CN110964567A

CN110964567A - Method for producing jet fuel

Info

Publication number: CN110964567A
Application number: CN201811145242.4A
Authority: CN
Inventors: 张锐; 习远兵; 李善清; 丁石; 刘锋; 夏国富
Original assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Current assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Priority date: 2018-09-29
Filing date: 2018-09-29
Publication date: 2020-04-07

Abstract

The invention relates to a method for producing jet fuel, which comprises the steps of mixing kerosene fraction raw oil with hydrogen-containing material flow, sequentially passing through a first hydrogenation reaction zone and a second hydrogenation reaction zone to contact with a hydrofining catalyst for reaction, and carrying out gas-liquid separation and liquid-phase material fractionation on the hydrogenated material to obtain a jet fuel component. The method provided by the invention can be used for processing the high-nitrogen kerosene raw oil, and producing the jet fuel component with the basic nitrogen content of less than 3 mu g/g and the Saybolt color of more than 25 under relatively mild conditions, so that the whole catalyst system has better stability, and the running period of the device is obviously prolonged.

Description

Method for producing jet fuel

Technical Field

The invention relates to the field of hydrofining of distillate oil, in particular to a hydrogenation method for producing jet fuel.

Background

Currently, the aviation transportation industry in China keeps developing rapidly, the annual consumption of jet fuel (also called aviation kerosene, referred to as aviation kerosene for short) exceeds three million tons, and the development of the jet fuel technology is emphasized from the consideration of the safety of national energy strategy. At present, jet fuel mainly comes from a normal first-line fraction of an atmospheric distillation device, and the main quality problems of a straight-run jet fuel fraction are that mercaptan exceeds the standard, and the acid value and the color need to be improved. The existing hydrorefining process is widely applied to a trickle bed jet fuel hydrorefining technology, and the technology is used for carrying out hydrotreating under the mild process condition, mainly reduces high mercaptan in straight-run jet fuel fraction to be less than 20 mu g/g, and simultaneously improves the acid value and the color of an oil product. In addition, the nitrogen content in the product is not limited in the jet fuel standard GB6537-20063, so that the widely-applied shallow hydrofining in the prior art is only suitable for removing mercaptan in the raw material and cannot obviously remove nitrogen-containing compounds in the high-nitrogen raw oil.

With the continuous increase of high-sulfur and high-nitrogen crude oil processed by enterprises, the change of raw oil varieties and the energy expansion and transformation of devices, jet fuel products have a series of problems of poor color stability, long-term stable storage and the like. Numerous studies have shown that the components responsible for the color change in jet fuels are primarily trace non-hydrocarbon components, including oxygenates, nitrogen-containing compounds, and sulfur-containing compounds. Wherein, the alkaline nitride is easy to generate oxidation reaction with oxygen dissolved in oil products to generate free radicals at a lower temperature, and initiate unstable hydrocarbon to generate chain reaction to generate colored colloid dissolved in oil, so that the color of jet fuel products is darkened. The results of the studies show that when the basic nitrogen content is higher than 3. mu.g/g, the jet fuel has poor color stability and cannot be stored stably for a long period of time.

The hydrogenation technology plays an important role in the production of clean fuels as an effective desulfurization and denitrification means. For the hydrofining mercaptan removal of straight-run jet fuel fractions, the mercaptan removal is facilitated at low reaction pressure; the method is favorable for removing nitride under high reaction pressure, effectively inhibits the formation of carbon deposition precursors on the surface of the catalyst, and is favorable for prolonging the service life of the catalyst. At present, the general practical operation pressure of the straight-run jet fuel hydrogenation is 1.0-2.0 MPa, the pressure level is low, and the removal of nitrides is not facilitated. Under the condition of the existing device, the pressure grade is constant, the denitrification capability is improved only by increasing the hydrogen partial pressure, and the lifting space is limited.

CN103666546A discloses a liquid-phase hydrofining method for aviation kerosene, which comprises injecting hydrogen into aviation kerosene, and contacting with a catalyst having catalytic hydrogenation function in a hydrogenation reactor under the liquid-phase hydrofining condition, wherein hydrogen is injected into the aviation kerosene through-holes with an average pore diameter of nanometer size. According to the aviation kerosene hydrorefining method of the present invention, hydrogen gas is injected into aviation kerosene through-holes having an average pore diameter of nanometer size, and the hydrogen gas can be highly dispersed and rapidly dissolved in the aviation kerosene even without the aid of a diluent or circulating oil. The method can obtain good hydrofining effect by hydrofining the aviation kerosene, and the content of mercaptan sulfur in the obtained refined oil can be less than 10 mu g/g.

CN104611057A discloses a straight-run kerosene hydrogenation method, wherein a liquid-phase hydrogenation reactor is arranged at the side line of kerosene of an atmospheric tower, the kerosene fraction extracted from a normal line is directly or after heat exchange, mixed with a small amount of pipe network hydrogen in a static mixer and then enters the liquid-phase hydrogenation reactor, and hydrogenation refining reaction is carried out under the action of a hydrogenation catalyst; and the separated liquid product is stripped and taken as a product kerosene to be discharged out of the device. The method mainly utilizes the surplus heat of the atmospheric tower to reduce the energy consumption of the device.

Disclosure of Invention

The invention aims to provide a method for producing jet fuel on the basis of the prior art so as to overcome the problems of harsh operating conditions, poor catalyst stability, high nitrogen content in products, poor product stability and the like when inferior raw oil is processed in the prior art.

The method provided by the invention comprises the steps that the raw kerosene fraction oil and the hydrogen-containing material flow are mixed and then sequentially pass through a first hydrogenation reaction zone and a second hydrogenation reaction zone, the first hydrogenation reaction zone is contacted with a hydrofining catalyst for reaction, and the material after hydrogenation reaction is subjected to gas-liquid separation and liquid-phase material fractionation to obtain a jet fuel component with the alkaline nitrogen content of less than 3 mu g/g and the Saybolt color of more than 25;

the reaction temperature of the first hydrogenation reaction zone is higher than that of the second hydrogenation reaction zone;

the hydrofining catalyst contains a carrier and a hydrogenation active metal component loaded on the carrier, wherein the carrier is alumina and/or silica-alumina;

the hydrofining catalyst is prepared by adopting a method comprising the following steps: (1) impregnating the carrier with a first impregnation liquid, drying and roasting to obtain a semi-finished catalyst, wherein the roasting condition is that the total amount of the semi-finished catalyst is taken as a reference, and the carbon content in the semi-finished catalyst is 0.03-0.5 wt%; (2) impregnating the semi-finished catalyst obtained in the step (1) with a second impregnation solution, and then drying without roasting; the first impregnation liquid is an acidic aqueous solution containing a water-soluble salt of a hydrogenation active metal component and an organic complexing agent, and the second impregnation liquid is an alkaline aqueous solution containing the organic complexing agent.

The raw kerosene fraction oil is kerosene fraction produced by an atmospheric and vacuum distillation process or other processes, or a mixture of kerosene fractions produced by different processes. Preferably, the kerosene fraction feedstock is a normal first-line feedstock obtained by atmospheric distillation of crude oil. Preferably, the sulfur content of the raw kerosene fraction oil is 200-. The method provided by the invention has good adaptability to the property change of the raw material, and is suitable for the kerosene fraction raw oil with low sulfur and nitrogen contents and good properties, and is also suitable for poor kerosene fraction raw oil with high sulfur content, high nitrogen content, high aromatic hydrocarbon content, high naphthenic hydrocarbon content and high acid value.

In the invention, in order to reduce the reaction severity of processing inferior kerosene raw oil and obtain jet fuel with low nitrogen content and stable color stability, two hydrogenation reaction zones connected in series are adopted, and the effluent of the first hydrogenation reaction zone directly enters the second hydrogenation reaction zone without any separation. The reaction conditions in the first hydrogenation reaction zone are relatively harsh, and the hydrodesulfurization and hydrodenitrogenation reactions of the raw kerosene oil are mainly carried out; the reaction conditions in the second hydrogenation reaction zone are relatively mild, as indicated by a lower reaction temperature and a higher space velocity, and in this reaction zone, the color and/or stability of the kerosene is improved.

In one preferred embodiment of the present invention, the reaction conditions of the first hydrogenation reaction zone include: the reaction temperature is 260 ℃ and 400 ℃, and the volume space velocity is 2-8h^-1Hydrogen partial pressure is 1.0-4.0MPa, and the volume ratio of hydrogen to oil is 50-300: 1; preferably, in the first hydrogenation reaction zone: the reaction temperature is 280-380 ℃, and the volume space velocity is 3-6h^-1The volume ratio of hydrogen to oil is 80-200: 1. In the second hydrogenation reaction zone: the reaction temperature is 200 ℃ and 300 ℃, and the volume space velocity is 4-10h^-1Hydrogen partial pressure is 1.0-4.0MPa, and the volume ratio of hydrogen to oil is 50-300: 1; preferably, in the second hydrogenation reaction zone: the reaction temperature is 220 ℃ and 280 ℃, and the volume space velocity is 4-8h^-1The volume ratio of hydrogen to oil is 80-200: 1.

In a preferred aspect, the reaction temperature of the first hydrogenation reaction zone is 10 to 120 deg.C, more preferably 40 to 100 deg.C, higher than the reaction temperature of the second hydrogenation reaction zone.

In one of the preferred embodiments of the present invention, a heat exchanger is provided between the first hydrogenation reaction zone and the second hydrogenation reaction zone, or cold hydrogen and/or cold oil is injected at the inlet of the second hydrogenation reaction zone to adjust the inlet temperature of the second hydrogenation reaction zone.

In the present invention, the first hydrogenation reaction zone and the second hydrogenation reaction zone are filled with the same hydrofining catalyst. The hydrorefining catalyst has high reaction performance, and can simultaneously have good hydrodesulfurization activity and hydrodenitrogenation activity under mild reaction conditions. The hydrofining catalyst contains a carrier and a hydrogenation active metal component loaded on the carrier, wherein the carrier is alumina and/or silica-alumina.

In a preferred case, the content of the hydrogenation metal active component is 5 to 50% by weight in terms of oxide based on the total amount of the hydrorefining catalyst.

Preferably, the hydrogenation metal active component is at least one selected from group VIB metal elements and at least one selected from group VIII metal elements, the group VIB metal elements are further preferably molybdenum and/or tungsten, and the group VIII metal elements are further preferably cobalt and/or nickel; based on the total amount of the hydrofining catalyst, the content of the VIB group metal element is 4-40 wt%, more preferably 8-35 wt%, and the content of the VIII group metal element is 1-10 wt%, more preferably 2-5 wt%, calculated by oxide.

In the invention, the hydrofining catalyst is prepared by adopting a method comprising the following steps: (1) impregnating the carrier with a first impregnation liquid, drying and roasting to obtain a semi-finished catalyst, wherein the roasting condition is that the total amount of the semi-finished catalyst is taken as a reference, and the carbon content in the semi-finished catalyst is 0.03-0.5 wt%; (2) impregnating the semi-finished catalyst obtained in the step (1) with a second impregnation solution, and then drying without roasting; the first impregnation liquid is an acidic aqueous solution containing a water-soluble salt of a hydrogenation active metal component and an organic complexing agent, and the second impregnation liquid is an alkaline aqueous solution containing the organic complexing agent.

According to the present invention, preferably, the calcination conditions in step (1) are such that the amount of carbon in the semi-finished catalyst is 0.04 to 0.4 wt% based on the total amount of the semi-finished catalyst; further preferably, the calcination conditions in step (1) are such that the amount of carbon in the semi-finished catalyst is 0.05 to 0.35 wt% based on the total amount of the semi-finished catalyst.

In a preferable case, the calcination in the step (1) of preparing the hydrorefining catalyst of the present invention is carried out under the condition of introducing an oxygen-containing gas, and the calcination temperature is 350-500 ℃, the calcination time is 0.5-8h, the introduction rate of the oxygen-containing gas per gram of the carrier is 0.2-20L/h, and the oxygen-containing gas is a gas having an oxygen content of not less than 20 vol%. Preferably, the oxygen-containing gas is one or more of air, oxygen and a mixed gas thereof.

On one hand, the oxygen-containing gas is introduced to meet the combustion condition, so that the salt of the active metal component is converted into oxide, and the organic complexing agent is converted into carbon; on the other hand, carbon dioxide and water formed by combustion and other components can be discharged to avoid the deposition on the catalyst to cause vacancy obstruction of the active phase.

The inventor of the invention finds that the complexation impregnation technology of introducing complexing agent and drying at low temperature in the impregnation process can weaken the interaction between active components and carriers, change the metal sulfurization sequence and be beneficial to improving the activity of the catalyst to a certain extent. However, compared with the roasted catalyst, in the process of low-temperature drying and no high-temperature roasting adopted in the complexing and impregnating technology, although the complexing agent can play a role in regulating the metal sulfurization sequence and helping the metal to disperse on the surface of the carrier, the metal compound still exists on the surface of the carrier in the form of metal salt, the acting force of the active component and the carrier is weak, the metal is easy to aggregate and grow during sulfurization, and therefore, the intrinsic activity is not obviously increased. The method of carrying out high-temperature roasting after the first impregnation, then carrying out the second impregnation of the complexing agent, drying and not roasting can improve the interaction between the metal and the carrier to prevent the metal from aggregating and growing up in the vulcanization process, and can adjust the metal vulcanization sequence, and the prepared catalyst has higher activity.

The inventor of the present invention further found through research that the catalyst is prepared by a two-step impregnation method, the first impregnation and the second impregnation are used for introducing a hydrogenation metal active component and an organic complexing agent, respectively, and the organic complexing agent is added in the first impregnation and is converted into carbon through roasting, so that the activity of the catalyst can be significantly improved. Presumably, the reason for this is that the presence of the organic complexing agent added during the first impregnation hinders the aggregation of the active metal during the calcination, making it more uniformly dispersed; meanwhile, the roasting after the first step of dipping can convert metal compounds into metal oxides and convert organic complexing agents into carbon, so that the acting force between the active metal and the carrier is more appropriate, and the vulcanization process of the catalyst is facilitated. The organic complexing agent added in the second step of dipping process can change the metal sulfurization sequence, further effectively prevent the aggregation of active metal in the sulfurization process, improve the metal dispersity, and be more beneficial to forming II-type active phases with higher activity and forming more active centers, thereby further improving the activity of the catalyst. Therefore, the technology can effectively overcome the technical defects of the conventional impregnation method and the existing complex impregnation method.

According to the present invention, preferably, the molar ratio of the organic complexing agent in the step (1) of preparing the hydrofining catalyst to the metal active component is 0.03-2: 1, preferably 0.08-1.5: 1.

According to the present invention, it is preferable that the molar ratio of the organic complexing agent in the step (1) and the step (2) for preparing the hydrofining catalyst is 1: 0.25 to 4, preferably 1: 0.5-2.

In the present invention, the organic complexing agent in the step (1) and the organic complexing agent in the step (2) for preparing the hydrofining catalyst may be the same or different, and preferably, the organic complexing agent is selected from one or more of oxygen-containing and/or nitrogen-containing organic substances.

The oxygen-containing organic substance is preferably one or more of organic alcohol and organic acid.

The organic alcohol is preferably a dihydric or higher polyhydric alcohol, more preferably a polyhydric alcohol having 2 to 6 carbon atoms or an oligomer or polymer thereof, such as one or more of ethylene glycol, glycerol, polyethylene glycol, diethylene glycol, and butanediol. The molecular weight of the polyethylene glycol is preferably 200-1500.

The organic acid is preferably a compound containing one or more COOH groups and C2-C7, and specifically can be one or more of acetic acid, maleic acid, oxalic acid, nitrilotriacetic acid, 1, 2-cyclohexanediaminetetraacetic acid, citric acid, tartaric acid and malic acid.

The nitrogen-containing organic matter is preferably one or more of organic amine and organic ammonium salt.

The organic amine is preferably a compound containing one or more NH groups and having a carbon number of from 2 to 7, and can be a primary amine, a secondary amine or a tertiary amine, and particularly preferably ethylenediamine.

The organic ammonium salt is preferably EDTA or a substitute thereof.

In particular, the organic complexing agent is particularly preferably one or more of ethylene glycol, glycerol, polyethylene glycol (molecular weight is preferably 200-.

In a preferred case, the organic complexing agent in the step (1) of preparing the hydrofining catalyst is selected from one or more of organic acids, and more preferably, the organic complexing agent in the step (1) is selected from one or more of fatty acids of C2-C7. By using an organic acid as the organic complexing agent in step (1), a hydrorefining catalyst having higher activity can be obtained.

In a preferable case, the organic complexing agent in the hydrofining catalyst preparation step (2) is selected from one or more of organic amine and organic ammonium salt, and more preferably, the organic complexing agent in the step (2) is selected from one or more of organic amine and organic ammonium salt of C2-C7. By using organic amine and organic ammonium salt as the organic complexing agent in the step (2), the hydrofining catalyst with higher activity can be obtained.

In the present invention, the drying conditions are not particularly limited, and may be various drying conditions commonly used in the art, and the drying conditions in the step (1) and the step (2) may be the same or different.

Preferably, the drying temperature in the hydrofining catalyst preparation step (1) is 100-250 ℃ and the time is 1-12 h.

Preferably, the drying temperature in the hydrofining catalyst preparation step (2) is 100-200 ℃, and the time is 1-12 h.

According to the present invention, it is preferable that the concentration of the water-soluble salt of the hydrogenation metal active component is 0.2 to 8mol/L, preferably 0.2 to 5mol/L, and more preferably 0.2 to 2mol/L, in terms of the metal element. The concentrations herein are the respective concentrations of the water-soluble salts of the various hydrogenation metal active components, not the total concentration.

The water-soluble salt of the hydrogenation metal active component can be various water-soluble compounds with the solubility meeting the loading requirement or capable of forming the hydrogenation metal active component with the solubility meeting the requirement in water in the presence of a cosolvent, and can be one or more of nitrate, chloride, sulfate and carbonate, and is preferably nitrate.

According to the invention, the first impregnation solution is an acidic aqueous solution, for example with a pH value of 2 to 6, preferably with a pH value of 3 to 5, and the second impregnation solution is a basic aqueous solution, for example with a pH value of 7 to 14, preferably with a pH value of 8 to 11.

According to the present invention, the aqueous solution of the hydrorefining catalyst preparation step (1) may further contain various cosolvents commonly used in the art to improve the solubility of the group VIB metal element-containing compound and the group VIII metal element-containing compound in water; or stabilizing the aqueous solution against precipitation. The co-solvent may be any of various materials commonly used in the art to achieve the above-described functions, and is not particularly limited. For example, the cosolvent may be one or more of phosphoric acid, citric acid and ammonia water.

According to the method provided by the invention, the jet fuel component with the alkaline nitrogen content less than 3 mug/g and the Saybolt color greater than 25 can be obtained; preferably the resulting jet fuel component has a nitrogen content of less than 3 μ g/g, more preferably less than 1 μ g/g.

The method provided by the invention can be used for treating inferior high-sulfur high-nitrogen kerosene fraction and producing jet fuel components with nitrogen content or alkaline nitrogen content lower than 3 mu g/g, Saybolt color larger than 25 and good thermal stability under relatively mild conditions. In addition, the whole catalyst system has better stability, and the running period of the device is obviously prolonged.

Detailed Description

The invention is further described below by way of examples, but is not limited thereby.

The following examples are provided to illustrate the practice and advantages of the present invention in more detail, and are not to be construed as limiting the scope of the invention.

In the following examples, the contents of the respective elements in the catalyst were analyzed and measured by a 3271E type X-ray fluorescence spectrometer, manufactured by japan food and electronics industries co. The carbon content in the catalyst semi-finished product was analyzed and measured using an EMIA-320V carbon sulfur analyzer manufactured by HORIBA, Japan.

In the comparative example, the hydrofining catalyst adopts a commercial RSS-2 catalyst and is produced by medium petrochemical catalyst companies.

In the examples, hydrofining catalysts S1, S2 and S3 were used as hydrofining catalysts and were prepared by the following methods, respectively:

examples of production of alumina

2000 g of aluminum hydroxide powder (dry rubber powder produced by catalyst factory of Changling division, 72 wt% of dry base) is weighed, extruded into butterfly-shaped strips with the circumscribed circle diameter of 1.3 mm by a strip extruder, the wet strips are dried for 4 hours at 120 ℃, and are roasted for 3 hours at 600 ℃ to obtain the carrier Z1. The Z1 carrier had a radial crush strength of 29.5N/mm, a water absorption of 0.85 ml/g, a pore volume of 0.67ml/g, and a specific surface area of 275m²/g。

The hydrofinishing catalyst S1 used in the examples was prepared using the following method:

40 g of molybdenum trioxide, 19 g of basic cobalt carbonate, 15 g of phosphoric acid and 20 g of citric acid are respectively weighed and put into 140 g of deionized water, heating, stirring and dissolving are carried out, so as to obtain a clear impregnation solution, and the pH value is measured to be 3.5. Soaking 200 g of alumina carrier Z1 in the solution for 2 hours by adopting a saturated soaking method, then drying the alumina carrier for 2 hours at 120 ℃, then roasting the alumina carrier under the condition of introducing air flow, wherein the roasting temperature is 400 ℃, the time is 2 hours, and the air introduction rate is 2 liters/hour relative to each gram of carrier, so that a semi-finished catalyst Z1-S1 is obtained, and the carbon content of Z1-S1 is shown in Table 1; adding 5 g of EDTA into 150 g of deionized water, adding a proper amount of ammonia water to adjust the pH value of the solution to 10.5, stirring to obtain a clear solution, soaking Z1-S1 in the solution for 2 hours by adopting a saturated soaking method, and then drying for 3 hours at 110 ℃ to obtain the hydrofining catalyst S1. The content of the hydrogenation metal active component in terms of oxide based on the total amount of S1 is shown in Table 1.

The hydrofinishing catalyst S2 used in the examples was prepared using the following method:

40 g of molybdenum trioxide, 21 g of basic nickel carbonate, 13 g of phosphoric acid and 30 g of citric acid are respectively weighed and put into 140 g of deionized water, heating and stirring are carried out to dissolve the molybdenum trioxide, the basic nickel carbonate, the phosphoric acid and the citric acid to obtain a clear impregnation solution, and the pH value is measured to be about 4.0. Soaking 200 g of the carrier Z1 in the solution for 2 hours by adopting a saturated soaking method, then drying the carrier for 2 hours at 150 ℃, then roasting the carrier under the condition of introducing air flow, wherein the roasting temperature is 360 ℃, the time is 3 hours, and the air introduction rate is 10 liters/hour relative to each gram of the carrier, so that a semi-finished catalyst Z1-S2 is obtained, and the carbon content of Z1-S2 is shown in Table 1; adding 30 g of citric acid into 150 g of deionized water, stirring to obtain a clear solution, and adding a proper amount of ammonia water to adjust the pH value to 10.5. The solution was impregnated with Z1-S2 by a saturation impregnation method for 2 hours, and then dried at 150 ℃ for 3 hours to obtain a hydrorefining catalyst S2. The content of the hydrogenation metal active component in terms of oxide based on the total amount of S2 is shown in Table 1.

The hydrofinishing catalyst S3 used in the examples was prepared using the following method:

respectively weighing 30 g of nickel nitrate, 55 g of ammonium metatungstate, 10g of magnesium nitrate, 15 g of phosphoric acid and 10g of diethylene glycol, putting the nickel nitrate, the ammonium metatungstate, the magnesium nitrate, the phosphoric acid and the diethylene glycol into 140 g of deionized water, stirring and dissolving to obtain a clear solution, measuring the pH value of the solution to be 3.0, soaking 200 g of the alumina carrier Z1 by using a saturated soaking method for 2 hours, then drying the alumina carrier Z1 for 2 hours at 120 ℃, roasting the alumina carrier Z for 4 hours at the roasting temperature of 450 ℃ under the condition of introducing air flow, wherein the air introduction rate is 0.3 liter/hour relative to each gram of the carrier, so that a semi-finished catalyst Z1-S3 is obtained, and the carbon content of Z1-S3 is shown in Table; 10g of ethylenediamine is added into 150 g of deionized water, the mixture is stirred to obtain a clear solution, and a proper amount of ammonia solution is added to adjust the pH value to 9.5. The hydrogenation catalyst S3 was obtained by impregnating Z1-S3 with the above solution for 2 hours by saturation impregnation and then drying at 120 ℃ for 6 hours. The content of the hydrogenation metal active component in terms of oxide based on the total amount of S3 is shown in Table 1.

In the comparative example, hydrorefining catalysts D1 and D2 were used as hydrorefining catalysts and were prepared by the following methods, respectively:

the hydrofinishing catalyst D1 used in the comparative example was prepared by the following method:

the same preparation method as that of the hydrogenation catalyst S1 was adopted, except that the prepared hydrogenation catalyst S1 was calcined at 400 ℃ for 3 hours to obtain the hydrogenation catalyst D1, and the content of the hydrogenation metal active component in the hydrogenation catalyst D1 was shown in Table 1 in terms of oxide based on the total amount of D1.

The hydrofinishing catalyst D2 used in the comparative example was prepared by the following method:

30 g of nickel nitrate, 55 g of ammonium metatungstate, 15 g of phosphoric acid and 10g of diethylene glycol are respectively weighed and put into 140 g of deionized water, stirred and dissolved to obtain a clear solution, 200 g of alumina carrier Z1 is soaked in the clear solution by adopting a saturated soaking method for 2 hours, and then dried for 2 hours at 120 ℃ to obtain the hydrogenation catalyst D2. The content of the hydrogenation metal active component, calculated as the oxide, based on the total amount of D2, is shown in table 1.

TABLE 1 catalyst Properties

The properties of the raw oils used in the examples and comparative examples are shown in Table 2.

TABLE 2 Properties of the feed oils

	Raw oil A	Raw oil B	Raw oil C
				Density (20 ℃ C.)/g.cm^-3	0.8074	0.7967	0.7862
Total sulfur content/μ g/g	2000	3200	780
				Mercaptan sulfur content/. mu.g/g	108	120	54
Total nitrogen content/. mu.g/g	44	64	24
				Basic nitrogen content/. mu.g/g	18	24	<1
Distillation range (ASTM D-86), deg.C	161～251	177～254	156～245

Example 1

Taking a high-nitrogen kerosene fraction as raw material oil A, pressurizing the raw material oil A, mixing the raw material oil A with a hydrogen-containing material flow, then feeding the mixture into a hydrogenation reactor, sequentially passing through a first hydrogenation reaction zone and a second hydrogenation reaction zone, and contacting with a hydrofining catalyst S1 for reaction, wherein the hydrogen partial pressure at the inlet of the reactor is 1.6MPa, the reaction temperature of the first hydrogenation reaction zone is 340 ℃, the reaction temperature of the second hydrogenation reaction zone is 240 ℃, and the liquid hourly volume space velocity of the first hydrogenation reaction zone is 3.0h^-1The liquid hourly space velocity of the second hydrogenation reaction zone was 6.0h^-1The hydrogen-oil volume ratio of the first hydrogenation reaction zone and the second hydrogenation reaction zone is 100.

And performing gas-liquid separation on the effluent of the hydrogenation reactor in a high-pressure separator, desulfurizing the gas-phase material flow obtained by separation in the high-pressure separator, circulating the gas-phase material flow back to the inlet of the reactor, allowing the liquid-phase material flow obtained by separation in the high-pressure separator to enter a low-pressure separator for further gas-liquid separation, and fractionating the liquid-phase material flow obtained by the low-pressure separator in a fractionating tower to obtain jet fuel components. The jet fuel components main properties are shown in table 3.

Example 2

Taking a high-sulfur high-nitrogen kerosene fraction as raw material oil B, pressurizing the raw material oil B, mixing the raw material oil B with hydrogen-containing material flow, then feeding the mixture into a hydrogenation reactor, sequentially passing through a first hydrogenation reaction zone and a second hydrogenation reaction zone, and contacting with a hydrofining catalyst S2 for reaction, wherein the hydrogen partial pressure at the inlet of the reactor is 3.2MPa, the reaction temperature of the first hydrogenation reaction zone is 360 ℃, the reaction temperature of the second hydrogenation reaction zone is 260 ℃, and the liquid hourly volume space velocity of the first hydrogenation reaction zone is 4.0h^-1The liquid hourly space velocity of the second hydrogenation reaction zone was 8.0h^-1The hydrogen-oil volume ratio of the first hydrogenation reaction zone and the second hydrogenation reaction zone is 100.

The vapor-liquid separation and liquid phase stream fractionation schemes were the same as in example 1, with the jet fuel components having the main properties shown in table 3.

Example 3

Taking a kerosene fraction as raw oil C, pressurizing the raw oil C, mixing the raw oil C with a hydrogen-containing material flow, then feeding the mixture into a hydrogenation reactor, sequentially passing through a first hydrogenation reaction zone and a second hydrogenation reaction zone, and contacting with a hydrofining catalyst S3 for reaction, wherein the hydrogen partial pressure at the inlet of the reactor is 1.6MPa, the reaction temperature of the first hydrogenation reaction zone is 300 ℃, the reaction temperature of the second hydrogenation reaction zone is 220 ℃, and the liquid hourly volume space velocity of the first hydrogenation reaction zone is 3.0h^-1The liquid hourly space velocity of the second hydrogenation reaction zone was 8.0h^-1The hydrogen-oil volume ratio of the first hydrogenation reaction zone and the second hydrogenation reaction zone was 60.

TABLE 3

Comparative example 1

Taking a high-nitrogen kerosene fraction as raw material oil A, pressurizing the raw material oil A, mixing the raw material oil A with hydrogen-containing material flow, then feeding the mixture into a hydrogenation reactor, contacting with a hydrofining catalyst S1 for reaction, wherein the hydrogen partial pressure at the inlet of the reactor is 1.6MPa, the reaction temperature is 340 ℃, and the liquid hourly volume space velocity is 3.0h^-1Hydrogen to oil volume ratio 100.

The vapor-liquid separation and liquid phase stream fractionation schemes were the same as in example 1, with the jet fuel components having the main properties shown in table 4.

Comparative example 2

Taking a high-nitrogen kerosene fraction as raw material oil A, pressurizing the raw material oil A, mixing the raw material oil A with a hydrogen-containing material flow, then feeding the mixture into a hydrogenation reactor, sequentially passing through a first hydrogenation reaction zone and a second hydrogenation reaction zone, and contacting with a hydrofining catalyst D1 for reaction, wherein the hydrogen partial pressure at the inlet of the reactor is 1.6MPa, the reaction temperature of the first hydrogenation reaction zone is 340 ℃, the reaction temperature of the second hydrogenation reaction zone is 240 ℃, and the liquid hourly volume space velocity of the first hydrogenation reaction zone is 3.0h^-1The liquid hourly space velocity of the second hydrogenation reaction zone was 6.0h^-1The hydrogen-oil volume ratio of the first hydrogenation reaction zone and the second hydrogenation reaction zone is 100.

Comparative example 3

Taking a high-nitrogen kerosene fraction as raw material oil A, pressurizing the raw material oil A, mixing the raw material oil A with a hydrogen-containing material flow, then feeding the mixture into a hydrogenation reactor, sequentially passing through a first hydrogenation reaction zone and a second hydrogenation reaction zone, and contacting with a hydrofining catalyst D2 for reaction, wherein the hydrogen partial pressure at the inlet of the reactor is 1.6MPa, the reaction temperature of the first hydrogenation reaction zone is 340 ℃, the reaction temperature of the second hydrogenation reaction zone is 240 ℃, and the liquid hourly volume space velocity of the first hydrogenation reaction zone is 3.0h^-1The liquid hourly space velocity of the second hydrogenation reaction zone was 6.0h^-1The hydrogen-oil volume ratio of the first hydrogenation reaction zone and the second hydrogenation reaction zone is 100.

Comparative example 4

Taking a high-nitrogen kerosene fraction as raw material oil A, pressurizing the raw material oil A, mixing the raw material oil A with hydrogen-containing material flow, then feeding the mixture into a hydrogenation reactor, sequentially passing through a first hydrogenation reaction zone and a second hydrogenation reaction zone, and contacting with a hydrofining catalyst RSS-2 for reaction, wherein the hydrogen partial pressure at the inlet of the reactor is 1.6MPa, the reaction temperature of the first hydrogenation reaction zone is 340 ℃, the reaction temperature of the second hydrogenation reaction zone is 240 ℃, and the liquid hourly volume space velocity of the first hydrogenation reaction zone is 3.0h^-1The liquid hourly space velocity of the second hydrogenation reaction zone was 6.0h^-1The hydrogen-oil volume ratio of the first hydrogenation reaction zone and the second hydrogenation reaction zone is 100.

TABLE 4

As can be seen from the results in tables 3-4, (1) by adopting the method provided by the invention, the basic nitrogen content of the high-nitrogen kerosene raw oil can be reduced to be below 3.0 mu g/g by treating the high-nitrogen kerosene raw oil under the mild hydrogenation condition, and the requirement of jet fuel on color stability is met. (2) The method provided by the invention has strong adaptability to the kerosene raw oil and can treat raw oil with different properties.

Claims

1. A method for producing jet fuel is characterized in that kerosene fraction raw oil and hydrogen-containing material flow are mixed and then sequentially pass through a first hydrogenation reaction zone and a second hydrogenation reaction zone, the first hydrogenation reaction zone is contacted with a hydrofining catalyst for reaction, and after gas-liquid separation and liquid phase material fractionation are carried out on the material after hydrogenation reaction, a jet fuel component with the alkaline nitrogen content of less than 3 mu g/g and the Saybolt color of more than 25 is obtained;

2. The process as claimed in claim 1, characterized in that the sulfur content of the kerosene fraction feedstock oil is 200-5000. mu.g/g, preferably not more than 3500. mu.g/g, and the nitrogen content is 10-100. mu.g/g.

3. The method according to claim 1 or 2, wherein the kerosene fraction feedstock is a normal first-line feedstock obtained by atmospheric distillation of crude oil.

4. The process of claim 1, wherein in the first hydrogenation reaction zone: the reaction temperature is 260 ℃ and 400 ℃, and the volume space velocity is 2-8h^-1Hydrogen partial pressure is 1.0-4.0MPa, and the volume ratio of hydrogen to oil is 50-300: 1; preferably, in the first hydrogenation reaction zone: the reaction temperature is 280-380 ℃, and the volume space velocity is 3-6h^-1The volume ratio of hydrogen to oil is 80-200: 1;

in the second hydrogenation reaction zone: the reaction temperature is 200 ℃ and 300 ℃, and the volume space velocity is 4-10h^-1Hydrogen partial pressure is 1.0-4.0MPa, and the volume ratio of hydrogen to oil is 50-300: 1; preferably, in the second hydrogenation reaction zone: the reaction temperature is 220 ℃ and 280 ℃, and the volume space velocity is 4-8h^-1The volume ratio of hydrogen to oil is 80-200: 1.

5. The process of claim 1 or 4, wherein the reaction temperature of the first hydrogenation reaction zone is 10 to 120 ℃, preferably 40 to 100 ℃ higher than the reaction temperature of the second hydrogenation reaction zone.

6. A method according to claim 1, wherein the resulting jet fuel component has a nitrogen content of less than 3 μ g/g, preferably less than 1 μ g/g.

7. The process according to claim 1, wherein the calcination conditions in the hydrorefining catalyst preparation step (1) are such that the amount of char in the semi-finished catalyst is from 0.04 to 0.4% by weight, based on the total amount of the semi-finished catalyst.

8. The process as claimed in claim 1, wherein the calcination in the hydrorefining catalyst preparation step (1) is carried out under the condition of introducing an oxygen-containing gas, and the calcination temperature is 350 ℃ and 500 ℃ and the calcination time is 0.5 to 8 hours, the introducing rate of the oxygen-containing gas per gram of the carrier is 0.2 to 20 liters/hour, and the oxygen-containing gas is a gas having an oxygen content of not less than 20% by volume.

9. The method according to claim 1, wherein the molar ratio of the organic complexing agent to the metal active component in the hydrorefining catalyst preparation step (1) is 0.03-2: 1.

10. the method of claim 1, wherein the hydrofinishing catalyst is prepared by mixing the organic complexing agent in the step (1) and the organic complexing agent in the step (2) in a molar ratio of 1: 0.25-4.

11. The method according to claim 1 or 10, wherein the hydrofining catalyst preparation step (1) is the same as or different from the organic complexing agent in step (2), and the organic complexing agent is selected from one or more of oxygen-containing organic substances and/or nitrogen-containing organic substances, the oxygen-containing organic substances are selected from one or more of organic alcohol and organic acid, and the nitrogen-containing organic substances are selected from one or more of organic amine and organic ammonium salt.

12. The method according to claim 1, 10 or 11, wherein the organic complexing agent in the step of preparing the hydrofining catalyst (1) is one or more of organic acids with 2-7 carbon atoms;

and (3) preparing the hydrofining catalyst, wherein the organic complexing agent in the step (2) is one or more of organic amine with the carbon atom number of 2-7 and organic ammonium salt.

13. The process of claim 1, wherein the hydrogenation metal active component is present in an amount of 5 to 50 wt.% on an oxide basis, based on the total amount of hydrofinishing catalyst.

14. The process according to claim 1 or 13, characterized in that the hydrogenation metal active component is at least one element selected from group VIB metals, preferably molybdenum and/or tungsten, and at least one element selected from group VIII metals, preferably cobalt and/or nickel; based on the total amount of the hydrofining catalyst, the content of the VIB group metal element is 4-40 wt%, preferably 8-35 wt%, and the content of the VIII group metal element is 1-10 wt%, preferably 2-5 wt%, calculated by oxide.