A method for hydrogenation

Abstract

The present invention discloses a hydrogenation method, wherein the raw oil passes through a first hydroprocessing reaction zone, an isomerization-shallow cracking reaction zone, and a second hydroprocessing reaction zone in sequence, wherein the isomerization-shallow cracking reaction zone is loaded with a catalyst containing a cracking component. The method is applicable to the hydroprocessing process of various distillate oils, and is particularly applicable to the processing of slurry bed and ebullating bed wax oil.

Description

Technical Field

[0001] The invention relates to a hydrogenation method, in particular to a deep denitrogenation hydrogenation method for raw oil with high aromatic content. Background Art

[0002] In the future, oil will remain the world's main primary energy source, and the world's oil demand will continue to grow steadily, with the Asia-Pacific region being the most active. After years of development, global refining technology has formed a complete refining technology system, and can now provide various crude oil processing technology solutions for different refineries in the world. In recent years, around the themes of energy conservation and environmental protection, low carbon emissions, improving economic benefits and achieving sustainable development, the world has made great progress in key technical fields such as coal-to-oil technology, deep processing of heavy oil (residue oil), clean fuel production, oil-chemical combination, alternative fuels and lubricant base oil production.

[0003] In modern oil refining technology, hydrocracking has become one of the important process technologies for deep processing of heavy oil. The core of hydrocracking technology is the catalyst, including pretreatment catalyst and cracking catalyst. The main function of the hydrocracking pretreatment catalyst is to remove impurities such as sulfur, nitrogen, oxygen and heavy metals contained in the raw materials by hydrogenation and to hydrogenate saturated polycyclic aromatic hydrocarbons to improve the properties of oil products. Because the nitrides in the raw oil, especially the alkaline nitrides, can poison the acid center of the cracking catalyst, the hydrodenitrogenation performance is an important indicator for measuring the hydrocracking pretreatment catalyst.

[0004] CN 109718867 A relates to the field of hydrorefining catalysts, and discloses a hydrorefining catalyst system and its application, a preparation method of the hydrorefining catalyst, and a method for hydrorefining distillate oil. The catalyst system includes a first and a second catalyst bed; the first catalyst contains alumina, a hydrodesulfurization catalytic active component and a carboxylic acid; the second catalyst contains an inorganic refractory component, a hydrodesulfurization catalytic active component and a carboxylic acid; the second inorganic refractory component contains amorphous silicon aluminum and / or molecular sieve and alumina; the first and second catalysts both have a pore size of 4-40nm and a pore size of 100-300nm, and the pore volume of the pore size of 4-40nm accounts for 60-95% of the total pore volume, and the pore volume of the pore size of 100-300nm accounts for 0.5-30% of the total pore volume. The first and second catalysts have a pore size of 100-300nm, good performance, shortened preparation process, and the ability of the catalyst system to process distillate oil is improved.

[0005] CN103805251A discloses a method for producing hydrogenated low-freezing point diesel using grading technology. After the diesel raw material is mixed with hydrogen, it passes through at least two serially connected hydrogenation reaction zones in sequence. According to the material flow direction, the hydrogenation reaction zones sequentially include a composite bed of refined and modified catalysts mixed with a hydrogenation refining catalyst and a hydrogenation reforming catalyst and a bed of hydrodecondensation catalysts; the reaction effluent obtained from the last hydrogenation reaction zone is separated and fractionated to obtain a low-freezing point diesel product. The method of the present invention reasonably combines and utilizes the temperature drop in the hydrodecondensation process and the temperature rise in the hydrodecondensation process, thereby increasing the yield of diesel while producing low-freezing and low-sulfur diesel, reducing the hot spot temperature of the device, and extending the operating cycle; in addition, the consumption of cold hydrogen or the gas loss of the heating furnace is reduced, saving operating costs.

[0006] CN 111073689 A discloses a heavy oil hydrogenation treatment method, comprising the following contents: the heavy oil raw material enters the hydrogenation reactor, contacts with the hydrogenation catalyst bed layer for hydrogenation reaction, and the reaction product flows out of the reactor; wherein the hydrogenation catalyst bed layer is graded and loaded with at least two levels of sulfurized hydrogenation catalyst along the logistics direction, and the average length of the metal active phase crystal increases step by step, the average number of crystal layers decreases step by step, the content of active components increases step by step, and the aperture decreases step by step along the logistics direction. The method of the present invention adopts a specific catalyst gradation to effectively utilize the catalyst active center, improve the coupling reaction performance of the active center structure and the reactant molecular structure, greatly improve the stability of the hydrogenation reaction of the entire system, such as demetallization, desulfurization, denitrogenation, etc., and is conducive to the deep hydrogenation of heavy oil.

[0007] These methods do not involve how to improve the deep denitrification performance of the entire reactor. Especially for slurry bed and boiling bed wax oil, the aromatic content is high, there are more side chain structures, and the nitrogen-containing molecules have large steric hindrance, making the denitrification reaction more difficult. Summary of the invention

[0008] In view of the problems existing in the prior art, the present invention provides a hydroprocessing method, which is applicable to the hydroprocessing process of various distillate oils, especially to the processing of slurry bed and ebullating bed wax oil. The method can not only improve the deep denitrification performance of the hydroprocessing reactor, but also improve the aromatic saturation performance of the catalyst system.

[0009] A hydrogenation method, wherein the crude oil passes through a first hydroprocessing reaction zone, an isomerization-shallow cracking reaction zone, and a second hydroprocessing reaction zone in sequence, wherein the isomerization-shallow cracking reaction zone is loaded with a catalyst containing cracking components.

[0010] In the method of the present invention, the peak temperature (°C) of hydrogen consumption of the hydroprocessing catalyst H2-TPR loaded in the first hydroprocessing reaction zone is higher than the peak temperature of hydrogen consumption of the hydroprocessing catalyst H2-TPR loaded in the second hydroprocessing reaction zone, generally 10°C-200°C higher, preferably 10°C-100°C higher, and further preferably 10°C-60°C higher.

[0011] In the method of the present invention, the infrared total acidity of the catalyst loaded in the isomerization-shallow cracking reaction zone is higher than that of the hydroprocessing catalyst loaded in the first hydroprocessing reaction zone and the hydroprocessing catalyst loaded in the second hydroprocessing reaction zone, generally 0.05mmol / g-0.20mmol / g higher, preferably 0.10mmol / g-0.15mmol / g higher.

[0012] In the method of the present invention, the peak temperature of hydrogen consumption of the hydroprocessing catalyst is determined by the H2-TPR method. The peak temperature range is between 230°C and 480°C, preferably between 280°C and 450°C.

[0013] In the above method, the volume ratio of the catalyst loaded in different reaction zones is as follows: first hydroprocessing reaction zone: isomerization-shallow cracking reaction zone: second hydroprocessing reaction zone is 1.0~10.0: 0.2~2.0: 0.5~8.0.

[0014] In the above method, any reaction zone can be loaded with one catalyst or multiple catalysts in a graded manner, preferably one catalyst. When multiple catalysts are loaded, the loading volume ratio of adjacent catalyst beds is 1:20 to 20:1, preferably 1:10 to 10:1, and more preferably 1:5 to 5:1.

[0015] In the above method, the raw materials are various distillate oils, including various diesel, VGO, CGO, DAO and mixed oils of two or more thereof, and their main properties are as follows: distillation range, initial distillation point greater than 180°C, final distillation point less than 600°C; density, 0.8000~0.9500 / g·cm -3 (20℃); Nitrogen content, 100~8000μg·g -1 ; Sulfur content, 0.05wt%~5.0wt%, aromatics content 20wt%~80wt%.

[0016] In the above method, the raw material passes through the first hydroprocessing reaction zone to reduce the nitrogen content in the raw oil to less than 300 ppm, and then passes through the shallow cracking action of the high acid catalyst to expose the nitrogen-containing heteroatoms, and then enters the deep denitrification reaction zone, and undergoes the denitrification reaction of the hydroprocessing catalyst to achieve the purpose of deep denitrification.

[0017] In the above method, the reaction temperature of different reaction zones is gradually increased, depending on the reaction raw materials and reaction conditions. The reaction temperature of the first hydroprocessing reaction zone is 280°C to 380°C, the reaction temperature of the isomerization-shallow cracking reaction zone is 350°C to 400°C, and the reaction temperature of the second hydroprocessing reaction zone is 370°C to 420°C. In the same reaction system, the average reaction temperature of different reaction zones increases by 10°C to 30°C.

[0018] In the above method, the first hydroprocessing reaction zone is filled with a hydroprocessing catalyst; the isomerization-shallow cracking reaction zone is filled with a high-acidity hydroprocessing catalyst containing a strong acid component; and the second hydroprocessing reaction zone is filled with a hydroprocessing catalyst.

[0019] In the above method, the hydroprocessing catalyst contains group VIB and group VIII metal components. The active metal of group VIB is W and / or Mo, and the active metal of group VIII is Ni and / or Co. The active metals in the final hydroprocessing catalyst are generally 9% to 50% of group VIB metal oxides and 1% to 15% of group VIII metal oxides by weight of oxides. The catalyst carrier is a porous refractory oxide, such as alumina, silicon dioxide, magnesium oxide, zirconium oxide, boron oxide, titanium dioxide, etc. According to the use requirements of the catalyst, suitable additives can be added, such as one or more of fluorine, phosphorus, boron, silicon, magnesium, zirconium, etc.

[0020] The highly acidic hydrogenation catalyst of the present invention contains molecular sieves and / or silicon-aluminum components. The molecular sieves are preferably ZSM-5 and / or Y-type molecular sieves and / or beta molecular sieves. Based on the weight of the hydrogenation reforming catalyst carrier, the content of the molecular sieve is 1% to 15%, the content of the silicon-aluminum component is 0 to 85%, and the content of aluminum oxide is 3% to 99%, preferably the content of the molecular sieve is 1% to 10%, the content of the silicon-aluminum component is 0 to 65%, and the content of aluminum oxide is 10% to 90%.

[0021] The silicon-aluminum component of the present invention refers to amorphous silicon-aluminum powder, wherein the silicon content in the form of oxide is 10% to 80%.

[0022] The highly acidic hydrogenation catalyst of the present invention has a catalyst carrier content of 55.0wt% to 93.5wt%, preferably 60.0wt% to 90.0wt%, a Group VIB metal oxide content of 5.0wt% to 35.0wt%, preferably 10.0wt% to 30.0wt%, and a Group VIII metal oxide content of 0.5wt% to 15.0wt%, preferably 2.0wt% to 10.0wt%, based on the weight of the catalyst.

[0023] By adopting the method of the present invention, the reaction temperature gradually rises along the direction of the reactant flow, while the peak temperature of hydrogen consumption of the hydroprocessing catalyst H2-TPR gradually weakens, the reaction effect is good at high temperature, and the effect of the hydrogenation catalyst in different reaction areas is beneficial to exerting the denitrification performance of the catalyst. Under the action of the highly acidic catalyst in the isomerization-shallow cracking reaction zone, the difficulty of removing a small amount of difficult-to-denitrify compounds in the raw material is reduced. The graded loading method of this catalyst is beneficial to improving the overall denitrification effect of the device, and is particularly suitable for the treatment process of high aromatic raw materials such as boiling bed wax oil and slurry bed wax oil. DETAILED DESCRIPTION

[0024] H2-TPR characterization was performed using a fully automatic chemisorption instrument (AMI-200) from Altamira, USA. The carrier gas was high-purity argon, and the sample was pretreated at 485°C for 1 h before the measurement. Then 5% H2-Ar was used as the reaction gas and the temperature was programmed to 700°C at a heating rate of 10°C / min.

[0025] The total infrared acid content of the sample surface was determined by a Nicolet-560 infrared spectrophotometer. The pure sample was pressed into tablets, each weighing 20 mg. After the sample was purified at 500°C, pyridine was used as a probe molecule for adsorption and determination.

[0026] In the present invention, the hydroprocessing catalyst with different peak temperatures of H2-TPR hydrogen consumption can be commercially available or prepared by any existing catalyst adjustment technology. Take the introduction of different inorganic or organic additives in the process of carrier and catalyst preparation as an example, such as introducing different inorganic or organic additives in the process of carrier and catalyst preparation, changing the heat treatment temperature of the catalyst, etc. The inorganic additive is one or more of fluorine, silicon, phosphorus, boron, magnesium, zirconium, etc. The organic additive is one or more of nitrogen-containing organic compounds, sulfur-containing organic compounds and oxygen-containing organic compounds. The inorganic or organic additive can be introduced in any step, such as before, at the same time and after the impregnation of Group VIB and Group VIII metal components. The organic additive is one or more of nitrogen-containing organic compounds, sulfur-containing organic compounds and oxygen-containing organic compounds. The organic additive can be introduced in any step, such as before, at the same time and after the impregnation of Group VIB and Group VIII metal components. The types of organic additives are well known to those skilled in the art. The nitrogen-containing organic compound is an organic compound containing at least one covalently bonded nitrogen atom, such as ethanolamine, diethanolamine, triethanolamine, ethylenediaminetetraacetic acid (EDTA), nitrilotriacetic acid (NTA) and ethylenediaminetetraacetic acid. The sulfur-containing organic compound is an organic compound containing at least one covalently bonded sulfur atom, such as mercaptan (general formula R-SH), sulfide (general formula R-S-R), disulfide (general formula R-S-S-R), and R in these sulfur-containing compounds is an alkyl group containing 1 to 10 carbon atoms, such as ethyl mercaptan, ethylpropyl sulfide, dimethyl disulfide, etc. The sulfur-containing organic compound may contain one or more carboxyl, carbonyl, ester, ether, hydroxyl, and thiol group substitutions, such as thioglycolic acid, thiopropionic acid, dithiopropanol, etc. In addition to the above-mentioned sulfur-containing compounds, sulfone and sulfoxide compounds may be included, such as dimethyl sulfoxide, dimethyl sulfone, etc. The oxygen-containing organic compound is an organic compound containing at least one carbon atom and one oxygen atom. The oxygen-containing part can be a carboxyl, carbonyl, hydroxyl part or a combination thereof. These substances can be acids, such as acetic acid, oxalic acid, malonic acid, tartaric acid, malic acid, citric acid, etc., alcohols, such as ethylene glycol, propylene glycol, butylene glycol, glycerol, trimethylolethane, etc., ethers, such as diethylene glycol, dipropylene glycol, triethylene glycol, tributylene glycol, tetraethylene glycol, polyethylene glycol, etc., sugars, such as glucose, fructose, lactose, maltose, sucrose, etc., and can also be ketones, phenols, aldehydes and lipids. Different drying and / or calcination heat treatment temperatures also have an important influence on the strength of the interaction between the active metal of the hydroprocessing catalyst and the carrier. When treated at low temperature, the interaction between the active metal and the carrier is weak; when treated at high temperature, the interaction between the active metal of the hydroprocessing catalyst and the carrier is strong.The low temperature and high temperature are relative, and the treatment temperature range is 70°C~700°C. For example, you can customize the heat treatment temperature of 70°C~300°C, preferably 100°C~200°C as low temperature treatment; the heat treatment temperature of 320°C~700°C, preferably 380°C~600°C is considered as high temperature treatment.

[0027] The detailed process of the present invention is further described below by way of examples, but the present invention should not be considered to be limited to these examples. In the following examples and comparative examples, % are all mass percentages unless otherwise specified.

[0028] The properties of the carriers used in the examples and comparative examples are shown in Table 1. The SiO2 content in the silicon-aluminum component is 45%.

[0029] Table 1 Properties of the carriers used in the examples and comparative examples

[0030]

[0031] Example 1

[0032] This example provides the preparation method of the catalyst used in the examples and comparative examples, but the following preparation method is not the only one and does not constitute a limitation to the present invention.

[0033] Preparation method of catalyst A: The carrier Z1 is impregnated with equal volumes of impregnation solution containing Mo and Ni, dried at 120°C for 3h, and calcined at 480°C for 2h. The obtained catalyst is recorded as A.

[0034] Preparation method of catalyst B: The carrier Z2 is impregnated with equal volumes of impregnation solution containing Mo and Ni, dried at 120°C for 3h, and calcined at 480°C for 2h. The obtained catalyst is recorded as B.

[0035] Preparation method of catalyst C: Carrier Z3 is impregnated with equal volumes of impregnation solution containing Mo and Ni, the impregnation solution contains citric acid, and the molar ratio of citric acid to nickel atoms is 0.5:1. The catalyst is dried at 120°C for 3h and is recorded as C.

[0036] Preparation method of catalyst D: The carrier Z3 is impregnated with equal volumes of impregnation solutions containing Mo and Ni, dried at 120°C for 3h, and calcined at 430°C for 2h. The obtained catalyst is recorded as D.

[0037] Table 2 Main properties of the prepared oxidized catalysts

[0038]

[0039] Example 2

[0040] This example provides a loading scheme for evaluating the catalyst. Three reaction beds are set along the direction of the reactant flow, with bed volumes of 75 mL, 10 mL and 15 mL, respectively, and the reaction temperatures are controlled at 350°C, 370°C and 380°C, respectively.

[0041] The test number is S1: the three reaction beds are sequentially loaded with catalyst A, catalyst B and catalyst C along the direction of reactant flow.

[0042] The test number is S2: along the direction of the reactant flow, the three reaction beds are sequentially filled with catalysts A and D (volume of A: 35 mL, volume of D: 40 mL), catalyst B and catalyst C.

[0043] The test number is S3: the three reaction beds are sequentially loaded with catalyst D, catalyst B and catalyst C along the direction of the reactant flow.

[0044] Comparative Example 1

[0045] This comparative example provides a loading scheme for evaluating the catalyst. Three reaction beds are set along the direction of the reactant flow, with bed volumes of 70 mL, 10 mL and 20 mL respectively, and the reaction temperatures are controlled at 350°C, 370°C and 380°C respectively.

[0046] The test number is D1: the three reaction beds are sequentially loaded with catalyst C, catalyst B and catalyst A along the direction of reactant flow.

[0047] The test number is D2: along the direction of the reactant flow, the three reaction beds are sequentially loaded with catalyst A, catalyst A and catalyst A.

[0048] The test number is D3: the three reaction beds are sequentially loaded with catalyst C, catalyst C and catalyst C along the direction of reactant flow.

[0049] Example 3

[0050] This example is an activity evaluation experiment of the catalyst.

[0051] The catalyst activity evaluation experiment was carried out on a three-tube series small hydrogenation unit. The catalyst was presulfurized before the activity evaluation. The catalyst evaluation conditions were a total reaction pressure of 15.0 MPa and a liquid hourly space velocity of 1.0 h -1 , hydrogen-to-oil volume ratio is 1100:1, the properties of the raw oil used in the activity evaluation experiment are shown in Table 3, and the activity evaluation results are shown in Table 4.

[0052] Table 3 Raw oil properties

[0053]

[0054] Table 4500 hours catalyst activity evaluation results

[0055]

[0056] It can be seen from the evaluation results in Table 4 that, compared with the comparative example, the denitrification activity of the catalyst system is greatly improved by the loading method of the hydroprocessing catalyst of the present invention, and the aromatic saturation performance is also good, which can provide high-quality feed for the hydrocracking stage.

Claims

1. A hydrogenation method, characterized in that: The feedstock oil passes through the first hydroprocessing reaction zone, the isomerization-shallow cracking reaction zone, and the second hydroprocessing reaction zone in sequence, wherein the isomerization-shallow cracking reaction zone is loaded with a catalyst containing a cracking component; The reaction temperature of the first hydroprocessing reaction zone is 280°C-380°C, the reaction temperature of the isomerization-shallow cracking reaction zone is 350°C-400°C, and the reaction temperature of the second hydroprocessing reaction zone is 370°C-420°C. The average reaction temperature of different reaction zones increases by 10°C-30°C successively. The peak temperature of hydrogen consumption of the hydroprocessing catalyst H2-TPR loaded in the first hydroprocessing reaction zone is 10°C-200°C higher than the peak temperature of hydrogen consumption of the hydroprocessing catalyst H2-TPR loaded in the second hydroprocessing reaction zone; The infrared total acidity of the catalyst loaded in the isomerization-shallow cracking reaction zone is 0.05 mmol / g-0.20 mmol / g higher than that of the hydroprocessing catalyst loaded in the first hydroprocessing reaction zone and the hydroprocessing catalyst loaded in the second hydroprocessing reaction zone; The peak temperature range of hydrogen consumption of the hydroprocessing catalyst loaded in the first hydroprocessing reaction zone and the second hydroprocessing reaction zone determined by the H2-TPR method is between 230°C and 480°C.

2. The method according to claim 1, characterized in that: The peak temperature of hydrogen consumption of the hydroprocessing catalyst H2-TPR loaded in the first hydroprocessing reaction zone is 10°C-100°C higher than the peak temperature of hydrogen consumption of the hydroprocessing catalyst H2-TPR loaded in the second hydroprocessing reaction zone.

3. The method according to claim 2, characterized in that: The peak temperature of hydrogen consumption of the hydroprocessing catalyst H2-TPR loaded in the first hydroprocessing reaction zone is 10°C-60°C higher than the peak temperature of hydrogen consumption of the hydroprocessing catalyst H2-TPR loaded in the second hydroprocessing reaction zone.

4. The method according to claim 1, characterized in that: The total infrared acidity of the catalyst loaded in the isomerization-shallow cracking reaction zone is 0.10 mmol / g-0.15 mmol / g higher than that of the hydroprocessing catalyst loaded in the first hydroprocessing reaction zone and the hydroprocessing catalyst loaded in the second hydroprocessing reaction zone.

5. The method according to claim 1, characterized in that: The peak temperature range of hydrogen consumption of the hydroprocessing catalyst loaded in the first hydroprocessing reaction zone and the second hydroprocessing reaction zone determined by the H2-TPR method is 280°C-450°C.

6. The method according to claim 1, characterized in that: The raw oil includes various diesel, VGO, CGO, DAO and mixed oils of two or more thereof, and its main properties are as follows: distillation range, initial distillation point greater than 180°C, final distillation point less than 600°C; density at 20°C is 0.8000-0.9500g / cm 3 ; Nitrogen content 100-8000μg / g; sulfur content 0.05wt%-5.0wt%, aromatics content 20wt%-80wt%.

7. The method according to claim 1, characterized in that: The feedstock oil is passed through the first hydroprocessing reaction zone to reduce the nitrogen content in the feedstock oil to less than 300 ppm.

8. The method according to claim 1, characterized in that: The hydroprocessing catalysts loaded in the first hydroprocessing reaction zone and the second hydroprocessing reaction zone contain 9% to 50% of Group VIB metal oxides and 1% to 15% of Group VIII metal oxides in terms of active metal weight of oxides.

9. The method according to claim 1, characterized in that: The catalyst containing the cracking component has a molecular sieve content of 1%-15%, a silicon-aluminum content of 0-85%, and an alumina content of 3%-99% based on the weight of the catalyst.

10. The method according to claim 9, characterized in that: The catalyst containing the cracking component has a molecular sieve content of 1%-10%, a silicon-aluminum content of 0-65%, and an alumina content of 10%-90%, based on the weight of the catalyst.

11. The method according to claim 9, characterized in that: The catalyst containing the cracking component has a Group VIB metal oxide content of 5.0 wt% to 35.0 wt% and a Group VIII metal oxide content of 0.5 wt% to 15.0 wt% based on the weight of the catalyst.

12. The method according to claim 11, characterized in that: The catalyst containing the cracking component has a Group VIB metal oxide content of 10.0 wt% to 30.0 wt% and a Group VIII metal oxide content of 2.0 wt% to 10.0 wt% based on the weight of the catalyst.

Images