A catalyst for low-pressure mesoscopic hydrogenation of heavy oil and its preparation method

Abstract

The invention discloses a catalyst for low-pressure mesoscopic hydrogenation and lightening of heavy oil, which is an iron-based loaded catalyst with carbon-based microspheres as carriers, including: a carrier, an active component in-situ material and an additive; the carrier is a microsphere or a particulate carbon material, the substrate of the active component in-situ material is a metal iron salt and a molybdenum salt, and the additive includes a precipitant and deionized water; deionized water is used to dissolve and dilute the active component in-situ material and the precipitant; the mass percentage of the carrier, the active component in-situ material and the additive is: 30-70wt% of the carrier; 30-50wt% of the active component in-situ material; 5-20wt% of the precipitant; and the rest is deionized water. A corresponding preparation method is also disclosed, including: dissolving a quantitative carrier and an active component raw material in deionized water; loading on a carrier solution in the form of a suspension; depositing the active substance on the carrier solution of the suspension in the form of in-situ formation or adding a precipitant; oxidizing, filtering, washing, drying and grinding and screening the precipitate to prepare the catalyst.

Description

Technical Field

[0001] The present invention relates to the technical field of catalysts for processing and utilizing petroleum resources, and in particular to a catalyst for lightening heavy oil by low-pressure mesoscopic hydrogenation and a preparation method thereof. Background Art

[0002] Traditional heavy oil light-weight catalysts are mainly based on industrial iron-containing waste or natural iron ore. Due to their large filling volume, low activity, low energy conversion efficiency, severe mechanical wear and other factors, they are facing the situation of being gradually eliminated, such as the red mud catalyst of the German VCC process and the pyrite ore of the Japanese Nedo l coal liquefaction process. In recent years, many researchers have developed and studied heavy oil light-weight catalysts, and developed and applied two series of catalysts including supported iron-based catalysts and oil-soluble molybdenum-based catalysts. The first type is a supported catalyst with silica, activated carbon, carbon nanotubes, alumina, etc. as carriers. The second type is an oil-soluble molybdenum-based catalyst with cyclopentane acid molybdenum, heteropoly acid molybdenum, fatty acid molybdenum, etc. as active components. For example, solid supported iron-based catalysts have multiple functions. First, the carrier itself can be used as a coke inhibitor to effectively disperse coke precursors, prolong the coke induction period, prevent the fusion and growth of the "second liquid phase", and provide a surface to terminate free radical reactions, terminate the asphaltene free radical condensation reaction, and reduce reaction coke. Second, as a catalyst carrier material, it has a large specific surface area, which is conducive to the high dispersion of active components and improves hydrogenation activity. Third, by utilizing the adsorption characteristics of the carrier, the coke generated by the adsorption reaction and the raw material coke can be taken away at any time to reduce the aggregation of coke. For another example, the oil-soluble molybdenum-based series (including: cyclohexane acid molybdenum-based catalysts, fatty acid molybdenum-based catalysts, heteropolyacid molybdenum-based catalysts, etc.) catalysts have better hydrogenation performance than similar homogeneous catalysts. Under certain process parameters, the size of the MoS2 active phase formed by molybdenum conversion is ≤10nm, and it is dispersed in a single layer. Under the optimal process parameters, it can promote the efficient conversion of inferior raw materials and inhibit coking, and the synergistic effect of catalytic metals and additives can further improve the hydrogenation performance of organic molybdenum. The solid supported iron-based catalyst and oil-soluble molybdenum-based catalyst series used in the pilot test can be used for low-pressure mesoscopic hydrogenation of heavy oil, but they have their own advantages and disadvantages and are difficult to meet the needs of low-pressure mesoscopic hydrogenation of heavy oil. Through the analysis and test of the advantages and disadvantages of the existing heavy oil hydrogenation solid supported iron-based catalyst and oil-soluble molybdenum-based series and catalyst in the heavy oil low-pressure mesoscopic hydrogenation lightening test, the disadvantages are specifically reflected in:

[0003] 1. Although these catalysts show good catalytic performance in the heavy oil lightening process, since the reactors for this type of reaction are mainly suspended beds, the catalyst and the reaction materials are required to pass through the reactor at one time, which makes their preparation cost and operating cost high.

[0004] 2. Due to the different requirements for thermodynamically controlled products and kinetically controlled products, supported catalysts need to select different carriers with high and low surface areas. In addition, the preparation process of catalysts used in suspended beds is complicated, the active sites are weak, and the filling volume is large, which has great limitations in industrial applications.

[0005] 3. The lattice growth activity of oil-soluble molybdenum-based catalysts deteriorates at high temperatures, the preparation cost is high, and it is not conducive to industrial promotion.

[0006] 4. Regarding the low-pressure mesoscopic hydrogenation technology for heavy oil, the solid-supported iron-based catalyst carrier has the characteristics of coke bearing and coke suppression, but the carrier particles are large and the dispersion is poor, resulting in the solid-supported iron-based catalyst having the disadvantages of low activity, large filling volume, high overall cost, and high solid slag content in the tailings, making it difficult to achieve industrialization.

[0007] 5. Regarding the low-pressure mesoscopic hydrogenation technology for heavy oil, the oil-soluble molybdenum-based catalyst series has the characteristics of good dispersibility and high activity because its active components are in molecular state. However, the active components without a carrier are easy to aggregate and form coke. Specifically, the sulfurization time of cyclohexanecarboxylic acid molybdenum-based catalysts is long; the preparation repeatability of heteropolyacid molybdenum-based catalysts is poor; the lattice of fatty acid molybdenum-based catalysts grows and the high-temperature activity is poor under high temperature (≥400°C) reaction; and the preparation cost of the above three oil-soluble molybdenum-based catalysts is relatively high, which is not conducive to industrial promotion.

[0008] The core of the heavy oil low-pressure mesoscopic hydrogenation lightening technology is to greatly reduce the operating pressure without reducing the mass transfer efficiency and single-pass conversion rate, so that the system can save energy and reduce consumption, and the safety is greatly improved. Due to the low operating pressure and mesoscopic reaction of heavy oil low-pressure mesoscopic hydrogenation, the performance requirements of the catalyst are higher. The catalyst used in heavy oil low-pressure mesoscopic hydrogenation should have the characteristics of high activity, high selectivity, high dispersibility, high coke bearing capacity, and high cleanliness. Summary of the invention

[0009] The purpose of the present invention is to provide an iron-based catalyst with carbon-based microspheres as a carrier as a heavy oil low-pressure mesoscopic hydrogenation lightening catalyst (abbreviated as: JGCC), and to provide a preparation method for the catalyst with simple operation and mild reaction conditions.

[0010] The present invention provides a catalyst for low-pressure mesoscopic hydrogenation of heavy oil to lighten the weight, which is an iron-based supported catalyst with carbon-based microspheres as carriers, comprising: a carrier, an active component in-situ material and an additive; the carrier is a microsphere or a particulate carbon material, the base material of the active component in-situ material is a metal iron salt and a molybdenum salt, the additive comprises a precipitant and deionized water; the deionized water is used to dissolve and dilute the active component in-situ material and the precipitant;

[0011] The mass percentages of the carrier, active component in-situ material and additives are as follows: the carrier is 30-70wt%; the active component in-situ material is 30-50wt%; the precipitant is 5-20wt%; and the rest is deionized water.

[0012] Preferably, the catalyst is a supported solid iron catalyst used alone, a supported molybdenum catalyst used alone, or a supported solid iron and molybdenum catalyst.

[0013] Preferably, the carrier is carbon black, coke, calcined coke or activated carbon, and the particle size is ≥200 mesh.

[0014] Preferably, the active component in-situ material is ferrous sulfate, ferric nitrate, ferric chloride or molybdenum salt.

[0015] Preferably, the additive includes urea, ammonium carbonate or sodium hydroxide.

[0016] The second aspect of the present invention is to provide a method for preparing a catalyst for low-pressure mesoscopic hydrogenation of heavy oil to lighten the weight, which is prepared by a precipitation method and comprises:

[0017] S1, dissolving a certain amount of carrier and active component raw materials in deionized water;

[0018] S2, loaded on a carrier solution prepared in the form of a suspension;

[0019] S3, depositing the active substance on the carrier solution of the suspension in the form of in situ formation or addition of a precipitant;

[0020] S4, oxidizing, filtering, washing, drying, grinding and screening the precipitate to prepare a catalyst.

[0021] Preferably, the S1 comprises:

[0022] S11, add a certain amount of deionized water into the preparation kettle, start stirring, control the speed at 200 rpm to 500 rpm, start the circulating oil bath, and control the temperature in the kettle to be in the range of 20-70°C;

[0023] S12, weighing a certain amount of carrier and putting it into an oven to dry for later use;

[0024] S13, weigh a certain amount of active ingredient raw materials, add them into the preparation kettle, and stir them with a stirrer until they are completely dissolved.

[0025] Preferably, S2 includes:

[0026] S21, adding the dried powdered carrier into a preparation kettle and stirring for 15 to 50 minutes;

[0027] S22, weigh a certain amount of caustic soda flakes, put them into a beaker, add deionized water, and prepare alkali solution; pour the alkali solution into an alkali solution titration tank, turn on the nitrogen to replace the air in the tank, and adjust the nitrogen pressure to a first pressure range; the first pressure range is 0.05-0.1Mpa;

[0028] S23, open the titration hand valve, control a small flow rate to drip alkali solution into the preparation kettle, adjust the pH value in the preparation kettle to 5-8, and control the time to be 0.5-4h;

[0029] S24, when the pH value in the preparation kettle reaches 5-8, close the titration hand valve; at the same time, open the purge air hand valve to introduce purge air, and control the flow rate of the purge air hand valve to 10-100 L / h;

[0030] S25, after the pH value in the preparation kettle is reduced to the minimum, continue to control the small flow rate of alkali solution to drip into the preparation kettle, adjust the pH value in the kettle to 5-10, and the time is controlled to be 0.5-3h;

[0031] S26, when the pH value in the preparation kettle reaches 5-10, the titration hand valve is closed again and the timing is started, and the constant temperature is maintained for 2-5 hours; during the constant temperature process, the pH value in the preparation kettle is measured at a certain time interval, and when the pH value in the preparation kettle is lower than the set value, an alkali solution is dripped to ensure that the pH value is maintained at 5-10;

[0032] S27, when the constant temperature is finished, the purge air hand valve is closed, the drain valve of the preparation kettle is opened, and the carrier in the form of a suspension is collected into a container;

[0033] S28, draining the excess alkali solution, washing the pipe through which the alkali solution passes with water to prevent the alkali solution from clogging the pipe; washing the preparation kettle, closing the drain valve of the preparation kettle and the agitator;

[0034] Preferably, when the active substance is deposited on the carrier solution of the suspension in the form of adding a precipitant, S3 includes: adding a precipitant to the carrier solution of the suspension containing a metal salt, thereby precipitating the generated insoluble metal salt or metal hydrated oxide from the carrier solution of the suspension and obtaining a precipitate.

[0035] Preferably, S4 includes:

[0036] S41, subjecting the precipitate to oxidation, filtering, washing, drying, grinding and screening steps to obtain a bulk catalyst;

[0037] S42, packing the bulk catalyst to obtain the catalyst.

[0038] Beneficial effects of the catalyst and preparation method of the present invention:

[0039] The carbon-based microsphere carrier has small particle size, high dispersibility, and large surface area. The active components can be evenly distributed on the outer surface of the carrier. In the mesoscopic three-phase reaction, the active components on the outer surface of the catalyst can fully play their role, and the unit energy efficiency of the catalyst is significantly improved. It is fully adapted to the technical requirements of heavy oil low-pressure mesoscopic hydrogenation technology for high catalyst activity, high selectivity, high dispersibility, high coke bearing capacity, and high cleanliness; at the same time, it also meets the requirements of other general operating conditions for heavy oil hydrogenation. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the related technologies, the drawings required for use in the specific embodiments or the related technical descriptions will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0041] Figure 1 The present invention is a flow chart of a method for preparing a catalyst for lightening of heavy oil by low-pressure mesoscopic hydrogenation according to an embodiment of the present invention. DETAILED DESCRIPTION

[0042] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0043] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0044] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0045] Technical basis of the invention of the catalyst and preparation method for low-pressure mesoscopic hydrogenation of heavy oil to light oil:

[0046] 1. Mesoscopic hydrogenation technology:

[0047] (1) The process of mesoscopic hydrogenation technology: the raw heavy oil is evenly mixed with the catalyst and heat exchanged, and then mixed with the hydrogen after heat exchange into the mesoscopic pool in the reactor to form a mesoscopic state to complete the reaction. The reaction effluent product enters the separation system for gas-liquid separation; the separated hydrogen-rich gas is recovered, desulfurized, and purified through light hydrocarbons, and then pressurized by the circulating hydrogen compressor for recycling; the separated generated oil enters the product fractionation system after heat exchange and heating, and the main products of this device - liquefied gas, light naphtha, heavy naphtha, diesel, light wax, heavy wax and tail oil are obtained from the fractionation tower, among which the heavy wax is used as circulating oil for secondary hydrogenation reaction; the tail oil is directly discharged from the device as a raw material for the coking device or goes to the tank area to be used as asphalt blending material.

[0048] (2) The core of the low-pressure mesoscopic hydrogenation and light-weighting technology for heavy oil: The core of the method and system for low-pressure mesoscopic hydrogenation and light-weighting of heavy oil is to use the mesoscopic state formed by the three phases of gas, liquid and solid to carry out hydrogenation physical and chemical reactions under the mesoscopic state. To meet the requirements of the low-pressure mesoscopic hydrogenation and light-weighting technology for heavy oil, extremely high requirements are placed on the catalyst's high activity, high selectivity, high dispersibility, high coke bearing capacity, high cleanliness and other properties; at the same time, the catalyst (JGCC) must also be suitable for the requirements of heavy oil hydrogenation under other operating conditions.

[0049] 2. Technical background of carbon microsphere (carbon black, coke, calcined coke, activated carbon, etc.) supported catalyst (JGCC type):

[0050] (1) Advantages and disadvantages of existing catalysts: The advantage of existing solid supported iron-based catalysts is that the carrier has coke-bearing and coke-suppressing properties; the disadvantage is that the carrier particles are large and the dispersion is poor, which makes the catalyst activity low, the filling amount is large, the overall cost is high, and the solid slag content in the tailings is high. The advantage of oil-soluble molybdenum-based catalysts is that the active components are in molecular state, have good dispersion, and have high activity; the disadvantage is that the active components without a carrier are easy to aggregate and form coke.

[0051] (2) The type, composition, morphology, doping and surface modification of the carrier may affect the catalyst-carrier interaction and thus the catalytic activity. The catalytic activity is affected by factors such as particle size, chemical composition, metal-carrier interaction and interface effects. The finer the catalyst carrier particles, the larger the surface area, the better the dispersion of active sites and the more uniform the arrangement, and the catalytic effect in mesoscopic reactions can be significantly improved.

[0052] (3) The most fundamental way to solve these problems is to find a microsphere carrier (or an ideal molecular state) whose skeleton can support the structure of the entire catalyst, so that the active components on the surface are highly uniform and dispersed. The active components promote catalytic efficiency through changes in the morphology and valence of metals and the synergistic effect between multiple metals. This embodiment is a catalyst prepared with a carbon-based microsphere carrier. The carrier has a small particle size, high dispersibility, and a large surface area. The active components can be evenly distributed on the outer surface of the carrier, so that the active components of the catalyst can fully play a role in the mesoscopic environment, and the unit energy efficiency of the catalyst is significantly improved. And it has the advantages of the above-mentioned two major types of existing catalysts.

[0053] As a carrier, carbon-based microspheres have the properties of small particle size, good dispersibility, low density, etc., and the market resources are abundant, which is suitable for the mesoscopic reaction needs in the low-pressure mesoscopic hydrogenation technology of heavy oil. For example, the technical indicators (partial) of high wear-resistant carbon black microspheres N330, one of the carbon microspheres, are as follows:

[0054] CTAB adsorption specific surface area (103m 2 / kg): 73~85;

[0055] STSA(103m 2 / kg): 69~81;

[0056] Tinting strength (%): 96-112;

[0057] Ash content (%): ≤0.7;

[0058] 45 mesh sieve residue (%): ≤0.001;

[0059] 100 mesh sieve residue (%): ≤0.01;

[0060] Impurities: None;

[0061] 300% tensile stress: -0.5±1.5;

[0062] Subdivision content (%): ≤10.

[0063] (3) The catalyst suitable for the heavy oil low-pressure mesoscopic hydrogenation lightening technology should have the advantages of the above two categories of catalysts and eliminate their disadvantages. Through research and experiments, it was found that the key to solving the problem is to find a special microsphere carrier (or the molecular state is in an ideal state) and have the advantages of the above two categories of catalysts. After multiple pilot tests, a catalyst prepared with carbon-based microspheres as carriers fully meets the requirements of heavy oil low-pressure mesoscopic hydrogenation technology. The carbon-based microsphere carrier has a small particle size, high dispersibility, and a large surface area. The active components can be evenly distributed on the outer surface of the carrier. In the three-phase reaction in the mesoscopic state, the active components on the outer surface of the catalyst can fully play a role, and the unit energy efficiency of the catalyst is significantly improved. It is fully adapted to the technical requirements of heavy oil low-pressure mesoscopic hydrogenation technology for catalysts with high activity, high selectivity, high dispersibility, high coke bearing capacity, and high cleanliness; at the same time, it also meets the requirements of other general operating conditions for heavy oil hydrogenation.

[0064] The present invention provides a catalyst for low-pressure mesoscopic hydrogenation and lightening of heavy oil, which has high activity, high selectivity, high dispersibility, high coke bearing capacity and high cleanliness. The catalyst for low-pressure mesoscopic hydrogenation and lightening of heavy oil is an iron-based supported catalyst with carbon-based microspheres as carriers, comprising: a carrier, an active component in-situ material and an additive; the carrier is a microsphere or a particulate carbon material, the substrate of the active component in-situ material is a metal iron salt and a molybdenum salt, and the additive comprises a precipitant and deionized water; the deionized water is used to dissolve and dilute the active component in-situ material and the precipitant;

[0065] The mass percentages of the carrier, active component in-situ material and additives are as follows: the carrier is 30-70wt%; the active component in-situ material is 30-50wt%; the precipitant is 5-20wt%; and the rest is deionized water.

[0066] As a preferred embodiment, the catalyst is a supported solid iron catalyst used alone, a supported molybdenum catalyst used alone, or a supported solid iron and molybdenum catalyst.

[0067] As a preferred embodiment, the carrier is carbon black, coke, calcined coke or activated carbon, and the particle size is ≥200 mesh.

[0068] As a preferred embodiment, the active component in-situ material is ferrous sulfate, ferric nitrate, ferric chloride or molybdenum salt.

[0069] As a preferred embodiment, the additive includes urea, ammonium carbonate or sodium hydroxide.

[0070] like Figure 1As shown, this embodiment provides a method for preparing a catalyst for low-pressure mesoscopic hydrogenation of heavy oil, which is prepared by precipitation method. The precipitation method is that the active material is deposited on the carrier of the suspension in the form of in-situ formation or addition of a precipitant. That is, a precipitant is added to a solution containing a metal salt, and the generated insoluble metal salt or metal hydrated oxide is precipitated from the solution, and then the catalyst is prepared through oxidation, filtration, washing, drying, grinding and other processes. The preparation process should carefully control the speed and sequence of additives, the mixing process, the pH value and the maturation process. The selection of precipitants, temperature control, pH value regulation, stirring speed, addition sequence and speed, etc. have a huge impact on the performance of the catalyst.

[0071] The preparation method comprises:

[0072] S1, dissolving a certain amount of carrier and active component raw materials in deionized water;

[0073] As a preferred embodiment, the S1 includes:

[0074] S11, add a certain amount of deionized water into the preparation kettle, start stirring, control the speed at 200 rpm to 500 rpm, start the circulating oil bath, and control the temperature in the kettle to be in the range of 20-70°C;

[0075] S12, weighing a certain amount of carrier and putting it into an oven to dry for later use;

[0076] S13, weighing a certain amount of active ingredient raw materials and adding them into the preparation kettle, stirring them with a stirrer until they are completely dissolved;

[0077] S2, loaded on a carrier solution prepared in the form of a suspension;

[0078] As a preferred embodiment, the S2 includes:

[0079] S21, adding the dried powdered carrier into a preparation kettle and stirring for 15 to 50 minutes;

[0080] S22, weigh a certain amount of caustic soda flakes, put them into a beaker, add deionized water, and prepare alkali solution; pour the alkali solution into an alkali solution titration tank, turn on the nitrogen to replace the air in the tank, and adjust the nitrogen pressure to a first pressure range; the first pressure range is 0.05-0.1Mpa;

[0081] S23, open the titration hand valve, control a small flow rate to drip alkali solution into the preparation kettle, adjust the pH value in the preparation kettle to 5-8, and control the time to be 0.5-4h;

[0082] S24, when the pH value in the preparation kettle reaches 5-8, close the titration hand valve; at the same time, open the purge air hand valve to introduce purge air, and control the flow rate of the purge air hand valve to 10-100 L / h;

[0083] S25, after the pH value in the preparation kettle is reduced to the minimum, continue to control the small flow rate of alkali solution to drip into the preparation kettle, adjust the pH value in the kettle to 5-10, and the time is controlled to be 0.5-3h;

[0084] S26, when the pH value in the preparation kettle reaches 5-10, the titration hand valve is closed again and the timing is started, and the constant temperature is maintained for 2-5 hours; during the constant temperature process, the pH value in the preparation kettle is measured at a certain time interval, and when the pH value in the preparation kettle is lower than the set value, an alkali solution is dripped to ensure that the pH value is maintained at 5-10;

[0085] S27, when the constant temperature is finished, the purge air hand valve is closed, the drain valve of the preparation kettle is opened, and the carrier in the form of a suspension is collected into a container;

[0086] S28, draining the excess alkali solution, washing the pipe through which the alkali solution passes with water to prevent the alkali solution from clogging the pipe; washing the preparation kettle, closing the drain valve of the preparation kettle and the agitator;

[0087] S3, depositing the active substance on the carrier solution of the suspension in the form of in-situ formation or addition of a precipitant.

[0088] As a preferred embodiment, when the active substance is deposited on the carrier solution of the suspension in the form of adding a precipitant, S3 includes: adding a precipitant to the carrier solution of the suspension containing a metal salt, thereby precipitating the generated sparingly soluble metal salt or metal hydrated oxide from the carrier solution of the suspension and obtaining a precipitate;

[0089] S4, oxidizing, filtering, washing, drying, grinding and screening the precipitate to prepare a catalyst.

[0090] As a preferred implementation, the S4 includes:

[0091] S41, subjecting the precipitate to oxidation, filtering, washing, drying, grinding and screening steps to obtain a bulk catalyst;

[0092] S42, packing the bulk catalyst to obtain the catalyst.

[0093] Preparation method application example:

[0094] Taking the 15L catalyst preparation reactor as an example, the specific process steps are as follows:

[0095] (1) Measure 10L of deionized water and add it to the preparation kettle, start stirring, control the speed to 200rpm-500rpm, start the circulating oil bath, and control the temperature in the kettle to 20-70°C;

[0096] (2) Weigh 600-1800g of carbon black powder and put it into an oven for drying;

[0097] (3) Weigh 500-1000 g of any active ingredient raw material of iron salt or molybdenum salt, add it to the preparation kettle, and stir until it is completely dissolved;

[0098] (4) Add the dried powdered carbon black powder into the preparation kettle and stir for 15 to 50 minutes;

[0099] (5) Weigh 100-400g of caustic soda flakes into a beaker and add deionized water to prepare 5L of alkali solution. Pour the alkali solution into the alkali solution titration tank, slightly open the nitrogen to replace the air in the tank, adjust the nitrogen pressure to 0.05-0.1Mpa, slightly open the titration hand valve, control the small flow rate to drip the alkali solution, adjust the pH value in the kettle to 5-8, and control the time to be 0.5-4h;

[0100] (6) When the pH value in the preparation kettle reaches 5-8, turn off the alkali solution, open the purge air hand valve to let in the purge air, and control the flow rate to 10-100 L / h;

[0101] (7) After the pH value in the preparation kettle drops to the minimum, continue to control the small flow rate of alkali solution to adjust the pH value in the kettle to 5-10, and the time is controlled at 0.5-3h;

[0102] (8) When the pH value in the preparation kettle is 5-10, turn off the alkali solution titration, start timing, and keep the temperature constant for 2-5 hours. During this period, if the pH is lower than 5-10, add alkali solution to ensure that the pH value is 5-10;

[0103] (9) After the constant temperature is reached, close the purge air hand valve, open the preparation kettle drain valve and collect the carrier in the form of suspension into a container;

[0104] (10) draining the excess alkali solution and washing the pipe through which the alkali solution passes with water to prevent the alkali solution from clogging the pipe; cleaning the preparation kettle and closing the drain valve of the preparation kettle and the agitator;

[0105] (11) adding a precipitant to a carrier solution containing a suspension of a metal salt, thereby precipitating the generated sparingly soluble metal salt or metal hydrated oxide from the carrier solution of the suspension and obtaining a precipitate;

[0106] (12) The precipitate is oxidized, filtered, washed, dried, and ground and sieved to prepare a catalyst.

[0107] Evaluation results of the pilot plant of the prepared catalyst

[0108] The heavy oil low pressure mesoscopic hydrogenation catalyst (JGCC), activated carbon iron-based catalyst, fatty acid molybdenum-based catalyst and heteropolyacid molybdenum-based catalyst were respectively applied to the heavy oil low pressure mesoscopic hydrogenation lightening technology, and the catalyst evaluation was continuously carried out on a 3.3kg / h (30t / a) heavy oil low pressure mesoscopic hydrogenation pilot unit using high sulfur vacuum heavy oil (sulfur content 3.4wt%) as raw material. The operating reaction conditions are: reaction temperature 430-435℃; reaction pressure 3MPa (hydrogen purity>99%); catalyst addition amount is calculated based on the total raw material, and the actual addition amount, reaction temperature, and reaction conversion rate are shown in Table 1 Catalyst Evaluation Results.

[0109] Table 1 Catalyst evaluation results

[0110] catalyst Filling amount Reaction temperature / ℃ Conversion Rate % Mesoscopic Catalyst (JGCC) 0.75％ 430 73.65 Activated carbon iron-based catalyst 1.50％ 430 73.8 Fatty acid molybdenum-based catalyst 150ppm 430 73.6 Heteropolyacid molybdenum-based catalyst 150ppm 430 76.8

[0111] The evaluation test results in Table 1 show that: under the same operating conditions, the filling amount of the heavy oil low-pressure mesoscopic hydrogenation catalyst (JGCC) is halved, and the conversion rate is similar to that of the similar heavy oil hydrogenation light-weight catalyst. Therefore, the heavy oil low-pressure mesoscopic hydrogenation catalyst (JGCC) of this embodiment still meets the requirements of heavy oil low-pressure mesoscopic hydrogenation light-weight at a low filling amount. The catalyst has the characteristics of high activity, high selectivity, high dispersibility, high coke bearing capacity, high cleanliness, etc. It is superior to other catalysts in the mesoscopic hydrogenation technology test, has high cost performance, and has a broader industrial application prospect.

[0112] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. Application of a catalyst in low-pressure mesoscopic hydrogenation of heavy oil to light oil, characterized in that: The reaction pressure of the heavy oil low-pressure mesoscopic hydrogenation lightening reaction is 3MPa, the catalyst is an iron-based supported catalyst with carbon-based microspheres as carriers, and the catalyst raw materials include: carriers, active component in-situ materials and additives; the carrier is carbon black, coke, calcined coke or activated carbon, and the particle size is ≥200 mesh; the active component in-situ materials are metal iron salts and molybdenum salts, the metal iron salts are ferrous sulfate, ferric nitrate or ferric chloride, and the additives include precipitants and deionized water; the deionized water is used to dissolve and dilute the active component in-situ materials and the precipitant; The weight percentages of the carrier, active component in-situ material and additives are as follows: the carrier is 30-70wt%; the active component in-situ material is 30-50wt%; the precipitant is 5-20wt%; the rest is deionized water; the catalyst is a supported solid iron-molybdenum catalyst; The preparation method of the catalyst comprises: S1, add a certain amount of deionized water into the preparation kettle, start stirring, control the speed at 200rpm-500rpm, start the circulating oil bath, and control the temperature in the kettle to be in the range of 20-70℃; S2, weigh a certain amount of carrier and put it into an oven to dry for later use; S3, weighing a certain amount of active ingredient raw materials and adding them into the preparation kettle, stirring them with a stirrer until they are completely dissolved; S4, adding the dried powdered carrier into the preparation kettle and stirring for 15 to 50 minutes; S5, weighing a certain amount of caustic soda flakes, putting them into a beaker, adding deionized water, and preparing alkali solution; pouring the alkali solution into an alkali solution titration tank, turning on the nitrogen to replace the air in the tank, and adjusting the nitrogen pressure to a first pressure range; the first pressure range is 0.05-0.1Mpa; S6, open the titration hand valve, control a small flow rate to drip alkali solution into the preparation kettle, adjust the pH value in the preparation kettle to 5-8, and control the time to be 0.5-4h; S7, when the pH value in the preparation kettle reaches 5-8, close the titration hand valve; at the same time, open the purge air hand valve to introduce purge air, and control the flow rate of the purge air hand valve to 10-100 L / h; S8, after the pH value in the preparation kettle drops to the minimum, continue to control the small flow rate of alkali solution to drip into the preparation kettle, adjust the pH value in the kettle to 5-10, and the time is controlled to be 0.5-3h; S9, when the pH value in the preparation kettle reaches 5-10, close the titration hand valve again and start timing, and keep the temperature constant for 2-5 hours; during the constant temperature process, measure the pH value in the preparation kettle at a certain time interval, and when the pH value in the preparation kettle is lower than the set value, add alkali solution to ensure that the pH value remains at 5-10; S10, when the constant temperature is finished, the purge air hand valve is closed, the drain valve of the preparation kettle is opened, and the carrier in the form of a suspension is collected into a container; S11, draining the excess alkali solution, washing the pipe through which the alkali solution passes with water to prevent the alkali solution from clogging the pipe; washing the preparation kettle, closing the drain valve of the preparation kettle and the agitator; S12, adding a precipitant to the carrier solution containing the metal salt suspension, thereby precipitating the generated sparingly soluble metal salt or metal hydrated oxide from the carrier solution of the suspension and obtaining a precipitate; S13, subjecting the precipitate to oxidation, filtering, washing, drying, grinding and screening steps to obtain a bulk catalyst; S14, packing the bulk catalyst to obtain the catalyst.

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