A method for preparing jet fuel components by hydrogenating oil and fat raw materials

Abstract

The present invention relates to a method for preparing jet fuel components by hydrogenating oil and fat raw materials. After being treated with hydrogenation and purified, the oil and fat raw materials enter a hydrocracking unit for a hydrocracking reaction. The reaction effluent of the hydrocracking unit contacts a hydroisomerization catalyst for a reaction. After the reaction effluent of the hydroisomerization unit is subjected to gas-liquid separation, the obtained liquid phase stream is fractionated to obtain naphtha and jet fuel components. The present invention can obtain high-quality jet fuel components in maximum quantity, has low energy consumption, and effectively improves the economic benefits of the device.

Description

Technical Field

[0001] The invention relates to the technical field of oil and fat raw material processing, and in particular to a method for preparing jet fuel components by hydrogenating oil and fat raw materials. Background Art

[0002] As the supply of traditional fossil energy becomes tighter, the pressure to reduce carbon dioxide emissions is increasing. How to effectively reduce carbon dioxide emissions while increasing fuel supply is an important issue facing the oil refining industry. The development of biomass fuel is considered to be one of the effective means to solve this problem. Especially for the aviation transportation industry, the use of biomass jet fuel is considered to be the most important way to solve the industry's carbon emissions.

[0003] The production of jet fuel using oil as raw material usually adopts a two-step hydrogenation process. First, the oil raw material is hydrogenated to obtain hydrocarbon compounds; then the hydrocarbon compounds are hydrogenated and converted to prepare jet fuel components that meet jet fuel standards.

[0004] US20090158637A1 discloses a method for producing aviation fuel from renewable raw materials such as vegetable oils and animal fats and oils. The method includes treating the renewable raw materials by hydrogenation and deoxygenation to provide normal paraffins having about 8 to about 24 carbon atoms. At least some of the normal paraffins are isomerized to improve cold flow properties. At least a portion of the paraffins are selectively cracked to provide paraffins that meet the specifications of different aviation fuels such as JP-8.

[0005] CN103059900A discloses a method for preparing jet fuel, wherein the method comprises: (1) under hydrodeoxygenation conditions, vegetable oil and / or animal fat, hydrogen and a hydrodeoxygenation catalyst are contacted to obtain C8-C24 normal alkanes; (2) under hydroisomerization conditions, the C8-C24 normal alkanes, hydrogen and a hydroisomerization catalyst are contacted; (3) under hydrorefining conditions, the product after the contact in step (2), hydrogen and a hydrorefining catalyst are contacted and fractionated to obtain jet fuel. The jet fuel prepared by the method of the present invention is almost entirely composed of saturated alkanes, and has stable properties, meeting the requirements of No. 3 jet fuel.

[0006] CN102124080A discloses a method for producing hydrocarbons using biomaterials, and hydrocarbons and fuels thereof, wherein the feed is subjected to hydrogenation saturation reaction, deoxygenation reaction and alkane isomerization reaction to generate reaction products, the liquid hydrocarbon components are distilled, the target hydrocarbon products are collected, and the liquid hydrocarbon components or the target hydrocarbon products are recycled to the reaction step; wherein the catalyst in the reaction step is a loaded catalyst of a ten-membered ring one-dimensional pore molecular sieve loaded with a Group VIII metal.

[0007] CN103059930A provides a method for preparing jet fuel, wherein a heavy fraction with a boiling point of more than 260° C. is mixed with normal alkanes of C8-C24 to obtain a mixture, and then subjected to hydrogenation isomerization and hydrogenation refining, and the reaction product is fractionated to obtain jet fuel and the heavy fraction with a boiling point of more than 260° C. In the method, a heavy fraction cyclic conversion method is used to improve the yield of jet fuel.

[0008] The above-mentioned prior art has the technical problem of low jet fuel yield. Summary of the invention

[0009] The invention aims to solve the technical problem that the jet fuel yield is relatively low when the prior art processes renewable raw materials to produce jet fuel.

[0010] The present invention provides a method for preparing jet fuel components by hydrogenating oil and fat raw materials, comprising:

[0011] (1) A hydroprocessing unit, in which the oil and fat raw material is contacted with a hydroprocessing catalyst in the presence of hydrogen to react,

[0012] (2) A purification treatment unit, in which the reaction effluent of the hydroprocessing unit is subjected to gas-liquid separation, and the resulting liquid phase stream is subjected to gas stripping and drying to obtain purified liquid hydrocarbons.

[0013] (3) a hydrocracking unit, wherein the purified liquid hydrocarbon obtained from the purification treatment unit is contacted with a hydrocracking catalyst in the presence of hydrogen for reaction, wherein the hydrocracking catalyst comprises a carrier and an active metal component, wherein the carrier comprises alumina and silica-alumina, wherein the content of the alumina is 20 to 80% by weight, and the content of the silica-alumina is 80 to 20% by weight, based on the carrier; and the active metal component is one or more selected from Group VIII metals, wherein the content of the active metal component is 0.1 to 5% by weight, calculated as oxide, based on the total weight of the hydrocracking catalyst; and the conversion rate of the fraction having a temperature of >270°C in the hydrocracking unit is controlled to be 50% to 90%;

[0014] (4) a hydroisomerization unit, wherein the reaction effluent of the hydrocracking unit is contacted with a hydroisomerization catalyst for reaction, wherein the hydroisomerization catalyst comprises a carrier and an active metal component, wherein the carrier comprises a mesoporous molecular sieve and alumina, and the active metal component is selected from one or more of cobalt, nickel, palladium, platinum, molybdenum and tungsten. Based on the total weight of the hydroisomerization catalyst, the content of the mesoporous molecular sieve is 20 to 80% by weight, the content of alumina is 15 to 75% by weight, and the content of the active metal component is 0.2 to 5% by weight, calculated as oxide, and the sum of the contents of the above components is 100%;

[0015] After the reaction effluent of the hydroisomerization unit is separated into gas and liquid, the resulting liquid phase stream is fractionated to obtain naphtha and jet fuel components.

[0016] In the present invention, the oil raw materials include one or more of various animal and plant oils and restaurant waste oils.

[0017] The plant and animal oils include plant oils and animal fats, raw materials containing glycerides and free fatty acids, and fatty acid methyl esters or fatty acid ethyl esters prepared by plant oils and / or animal fats through an ester exchange method. The glycerides include triglycerides, diglycerides and monoglycerides. The plant oils include but are not limited to one or more of soybean oil, rapeseed oil, cottonseed oil, corn oil, rice bran oil, sunflower oil, peanut oil, castor oil, sesame oil, prickly ash seed oil, tea oil, coconut oil, olive oil, Pistacia chinensis oil, palm oil, tung oil, jatropha oil, rosin oil and Chinese tallow oil.

[0018] The waste cooking oil is the waste oil that is no longer suitable for consumption and is produced during the processing and consumption of animal and plant oils. It includes fatty acids and acidified oils produced in the process of producing edible oil from oilseeds; various types of waste cooking oil such as frying oil, kitchen oil, and sewage oil produced in the use of edible oil by households, hotels, catering industries, and food production companies; animal fat produced as a byproduct in meat production and processing, and edible oil that has exceeded its shelf life.

[0019] In the hydroprocessing unit of step (1), the oil and fat feedstock is contacted with a hydroprocessing catalyst in the presence of hydrogen, and mainly undergoes reactions such as hydrodeoxygenation, olefin saturation, hydrodesulfurization and hydrodenitrogenation to obtain a reaction effluent containing water, hydrogen sulfide and ammonia.

[0020] In one embodiment of the present invention, the hydroprocessing catalyst comprises a metal active component and a carrier, the carrier is selected from one or more of aluminum oxide, silicon oxide, zirconium oxide, and titanium oxide, the metal active component is at least one selected from the VIB group metal element and at least one selected from the VIII group metal element, the VIB group metal element is molybdenum and / or tungsten, and the VIII group metal element is cobalt and / or nickel; based on the total weight of the hydroprocessing catalyst, the content of the metal active component is 5 to 50 weight % in terms of oxide.

[0021] In a preferred case, based on the total weight of the hydroprocessing catalyst, the content of the VIB group metal element is 4-40% by weight, and the content of the VIII group metal element is 1-10% by weight, calculated as oxide; and the metal active component contains cobalt and molybdenum.

[0022] More preferably, based on the total weight of the hydroprocessing catalyst, the content of the VIB group metal element is 8 to 35% by weight, and the content of the VIII group metal element is 2 to 5% by weight, calculated as oxide.

[0023] In one embodiment of the present invention, the reaction conditions of the hydroprocessing unit are: hydrogen partial pressure 1.0-15.0 MPa, reaction temperature 150-450°C, liquid hourly volume space velocity 0.1-10 h -1 , Hydrogen to oil volume ratio 300-2000;

[0024] The preferred reaction conditions of the hydroprocessing unit are: hydrogen partial pressure 3.0-10.0 MPa, reaction temperature 250-400°C, liquid hourly volume space velocity 0.5-5.0 h -1 , hydrogen-oil volume ratio: 500~1500.

[0025] According to the method provided by the present invention, the hydroprocessing catalyst is preferably used as a hydroprocessing catalyst after being sulfurized. In one embodiment of the present invention, in order to maintain the sulfurized form of the catalyst, sulfur is supplemented in the oil and fat raw material, or sulfur is added to the circulating hydrogen.

[0026] In one embodiment of the present invention, the oil and fat raw material contains a vulcanizing agent, and the mass fraction of the vulcanizing agent is 0.01% to 0.5% by weight. The vulcanizing agent can be various sulfur-containing substances that can be gasified under hydrodeoxygenation conditions and vulcanize the hydroprocessing catalyst. Preferably, the vulcanizing agent is one or more of hydrogen sulfide, carbon disulfide, dimethyl disulfide, methyl sulfide, n-butyl sulfide and thiophene. Further, in order to reduce the influence of water generated during the hydrodeoxygenation process on the catalyst and reduce the temperature rise caused by the reaction heat, the product after hydrotreatment can be used as a diluent for the feed, that is, the product after hydrotreatment is partially returned and mixed with the feed to enter the hydroprocessing reactor to contact the hydroprocessing catalyst. For the present invention, the volume ratio of the return amount of the hydroprocessed product to the feed amount is preferably 2 to 10:1. In step (1), the oxygen contained in the oil and fat raw material is removed in the form of water, carbon dioxide and carbon monoxide; the heteroatoms such as sulfur and nitrogen contained are hydrogenated and removed in the form of hydrogen sulfide and ammonia.

[0027] In one embodiment of the present invention, the reaction effluent of the hydroprocessing unit obtained in step (1) enters the purification processing unit in step (2), and is successively separated into gas and liquid by a high-pressure separator and a low-pressure separator to obtain a gas phase stream and a liquid phase stream. The obtained liquid phase stream enters a high-pressure stripping tower for gas stripping, and the gas stripping gas is selected from one or more of hydrogen, nitrogen, and water vapor. The liquid phase stream after gas stripping is dried in a dryer to obtain purified liquid hydrocarbons.

[0028] In one embodiment of the present invention, in the purified liquid hydrocarbon obtained in step (2), the mass fraction of alkanes with a carbon number of 15 to 18 is not less than 90%, the hydrogen sulfide content is not more than 5 mg / kg, and the water content is not more than 300 mg / kg.

[0029] In step (3) of the present invention, the purified liquid hydrocarbon obtained by the purification treatment unit is contacted with a hydrocracking catalyst to carry out a hydrocracking reaction, so that the alkanes in the purified liquid hydrocarbon are selectively cracked into jet fuel components, and part of the naphtha fraction is produced as a by-product; the mass yield of the jet fuel components obtained by the present invention can reach more than 60%.

[0030] In order to obtain the maximum amount of high-quality jet fuel components, in a preferred case, the conversion rate of the fraction >270°C in the hydrocracking unit is controlled to be 50% to 90%, more preferably 60% to 80%;

[0031] Conversion rate of fraction >270°C = 100% * (mass fraction of fraction >270°C in purified liquid hydrocarbons - mass fraction of fraction >270°C in hydrocracking unit reaction products) / mass fraction of fraction >270°C in purified liquid hydrocarbons.

[0032] If the hydrocracking reaction unit controls the conversion rate of the fraction >270℃ too low, the heavy fraction content in the product will be high, which will lead to a high colloid content in the jet fuel component. The heavy fraction needs to be cut out, and the maximum amount of jet fuel components cannot be obtained. Moreover, the product fraction quality index cannot meet the jet fuel quality requirements. If the hydrocracking reaction unit controls the conversion rate of the fraction >270℃ too high, not only will the jet fuel component yield be reduced, but also the hydrogen consumption of the device will increase significantly, and the device product plan will be uneconomical and unreasonable.

[0033] In one embodiment of the present invention, the carrier of the hydrocracking catalyst contains alumina and silica-alumina, and the content of alumina is 25-75% by weight and the content of silica-alumina is 75-25% by weight based on the carrier.

[0034] In one embodiment of the present invention, the alumina is an alumina whose pore volume with pore diameter less than 60 angstroms accounts for more than 30% of the total pore volume; preferably, the alumina is an alumina whose pore volume with pore diameter less than 60 angstroms accounts for more than 25% of the total pore volume.

[0035] In one embodiment of the present invention, the aluminum oxide is selected from one or more transition phase aluminum oxides selected from γ, η, θ, δ and x, and may also be one or more transition phase aluminum oxides selected from γ, η, θ, δ and x containing one or more added components selected from titanium, magnesium, boron, zirconium, thorium, niobium and rare earth, preferably γ-alumina and / or γ-alumina containing one or more added components selected from titanium, magnesium, boron, zirconium, thorium, niobium and rare earth. The aluminum oxide may be a commercially available product or may be prepared by any existing technology.

[0036] In one embodiment of the present invention, the BET specific surface area of ​​silicon oxide-alumina is 150 to 320 m2 / g, pore volume 0.2 ~ 1.3mL / g; the silica-alumina is a silica-alumina having a characteristic γ-alumina X-ray diffraction spectrum, based on the silica-alumina, the silica-alumina contains 5 to 60 weight % of silica and 40 to 95 weight % of alumina, preferably based on the silica-alumina, the silica-alumina contains 10 to 45 weight % of silica and 55 to 90 weight % of alumina.

[0037] The silicon oxide-aluminum oxide can be a commercially available product, or can be prepared by any existing technology.

[0038] In one embodiment of the present invention, the preparation of the carrier includes mixing, molding and calcining silica-alumina and / or its precursor with alumina and / or alumina precursor, wherein the amount of each component is such that the final carrier, the alumina precursor is selected from hydrated alumina, preferably pseudo-boehmite therein; the silica-alumina precursor is preferably silica-alumina with a pseudo-boehmite structure. They can be commercially available products, or they can be prepared by any existing technology. After calcination, the alumina precursor is an alumina with a pore volume of pores less than 60 angstroms accounting for more than 25% of the total pore volume, preferably more than 30%, and more preferably more than 35%. The calcination adopts the methods and conditions commonly used in the art, such as the calcination temperature can be 350-650°C; preferably 400-600°C, and the calcination time is 2-6 hours, preferably 3-5 hours.

[0039] In one embodiment of the present invention, the active metal component of the hydrocracking catalyst comprises platinum.

[0040] In one embodiment of the present invention, the reaction conditions of the hydrocracking unit are: reaction temperature 250-500°C, hydrogen partial pressure 1.0-10.0 MPa, liquid hourly volume space velocity 0.1-5.0 h -1 , hydrogen-oil volume ratio 300~1500;

[0041] The preferred reaction conditions of the hydrocracking unit are: reaction temperature 300-400°C, hydrogen partial pressure 3.0-8.0 MPa, liquid hourly volume space velocity 0.5-3.0 h -1 , hydrogen to oil volume ratio 500~1200.

[0042] In step (4) of the present invention, the reaction effluent of the hydrocracking unit enters the hydroisomerization unit and contacts with the hydroisomerization catalyst to carry out isomerization reaction, and the reaction effluent is subjected to gas-liquid separation and fractionation to obtain a naphtha fraction and a jet fuel component. The obtained jet fuel component meets the quality requirements of Appendix C "Kerosene component (HEFA-SPK) produced by the hydro-modification process of esters and fatty acids" of No. 3 jet fuel (GB 6537-2018). There is no diesel component in the reaction product of the hydroisomerization unit of the present invention, and the oil raw material is converted into the jet fuel component in the largest amount.

[0043] In a preferred case, the active metal component of the hydroisomerization catalyst contains palladium and platinum, and the mesoporous molecular sieve is selected from one or more of ZSM-22, Nu-10, Thete-1, ISI-1, ZSM-23, SAPO-11, SAPO-31, and SAPO-41.

[0044] In one embodiment of the present invention, the reaction conditions of the hydroisomerization unit are: reaction temperature 150-500°C, hydrogen partial pressure 1.0-10.0 MPa, liquid hourly volume space velocity 0.2-5.0 h -1 , the volume ratio of hydrogen to oil is 300 to 1000;

[0045] The preferred reaction conditions of the hydroisomerization unit are: reaction temperature 200-320°C, hydrogen partial pressure 0.3-8.0 MPa, liquid hourly volume space velocity 0.5-4.0 h -1 , the volume ratio of hydrogen to oil is 400-800.

[0046] Features of the present invention:

[0047] The method provided by the present invention is that the oil raw material is subjected to hydrogenation treatment to obtain normal alkanes, the normal alkanes are first subjected to hydrocracking and then to hydroisomerization, and the products of the hydroisomerization reaction are subjected to gas-liquid separation and fractionation to obtain jet fuel components. The present invention can obtain high-quality jet fuel components in maximum quantity by controlling the conversion rate of the fraction above 270°C of the hydrocracking unit, and has low energy consumption, effectively improving the economic benefits of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 It is a schematic diagram of one embodiment of the preparation of jet fuel components by hydrogenation of oil and fat raw materials provided by the present invention. DETAILED DESCRIPTION

[0049] The present invention will be further described below in conjunction with the accompanying drawings, but the present invention is not limited thereby.

[0050] Figure 1 FIG. 1 is a schematic diagram of one embodiment of the invention for preparing jet fuel components by hydrogenating oil and fat raw materials. Figure 1 As shown, the oil and fat raw material 1 and the circulating hydrogen 3 are mixed and then enter the hydroprocessing reactor 4 of the hydroprocessing unit. The hydroprocessing reactor is loaded with a hydroprocessing catalyst. The hydroprocessing reactor is a fixed bed reactor, containing one or more catalyst beds; if it contains multiple catalyst beds, cold hydrogen (circulating hydrogen 3) can be added between the catalyst beds to control the temperature rise of the catalyst beds. The reaction effluent 5 of the hydroprocessing reactor enters the high-pressure separator 6, and after gas-liquid separation, hydrogen-rich gaseous material 7, water 8 and liquid hydrocarbon 12 are obtained; the gaseous material 7 is purified by the hydrogen purification unit 9, and the purified hydrogen 10 is mixed with the new hydrogen 2 and then enters the compressor 11 for compression to obtain the circulating hydrogen 3.

[0051] The liquid hydrocarbon 12 enters the purification unit, and after stripping and vacuum drying, the dissolved impurities such as hydrogen sulfide, ammonia and water are removed, and then mixed with the circulating hydrogen 22 and enters the hydrocracking reactor 15 of the hydrocracking unit. The hydrocracking reactor is loaded with a hydrocracking catalyst. The hydrocracking reactor is a fixed bed reactor and may contain one or more catalyst beds. If it contains multiple catalyst beds, cold hydrogen (circulating hydrogen 21) may be added between the catalyst beds to control the temperature rise of the catalyst beds.

[0052] The reaction effluent 14 of the hydrocracking reactor enters the hydroisomerization reactor 15 of the hydroisomerization unit. The hydroisomerization reactor is loaded with a hydroisomerization catalyst. The hydroisomerization reactor is a fixed bed reactor containing one or more catalyst beds. The material 16 after the hydroisomerization reaction enters the high-pressure separator 17, and after gas-liquid separation, a hydrogen-rich gaseous material 18 and liquid hydrocarbons 19 are obtained. The gaseous material 18 and the new hydrogen 20 are mixed and then enter the compressor 21 to obtain circulating hydrogen 22. The liquid hydrocarbons 19 enter the fractionation tower 23, and after fractionation, liquefied gas 24, naphtha 25 and jet fuel components 26 are obtained.

[0053] The present invention will be further described below in conjunction with embodiments, but the present invention is not limited thereto.

[0054] Unless otherwise specified, all reagents used in the examples are pure chemical reagents.

[0055] The hydrogenation active components were determined by X-ray fluorescence spectroscopy.

[0056] The hydroprocessing catalyst used is RS-2000 catalyst, which is produced by Changling Catalyst Branch of Sinopec Catalyst Company.

[0057] The preparation method of the hydrocracking catalyst is as follows:

[0058] 68.5 g of CL-3 powder (a product of Changling Catalyst Plant, calcined at 550°C for 4 hours to obtain alumina D, whose specific surface area and pore distribution are listed in Table 1), CS powder (a product of Changling Refinery Catalyst Plant, containing 39.7% silicon oxide and 59.7% aluminum oxide, with a specific surface area of ​​332 m 2 / g, pore volume 1.11mL / g, XRD characterization shows pseudo-boehmite phase) 192.3g, ammonium fluoride 24.5g, extruded into a trilobal strip with an outer diameter of 1.5 mm, the wet strip was dried at 120°C for 4 hours, calcined at 600°C for 3 hours to obtain a carrier S, the composition of which is listed in Table 1. Take 100g of the carrier S, impregnate it with 96ml of ammonium chloroplatinate solution with a Pt content of 5.2g / L for 5 hours, then dry it at 105°C for 4 hours, and calcine it at 350°C for 2 hours to obtain a catalyst C. The content of metal platinum in the catalyst C is listed in Table 1. The catalyst was reduced in situ at 450°C for 4 hours before use.

[0059] The preparation method of the hydroisomerization catalyst is as follows:

[0060] A ZSM-22 molecular sieve (provided by Changling Catalyst Factory, with a silicon-aluminum ratio of 56) was mixed evenly with pseudo-boehmite P1-1 and sesbania powder, and a nitric acid aqueous solution was added and fully kneaded. Then, a clover-shaped strip with a diameter of 1.3 mm was extruded on an extruder, dried at 120°C for 4 hours, and then calcined at 600°C in air for 2 hours to obtain a carrier. The carrier was saturated with a solution containing Pt(NH3)4Cl2, then dried at 110°C for 4 hours, and calcined at 400°C in an air atmosphere for 3 hours to obtain a hydrogenation isomerization catalyst. The ZSM-22 content in the catalyst was 50.2% by weight, the alumina content was 49.0% by weight, and the Pt content was 0.8% by weight. The catalyst was reduced before use, with a reduction temperature of 350°C, a reduction time of 4 hours, and a hydrogen pressure of 0.1MPa.

[0061] Preparation of purified liquid hydrocarbons:

[0062] The hydroprocessing reactor was filled with 100 mL of RS-2000 catalyst. After the catalyst was sulfided, the reaction pressure was 6.0 MPa, the reaction temperature was 330 °C, and the volume space velocity was 2.0 h -1 Palm oil (properties shown in Table 2) and dimethyl disulfide containing 0.3 wt% were hydrogenated at a hydrogen-to-oil volume ratio of 1200. The resulting hydrotreated refined oil was purified to obtain purified liquid hydrocarbons, the properties of which are shown in Table 3.

[0063] Example 1

[0064] The hydrocracking reactor was filled with 100 mL of hydrocracking catalyst C. After the catalyst was reduced, the reaction pressure was 5.0 MPa and the volume space velocity was 1.0 h-1 Under the condition of hydrogen-to-oil volume ratio of 800, the hydrotreated refined oil is mixed with hydrogen for hydrocracking reaction, and the conversion rate of the fraction >270°C is controlled to be 60% by adjusting the reaction temperature.

[0065] The hydroisomerization reactor was filled with 100 mL of the prepared hydroisomerization catalyst. After the catalyst was reduced, the reaction pressure was 5.0 MPa, the reaction temperature was 290 °C, and the volume space velocity was 1.5 h -1 Under the conditions of , the reaction effluent from the hydrocracking reactor was subjected to a hydroisomerization reaction. The obtained reaction products were fractionated according to the cut point of 140°C, and the fractions above 140°C were jet fuel components. The reaction results are shown in Table 4.

[0066] Example 2

[0067] The hydrocracking reactor was filled with 100 mL of hydrocracking catalyst C. After the catalyst was reduced, the reaction pressure was 5.0 MPa and the volume space velocity was 1.0 h -1 Under the condition of hydrogen-to-oil volume ratio of 500, the hydrotreated refined oil is mixed with hydrogen and then subjected to hydrocracking reaction. The conversion rate of the fraction >270°C is controlled to be 80% by adjusting the reaction temperature.

[0068] The hydroisomerization reactor was filled with 100 mL of the prepared hydroisomerization catalyst. After the catalyst was reduced, the reaction pressure was 5.0 MPa, the reaction temperature was 280 °C, and the volume space velocity was 1.5 h -1 Under the conditions of , the reaction effluent from the hydrocracking reactor was subjected to a hydroisomerization reaction. The obtained reaction products were fractionated according to the cut point of 140°C, and the fractions above 140°C were jet fuel components. The reaction results are shown in Table 4.

[0069] Comparative Example 1

[0070] The hydrocracking reactor was filled with 100 mL of hydrocracking catalyst C. After the catalyst was reduced, the reaction pressure was 5.0 MPa and the volume space velocity was 1.0 h -1 The hydrotreated refined oil was mixed with hydrogen at a hydrogen-to-oil volume ratio of 500 and then subjected to a hydrocracking reaction. The conversion rate of the fraction >270°C was controlled to be 60% by adjusting the reaction temperature. The obtained reaction product was fractionated according to the cut point of 140°C, and the fraction above 140°C was the jet fuel component. The reaction results are shown in Table 4.

[0071] Comparative Example 2

[0072] The hydrocracking reactor was filled with 100 mL of hydrocracking catalyst. After the catalyst was reduced, the reaction pressure was 5.0 MPa and the volume space velocity was 1.0 h -1Under the condition of hydrogen-to-oil volume ratio of 500, the hydrotreated refined oil is mixed with hydrogen for hydrocracking reaction, and the conversion rate of the fraction >270°C is controlled to be 40% by adjusting the reaction temperature.

[0073] The hydroisomerization reactor was filled with 100 mL of the prepared hydroisomerization catalyst. After the catalyst was reduced, the reaction pressure was 5.0 MPa, the reaction temperature was 300 °C, and the volume space velocity was 1.5 h -1 Under the conditions of , the reaction effluent from the hydrocracking reactor was subjected to a hydroisomerization reaction. The obtained reaction products were fractionated according to the cut point of 140°C, and the fractions above 140°C were jet fuel components. The reaction results are shown in Table 4.

[0074] Comparative Example 3

[0075] The hydrocracking reactor was filled with 100 mL of hydrocracking catalyst C. After the catalyst was reduced, the reaction pressure was 5.0 MPa and the volume space velocity was 1.0 h -1 Under the condition of hydrogen-to-oil volume ratio of 500, the hydrotreated refined oil is mixed with hydrogen for hydrocracking reaction, and the conversion rate of the fraction >270°C is controlled to be 90% by adjusting the reaction temperature.

[0076] The hydroisomerization reactor was filled with 100 mL of the prepared hydroisomerization catalyst. After the catalyst was reduced, the reaction pressure was 5.0 MPa, the reaction temperature was 300 °C, and the volume space velocity was 1.5 h -1 Under the conditions of , the reaction effluent from the hydrocracking reactor was subjected to a hydroisomerization reaction. The obtained reaction products were fractionated according to the cut point of 140°C, and the fractions above 140°C were jet fuel components. The reaction results are shown in Table 4.

[0077] Table 1

[0078] project Alumina properties D <![CDATA[Specific surface area, m 2 / g]]> 221 Pore ​​volume, mL / g 0.41 Pore ​​distribution (angstroms), % 20-40 11.4 40-60 47.5 60-80 20.2 80-100 4.9 100-600 16.0 Carrier composition, weight % S Alumina 25 Silica-alumina 75 Catalyst metal composition, weight % C Pt, wt% 0.5

[0079] Table 2

[0080] project Palm Oil <![CDATA[Density (20 °C), kg / m 3 > 921.2 Total acid value, mgKOH / g 0.2 Oxygen content, % 11.4 Sulfur content, mg / kg ﹤2.0 Nitrogen content, mg / kg ﹤2.0

[0081] Table 3

[0082] project Numeric project Numeric <![CDATA[Density (20 °C) / (g / cm 3 )]]> 0.7773 Distillation range (D2887) / ℃ Freezing point / ℃ 17 IBP 254 Sulfur content / mg / kg <1.0 1％ 270 Nitrogen content / mg / kg 1.0 5％ 274 Normal alkanes mass fraction / % 99.35 10％ 276 Main normal alkanes mass fraction / % 30％ 294 <![CDATA[C 15 H 32 ]]> 15.69 50％ 309 <![CDATA[C 16 H 34 ]]> 22.70 70％ 322 <![CDATA[C 17 H 36 ]]> 24.85 90％ 328 <![CDATA[C 18 H 38 ]]> 34.00 95％ 329 total 97.24 FBP 334

[0083] Table 4

[0084]

Claims

1. A method for preparing jet fuel components by hydrogenating oil and fat raw materials, comprising: (1) Hydroprocessing unit: the oil and fat raw materials are contacted with the hydroprocessing catalyst in the presence of hydrogen to react. (2) Purification treatment unit: After the reaction effluent of the hydroprocessing unit is separated into gas and liquid, the resulting liquid phase stream is stripped and dried to obtain purified liquid hydrocarbons. (3) A hydrocracking unit, wherein the purified liquid hydrocarbon obtained from the purification treatment unit is contacted with a hydrocracking catalyst in the presence of hydrogen for reaction, wherein the hydrocracking catalyst comprises a carrier and an active metal component, wherein the carrier comprises alumina and silica-alumina, wherein the content of the alumina is 20-80% by weight, and the content of the silica-alumina is 80-20% by weight, based on the carrier; and the active metal component is one or more selected from Group VIII metals, wherein the content of the active metal component is 0.1-5% by weight, calculated as oxide, based on the total weight of the hydrocracking catalyst; and the conversion rate of the fraction having a temperature of >270°C in the hydrocracking unit is controlled to be 60%-80%. Conversion rate of fraction >270℃ = 100%*(mass fraction of fraction >270℃ in purified liquid hydrocarbons - mass fraction of fraction >270℃ in hydrocracking unit reaction products) / mass fraction of fraction >270℃ in purified liquid hydrocarbons; (4) a hydroisomerization unit, wherein the reaction effluent of the hydrocracking unit is contacted with a hydroisomerization catalyst for reaction, wherein the hydroisomerization catalyst comprises a carrier and an active metal component, wherein the carrier comprises a mesoporous molecular sieve and alumina, and the active metal component is selected from one or more of cobalt, nickel, palladium, platinum, molybdenum and tungsten. Based on the total weight of the hydroisomerization catalyst, the content of the mesoporous molecular sieve is 20-80% by weight, the content of alumina is 15-75% by weight, and the content of the active metal component is 0.2-5% by weight, calculated as oxide, and the sum of the contents of the above components is 100%; After the reaction effluent of the hydroisomerization unit is separated into gas and liquid, the resulting liquid phase stream is fractionated to obtain naphtha and jet fuel components.

2. The method according to claim 1, characterized in that Oil and fat raw materials include one or more of various animal and plant oils and catering waste oils.

3. The method according to claim 1, characterized in that: The hydroprocessing catalyst comprises a metal active component and a carrier, wherein the carrier is selected from one or more of aluminum oxide, silicon oxide, zirconium oxide, and titanium oxide, and the metal active component is at least one metal element selected from Group VIB and at least one metal element selected from Group VIII, wherein the Group VIB metal element is molybdenum and / or tungsten, and the Group VIII metal element is cobalt and / or nickel. Based on the total weight of the hydroprocessing catalyst, the content of the metal active component is 5 to 50% by weight in terms of oxide.

4. The method according to claim 3, characterized in that Based on the total weight of the hydroprocessing catalyst, the content of the VIB group metal element is 4-40% by weight, and the content of the VIII group metal element is 1-10% by weight, calculated as oxide; the metal active component contains cobalt and molybdenum.

5. The method according to claim 4, characterized in that Based on the total weight of the hydroprocessing catalyst, the content of the VIB group metal element is 8 to 35% by weight, and the content of the VIII group metal element is 2 to 5% by weight, calculated as oxide.

6. The method according to claim 1, characterized in that The reaction conditions of the hydroprocessing unit are: hydrogen partial pressure 1.0~15.0MPa, reaction temperature 150~450℃, liquid hourly volume space velocity 0.1~10h -1 , hydrogen-oil volume ratio 300~2000.

7. The method according to claim 1, characterized in that The reaction conditions of the hydroprocessing unit are: hydrogen partial pressure 3.0~10.0MPa, reaction temperature 250~400℃, liquid hourly volume space velocity 0.5~5.0h -1 , hydrogen-oil volume ratio 500~1500.

8. The method according to claim 1, characterized in that: In the purified liquid hydrocarbon obtained in step (2), the mass fraction of alkanes with carbon numbers of 15 to 18 is not less than 90%, the hydrogen sulfide content is not more than 5 mg / kg, and the water content is not more than 300 mg / kg.

9. The method according to claim 1, characterized in that: The carrier of the hydrocracking catalyst contains alumina and silica-alumina, and based on the carrier, the content of alumina is 25-75% by weight, and the content of silica-alumina is 75-25% by weight; The alumina is an alumina in which the pore volume of pores with pore diameters less than 60 angstroms accounts for more than 30% of the total pore volume; the active metal component of the hydrocracking catalyst includes platinum.

10. The method according to claim 1 or 9, characterized in that: The BET specific surface area of ​​silicon oxide-alumina is 150~320m 2 / g, pore volume 0.2~1.3mL / g; the silica-alumina is a silica-alumina having a characteristic γ-alumina X-ray diffraction spectrum, and based on the silica-alumina, the silica-alumina contains 5~60% by weight of silica and 40~95% by weight of alumina.

11. The method according to claim 10, characterized in that Based on the silica-alumina, the silica-alumina contains 10 to 45 wt % of silica and 55 to 90 wt % of alumina.

12. The method according to claim 1, characterized in that Reaction conditions of the hydrocracking unit: reaction temperature 250~500℃, hydrogen partial pressure 1.0~10.0MPa, liquid hourly volume space velocity 0.1~5.0h -1 , hydrogen to oil volume ratio 300~1500.

13. The method according to claim 1, characterized in that Reaction conditions of the hydrocracking unit: reaction temperature 300~400℃, hydrogen partial pressure 3.0~8.0MPa, liquid hourly volume space velocity 0.5~3.0h -1 , hydrogen-oil volume ratio 500~1200.

14. The method according to claim 1, characterized in that The active metal components of the hydroisomerization catalyst contain palladium and platinum, and the mesoporous molecules are selected from one or more of ZSM-22, Nu-10, Thete-1, ISI-1, ZSM-23, SAPO-11, SAPO-31, and SAPO-41.

15. The method according to claim 1, characterized in that The reaction conditions of the hydroisomerization unit are: reaction temperature 150~500℃, hydrogen partial pressure 1.0~10.0MPa, liquid hourly volume space velocity 0.2~5.0h -1 , the volume ratio of hydrogen to oil is 300~1000.

16. The method according to claim 1, characterized in that The reaction conditions of the hydroisomerization unit are: reaction temperature 200~320℃, hydrogen partial pressure 0.3~8.0MPa, liquid hourly volume space velocity 0.5~4.0h -1 , the volume ratio of hydrogen to oil is 400~800.

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