A hydrogenation method for producing jet fuel and industrial white oil from diesel

Abstract

The present invention relates to a hydrogenation method for producing jet fuel and industrial white oil from diesel oil, which includes: the diesel raw material oil enters a fixed-bed hydrogenation reactor and, in the presence of hydrogen and under the hydrogenation refining reaction conditions, successively contacts a hydrogenation refining catalyst and a hydrogenation refining catalyst II for reaction, and jet fuel and industrial white oil products are separated from the obtained reaction effluent. The present invention can produce high-density jet fuel and industrial white oil from low-quality diesel raw materials through a one-step hydrogenation reaction. The process flow of the present invention is simple, the conversion rate of the raw material oil is high, and the yield of the obtained high-density jet fuel is high.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrocarbon raw material processing, and particularly relates to a hydrogenation method for producing jet fuel and industrial white oil from diesel oil. Background Art

[0002] Since the 21st century, with the further development of aviation technology, higher requirements have been put forward for the flight range and payload of aircraft. Jet fuel, as the main fuel for jet aircraft, has strict indicators, such as good stability and low-temperature performance, and relatively good cleanliness. In addition, the demand for hypersonic flight technology and high endurance requires jet fuel to have a higher calorific value. When the fuel tank volume is fixed, jet fuel with a high calorific value and high density can effectively increase the energy carried by the fuel in the fuel tank, which is an important guarantee for the high-speed and long-range flight of aerospace vehicles. When the density of jet fuel increases from 780 kg / m 3 to 840 kg / m 3 , under the same fuel-carrying volume condition, the aircraft can carry about 10% more energy. Therefore, the development of high-density jet fuel has become one of the research hotspots. At the same time, due to the increasingly strict diesel standards in China, it is difficult to process inferior diesel oils with high aromatics and impurity content and low cetane number, such as catalytic diesel, into vehicle diesel fractions. Therefore, it is urgent to find a way out for this part of inferior diesel oil and rationally utilize it to produce high-value products.

[0003] CN106147854A discloses a method for producing high-specific-gravity aviation kerosene from coal tar. The method distills and cuts the coal tar raw material to obtain coal tar gasoline fractions and diesel fractions, and performs hydrogenation treatment on them to produce high-specific-gravity aviation fuel, while taking into account the production of naphtha fractions with high aromatic potential and clean diesel blending components.

[0004] CN105441127B discloses a method for producing jet fuel. When the raw material oil is obtained by distilling and cutting catalytic cracking diesel and / or coking diesel, the distillation and cutting make the boiling range of the raw material oil be 180 - 315 °C, preferably 180 - 300 °C, more preferably 180 - 290 °C. The light fraction is contacted with hydrogen and a hydrofining catalyst, and the yield of total naphthenes in the obtained jet fuel is 75 - 90% by weight.

[0005] CN105419865B discloses a method for producing jet fuel, comprising: contacting hydrogen and feedstock oil with a hydrofining catalyst for reaction; directly contacting the effluent of the hydrofining catalyst or separating out the gas-phase stream and then contacting it with a hydrocracking catalyst for reaction; separating jet fuel and diesel from the effluent of the hydrocracking catalyst; mixing at least part of the diesel with the feedstock oil or mixing at least part of the diesel with the liquid feed of the hydrocracking catalyst; the aromatic content of the feedstock oil being 40 wt% or more. This method can use catalytic cracking diesel as the feedstock to produce high-density jet fuel meeting the GJB16036 jet fuel standard with a high yield. Summary of the Invention

[0006] The object of the present invention is to provide a hydrogenation method for simultaneously producing high-density jet fuel and industrial white oil from inferior diesel.

[0007] The hydrogenation method for producing jet fuel and industrial white oil from diesel provided by the present invention comprises: the diesel feedstock oil enters a fixed-bed hydrogenation reactor and, in the presence of hydrogen, under hydrofining reaction conditions, contacts a hydrofining catalyst I for reaction; the obtained reaction effluent directly contacts a hydrofining catalyst II for reaction without separation; jet fuel and industrial white oil products are separated from the obtained reaction effluent; the content of naphthenes in the obtained jet fuel is 70-90 wt%; the content of naphthenes in the obtained industrial white oil is 50-70 wt%.

[0008] The hydrofining catalyst I comprises at least one Group VIII metal element, at least one Group VIB metal element and alumina; the pore volume of the hydrofining catalyst I is 0.2-0.4 cm 3 / g, the average pore diameter is 6-18 nm, and a bimodal pore size distribution is presented in the ranges of 2-6 nm and 8-20 nm in pore diameter.

[0009] The hydrofining catalyst II is a supported catalyst, and the carrier is selected from one or more of alumina, alumina-silica and titanium oxide; based on the whole hydrofining catalyst II, calculated as oxides, the content of nickel is 1-8 wt%, the content of cobalt element is 0-10 wt%, the content of molybdenum element is 0-20 wt%, and the content of tungsten element is 20-50 wt%.

[0010] In an embodiment of the present invention, the final boiling point of the diesel feedstock oil is not less than 340 °C, and the aromatic content is 70-95 wt%; the diesel feedstock oil is catalytic diesel or a mixture of catalytic diesel and coking diesel.

[0011] In one embodiment of the present invention, the conditions for the hydrofining reaction include: the temperature is 300 - 400 °C, the hydrogen partial pressure is 6 - 16 MPa, the liquid hourly space velocity is 0.1 - 3 h -1 , and the hydrogen - to - oil volume ratio is 100 - 1500 Nm 3 / m 3 .

[0012] When deeply hydrogenating and saturating catalytic cracking diesel, 70 - 90 wt% of the aromatics therein need to be saturated into naphthenes. Since the aromatics in the raw material include not only monocyclic aromatics but also bicyclic and tricyclic aromatics, reducing the aromatics content in the raw material to less than 10 wt% requires relatively harsh process conditions. And during the deep hydrogenation process, the content of nitrogen compounds in catalytic cracking diesel is relatively high, which will cause competitive adsorption on the hydrogenation active centers on the catalyst surface and affect the hydrogenation reaction of aromatics. Therefore, starting from the reaction mechanism of aromatics, the present invention uses hydrogenation catalysts with different reaction characteristics to give full play to the reaction advantages of each catalyst. The hydrofining catalyst I in the catalyst system has high denitrification activity to deeply remove the nitrogen compounds in the raw material; the hydrofining catalyst II has high aromatics saturation activity and stability to achieve deep saturation of aromatics.

[0013] In one embodiment of the present invention, based on the overall catalyst of the fixed - bed hydrogenation reactor, the filling ratio of the hydrofining catalyst I is 10 - 95 vol%, preferably 40 - 85 vol%.

[0014] In the present invention, the pore size of the hydrofining catalyst I shows a bimodal pore distribution in the ranges of 2 - 6 nm and 8 - 20 nm. The fact that the pore size of the hydrofining catalyst I shows a bimodal pore distribution in the ranges of 2 - 6 nm and 8 - 20 nm means that there are two peaks in the pore size distribution of the hydrofining catalyst I in the pore size ranges of 2 - 6 nm and 8 - 20 nm. Generally, the carrier also has a certain pore size distribution at 2 - 6 nm, but there is no peak in this part of the pores of the carrier, and no bimodal pores are formed.

[0015] Generally, the pore channels of the hydrofining catalyst are concentrated at 6 - 20 nm. There are reactant molecules of different sizes in the diesel raw material, and the larger reaction channels are relatively wide for the smaller reaction molecules. The pore size of 2 - 6 nm can provide a good reaction space for the smaller reactant molecules, improve the utilization efficiency of the internal pore channels of the catalyst, and achieve the purpose of improving the activity.

[0016] The pore channels of the preferred hydrofining catalyst I of the present invention exhibit a bimodal pore size distribution. A part of the pores are concentrated at the positions where the pore sizes of the carrier are concentratedly distributed, and the other part is concentrated at 2 - 6 nm. Due to the loading of the active metal components, pores at 2 - 6 nm are generated. Such a bimodal pore size structure can not only meet the requirement for the diffusion of reaction molecules to the active centers, but also load sufficient active metal components, resulting in a significant improvement in the performance of the hydrofining catalyst.

[0017] In the present invention, preferably, in the hydrofining catalyst I, the pore volume of the pores with a pore size distribution of 2 - 6 nm accounts for 8 - 15% of the total volume of the hydrofining catalyst I, and more preferably 9 - 12%. By adopting such a preferred embodiment, the effects of the active metal components in the smaller pores and the larger pores can be fully exerted, the reaction efficiency of the hydrofining catalyst I for sulfur - containing compounds and nitrogen - containing compounds of different sizes can be improved, and the purpose of making full use of the active metal can be achieved.

[0018] In one embodiment of the present invention, the specific surface area of the hydrofining catalyst I is 130 - 170 m 2 / g, the average pore size is 8 - 10 nm, and the pore volume is 0.25 - 0.4 cm 3 / g;

[0019] In the present invention, the determination of the specific surface area, pore volume, pore distribution, and average pore size of the hydrofining catalyst refers to the determination after the catalyst is calcined at 400 °C for 3 h.

[0020] In the present invention, the specific surface area, pore distribution, average pore size, and pore volume of the catalyst are measured by the low - temperature nitrogen adsorption method (BET) (see "Petrochemical Analysis Methods (RIPP Test Methods)", edited by Yang Cuiding et al., published by Science Press in 1990). Among them, the pore volume of 2 - 100 nm is calculated according to the BET results.

[0021] In the present invention, unless otherwise specified, the pores of 2 - 6 nm refer to the pores with a pore size greater than or equal to 2 nm and less than 6 nm, the pores of 2 - 4 nm refer to the pores with a pore size greater than or equal to 2 nm and less than 4 nm, the pores of 4 - 6 nm refer to the pores with a pore size greater than or equal to 4 nm and less than 6 nm, and the pores of 8 - 20 nm refer to the pores with a pore size greater than or equal to 8 nm and less than 20 nm.

[0022] In one embodiment of the present invention, the composition of the hydrofining catalyst I is (Xi ai )·(Yi bi )·(Zi ci)·When "Sup" is indicated, where Xi is a Group VIB metal oxide, ai is the mass relative to 1 g of the carrier Xi, Yi is a Group VIII metal oxide, bi is the mass relative to 1 g of the carrier Yi, Zi is P2O5, ci is the mass relative to 1 g of the carrier P2O5, and Sup refers to the carrier in the catalyst, the mass of which is counted as 1 g, (ai / ρ Xi +ai / ρ Yi +ci / ρ Zi ) / SA sup has a value in the range of 0.4 - 0.9 nm, preferably 0.5 - 0.8, ρ Xi 、ρ Yi 、ρ Zi are the densities of the Group VIB metal oxide, the Group VIII metal oxide, and P2O5 respectively, and SA sup is the specific surface area of the carrier. The advantage of adopting this preferred embodiment is that it can ensure the formation of a better bimodal pore structure inside the catalyst, with some pores concentrated in the range of 2 - 6 nm.

[0023] In the present invention, ρMoO3, ρWO3, ρNiO, ρCoO, and ρP2O5 are calculated as 4.69 g / cm 3 、7.16 g / cm 3 、6.67 g / cm 3 、6.45 g / cm 3 and 2.39 g / cm 3 respectively.

[0024] In the present invention, the Group VIII metal elements include but are not limited to at least one of Fe, Co, Ni, Ru, Pt, and Pd, preferably Co and / or Ni.

[0025] In a preferred case, the Group VIB metal elements include but are not limited to at least one of Cr, Mo, and W, preferably Mo and / or W.

[0026] In the present invention, there is no specific limitation on the amounts of P2O5 and the Group VIB metal oxide in the hydrofining catalyst I, as long as the performance of the hydrofining catalyst I can be improved. Preferably, the molar ratio of Zi / Xi in the hydrofining catalyst I is 0.05 - 0.3, and more preferably 0.08 - 0.2.

[0027] In a preferred case, in order to further improve the performance of the hydrofining catalyst I, the atomic concentration of the Group VIB metal element on the surface of the carrier in the hydrofining catalyst I is 5 - 13 atom / nm 2 , preferably 5 - 11 atom / nm 2The advantage of adopting this preferred embodiment is that the amount of active metal is relatively moderate, which can promote the formation of pores with a diameter of 2-6 nm.

[0028] In the present invention, the atomic concentration of the Group VIB metal element on the carrier surface refers to the average atomic concentration of the Group VIB metal element on the carrier surface, which is obtained by measuring the metal loading amount and the specific surface area of the carrier and then through calculation. Specifically, it can be obtained through the following calculation: Atomic concentration = (ai / M Xi ) × N A / (1 × SA sup ), where N A is Avogadro's constant, ai is the mass of Xi relative to 1 gram of the carrier, M Xi is the molecular weight of Xi, and SA sup is the specific surface area of the carrier.

[0029] In an embodiment of the present invention, the atomic ratio of the Group VIII metal element to the total amount of the Group VIII metal element and the Group VIB metal element in the hydrofining catalyst I is 0.05-0.35, preferably 0.1-0.3.

[0030] In an embodiment of the present invention, the hydrofining catalyst I further contains one or more -OH-containing organic alcohol compounds and / or carboxylic acid compounds. The molar ratio of the organic alcohol compound and / or carboxylic acid compound to the Group VIII metal element is 1-6, preferably 2-5. The purpose of adopting this preferred embodiment is to ensure that the Group VIII metal element has a high dispersion ability, weaken the interaction between the carrier and the metal, and promote the formation of more active phases.

[0031] The -OH-containing organic alcohol compound can be at least one of a monohydric alcohol, a dihydric alcohol, and a polyhydric alcohol. In a preferred case, the -OH-containing organic alcohol compound is selected from one or more of methanol, ethanol, propanol, isopropanol, butanol, isobutanol, pentanol, heptanol, ethylene glycol, glycerol, butanetetraol, polyethylene glycol, polyglycerol, pentaerythritol, xylitol, sorbitol, and trimethylolethane, preferably at least one of glycerol, propanol, and ethylene glycol.

[0032] In a preferred case, the carboxylic acid compound is selected from one or more of formic acid, acetic acid, propionic acid, citric acid, octanoic acid, adipic acid, malonic acid, succinic acid, maleic acid, valeric acid, hexanoic acid, capric acid, benzoic acid, phenylacetic acid, phthalic acid, terephthalic acid, valeric acid, hexanoic acid, capric acid, stearic acid, and tartaric acid, preferably at least one of formic acid, citric acid, and acetic acid.

[0033] In a particularly preferred case, the catalyst further contains one or more of methanol, ethanol, propanol, isopropanol, butanol, isobutanol, pentanol, heptanol, ethylene glycol, glycerol, pentaerythritol, xylitol, sorbitol, trimethylolethane and / or formic acid, acetic acid, propionic acid, citric acid, octanoic acid, adipic acid, malonic acid, succinic acid, maleic acid, valeric acid, hexanoic acid, capric acid, benzoic acid, phenylacetic acid, phthalic acid, terephthalic acid, valeric acid, hexanoic acid, capric acid, stearic acid, tartaric acid.

[0034] In one embodiment of the present invention, the equivalent diameter of the hydrofining catalyst I is 0.5 - 1.8 mm, more preferably 0.8 - 1.6 mm. There is no specific limitation on the shape of the hydrofining catalyst I, and the conventional catalyst shapes in the art are applicable to the present invention. Preferably, the shape of the catalyst is cylindrical, clover-shaped, four-leaf clover-shaped, butterfly-shaped, honeycomb-shaped or other irregular shapes, and more preferably butterfly-shaped.

[0035] In one embodiment of the present invention, the hydrofining catalyst I is prepared by impregnating alumina with a Group VIII metal precursor, a Group VIB metal precursor, a phosphorus-containing compound, and optionally an -OH-containing organic alcohol compound and / or a carboxylic acid compound, and then drying.

[0036] The impregnation method includes: impregnating the alumina with an impregnating solution containing a Group VIII metal precursor, a Group VIB metal precursor, a phosphorus-containing compound, and optionally an -OH-containing organic alcohol compound and / or a carboxylic acid compound;

[0037] Preferably, the -OH-containing organic alcohol compound and / or carboxylic acid compound, the Group VIII metal precursor, and the Group VIB metal precursor are added to an aqueous solution of the phosphorus-containing compound to provide the impregnating solution;

[0038] Preferably, the drying conditions include: a temperature of 80 - 200 °C and a time of 1 - 10 h.

[0039] In the present invention, the types of metal elements in the Group VIB metal oxide and the Group VIII metal oxide are provided by the precursors containing the above metal elements. Preferably, the Group VIB metal precursor is selected from at least one of ammonium heptamolybdate, ammonium molybdate, ammonium phosphomolybdate, molybdenum oxide, ammonium metatungstate, ethylammonium metatungstate, and tungsten oxide.

[0040] In a preferred case, the Group VIII metal precursor is selected from at least one of cobalt nitrate, basic cobalt carbonate, cobalt acetate, cobalt oxide, nickel nitrate, basic nickel carbonate, nickel acetate, and nickel oxide.

[0041] In a particularly preferred embodiment, the Group VIB metal and Group VIII metal precursors are selected from at least one of ammonium heptamolybdate, ammonium molybdate, ammonium phosphomolybdate, molybdenum oxide, ammonium metatungstate, ethylammonium metatungstate, tungsten oxide, cobalt nitrate, cobalt basic carbonate, cobalt acetate, cobalt oxide, nickel nitrate, nickel basic carbonate, nickel acetate, and nickel oxide.

[0042] In the present invention, P2O5 is provided by a phosphorus-containing compound. Preferably, the phosphorus-containing compound is selected from at least one of phosphoric acid, hypophosphorous acid, ammonium phosphate, and ammonium dihydrogen phosphate.

[0043] Preferably, the water absorption rate of the alumina is greater than 0.9 mL / g, preferably 0.9 - 1.2 mL / g.

[0044] Preferably, the specific surface area of the alumina is greater than 260 m 2 / g, preferably 260 - 400 m 2 / g.

[0045] Preferably, the average pore diameter of the alumina is greater than 8 nm, more preferably 8 - 14 nm, and the pore size distribution pattern is a single-peak pore distribution. The advantage of adopting this preferred embodiment is that it can ensure sufficient pore space. On the one hand, a certain number of pores with a diameter of 2 - 6 nm can be formed, and on the other hand, the effects of all active metal components can be exerted.

[0046] In a preferred case, in the alumina, the pore volume of pores with a pore diameter distribution of 2 - 6 nm accounts for no more than 10% of the total pore volume of the alumina, more preferably no more than 8%, and further preferably 5 - 8%.

[0047] In a particularly preferred case, in the alumina, the pore volume of pores with a pore diameter distribution of 2 - 4 nm accounts for no more than 4% of the total volume of the alumina, more preferably no more than 2%.

[0048] In the present invention, the hydrofining catalyst II is a supported catalyst, and the carrier is selected from one or more of alumina, alumina-silica, and titanium oxide. Based on the whole hydrofining catalyst II, calculated as oxides, the content of nickel is 1 - 8 wt%, the content of cobalt element is 0 - 10 wt%, the content of molybdenum element is 0 - 20 wt%, and the content of tungsten element is 20 - 50 wt%.

[0049] The present invention places no particular limitation on the preparation method of the hydrofining catalyst II, and any method capable of preparing the hydrofining catalyst II can be used in the present invention.

[0050] In one embodiment of the present invention, the reaction effluent is first subjected to gas-liquid separation in a high-pressure separator to separate the gas-phase stream therein. The gas-phase stream separated in the high-pressure separator is a hydrogen-rich gas, and this hydrogen-rich gas can be used as recycle hydrogen after purification and pressurization. The liquid-phase stream obtained from the separation in the high-pressure separator enters a low-pressure separator for further gas-liquid separation, and the obtained liquid-phase stream enters a fractionating tower for fractionation to obtain jet fuel and industrial white oil. The hydrofining reaction conditions result in a jet fuel yield of 50 - 80 wt% and an industrial white oil yield of 25 - 50 wt%.

[0051] In one embodiment of the present invention, the distillation range of the jet fuel is 170 - 270 °C. The initial boiling point of the industrial white oil fraction is 270 °C. In the present invention, the distillation range of the jet fuel and industrial white oil is measured by the method specified in ASTM D - 86.

[0052] The jet fuel obtained by the present invention is a high-density jet fuel, and its density is in the range of 0.835 - 0.860 g / cm 3 The jet fuel produced by the method of the present invention has a high net calorific value, which can reach more than 42.9 MJ / kg. The density of the industrial white oil component produced by the method of the present invention can reach in the range of 0.835 - 0.860 g / cm 3 and at the same time, the kinematic viscosity can reach 4.2 mm 2 / s, meeting the SH / T 0006 - 2017 standard for industrial white oil (I).

[0053] According to the method of the present invention, the hydrofining catalyst I has a high denitrification activity, which promotes the hydrofining catalyst II to exert its high aromatics activity. Under mild process conditions, the aromatics in the raw material can be hydrogenated and saturated to form naphthenes. According to the method of the present invention, the hydrofining reaction conditions result in a naphthene yield of 60 - 92% in the obtained jet fuel.

[0054] Preferably, the total aromatics saturation rate in the obtained hydrogenation product is 70 - 98 wt%, preferably 80 - 98 wt%.

[0055] The total aromatics saturation rate is calculated by the following formula:

[0056] Total aromatics saturation rate = [(mass of aromatics in the feedstock - mass of aromatics in the obtained hydrogenation product) / mass of aromatics in the feedstock] × 100%.

[0057] The calculation formula for the naphthene yield in the product is as follows:

[0058] Naphthene yield = yield of the product in the hydrogenation liquid product * naphthene content in the product

[0059] Features of the present invention:

[0060] (1) By using the method of the present invention, inferior diesel oils such as catalytic diesel can be utilized to produce high-density jet fuels meeting the GJB1603 No. 6 jet fuel standard, with a density reaching 0.835 g / cm 3 or above, a weight calorific value reaching or exceeding 42.9 MJ / kg, and a yield that can reach 50 - 70%; meanwhile, industrial white oil meeting the standard requirements can be produced.

[0061] (2) According to the method of the present invention, through the reasonable matching of two catalysts in the hydrogenation reaction zone, the obtained catalyst system has excellent aromatic saturation activity. Therefore, high-density jet fuel and industrial white oil can be obtained through a one-step hydrogenation reaction. The process flow of the present invention is simple, and the feedstock oil can achieve nearly 100% conversion, while the yield of high-density jet fuel is relatively high. The method of the present invention can be used for new and existing devices and has good feasibility. Description of the Drawings

[0062] Figure 1 is a process flow schematic diagram of the hydrogenation method for producing jet fuel and industrial white oil from diesel provided by the present invention. Detailed Embodiments

[0063] The present invention will be further described below in conjunction with the drawings, but the present invention is not limited thereby.

[0064] Figure 1 is a process flow schematic diagram of the hydrogenation method for producing jet fuel and industrial white oil from diesel provided by the present invention. As Figure 1 shown, the diesel feedstock oil 2 is mixed with hydrogen and then enters the heating furnace 3 for heating, and then enters the fixed-bed hydrogenation reactor 4 to contact and react with the hydrofining catalyst I (4-1) and the hydrofining catalyst II (4-2) in sequence. The reaction effluent from the hydrogenation reactor enters the high-pressure separator 6 for gas-liquid separation, obtaining a gas-phase stream 16 and a liquid-phase stream 17. The gas-phase stream 16 is a hydrogen-rich gas. After entering the recycle hydrogen purification unit 7 to remove impurities therein (such as sulfur-containing compounds and / or nitrogen-containing compounds), it is compressed and pressurized by the recycle hydrogen compression unit 8. Part of it is used as recycle hydrogen, and the other part is used as cold hydrogen 5 to enter the catalyst bed layer of the fixed-bed hydrogenation reactor. The make-up hydrogen 1 is mixed with the recycle hydrogen output from the recycle hydrogen compression unit 8. The liquid-phase stream 17 enters the low-pressure separator 9 for further gas-liquid separation, obtaining a gas stream 10 and a liquid stream 15, and the gas stream 10 is discharged from the device. The liquid stream 15 enters the fractionating tower 11 for fractionation, obtaining jet fuel 13, industrial white oil 14, and possibly a small amount of light naphtha 12.

[0065] The present invention will be further described below in conjunction with embodiments, but the present invention is not limited thereby.

[0066] Examples 1-3 are used to illustrate the method of the present invention.

[0067] In the following examples and comparative examples, ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis) was performed using a Lambda 35 type multi-functional ultraviolet-visible spectrophotometer from Perkin-Elmer, USA. The ultraviolet absorption spectrum of the solution in the range of 450-900 nm was measured under the experimental conditions of a neon lamp light source, a measurement wavelength of 286 nm, a slit width of 1.0 nm, a sample detection time of 4.5 min, and a detection step size of 2.0 s.

[0068] In the following examples and comparative examples, the content of each element in the catalyst was analyzed using a 3271E type X-ray fluorescence spectrometer commercially purchased from Rigaku Denki Kogyo Co., Ltd., Japan.

[0069] In the following examples and comparative examples, the jet fuel fraction yield is defined as the weight percentage of the jet fuel fraction fractionated from the whole fraction product through the fractionation tower to the feedstock oil.

[0070] The specific raw material property data of the diesel feedstock used are shown in Table 1, where Feedstock A is a mixture of catalytic diesel and coking diesel, and the mass ratio is 9:1; Feedstock B is catalytic diesel, and the above feedstocks are all industrial feedstocks.

[0071] Example 1

[0072] The hydrofining catalyst I used in this example was prepared by the following method.

[0073] A γ-alumina support was selected, with a water absorption rate of 0.98 mL / g, a specific surface area of 280 m 2 / g, an average pore diameter of 10.7 nm, the pore volume with a pore diameter of 2-6 nm accounting for 8% of the total pore volume, the pore volume with a pore diameter of 2-4 nm accounting for 4% of the total pore volume, and the pore size distribution mainly concentrated in 8-20 nm.

[0074] Ammonium metatungstate, basic nickel carbonate, and citric acid were respectively added to the phosphoric acid aqueous solution, heated and stirred at 90 °C for 2 h until completely dissolved and kept at a constant temperature for 3 h to obtain an impregnation solution containing active metal components. After mixing the impregnation solution with the support evenly and standing for 2 h, it was dried at 130 °C for 3 h to prepare a catalyst with a particle size of 1.6 mm and a butterfly shape.

[0075] The dosages of the support and each component were such that the prepared catalyst satisfied:

[0076] The atomic concentration of W in the catalyst was 5 atom / nm 2, the Ni / (Ni + W) atomic ratio is 0.3, the P2O5 / WO3 molar ratio is 0.2, (ai / ρ Xi +bi / ρ Yi +ci / ρ Zi ) / SA sup is 0.407 nm, and the molar ratio of citric acid to Ni is 2.

[0077] After the catalyst was calcined at 400 °C for 3 h, its pore size distribution was analyzed by low-temperature nitrogen adsorption. The specific surface area of the catalyst is 162 m 2 / g, the pore volume is 0.39 cm 3 / g, the average pore size is 9.6 nm, and the pore structure shows a bimodal pore distribution characteristic at 2 - 6 nm and 8 - 20 nm. The proportion of the pore volume with a pore size of 2 - 6 nm in the total pore volume is 10.5%. The prepared catalyst is numbered C1.

[0078] The hydrofining catalyst II used in this example is the industrial catalyst RN-32L developed by the Research Institute of Petroleum Processing, Sinopec. Its specific active metal composition is: the content of MO3 is 2.4%, the content of NiO is 2.3%, and the content of WO3 is 23.0%.

[0079] Hydrogenation reaction was carried out using raw material A, and the specific process conditions and product distribution are shown in Table 2.

[0080] Table 1

[0081]

[0082] Example 2

[0083] The hydrofining catalyst I used in this example was prepared by the following method.

[0084] A γ-alumina support was selected, with a water absorption rate of 0.98 mL / g, a specific surface area of 280 m 2 / g, an average pore size of 10.7 nm, the proportion of the pore volume with a pore size of 2 - 6 nm in the total pore volume is 8%, the proportion of the pore volume with a pore size of 2 - 4 nm in the total pore volume is 4%, and the pore size distribution is mainly concentrated at 8 - 20 nm.

[0085] Ammonium metatungstate, basic nickel carbonate, and citric acid were respectively added to the phosphoric acid aqueous solution, and heated and stirred at 90 °C for 2 h until completely dissolved and kept at a constant temperature for 3 h to obtain an impregnation solution containing active metal components. After mixing the impregnation solution with the support evenly and standing for 2 h, it was dried at 130 °C for 3 h to prepare a catalyst with a particle size of 1.6 mm and a butterfly shape.

[0086] The amounts of the support and each component were such that the prepared catalyst satisfied:

[0087] The atomic concentration of W in the catalyst is 8 atom / nm 2 , the atomic ratio of Ni / (Ni + W) is 0.28, the molar ratio of P2O5 / WO3 is 0.2, (ai / ρ Xi +bi / ρ Yi +ci / ρ Zi ) / SA sup is 0.623 nm, and the molar ratio of citric acid to Ni is 2.

[0088] After the catalyst is calcined at 400 °C for 3 h, its pore size distribution is analyzed by low-temperature nitrogen adsorption. The specific surface area of the catalyst is 165 m 2 / g, the pore volume is 0.40 cm 3 / g, the average pore size is 8.6 nm, the pore structure shows a bimodal pore distribution characteristic at 2 - 6 nm and 8 - 20 nm, and the proportion of the pore volume with a pore size of 2 - 6 nm in the total pore volume is 10.8%. The prepared catalyst is numbered C2.

[0089] The hydrofining catalyst II used in this example is the industrial catalyst RN-32L developed by the Research Institute of Petroleum Processing, SINOPEC. The hydrogenation reaction is carried out with raw material B, and the specific process conditions and product distribution are shown in Table 2.

[0090] Example 3

[0091] The hydrofining catalyst I used in this example is prepared by the following method.

[0092] Select a γ-alumina support with a water absorption rate of 0.98 mL / g, a specific surface area of 280 m 2 / g, an average pore size of 10.7 nm, the proportion of the pore volume with a pore size of 2 - 6 nm in the total pore volume is 8%, the proportion of the pore volume with a pore size of 2 - 4 nm in the total pore volume is 4%, and the pore size distribution is mainly concentrated at 8 - 20 nm.

[0093] Ammonium metatungstate, basic nickel carbonate, and citric acid are respectively added to the phosphoric acid aqueous solution, heated and stirred at 90 °C for 2 h until completely dissolved and kept at a constant temperature for 3 h to obtain an impregnation solution containing active metal components. After the impregnation solution is mixed evenly with the support and left standing for 2 h, it is dried at 130 °C for 3 h to prepare a catalyst with a particle size of 1.6 mm and a butterfly shape.

[0094] The dosages of the support and each component are such that the prepared catalyst satisfies:[[]]

[0095] The atomic concentration of W in the catalyst is 9 atom / nm 2 , the atomic ratio of Ni / (Ni + W) is 0.25, the molar ratio of P2O5 / WO3 is 0.2, (ai / ρ Xi +bi / ρ Yi+ci / ρ Zi ) / SA sup is 0.62 nm, and the molar ratio of citric acid to Ni is 2.

[0096] After the catalyst was calcined at 400 °C for 3 h, its pore size distribution was analyzed by low-temperature nitrogen adsorption. The specific surface area of the catalyst was 164 m 2 / g, the pore volume was 0.38 cm 3 / g, the average pore size was 8.4 nm, and the pore structure showed a bimodal pore distribution characteristic at 2 - 6 nm and 8 - 20 nm. The proportion of the pore volume with a pore size of 2 - 6 nm in the total pore volume was 9.8%. The prepared catalyst was numbered C3.

[0097] The hydrofining catalyst II used in this example was the industrial catalyst RN-32L developed by the Research Institute of Petroleum Processing, SINOPEC. The hydrogenation reaction was carried out with raw material B, and the specific process conditions and product distribution are shown in Table 2.

[0098] Comparative Example 1

[0099] The hydrofining catalyst II used in this example was the same as that in Example 1. The hydrofining catalyst I was prepared by the following method.

[0100] The same carrier as that in Example 1 was selected to prepare the catalyst. A certain amount of MoO3, basic nickel carbonate, and glycerol were respectively added to the aqueous solution containing phosphoric acid, and they were completely dissolved under heating and stirring to obtain an impregnation solution containing active metals. After the impregnation solution was mixed evenly with the carrier, it was dried at 120 °C for 5 h to prepare an oxidized catalyst with a particle size of 1.6 mm.

[0101] The surface concentration of Mo in the catalyst was 4 atom / nm 2 , the atomic ratio of Ni / (Ni + Mo) was 0.22, the molar ratio of P2O5 / MoO3 was 0.3, (ai / ρ Xi +ai / ρ Yi +ci / ρ Zi ) / SA sup was 0.34 nm, and the atomic ratio of glycerol to Ni was 2.

[0102] After the catalyst was calcined at 400 °C for 3 h, its pore size distribution was analyzed by low-temperature nitrogen adsorption and mercury intrusion porosimetry. The specific surface area of the catalyst was 205 m 2 / g, the pore volume was 0.48 cm 3 / g, and the pore size distribution of the catalyst was a single-peak pore. The prepared catalyst was numbered D1. The hydrogenation reaction was carried out with raw material B, and the specific process conditions and product distribution are shown in Table 3.

[0103] Comparative Example 2

[0104] In this example, both the hydrofining catalyst I and the hydrofining catalyst II used are the industrial catalyst RN-32L developed by the Research Institute of Petroleum Processing, SINOPEC. The hydrogenation reaction is carried out using raw material B, and the specific process conditions and product distribution are shown in Table 3.

[0105] Comparative Example 3

[0106] The catalysts used in this comparative example are the same as those in Example 1, but the order scheme of catalyst grading is opposite to that in Example 1. The hydrogenation reaction is carried out using raw material A, and the specific process conditions and product distribution are shown in Table 3.

[0107] The results of Examples 1 - 3 confirm that by using the hydrofining catalyst I prepared by the method of the present invention and through the synergistic effect between the hydrofining catalyst I and the hydrofining catalyst II, ultra-deep hydrogenation saturation of aromatics is achieved. Using raw material A or raw material B, the prepared jet fuel meets the technical requirements of GJB1603-93 No. 6 jet fuel, and the produced white oil product meets the requirements of the industrial white oil (I) standard. However, due to the relatively low hydrogenation activity of catalyst D1 in Comparative Example 1 and the lack of reasonable catalyst grading in Comparative Examples 2 and 3, the smoke point of the obtained jet fuel is lower than 20 mm and cannot meet the technical requirements of GJB1603-93 No. 6 jet fuel. At the same time, the sulfur content of the white oil fraction exceeds 10 μg / g and cannot be used as a white oil fraction.

[0108] Table 2

[0109]

[0110]

[0111] Table 3

[0112]

[0113]

[0114]

Claims

1. A hydrogenation method for producing jet fuel and industrial white oil from diesel, comprising: Diesel raw material oil enters a fixed-bed hydrotreating reactor and reacts with hydrotreating catalyst I under hydrotreating reaction conditions in the presence of hydrogen. The resulting reaction effluent directly contacts hydrotreating catalyst II for reaction without separation. Jet fuel and industrial white oil products are separated from the resulting reaction effluent. The content of naphthenes in the obtained jet fuel is 70 - 90 wt%, and the content of naphthenes in the obtained industrial white oil is 50 - 70 wt%. The hydrofining catalyst I contains at least one Group VIII metal element, at least one Group VIB metal element, and alumina. The pore volume of the hydrofining catalyst I is 0.2 - 0.4 cm 3 / g, and the average pore diameter is 6 - 18 nm, where a bimodal pore size distribution is presented in the ranges of 2 - 6 nm and 8 - 20 nm. The specific surface area of the hydrofining catalyst I is 130 - 170 m 2 / g, and the pore volume with a pore diameter distribution in the range of 2 - 6 nm accounts for 8 - 15% of the total pore volume of the catalyst; The hydrotreating catalyst II is a supported catalyst, and the carrier is selected from one or more of alumina, alumina-silica, and titanium oxide. Based on the total hydrotreating catalyst II, calculated as oxides, the content of nickel is 1 - 8 wt%, the content of cobalt element is 0 - 10 wt%, the content of molybdenum element is 0 - 20 wt%, and the content of tungsten element is 20 - 50 wt%.

2. The method according to claim 1, wherein The final boiling point of the diesel raw material oil is not less than 340 °C, and the content of aromatics is 70 - 95 wt%. The diesel raw material oil is catalytic diesel or a mixture of catalytic diesel and coker diesel.

3. The method according to claim 1, characterized in that The hydrofining reaction conditions include: temperature of 300 - 400 °C, hydrogen partial pressure of 6 - 16 MPa, liquid hourly space velocity of 0.1 - 3 h -1 , hydrogen-oil volume ratio of 100 - 1500 Nm 3 / m 3 .

4. The method according to claim 1, wherein Based on the total catalyst in the fixed-bed hydrotreating reactor, the filling ratio of hydrotreating catalyst I is 10 - 95 vol%.

5. The method according to claim 1, characterized in that Based on the total catalyst in the fixed-bed hydrotreating reactor, the filling ratio of hydrotreating catalyst I is 40 - 85 vol%.

6. The method according to claim 1, wherein The average pore diameter of the hydrofining catalyst I is 8-10 nm, and the pore volume is 0.25-0.4 cm 3 / g; The pore volume of pores with a pore size distribution of 2 - 6 nm accounts for 9 - 12% of the total pore volume of the catalyst.

7. The method according to claim 1, characterized in that, The composition of the hydrofining catalyst I is expressed as (Xi ai )•(Yi bi )•(Zi ci ), where Xi is a metal oxide of Group VIB, ai is the mass relative to 1 g of the support Xi, Yi is a metal oxide of Group VIII, bi is the mass relative to 1 g of the support Yi, Zi is P2O5, ci is the mass relative to 1 g of the support P2O5, Sup refers to the support in the catalyst, and its mass is calculated as 1 g. The value of (ai / ρ Xi + ai / ρ Yi + ci / ρ Zi ) / SA sup is in the range of 0.4 - 0.9 nm. ρ Xi , ρ Yi , and ρ Zi are the densities of the metal oxide of Group VIB, the metal oxide of Group VIII, and P2O5 respectively, and SA sup is the specific surface area of the support.

8. The method according to claim 7, characterized in that (ai / ρ Xi +ai / ρ Yi +ci / ρ Zi ) / SA sup The value is 0.5 - 0.8 nm.

9. The method according to claim 7, characterized in that The molar ratio of Zi / Xi in hydrotreating catalyst I is 0.05 - 0.

3.

10. The method according to claim 7, wherein The molar ratio of Zi / Xi in hydrotreating catalyst I is 0.08 - 0.

2.

11. The method according to claim 1, wherein The atomic ratio of Group VIII metal elements in hydrotreating catalyst I to the total amount of Group VIII metal elements and Group VIB metal elements is 0.05 - 0.

35.

12. The method according to claim 1, characterized in that The atomic ratio of Group VIII metal elements in hydrotreating catalyst I to the total amount of Group VIII metal elements and Group VIB metal elements is 0.1 - 0.

3.

13. The method according to claim 1, wherein Hydrotreating catalyst I also contains one or more organic alcohol compounds and / or carboxylic acid compounds, and the molar ratio of the organic alcohol compounds and / or carboxylic acid compounds to the Group VIII metal elements is 1 - 6.

14. The method according to claim 13, characterized in that The molar ratio of the organic alcohol compounds and / or carboxylic acid compounds to the Group VIII metal elements is 2 - 5.

15. The method according to claim 1, wherein The hydrotreating reaction conditions result in a jet fuel yield of 50 - 80 wt% and an industrial white oil yield of 25 - 50 wt%.

Images