization, and finally denitrification. The method can reduce the metal content in the feed step by step to protect the downstream highly active hydrodesulfurization and denitrification catalysts. Its disadvantages are that the temperature rise in the lower part of the reactor is high, the hydrogen purity is low, and the deposition of metal impurities and carbon deposits in the lower part of the reactor is serious, which will restrict the long-term operation of the heavy oil hydrogenation unit. Especially when processing inferior residual oil with high metal and Conradson carbon content, it is very easy to cause orifice blockage, resulting in rapid decay of catalyst activity and poor stability.

[0006] CN1393518A discloses a grading method for residual oil hydroprocessing catalyst. The method is to divide the desulfurization or denitrification reaction zone into two or more catalyst beds, and add a mixed transition bed between the two beds. The catalyst grading method of the desulfurization reaction zone or the denitrification reaction zone is different from the commonly used grading method. The principle of gradually reducing the activity of the catalyst along the logistics direction is adopted to make the temperature rise of each catalyst bed more stable. Compared with the traditional method, the temperature rise of each catalyst bed in this method is easy to control, no hot spots will appear in the reaction zone, and the hydrogen consumption is greatly reduced. However, it fails to solve the problem that the excessive deposition of metal impurities and carbon deposits in the lower part of the reactor leads to rapid decay of catalyst activity. Summary of the invention

[0007] In view of the shortcomings of the prior art, the present invention provides a grading method and application of a hydrogenation catalyst. The grading method of the present invention is applied to heavy oil hydrogenation reaction, which can reduce the deposition of metal impurities and carbon deposits on the catalyst, slow down the deactivation rate of the catalyst, improve the demetallization, desulfurization and residual carbon removal stability of the entire system, and extend the operation cycle of the catalyst.

[0008] The present invention provides a grading method for a hydrogenation catalyst, wherein the method comprises a hydrodemetallization reaction zone, wherein the hydrodemetallization reaction zone comprises at least a first hydrodemetallization reaction zone and a second hydrodemetallization reaction zone which are sequentially connected in series along a logistics direction, wherein the catalyst loaded in the second hydrodemetallization reaction zone is a second hydrodemetallization catalyst, wherein at least one catalyst is loaded; and the active metal component of the second hydrodemetallization catalyst is distributed in a "protein type"; and the particle size, pore size, porosity and active metal content of any second hydrodemetallization catalyst are respectively greater than the particle size, pore size, porosity and active metal content of the upstream catalyst adjacent thereto.

[0009] According to the present invention, the second hydrodemetallization catalyst is loaded in the direction of the reactant flow, with the particle size increasing from small to large, the pore size increasing from small to large, the porosity increasing from small to large, and the active metal content increasing from low to high.

[0010] According to the present invention, the loading method of the second hydrodemetallization catalyst means that relative to the first hydrodemetallization catalyst loaded in the first hydrodemetallization reaction zone adjacent to the second hydrodemetallization reaction zone, the loading method of each second hydrodemetallization catalyst loaded in the second hydrodemetallization reaction zone is along the direction of the reactant flow, the particle size is from small to large, the pore size is from small to large, the porosity is from small to large, and the active metal content is from low to high. That is, the particle size, pore size, porosity, and active metal content of any second hydrodemetallization catalyst are respectively greater than the particle size, pore size, porosity, and active metal content of the upstream catalyst adjacent to it.

[0011] According to the present invention, the active metal component is distributed in an "egg-like" manner: from the outer surface to the center of the catalyst particle, it is generally divided into three layers, namely, the outer "eggshell", the middle "egg-white" and the inner "egg-yolk". Among them, the outer "egg-shell" contains no or a small amount of metal, which can effectively solve the problem that the pores are easily blocked by metal impurities and cause permanent deactivation; the "egg-white" of the middle layer of the catalyst contains a relatively high active metal; and the "egg-yolk" inside the catalyst contains no or a small amount of metal components. This design is based on the fact that a small amount of metal impurities are deposited inside the catalyst after industrial use. The reason is that the large particle size of the catalyst leads to a long diffusion path for the reaction molecules, and it is difficult to diffuse into the internal "egg-yolk" of the catalyst. The catalyst design with an "egg-like" distribution of active metal components can avoid the waste of internal active centers caused by the inability of impurities to diffuse into the interior of the catalyst particles. It can reduce the deposition of metal impurities at the pores of the catalyst while improving the utilization rate of the active metal of the catalyst.

[0012] According to the present invention, the first hydrodemetallization reaction zone is sequentially loaded with at least one hydrogenation protection catalyst and at least one first hydrodemetallization catalyst along the logistics direction.

[0013] According to the present invention, the hydrogenation protection catalyst is preferably a combination of multiple hydrogenation protection catalysts, preferably 2 to 4 types.

[0014] According to the present invention, preferably, the first hydrodemetallization reaction zone is loaded with 2 to 4 first hydrodemetallization catalysts.

[0015] According to the present invention, preferably, the second hydrodemetallization reaction zone is loaded with 2 to 4 types of second hydrodemetallization catalysts. Preferably, the loading volume of each catalyst accounts for at least 5% of the total volume of the catalyst loaded in the second hydrodemetallization reaction zone, preferably 10% to 70%, and more preferably 20% to 60%.

[0016] According to the present invention, the catalyst (i.e., the hydrogenation protection catalyst and the first hydrodemetallization catalyst) in the first hydrodemetallization reaction zone is loaded in a conventional manner and can be loaded according to conventional catalyst grading principles. Along the logistics direction, the particle size of the catalyst is from large to small, the pore size is from large to small, the porosity is from large to small, and the active metal content is from low to high.

[0017] According to the present invention, based on the total volume of the catalyst loaded in the hydrodemetallization reaction zone, the hydrogenation protection catalyst accounts for 10% to 60% of the volume, preferably 20% to 50% of the volume; the first hydrodemetallization catalyst accounts for 10% to 50% of the volume, preferably 30% to 50% of the volume; the second hydrodemetallization catalyst accounts for 10% to 50% of the volume, preferably 20% to 30% of the volume.

[0018] According to the present invention, the composition of the hydrogenation protection catalyst includes: a porous oxide as a carrier, and a VIB group metal and / or a VIII group metal as an active metal component. Based on the mass of the hydrogenation protection catalyst, the content of the active metal in the oxide is 0wt% to 10wt%, and the content of the carrier is 90wt% to 100wt%. The porous oxide is preferably alumina. The VIB group metal is at least one selected from Mo and W; the VIII group metal is at least one selected from Co and Ni. Preferably, one or more of P, B, Si, F, Ti and Zr can be added as an additive.

[0019] According to the present invention, the composition of the first hydrodemetallization catalyst includes: a porous oxide as a carrier, and a VIB group metal and / or a VIII group metal as an active metal component. Based on the mass of the first hydrodemetallization catalyst, the content of the active metal in terms of oxide is 5wt% to 12wt%, and the content of the carrier is 88wt% to 95wt%. The porous oxide is preferably alumina. The VIB group metal is at least one selected from Mo and W; the VIII group metal is at least one selected from Co and Ni. Preferably, one or more of P, B, Si, F, Ti and Zr can be added as an additive.

[0020] According to the present invention, the composition of the second hydrodemetallization catalyst includes: a porous oxide as a carrier, and a VIB group metal and / or a VIII group metal as an active metal component. Based on the mass of the second hydrodemetallization catalyst, the content of the active metal in terms of oxide is 7wt% to 15wt%, and the content of the carrier is 85wt% to 93wt%. The porous oxide is preferably alumina. The VIB group metal is at least one selected from Mo and W; the VIII group metal is at least one selected from Co and Ni. Preferably, one or more of P, B, Si, F, Ti and Zr can be added as an additive.

[0021] According to the present invention, the active metal content of any second hydrodemetallization catalyst is higher than the active metal content of the adjacent upstream catalyst, calculated as oxide; preferably, the active metal weight content of any second hydrodemetallization catalyst is 0.8 to 4.5 percentage points higher than the active metal weight content of the adjacent upstream catalyst, calculated as oxide.

[0022] According to the present invention, preferably, the active metals in the second hydrodemetallization catalyst include Mo and Ni; and the active metals in the first hydrodemetallization catalyst adjacent to the second hydrodemetallization zone include Mo and Ni.

[0023] According to the present invention, further, the composition of the first hydrodemetallization catalyst includes, based on the mass of the first hydrodemetallization catalyst, an aluminum oxide content of 88wt% to 95wt%, calculated as oxide, a Mo content of 3.8wt% to 10wt%, and a Ni content of 1.2wt% to 2wt%; the composition of the second hydrodemetallization catalyst includes, based on the mass of the second hydrodemetallization catalyst, an aluminum oxide content of 85wt% to 93wt%, calculated as oxide, a Mo content of 5.5wt% to 13.5wt%, and a Ni content of 1.5wt% to 3.5wt%.

[0024] According to the present invention, preferably, calculated as oxides, the Mo weight content of any second hydrodemetallization catalyst is 0.5 to 3 percentage points higher than that of its adjacent upstream catalyst, preferably 0.7 to 2.5 percentage points higher, and the Ni weight content is 0.3 to 1.5 percentage points higher, preferably 0.3 to 1.0 percentage points higher.

[0025] According to the present invention, the particle size of the hydrogenation protection catalyst is 1.5 to 10 mm, the pore size is 10 to 100 nm, and the porosity is 45.0% to 60.0%.

[0026] According to the present invention, the particle size of the first hydrodemetallization catalyst is 1.0 to 2.5 mm, the pore size is 10 to 30 nm, and the porosity is 42.0% to 46.0%.

[0027] According to the present invention, the particle size of the second hydrodemetallization catalyst is 1.5 to 2.7 mm, the pore size is 15 to 33 nm, and the porosity is 44.0% to 47.0%.

[0028] According to the present invention, the particle size of any second hydrodemetallization catalyst is larger than the particle size of the adjacent upstream catalyst. Preferably, the particle sizes of the two adjacent catalysts differ by at least 0.2 mm, preferably 0.3 to 1.0 mm.

[0029] According to the present invention, the pore size of any second hydrodemetallization catalyst is larger than the pore size of the adjacent upstream catalyst. Preferably, the pore sizes of the two adjacent catalysts differ by at least 1.0 nm, preferably 1.2 nm to 5.0 nm.

[0030] According to the present invention, the porosity of any second hydrodemetallization catalyst is greater than the porosity of the adjacent upstream catalyst. Preferably, the porosity of the two adjacent catalysts differs by at least 0.3 percentage points, preferably 0.5 to 3 percentage points.

[0031] According to the present invention, a hydrodesulfurization reaction zone may be further included, wherein at least one hydrodesulfurization catalyst is loaded. In the direction of the flow, the hydrodesulfurization reaction zone is located downstream of the hydrodemetallization reaction zone.

[0032] According to the present invention, preferably, 2 to 3 hydrodesulfurization catalysts are loaded in the hydrodesulfurization reaction zone.

[0033] According to the present invention, preferably, a hydrodemetallization catalyst may be loaded upstream of the hydrodesulfurization catalyst in the hydrodesulfurization reaction zone. The function of loading the hydrodemetallization catalyst is to achieve a better activity transition.

[0034] According to the present invention, preferably, a hydrodecarbonization reaction zone may be further included, which is located downstream of the hydrodesulfurization reaction zone along the logistics direction. The hydrodecarbonization reaction zone is loaded with at least one hydrodecarbonization catalyst.

[0035] According to the present invention, the hydrodesulfurization reaction zone and the hydrodecarbonization reaction zone are loaded with catalysts according to conventional catalyst grading principles, that is, along the logistics direction, the catalyst particle size is from large to small, the pore size is from large to small, the porosity is from large to small, and the active metal content is from low to high.

[0036] According to the present invention, the compositions of the hydrodesulfurization catalyst and the hydroremoval of carbon residue catalyst independently include: a porous oxide as a carrier, and a VIB group metal and / or a VIII group metal as an active metal component. Based on the mass of the catalyst, the content of the active metal in the oxide is 15wt% to 25wt%, and the content of the carrier is 75wt% to 85wt%. The porous oxide is preferably alumina. The VIB group metal is at least one selected from Mo and W; the VIII group metal is at least one selected from Co and Ni. Preferably, one or more of P, B, Si, F, Ti and Zr can be added as an additive.

[0037] According to the present invention, the number of reactors in the grading method may be 2 to 5. Preferably, the first hydrodemetallization reaction zone and the second hydrodemetallization reaction zone are arranged in the same reactor, and the hydrodesulfurization reaction zone and the hydrodecarbonization reaction zone are arranged in other reactors.

[0038] According to the present invention, the volume ratio of the catalyst loaded in the hydrodemetallization reaction zone, the hydrodesulfurization reaction zone, and the hydrodecarbonization reaction zone can be set according to conventional methods, wherein the catalyst loaded in the hydrodemetallization reaction zone accounts for 20% to 50% of the total loaded volume.

[0039] According to the present invention, the catalyst in the grading method can be prepared by conventional methods in the prior art or commercial catalysts. Preferably, the first hydrodemetallization catalyst is a commercial catalyst, and the second hydrodemetallization catalyst with a "protein-type" distribution of active metal components can be first prepared by the method described in CN101927169A, and then prepared by a deionized water leaching method.

[0040] According to the present invention, the catalyst in each reactor is generally loaded by bag-type loading or dense-phase loading, and the loading methods of the catalyst are all conventional loading methods in the art.

[0041] The second aspect of the present invention provides an application of the above-mentioned hydrogenation catalyst grading method in heavy oil hydrogenation reaction.

[0042] According to the present invention, in the application, the operating conditions of each reactor are independently: average reaction temperature 330°C to 450°C, preferably 350°C to 430°C, more preferably 360°C to 420°C; reaction hydrogen partial pressure 8.0MPa to 20.0MPa, preferably 10.0MPa to 18.0MPa, more preferably 12.0MPa to 18.0MPa; liquid hourly volume space velocity 0.15h -1 ~3.0h -1 , preferably 0.2h -1 ~2.0h -1 , more preferably 0.2h -1 ~1.2h -1 ; The volume ratio of hydrogen to oil is 300 to 1500, preferably 400 to 1300, and more preferably 500 to 1000.

[0043] Compared with the prior art, the present invention has the following beneficial effects:

[0044] 1. In the present invention, the grading method of the hydrogenation catalyst, wherein the method includes a hydrodemetallization reaction zone, the hydrodemetallization reaction zone includes at least a first hydrodemetallization reaction zone and a second hydrodemetallization reaction zone connected in series in the direction of the logistics, the catalyst loaded in the second hydrodemetallization reaction zone is a second hydrodemetallization catalyst, wherein at least one catalyst is loaded; and the active metal component of the second hydrodemetallization catalyst is distributed in a "protein type"; the particle size, pore size, porosity, and active metal content of any second hydrodemetallization catalyst are respectively greater than the particle size, pore size, porosity, and active metal content of the upstream catalyst adjacent thereto. The deactivation of the hydrogenation catalyst is mainly caused by the deposition of metal impurities and carbon deposition. The residual oil hydrogenation reaction is an exothermic reaction. Along the direction of the logistics, the temperature of the reaction zone gradually increases, and the non-ideal components increase, and the hydrogen concentration decreases, resulting in a high temperature at the bottom of the reactor and a low hydrogen concentration. The carbon deposition reaction of the catalyst is very sensitive to temperature and hydrogen concentration, which causes the carbon deposition of the catalyst in the lower part of the reactor to be usually more serious than that in the upper part, and the catalyst bed is prone to coking, especially for the catalyst bed with small pore size in the lower part of the reactor. At the same time, due to the small particle size, pore size and porosity, the catalyst pores are easily blocked with the continuous deposition of metal impurities, the catalyst deactivates quickly, and the stability is poor. In the present invention, the pore size and porosity of the second hydrodemetallization catalyst near the lower part of the reactor are greater than those of the upstream catalyst, and the loading order of the second hydrodemetallization catalyst is loaded in reverse order, the catalyst pores are not easy to be blocked, the catalyst deactivation rate is slow, and the stability is better. At the same time, compared with the conventional grading method, the active metal components of this section of the catalyst are distributed in a "protein type", which can avoid the waste of internal active centers due to the inability of impurities in the raw materials to diffuse into the interior of the catalyst particles. It can reduce the deposition of metal impurities at the catalyst pores while improving the utilization rate of the active metals of the catalyst, improving the hydrogenation performance, and fully ensuring the reaction activity of the entire catalyst system. The catalyst grading combination of the present invention can give full play to the role of the catalyst in the lower area of ​​the reactor, reduce the deposition of metal impurities and carbon deposits on the catalyst, slow down the catalyst deactivation rate, improve the demetallization, desulfurization and residual carbon removal stability of the entire system, and extend the operation cycle of the catalyst.

[0045] 2. In the present invention, the grading method is suitable for heavy oil hydrogenation reaction. The grading method can reduce the deposition of metal impurities and carbon deposits on the catalyst, slow down the deactivation rate of the catalyst, improve the demetallization, desulfurization and carbon removal stability of the entire system, and extend the operation cycle of the catalyst. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 and Figure 2 Schematic diagram of the “protein-type” distribution of active metal components of the second hydrodemetallization catalyst. DETAILED DESCRIPTION

[0047] The present invention will be further described below by way of examples, but the protection scope of the present invention is not limited by the examples.

[0048] In the present invention, the particle size of the catalyst is measured using a vernier caliper.

[0049] In the present invention, the aperture is a variable aperture, which can be made of low temperature N 2 Adsorption method: the instrument is ASAP2420 fully automatic physical adsorption instrument.

[0050] In each example of the present invention, the hydrogenation protection catalyst is FZC-11A and FZC-12B. The first hydrodemetallization catalyst is FZC-103E and FZC-201, and the second hydrodemetallization catalyst is CB-1, CB-2, and FZC-28. The hydrodemetallization catalyst is FZC-204A. The hydrodesulfurization catalyst is FZC-33. The hydrodecarbonation catalyst is FZC-41. Among the above catalysts, CB-1 and CB-2 are self-made second hydrodemetallization catalysts, and the remaining catalysts are a full range of residual oil hydrotreating catalysts developed by Dalian Petrochemical Research Institute.

[0051] In each example of the present invention, the preparation method of CB-1 is as follows: first, it is prepared according to the method described in CN101927169A. Take 150g of alumina carrier (FZC-28A carrier of Dalian Petrochemical Research Institute, water absorption rate 1.10mL / g, particle size 1.6mm, pore size 17.6nm, porosity 44.7%), spray 30mL of 10wt% ammonia solution, and during the spraying process, uniformly drip 60mL of 8.0g ammonium molybdate (MoO 3 82wt%) and 4.8g nickel nitrate (NiO content 25wt%) in an ammonia solution (ammonia content 15wt%) were added to the impregnation solution and stirred evenly. After the impregnation was completed, 30mL of 5.0g ammonium molybdate (MoO 3 After spraying 20 mL of an ammonia solution (ammonia content 15 wt%) containing 8.2 g of ammonium molybdate (MoO content 82 wt%) and 3.2 g of nickel nitrate (NiO content 25 wt%), 45 mL of an ammonia solution (ammonia content 15 wt%) containing 8.2 g of ammonium molybdate (MoO content 25 wt%) was uniformly dripped into the solution. 3 Add 8g of nickel nitrate (NiO content 82wt%) and 8g of ammonia solution (ammonia content 15wt%) into the impregnation solution and stir evenly, dripping and impregnating. After spraying, homogenize for 20 minutes.

[0052] The homogenized sample was immersed in deionized water for 3 to 5 seconds, taken out and dried at 120°C for 10 hours, and then calcined in air at 500°C for 3 hours to obtain the catalyst. 3 The content is 9.0wt%, the NiO content is 2.2wt%, and the pore diameter is 17.1nm.

[0053] In each example of the present invention, the preparation method of CB-2 catalyst is as follows:

[0054] First, prepare according to the method described in CN101927169A. Take 150g of alumina carrier (Dalian Petrochemical Research Institute FZC-103E carrier, water absorption rate 1.14mL / g, particle size 1.9mm, pore size 21.6nm, porosity 45.4%), spray 30mL of 10wt% ammonia solution, and during the spraying process, uniformly drip 60mL of 8.5g ammonium molybdate (MoO 3 82wt%) and 5.0g nickel nitrate (NiO content 25wt%) in an ammonia solution (ammonia content 15wt%) were added to the impregnation solution and stirred evenly. After the impregnation was completed, 30mL of 6.0g ammonium molybdate (MoO 3 After spraying 20 mL of an ammonia solution (ammonia content 15 wt%) containing 82 wt % of nickel nitrate (NiO content 25 wt %), 45 mL of an ammonia solution containing 9.0 g of ammonium molybdate (MoO 3 Add 8.5g of nickel nitrate (NiO content 25wt%) and 82wt% of ammonia solution (ammonia content 15wt%) into the impregnation solution and stir evenly, dripping and impregnating. After spraying, homogenize for 20 minutes.

[0055] The homogenized sample was immersed in deionized water for 3 to 5 seconds, taken out and dried at 120°C for 10 hours, and then calcined in air at 500°C for 3 hours to obtain the catalyst. 3 The content is 9.7wt%, the NiO content is 2.5wt%, and the pore diameter is 21.1nm.

[0056] The schematic diagram of the "protein type" distribution of the active metal components of the prepared catalysts CB-1 and CB-2 is shown in Figure 1 and Figure 2 shown.

[0057] In each example of the present invention, the main physical and chemical properties of the catalyst are shown in Tables 1 to 3. The main properties of the feedstock oil for evaluating the catalyst system are listed in Table 4. The evaluation conditions of the graded catalyst are shown in Table 5. The relative removal rate evaluation results are shown in Tables 6 and 7.

[0058] In each example of the present invention, the second hydrodemetallization catalyst is loaded in the first reactor in such a manner that, along the direction of the flow, the particle size of the catalyst increases from small to large, the pore size increases from small to large, the porosity increases from small to large, and the active metal content transitions from low to high. The particle size, pore size, porosity, and active metal component content of any second hydrodemetallization catalyst are respectively greater than the particle size, pore size, porosity, and active metal component content of the adjacent upstream catalyst.

[0059] In each example of the present invention, the test was conducted on three reactors connected in series. Along the logistics direction, they were first reactor, second reactor, and third reactor. The catalyst loading volume ratio of the first reactor, second reactor, and third reactor was 30:35:35. Among them, the catalyst loading method of the second reactor and the third reactor was the same, and the catalyst loading method of the first reactor was different.

[0060] Example 1

[0061] The test was conducted on a test rig with three 3-liter reactors. The catalyst loading conditions of each reactor were:

[0062] The first reactor is the first hydrodemetallization reaction zone and the second hydrodemetallization reaction zone from top to bottom, wherein the first hydrodemetallization reaction zone is sequentially loaded with FZC-11A, FZC-12B, FZC-103E, and FZC-201 from top to bottom, and the second hydrodemetallization reaction zone is loaded with CB-1, and the loading ratio (V) of the above catalysts is: 1:2.5:2:2.5:2; the second reactor is loaded with FZC-204A and FZC-33 from top to bottom, and the loading volume ratio is 1.5:1; the third reactor is loaded with catalyst FZC-41. The loading volume ratio of the first reactor, the second reactor, and the third reactor catalyst is 30:35:35. The main properties of the catalysts are shown in Table 1.

[0063] The application of the above hydroprocessing catalyst grading method in the residual oil hydrogenation reaction was evaluated. The test results of 400 hours, 1000 hours and 3000 hours of stable operation with residual oil are shown in Table 6.

[0064] Table 1 Main physicochemical properties of catalysts

[0065]

[0066] Example 2

[0067] This example shows a combined process for preparing a catalyst grading system. The test was carried out in a test device with three 3-liter reactors.

[0068] The catalyst loading conditions of each reactor are as follows:

[0069] The first reactor is composed of the first hydrodemetallization reaction zone and the second hydrodemetallization reaction zone from top to bottom, wherein the first hydrodemetallization reaction zone is sequentially loaded with FZC-11A, FZC-12B, FZC-103E, and FZC-201 from top to bottom, and the second hydrodemetallization reaction zone is loaded with CB-1, and the loading ratio (V) of the above catalysts is: 1.0:2.0:2.0:2.0:3.0. The catalyst loading method of the second reactor and the third reactor is the same as that of Example 1. The loading volume ratio of the catalysts of the first reactor, the second reactor, and the third reactor is the same as that of Example 1. The main properties of the catalysts are shown in Table 1.

[0070] The application of the above hydroprocessing catalyst grading method in the residual oil hydrogenation reaction was evaluated. The test results of 400 hours, 1000 hours and 3000 hours of stable operation with residual oil are shown in Table 7.

[0071] Example 3

[0072] This example shows a combined process for preparing a catalyst grading system, which was tested in a test device with three 3-liter reactors.

[0073] The catalyst loading conditions of each reactor are as follows:

[0074] The first reactor is composed of the first hydrodemetallization reaction zone and the second hydrodemetallization reaction zone from top to bottom, wherein the first hydrodemetallization reaction zone is sequentially loaded with FZC-11A, FZC-12B, FZC-103E, and FZC-201 from top to bottom, and the second hydrodemetallization reaction zone is sequentially loaded with CB-1 and CB-2 from top to bottom, and the loading ratio (V) of the above catalysts is: 1:2.5:2:2.5:1:1. The catalyst loading method of the second reactor and the third reactor is the same as that of Example 1. The loading volume ratio of the catalysts of the first reactor, the second reactor, and the third reactor is the same as that of Example 1. The main properties of the catalysts are shown in Table 2.

[0075] Table 2 Main physical and chemical properties of catalysts

[0076]

[0077] The application of the above hydroprocessing catalyst grading method in the residual oil hydrogenation reaction was evaluated. The test results of 400 hours, 1000 hours and 3000 hours of stable operation with residual oil are shown in Table 6.

[0078] Example 4

[0079] This example shows a combined process for preparing a catalyst grading system, which was tested in a test device with three 3-liter reactors.

[0080] The catalyst loading conditions of each reactor are as follows:

[0081] The first reactor is composed of the first hydrodemetallization reaction zone and the second hydrodemetallization reaction zone from top to bottom, wherein the first hydrodemetallization reaction zone is sequentially loaded with FZC-11A, FZC-12B, FZC-103E, and FZC-201, and the second hydrodemetallization reaction zone is sequentially loaded with CB-1 and CB-2 from top to bottom, and the loading ratio (V) of the above catalysts is: 1.0:2.0:2.0:2.0:2.0:1.0. The catalyst loading method of the second reactor and the third reactor is the same as that of Example 1. The loading volume ratio of the catalysts of the first reactor, the second reactor, and the third reactor is the same as that of Example 1. The main properties of the catalysts are shown in Table 2.

[0082] The application of the above hydroprocessing catalyst grading method in the residual oil hydrogenation reaction was evaluated. The test results of 400 hours, 1000 hours and 3000 hours of stable operation with residual oil are shown in Table 7.

[0083] Comparative Example 1

[0084] The tests were carried out in a pilot plant with three 3-liter reactors.

[0085] The catalyst loading conditions of each reactor are as follows:

[0086] The first reactor is composed of the first hydrodemetallization reaction zone and the second hydrodemetallization reaction zone from top to bottom, wherein the first hydrodemetallization reaction zone is sequentially loaded with FZC-11A, FZC-12B, FZC-103E, and FZC-201 from top to bottom, and the second hydrodemetallization reaction zone is loaded with FZC-28, and the loading ratio (V) of the above catalysts is: 1:2.5:2:2.5:2; the catalyst loading method of the second reactor and the third reactor is the same as that of Example 1. The loading volume ratio of the catalysts of the first reactor, the second reactor, and the third reactor is the same as that of Example 1. The main properties of the catalysts are shown in Table 3.

[0087] Table 3 Main physicochemical properties of catalysts

[0088]

[0089] The application of the above hydroprocessing catalyst grading method in the residual oil hydrogenation reaction was evaluated. The test results of 400 hours, 1000 hours and 3000 hours of stable operation with residual oil are shown in Table 6.

[0090] Comparative Example 2

[0091] This example shows a combined process for preparing a catalyst grading system. The test was carried out in a test device with three 3-liter reactors.

[0092] The catalyst loading conditions of each reactor are as follows:

[0093] The first reactor is composed of the first hydrodemetallization reaction zone and the second hydrodemetallization reaction zone from top to bottom, wherein the first hydrodemetallization reaction zone is sequentially loaded with FZC-11A, FZC-12B, FZC-103E, and FZC-201 from top to bottom, and the second hydrodemetallization reaction zone is loaded with FZC-28, and the loading ratio (V) of the above catalysts is: 1.0:2.0:2.0:2.0:3.0; the catalyst loading method of the second reactor and the third reactor is the same as that of Example 1. The loading volume ratio of the catalysts of the first reactor, the second reactor, and the third reactor is the same as that of Example 1. The main properties of the catalysts are shown in Table 3.

[0094] The application of the above hydroprocessing catalyst grading method in the residual oil hydrogenation reaction was evaluated. The test results of 400 hours, 1000 hours and 3000 hours of stable operation with residual oil are shown in Table 7.

[0095] Table 4 Raw oil properties

[0096] Raw oil properties Slag in the sand <![CDATA[Density (20 °C) / kg·m -3 > 983.5 <![CDATA[Ni+V / μg·g -1 ]]> 108.8 S, wt% 3.3 CCR, wt% 14.5

[0097] Table 5 Hydrogenation operating conditions for each example

[0098] One counter Second anti Three anti Average reaction temperature, °C 370 375 385 Reaction hydrogen partial pressure, MPa 15.7 15.7 15.7 <![CDATA[Liquid hourly space velocity, h -1 > 0.22 0.22 0.22 Hydrogen to oil volume ratio 850 850 850

[0099] Table 6 Comparison of reaction performance between examples and comparative examples

[0100]

[0101] Table 7 Comparison of reaction performance between examples and comparative examples

[0102]

[0103] It can be seen from Table 4 that the initial activity of the catalysts of Examples 1, 3 and Comparative Example 1 at 400h is roughly equivalent. With the extension of the operating time, the demetallization rate and the residual carbon removal rate of Examples 1 and 3 are higher than those of the comparative catalyst combination; and the degree of attenuation of the removal rate is less than that of the comparative example. The desulfurization rate is roughly equivalent to that of the comparative example. In comparison, Example 3 adopts a combination of two demetallization catalysts, and its demetallization and residual carbon removal reaction performance is more advantageous. In general, it is explained that the catalyst combination method of the present invention improves the activity and stability of the entire system.

[0104] As can be seen from Table 5, the reaction performance of Example 2 and Example 4 shows similar rules to the combination of Example 1 and Example 3 given in Table 4. The initial activity of the catalysts of Example 2 and 4 at 400h is roughly equivalent to that of Comparative Example 2. With the extension of the operation time, the demetallization rate and residual carbon removal rate of Examples 2 and 4 are higher than that of the catalyst combination of Comparative Example 2; and the degree of attenuation of the removal rate is less than that of the Comparative Example. The desulfurization rate is roughly equivalent to that of the Comparative Example. In general, the catalyst combination method of the present invention improves the stability of the entire system.

Claims

1. A grading method for a hydrogenation catalyst, wherein: The method comprises a hydrodemetallization reaction zone, wherein the hydrodemetallization reaction zone comprises at least a first hydrodemetallization reaction zone and a second hydrodemetallization reaction zone which are sequentially connected in series along a logistics direction, wherein the catalyst loaded in the second hydrodemetallization reaction zone is a second hydrodemetallization catalyst, wherein at least one catalyst is loaded; and the active metal component of the second hydrodemetallization catalyst is distributed in a "protein type" manner; the particle size, pore size, porosity, and active metal content of any second hydrodemetallization catalyst are respectively greater than the particle size, pore size, porosity, and active metal content of the upstream catalyst adjacent thereto; The "egg white type" distribution is as follows: the outer "egg shell" contains no or a small amount of metal, the middle "egg white" contains a relatively high active metal; and the inner "egg yolk" of the catalyst contains no or a small amount of metal components.

2. The grading method according to claim 1, characterized in that: The first hydrodemetallization reaction zone is sequentially loaded with at least one hydroprotection catalyst and at least one first hydrodemetallization catalyst along the logistics direction.

3. The grading method according to claim 2, characterized in that: Based on the total volume of the catalyst loaded in the hydrodemetallization reaction zone, the hydroprotection catalyst accounts for 10% to 60% of the volume; the first hydrodemetallization catalyst accounts for 10% to 50% of the volume; and the second hydrodemetallization catalyst accounts for 10% to 50% of the volume.

4. The grading method according to claim 3, characterized in that: Based on the total volume of the catalyst loaded in the hydrodemetallization reaction zone, the hydroprotection catalyst accounts for 20% to 50% of the volume; the first hydrodemetallization catalyst accounts for 30% to 50% of the volume; and the second hydrodemetallization catalyst accounts for 20% to 30% of the volume.

5. The grading method according to claim 1, characterized in that: The second hydrodemetallization reaction zone is loaded with 2 to 4 types of second hydrodemetallization catalysts.

6. The grading method according to claim 2, characterized in that: The composition of the first hydrodemetallization catalyst comprises: a porous oxide as a carrier and a VIB group metal and / or a VIII group metal as an active metal component; the first hydrodemetallization catalyst, based on the mass of the first hydrodemetallization catalyst, has an active metal content of 5wt% to 12wt% in terms of oxide and an active metal content of 88wt% to 95wt% in terms of carrier; The composition of the second hydrodemetallization catalyst includes: a porous oxide as a carrier and a VIB group metal and / or a VIII group metal as an active metal component; the second hydrodemetallization catalyst, based on the mass of the second hydrodemetallization catalyst, has an active metal content of 7wt% to 15wt% in terms of oxide, and a carrier content of 85wt% to 93wt%.

7. The grading method according to claim 1, characterized in that: The active metal weight content of any second hydrodemetallization catalyst is 0.8 to 4.5 percentage points higher than the active metal weight content of the adjacent upstream catalyst, calculated as oxide.

8. The grading method according to claim 1, 6 or 7, characterized in that: The active metals in the second hydrodemetallization catalyst include Mo and Ni; the active metals in the first hydrodemetallization catalyst adjacent to the second hydrodemetallization zone include Mo and Ni.

9. The grading method according to claim 8, characterized in that: The first hydrodemetallization catalyst has an aluminum oxide content of 88wt% to 95wt%, calculated as oxide, of Mo in an amount of 3.8wt% to 10wt%, and of Ni in an amount of 1.2wt% to 2wt%, based on the mass of the first hydrodemetallization catalyst. The second hydrodemetallization catalyst has an aluminum oxide content of 85wt% to 93wt%, calculated as oxide, of Mo in an amount of 5.5wt% to 13.5wt%, and of Ni in an amount of 1.5wt% to 3.5wt%, based on the mass of the second hydrodemetallization catalyst.

10. The grading method according to claim 8, characterized in that: Calculated as oxides, the weight content of Mo in any second hydrodemetallization catalyst is 0.5 to 3 percentage points higher than that in its adjacent upstream catalyst, and the weight content of Ni is 0.3 to 1.5 percentage points higher.

11. The grading method according to claim 10, characterized in that: The weight content of Mo in any second hydrodemetallization catalyst is 0.7 to 2.5 percentage points higher than that of its adjacent upstream catalyst, and the weight content of Ni is 0.3 to 1.0 percentage point higher, calculated as oxides.

12. The grading method according to claim 1, characterized in that: The particle size of any second hydrodemetallization catalyst is larger than the particle size of the adjacent upstream catalyst.

13. The grading method according to claim 12, characterized in that: The particle sizes of two adjacent catalysts differ by at least 0.2 mm.

14. The grading method according to claim 13, characterized in that: The particle sizes of two adjacent catalysts differ by 0.3 to 1.0 mm.

15. The grading method according to claim 1, characterized in that: The pore size of any second hydrodemetallization catalyst is larger than the pore size of the adjacent upstream catalyst.

16. The grading method according to claim 15, characterized in that: The pore sizes of two adjacent catalysts differ by at least 1.0 nm.

17. The grading method according to claim 16, characterized in that: The pore sizes of two adjacent catalysts differ by 1.2nm to 5.0nm.

18. The grading method according to claim 1, characterized in that: The porosity of any second hydrodemetallization catalyst is greater than the porosity of the adjacent upstream catalyst.

19. The grading method according to claim 18, characterized in that: The porosity of two adjacent catalysts differs by at least 0.3 percentage points.

20. The grading method according to claim 19, characterized in that: The porosity of two adjacent catalysts differs by 0.5 to 3 percentage points.

21. The grading method according to claim 2, characterized in that: The particle size of the first hydrodemetallization catalyst is 1.0-2.5 mm, the pore size is 10-30 nm, and the porosity is 42.0%-46.0%; the particle size of the second hydrodemetallization catalyst is 1.5-2.7 mm, the pore size is 15-33 nm, and the porosity is 44.0%-47.0%.

22. Use of the grading method according to any one of claims 1 to 21 in heavy oil hydrogenation reaction.

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