CN102010751B - Efficient combined production method for gasoline with ultralow sulfur and high octane value - Google Patents

Abstract

The invention relates to a high-efficiency combined production method of ultra-low sulfur and high-octane gasoline. The production method comprises: subjecting low-quality full-distillate gasoline raw materials to low-temperature directional sulfur transfer reaction under hydrogen-facing conditions, and then performing oil product cutting and fractionation to obtain light-distillate gasoline and heavy-distillate gasoline. The cut-off fractionation temperature is 50-90°C; Distillate gasoline is contacted with selective hydrodesulfurization catalyst and supplemental desulfurization-hydrocarbon isomerization/aromatization catalyst; blending light-distillate gasoline and treated heavy-distillate gasoline to obtain ultra-low sulfur and high octane gasoline products. The invention is applicable to the upgrading of inferior gasoline, especially for inferior catalytic cracking gasoline with ultra-high sulfur and high olefins, which can obtain very good effects of ultra-deep desulfurization and olefin reduction, and can maintain or increase the octane number of the product after the reaction and maintain Higher product yield.

Description

A high-efficiency combined production method of ultra-low sulfur and high-octane gasoline

technical field

The invention relates to a high-efficiency combined production method of ultra-low sulfur and high-octane gasoline, in particular to a method for catalytic cracking (FCC) gasoline in the field of petroleum refining, especially low-quality FCC gasoline with ultra-high sulfur and high olefins Ultra-deep desulfurization-recovering octane number hydrogenation upgrading method.

Background technique

At present, the high sulfur content and olefin content in FCC gasoline have become the key problems that plague the world's clean gasoline production. In the case of less high-octane reformed gasoline and alkylated gasoline, in order to meet the increasingly stringent clean gasoline standards, FCC gasoline hydro-upgrading has become one of the key technologies for the production of clean fuel for vehicles .

USP 5770047, USP 5417697, etc. introduced the desulfurization and olefin reduction process based on hydrofining-cracking/single-branched hydroisomerization. The main idea of these processes is to cut the whole fraction of FCC gasoline into light and heavy fractions. After the heavy fraction of FCC gasoline is desulfurized by conventional hydrotreating catalysts, all the olefins in it will be converted into alkanes, and then the obtained products will have appropriate acidity after being screened. The alkane cracking-hydroisomerization reaction is completed on the zeolite-based catalyst to achieve the purpose of improving and restoring the octane number, and then the whole fraction of modified gasoline is obtained by blending light and heavy fractions. According to the records of the above-mentioned patents, the liquid yield of the final blended product is 94wt%, and the gasoline research method octane number (RON) loss reaches about 2.0 units.

Although the gasoline hydro-upgrading method provided by the above-mentioned patent can achieve the purpose of desulfurization and olefin reduction, the olefin content in the raw oil it targets is only about 20v% and the aromatic content is relatively high (about 30v%), which is more suitable for Foreign gasoline components, for oil products with high olefin and sulfur content and low aromatic content (about 20v%), such as my country's FCC gasoline with olefin content as high as about 40v%, use this process for upgrading, and in desulfurization While reducing olefins, a large amount of olefins are hydrogenated and saturated, resulting in an increase in the loss of octane number, so these publicly reported upgrading technologies are obviously not applicable. It is for this reason that in view of the particularity of Chinese FCC gasoline, exploring a more scientific and reasonable upgrading method has always been a research hotspot in the oil refining industry.

CN145666A (Chinese Patent Application No. 02121595.2) provides the method of deep desulfurization and olefin reduction of gasoline, which is aimed at the above-mentioned characteristics of my country's FCC gasoline. The heavy gasoline fraction after hydrodesulfurization and denitrogenation and saturated olefins is used for hydrogenation catalysts. The HZSM-5 based octane recovery catalyst with sufficient acidic function can realize the cracking of low-octane alkane molecules and the isomerization reaction of alkane molecules, and then mix the modified heavy fraction with the cut light fraction to form The final modified product. According to the introduction of this patent, since the olefins are completely hydrogenated and saturated in the first stage reaction, in order to restore the octane number of the product, it is necessary to increase the cracking capacity of the second stage catalyst, at the cost of a significant reduction in the product liquid yield (only 86 %), and the processing cost is significantly increased.

CN 1488722A (Chinese Patent Application No. 0213311.1) discloses a FCC gasoline hydro-upgrading process similar to the above-mentioned patent. The difference is that after the heavy fraction of FCC gasoline is deeply desulfurized by conventional hydrorefining catalysts and all olefins are converted into alkanes, the resulting reaction effluent is n-paraffin cracking-single branched chain hydroisomerization completed on a nano-Hβ zeolite-based catalyst reaction.

The similarities between the upgrading processes of the above two Chinese patents are that heavy distillate oil that has undergone conventional hydrotreating is isomerized on an acidic functional zeolite-based catalyst to realize n-paraffin cracking-single branched chain hydroisomerization , because HZSM-5 zeolite and nano-Hβ zeolite have strong acidity and large acid content, the cracking reaction is more serious, and the result is that the single branched chain isomerization reaction of alkanes is inhibited.

CN 1743425A (Chinese Patent Application No. 200410074058.7) discloses a hydrogenation and upgrading process for high-olefin FCC gasoline in my country, wherein, the full-cut FCC gasoline is modified by three reactions of de-diene, olefin aromatization and supplementary olefin reduction. , the desulfurization rate is 78%, the product olefin content is 30v%, the product RON loss is 1.0 unit, and the product liquid yield is about 98.5wt%. However, this method is mainly aimed at low-sulfur FCC gasoline. Under the premise of reducing the loss of RON as much as possible, the desulfurization rate is low and the olefin reduction rate is small. Sulfur content of raw oil.

CN 1488724A (Chinese Patent Application No. 02133130.8) discloses a combined FCC gasoline hydrofinishing/aromatization process based on a nano-zeolite catalyst. The process is to convert most of the olefins into alkanes by hydrotreating the whole fraction of FCC gasoline, and then carry out the aromatization of the alkanes on the nano-zeolite catalyst. The nanoscale hydrogen-type molecular sieve catalyst of metal oxide makes the desulfurization rate of the modified product high and the olefin drop rate is large, but the product liquid yield obtained by this method is only about 90wt%, and the product RON loss is relatively large (reaching 2.0-3.0 units ), and the preparation of nano zeolite is complicated, and the regeneration performance is not good, which leads to an increase in process cost and is difficult to adapt to industrial production.

CN 1718688A (Chinese Patent Application No. 200410020932.9) discloses a method for hydrogenation and upgrading of inferior FCC gasoline. The patented method forms three reaction zones under the conditions of hydrogen presence and temperature gradually increasing, so that the whole distillate FCC gasoline is contacted with three kinds of catalysts ^. ) for dealdiene reaction, and then use nano-zeolite catalyst to carry out aromatization and isomerization reaction at high temperature (415°C), and finally use Co-Mo-KP/Al ₂ O ₃ catalyst at high temperature (415°C) and more Selective desulfurization is carried out at high space velocity (40h ^-1 ). The advantage of this method is that the olefin and sulfur content of the obtained product are all low, but the product RON loss is about 3.0 units, the product liquid yield is about 94wt%, and the preparation of nano zeolite is complicated, easy to deactivate at high temperature, and the regeneration performance In addition, the desulfurization catalyst in the third stage is easily deactivated at very high space velocity and high temperature, which affects the reaction stability of the entire process and increases the difficulty of industrial production.

CN 1597865A (Chinese Patent Application No. 03133992.1) discloses a method for hydrogenation and upgrading of low-quality FCC gasoline similar to CN 1718688A. In this process, a conventional hydrotreating catalyst is used to carry out the deolefination reaction of the whole cut FCC gasoline at a high feed space velocity (6h ^-1 ), and then a Co-Mo-KP/Al ₂ O ₃ catalyst is used for selective desulfurization , and finally use nano-zeolite catalyst to carry out olefin aromatization at high temperature (415°C). The olefin content of the product obtained by this patented method is low, but the RON loss of the product is about 1.0 units. The shortcomings of the above-mentioned nano zeolite still exist, and the sulfur content of the product is high (the desulfurization rate is only 75%), and it is difficult to meet the requirements of National III. And the country Ⅳ clean gasoline standard.

CN 1769388A (Chinese Patent Application No. 200410082704.4) discloses a hydro-upgrading process for reducing the sulfur and olefin content of FCC gasoline. The process of this patent is to use conventional hydrorefining catalyst to carry out the diene reaction of whole fraction FCC gasoline at high feed space velocity (6h ^-1 ), and then carry out pre-fractionation, light fraction gasoline is mainly carried out on nano zeolite catalyst Olefin aromatization, heavy distillate gasoline is sequentially subjected to selective hydrodesulfurization reaction on low metal content alumina catalyst and high metal content alumina catalyst, and finally the reacted light and heavy gasoline can be mixed to obtain whole distillate modified gasoline. The content of olefins and sulfur in the product obtained by this patented method is relatively low, but the RON loss of the product is still about 1.5 units during the entire processing process, and the above-mentioned shortcomings of nano-zeolite still exist, and four catalysts and supporting complex processes are required , limiting its industrial application.

CN1283761C (Chinese Patent No. 200410060574.4) discloses a process for hydrogenation and upgrading of inferior gasoline. In this process, the whole fraction FCC gasoline is first cut into light fraction and heavy fraction gasoline, and then the heavy fraction gasoline is subjected to hydrodesulfurization on Co(Ni)-Mo/ _TiO2 catalyst, and then the Co(Ni)-Mo(W) /ZSM-5-/TiO ₂ catalyst for aromatization, and finally the light and heavy gasoline after the reaction is mixed to become full fraction modified gasoline. The olefin content of the product obtained according to this patented method is relatively low, but the sulfur content of the product is difficult to meet the requirements of the National IV standard of no more than 50 μg.g ^-1 . On the other hand, this method is aimed at high sulfur oil. The RON of the product, one of the keys of this method is to carry out aromatization to the heavy distillate gasoline after hydrodesulfurization, but aromatic hydrocarbon is the precursor of coke, and higher aromatic hydrocarbon generation amount (product aromatic hydrocarbon is higher than raw material more than 10v%) is harmful to The stability of the catalyst is extremely unfavorable; moreover, the catalyst carrier in this method is required to be mainly TiO ₂ , which also greatly reduces the strength of the catalyst, which is not conducive to its long-term stable operation and regeneration.

In short, for low-quality oil products such as my country’s FCC gasoline with high sulfur content and high olefins, although many studies have tried to achieve desulfurization and olefin reduction through different means of upgrading, while maintaining and improving the octane number of the oil as much as possible, Although these published methods have their own advantages, it is necessary to explore a more reasonable upgrading process, select a catalyst with appropriate function and activity, achieve ultra-deep desulfurization and greatly reduce olefins while maintaining octane number, and solve the problem of catalyst stability. Problems such as unsatisfactory performance and high processing costs have always been the goals pursued by the field of petroleum refining.

Contents of the invention

Aiming at the deficiencies in the prior art, the purpose of the present invention is to provide a high-efficiency combined production method for ultra-low sulfur and high-octane gasoline, by contacting low-quality full-cut gasoline feedstock with a low-temperature directional sulfur transfer catalyst under hydrogen-facing conditions, Convert lighter mercaptans and thiophene sulfur compounds into high-boiling sulfur compounds and transfer them to heavier gasoline fractions, and then cut the fractions of inferior full-distillate gasoline that has undergone sulfur transfer treatment; and then treat heavy distillate gasoline , and finally blend the light distillate gasoline with the treated heavy distillate gasoline to obtain ultra-low sulfur and high octane gasoline. The method is applicable to the upgrading of low-quality gasoline with ultra-high sulfur and high olefins, and can achieve ultra-deep desulfurization and olefin reduction for low-quality gasoline, while improving the product octane number and maintaining a high product liquid yield.

In order to achieve the above object, the present invention provides a high-efficiency combined production method for ultra-low sulfur and high-octane gasoline, which mainly includes:

Make low-quality full-distillate gasoline raw materials undergo low-temperature directional sulfur transfer reaction under hydrogen-facing conditions, and then conduct oil cutting and fractionation to obtain light-distillate gasoline and heavy-distillate gasoline. The cutting and fractionation temperature is 50-90°C;

Contacting heavy distillate gasoline with a selective hydrodesulfurization catalyst and a make-up desulfurization-hydrocarbon isomerization/aromatization catalyst;

Blending light distillate gasoline and treated heavy distillate gasoline to obtain ultra-low sulfur and high octane gasoline products.

In the high-efficiency combined production method of ultra-low-sulfur and high-octane gasoline provided by the present invention, firstly, the raw material of inferior full-distillate gasoline is contacted with a low-temperature directional sulfur transfer catalyst under the condition of hydrogen, and the lighter mercaptan and thiophene Sulfur-like compounds are converted into high-boiling sulfur compounds and transferred to heavier gasoline fractions, and then cut the inferior full-distillate gasoline that has undergone sulfur transfer treatment to obtain light-distillate gasoline and heavy-distillate gasoline; then make the heavy-distillate gasoline first Contact with selective hydrodesulfurization catalysts for desulfurization, remove sulfur compounds such as sulfides, alkylthiophenes, and benzothiophenes, and then contact with supplementary desulfurization-hydrocarbon isomerization/aromatic catalysts to further remove sulfur compounds such as thiophene sulfur and restore the octane number of the product through the isomerization/aromatization effect; finally, the light-distillate gasoline and the treated heavy-distillate gasoline are mixed to obtain ultra-low sulfur and high-octane gasoline products.

The low-quality gasoline suitable for the production method of ultra-low sulfur and high-octane gasoline provided by the present invention may include one or more of catalytic cracking gasoline, coker gasoline, catalytic cracking gasoline, thermal cracking gasoline and steam cracking gasoline, etc. Mixtures, especially low-quality FCC gasoline with ultra-high sulfur and high olefins.

In the high-efficiency combined production method of ultra-low sulfur and high-octane gasoline provided by the present invention, the low-temperature directional sulfur transfer reaction is to make sulfur compounds such as low-boiling mercaptans and thiophenes pass through and olefins (not only diolefins, but also monoolefins) ) between etherification, alkylation and other reactions to make it heavier and transferred to gasoline heavy fractions. The low-temperature directional sulfur transfer reaction can be realized by contacting gasoline feedstock with a sulfur transfer catalyst under hydrogen-facing conditions. Preferably, the reaction conditions for the low-temperature directional sulfur transfer reaction are: reaction pressure 1-3 MPa, liquid volume space velocity 2-8 h ^-1 , reaction temperature 100-220°C, hydrogen-oil volume ratio 200-600.

In the high-efficiency combined production method of ultra-low sulfur and high-octane gasoline provided by the present invention, low-boiling sulfur compounds such as mercaptans and thiophenes are made heavy into gasoline heavy fractions through low-temperature directional sulfur transfer reaction of gasoline raw materials, Therefore, the gasoline light fraction obtained after cutting can meet the requirements of the clean gasoline standard without further treatment, which saves the catalyst and investment by eliminating the step of processing the gasoline light fraction. Moreover, the low-temperature directional sulfur transfer reaction is carried out in the fixed-bed reactor before the cutting tower, so that the sulfur transfer and gasoline fraction cutting are carried out separately, which can avoid the mutual influence of the two and ensure the stable control of the reaction conditions, so that the low-boiling point sulfur compounds can be efficiently transferred to the heavy fraction.

In the high-efficiency combined production method of ultra-low sulfur and high-octane gasoline provided by the present invention, preferably, the reaction conditions of heavy distillate gasoline on the selective hydrodesulfurization catalyst (selective hydrodesulfurization reaction conditions of heavy distillate gasoline) It is: reaction pressure 1-3MPa, liquid volume space velocity 3-6h ^-1 , reaction temperature 200-300°C, hydrogen-to-oil volume ratio 200-600; The reaction conditions (supplementary desulfurization of heavy distillate gasoline-hydrocarbon isomerization/aromatization reaction conditions) are: reaction pressure 1-3MPa, liquid volume space velocity 1-4h ^-1 , reaction temperature 340-430°C, hydrogen-oil volume ratio 200-600.

In the high-efficiency combined production method of ultra-low-sulfur and high-octane gasoline provided by the present invention, a sulfur-transfer catalyst is used to carry out directional sulfur transfer on low-quality full-cut gasoline, so that sulfur compounds such as low-boiling mercaptans and thiophenes are converted into high-boiling point sulfur compounds. Sulfur compounds are transferred to gasoline heavy fractions, which can ensure that the sulfur content in light fractions is greatly reduced and can meet the requirements of clean gasoline standards. Based on the total weight of the catalyst, the composition of the sulfur transfer catalyst in the above directional sulfur transfer reaction includes: 2-30% of transition metal oxides, 0.5-6% of additives, 10-40% of zeolites, and the balance is inorganic refractory oxides . Wherein, the above-mentioned transition metal oxide is one or more of NiO, CoO, ZnO, MoO ₃ , WO ₃ and CuO, etc.; the above-mentioned auxiliary agent is one or more of K ₂ O, MgO, La ₂ O _{3 ,} etc. Several kinds; the above-mentioned zeolite is one or more of HZSM-5, Hβ and HY, etc., and the zeolite is a zeolite that has undergone alkali treatment, ammonium exchange, and hydrothermal treatment in sequence; the above-mentioned inorganic refractory oxide is alumina (pure oxide One or more of aluminum), silicon oxide, and silicon-containing aluminum oxide. The specific preparation method of the sulfur transfer catalyst can be, for example, mixing alkali treatment-ammonium exchange-hydrothermal treatment zeolite and inorganic oxides, adding a binder, extruding through an extruder, drying, and roasting to prepare a catalyst carrier , and then use the impregnation method to load transition metals and additives, and then obtain the required sulfur transfer catalyst after drying and roasting.

In the high-efficiency combined production method of ultra-low sulfur and high-octane gasoline provided by the present invention, for heavy distillate gasoline, a selective hydrodesulfurization catalyst is first used for hydrogenation reaction to remove sulfides, alkylthiophenes, and benzothiophenes. and other sulfides, based on the total weight of the catalyst, the weight composition of the above selective hydrodesulfurization catalyst includes: MoO ₃ 10-18%, CoO2-6%, K ₂ O 1-7% and P ₂ O ₅ 2-6% , the balance is Al-Si-Mg composite oxide carrier, and the weight composition of Al-Si-Mg composite oxide in the catalyst is Al ₂ O ₃ 60-75%, SiO ₂ 5-15% and MgO 3-10 %.

In the high-efficiency combined production method of ultra-low sulfur and high-octane gasoline provided by the present invention, after selective hydrodesulfurization of heavy distillate gasoline, the effluent is contacted with a supplementary desulfurization-hydrocarbon isomerization/aromatization catalyst, Further remove sulfides such as thiophene sulfur, and restore the octane number of the product through the isomerization/aromatization effect. Based on the total weight of the catalyst, the weight composition of the above supplementary desulfurization-hydrocarbon isomerization/aromatization catalyst includes: MoO ₃ 4- 8%, CoO 1-4%, P ₂ O ₅ 1-3%, modified HZSM-5 zeolite 50-70%, and the balance is Al-Ti composite oxide binder; among them, Al-Ti composite oxide The weight composition of the binder includes: 70-95% of Al ₂ O ₃ and 5-30% of TiO ₂ . The above-mentioned modified HZSM-5 zeolite can be prepared according to the following method: under the conditions of a temperature of about 500-700°C and a water vapor space velocity of about ^1-4h Heat treatment: using an inorganic acid solution with a pH value of 1.0-4.0, pickling the hydrothermally treated product at about 50-90°C for 1-4 hours, wherein the liquid-solid ratio of the inorganic acid solution to the hydrothermally treated product is about 5 -10mL/g; then the acid-washed product is washed, filtered, dried at 100-120°C for 2-4 hours, and calcined at 500-550°C for 4-6 hours to prepare a modified HZSM-5 zeolite. The SiO ₂ /Al ₂ O ₃ molar ratio of the HZSM-5 zeolite may be 30-60, preferably 35-50; the inorganic acid may be one or more of nitric acid, sulfuric acid and hydrochloric acid.

According to the usual expressions in the field of catalysts, the content of active components (elements) on the carrier and catalyst mentioned in the present invention are all calculated by their corresponding oxides.

The ultra-clean gasoline production method provided by the present invention can obtain a good hydrogenation modification effect on low-quality gasoline with ultra-high sulfur and high olefins (such as FCC gasoline), for example: sulfur content of 1000-2500 μg.g ^-1 , olefins Low-quality gasoline with a content of 40-45v%.

Compared with the prior art, the high-efficiency combined production method of ultra-low sulfur and high-octane gasoline provided by the present invention has the following characteristics:

(1) Low-quality gasoline with a sulfur content of 1000-2500μg.g ^-1 and an olefin content of 40-45v% can be modified into a gasoline with a sulfur content of ≤10μg.g ^-1 , an olefin content of ≤20v%, and a gasoline research method octane number (RON) loss ≤ 1.0 units of high-quality gasoline, and product liquid yield ≥ 98wt%;

(2) The heat can be fully utilized and easy to operate. The outlet product temperature of the heavy-distillate gasoline reforming reactor is relatively high, and the heat can be utilized by exchanging heat with untreated heavy-distillate gasoline raw materials;

(3) In the above-mentioned method of the present invention, at first carry out directional sulfur transfer reaction to inferior whole cut gasoline, then obtain light cut gasoline and heavy cut gasoline by fractional distillation of the inferior full cut gasoline after sulfur transfer treatment, then carry out heavy cut gasoline Sequentially carry out selective hydrodesulfurization and supplementary desulfurization-hydrocarbon isomerization/aromatics treatment. These multiple reactions are beneficial to realize the effects of ultra-deep desulfurization, olefin reduction and octane recovery of full-cut inferior gasoline;

(4) The high-efficiency combined production method of gasoline provided by the present invention is especially suitable for upgrading low-quality gasoline with ultra-high sulfur and high olefin content. It can improve its octane number and maintain a higher octane number while ultra-deep desulfurization and olefin reduction Therefore, compared with foreign gasoline hydrogenation and upgrading methods, the above-mentioned gasoline high-efficiency combined production method provided by the present invention is more suitable for processing inferior gasoline components in my country.

Description of drawings

Fig. 1 is a schematic flow diagram of the high-efficiency combined production method for ultra-low sulfur and high-octane gasoline provided by the present invention.

Detailed ways

In order to have a clearer understanding of the technical features, purposes and beneficial effects of the present invention, the technical solution of the present invention is described in detail below, but it should not be construed as limiting the scope of implementation of the present invention.

Example 1

This example provides an ultra-high-sulfur, high-olefin low-quality full-fraction FCC gasoline (full-fraction feedstock 1) with a sulfur content of 1750 μg.g ^-1 and an olefin content of 48.4v% as a raw material for hydroreforming treatment An efficient combined production method for producing ultra-low sulfur and high-octane gasoline.

Wherein, the composition ratio of various catalysts is as follows, respectively based on the total weight of each catalyst:

Sulfur transfer catalyst: 12wt% NiO-6wt% MoO ₃ -2wt% La ₂ O ₃ /20wt% HZSM-5-60wt% (Al ₂ O ₃ -SiO ₂ ) (silicon-containing alumina);

Selective hydrodesulfurization catalyst: 4wt%CoO- _12wt % _MoO3-3wt % _K2O -2wt% _P2O5 / _67wt %Al2O3-8wt% _SiO2-4wt %MgO _:

Supplementary desulfurization-hydrocarbon isomerization/aromatization catalyst: 2wt%CoO-6wt% _MoO3-1wt % _P2O5 / _65wt %HZSM- _5-21wt % _Al2O3-5wt % _TiO2 .

The specific preparation steps of sulfur transfer catalyst (catalyst 1) are as follows:

First, put HZSM-5 zeolite (SiO ₂ /Al ₂ O ₃ molar ratio is 30) in NaOH aqueous solution at a liquid-solid ratio of 10 mL/g, adjust the pH value to 13, stir at 75°C for 4 hours, filter, The filtered zeolite was washed to neutrality and dried at 120° C. for 3 hours; the HZSM-5 zeolite treated with NaOH aqueous solution was mixed according to the ratio of zeolite: ammonium nitrate: water in a weight ratio of 1:0.8:10, and mixed at 80 ℃ and stirred for 4 hours, then the product was filtered, washed, dried at 120 ℃, and calcined at 480 ℃ for 4 hours to obtain alkali-treated-ammonium-exchanged HZSM-5 zeolite; the above-mentioned alkali-treated and ammonium-exchanged HZSM-5 zeolite Passing steam at 600°C for 20-50 minutes to obtain a modified HZSM-5 zeolite (alkali treatment-ammonium exchange-hydrothermal treatment HZSM-5 zeolite);

Weigh 50.2g of silica-alumina powder (containing Al ₂ O ₃ 92.0wt%, SiO ₂ 8.0wt%), 30.0g of the above-mentioned modified HZSM-5 zeolite, 2.5g of squash powder, grind and mix them evenly, add 6mL mass Concentration is 65% nitric acid solution, after fully kneading, extrude clover-shaped strips with a diameter of 2mm in the extruder, dry at 120°C for 4 hours, and bake at 520°C for 4 hours to obtain a shaped catalyst carrier;

Prepare a mixed solution of nickel nitrate, ammonium molybdate, and lanthanum nitrate containing NiO, MoO ₃ and La ₂ O ₃ according to the stoichiometric ratio, and then uniformly drop the impregnation solution onto the above-mentioned catalyst carrier by an equal-volume impregnation method, and dry at 120°C After calcination at 520° C. for 4 hours for 4 hours, catalyst I was prepared.

The concrete preparation steps of selective hydrodesulfurization catalyst (catalyst II) are as follows:

Weigh 70g of Al-Si-Mg composite powder (water content 25wt%) and 2g of scallop powder with suitable Al/Si/Mg ratio, grind and mix them evenly, add 5mL of nitric acid solution with a mass concentration of 65%, and fully knead Afterwards, extrude into a strip in an extruder, dry at 120°C for 3 hours, and bake at 520°C for 4 hours to obtain a shaped catalyst carrier;

Immerse 40g of the catalyst carrier above in 35mL of a mixed impregnation solution of potassium nitrate and diammonium hydrogen phosphate, which contains 1.5g K ₂ O and 1.0g P ₂ O ₅ in terms of oxides, and then age at room temperature Treat for 5 hours, then dry at 120°C for 3 hours, and bake at 520°C for 4 hours to obtain a catalyst carrier loaded with potassium and phosphorus;

Prepare 32.0mL of cobalt nitrate and ammonium molybdate mixed solution containing 2.0gCoO and 6.1gMoO ₃ (the content of each active component is calculated in the form of oxide, and the active component in the mixed solution is not limited to exist in the form of oxide), and add 3.0mL ammonia water with a mass concentration of 17%, fully shake until the solid is completely dissolved to make an impregnation solution, then impregnate the catalyst carrier loaded with potassium and phosphorus in the impregnation solution, age at room temperature for 5 hours, and dry at 120°C After 3 hours and 520°C calcination treatment for 5 hours, the catalyst II was prepared.

Supplementary desulfurization-hydrocarbon isomerization/aromatization catalyst (catalyst III) can be prepared according to the method described in CN101508912A (application number is 200910080112.1) (the full text of CN101508912A is incorporated here as a reference), the difference is the preparation method disclosed in CN101508912A Inorganic acid-organic acid treatment after reclaimed hydrothermal treatment was changed to single inorganic acid treatment after hydrothermal treatment (the treatment conditions were the same).

The process of producing ultra-low-sulfur and high-octane gasoline by upgrading whole-distillate feedstock 1 is as follows, and the process flow is shown in Figure 1:

The raw oil product to be treated is full distillate raw oil 1, and its properties are shown in Table 1. The ultra-high-sulfur low-quality full-fraction feedstock 1 first performs directional sulfur transfer reaction on a low-temperature sulfur transfer catalyst (catalyst I). The sulfur transfer reaction conditions are: reaction pressure 2 MPa, liquid volume space velocity 5 h ^-1 , reaction temperature 160 °C, The volume ratio of hydrogen to oil is 400; then the inferior full-distillate gasoline after the sulfur transfer reaction enters the cutting tower to obtain light-distillate gasoline and heavy-distillate gasoline, and the cutting and fractionating temperature of gasoline is 70°C;

The heavy distillate gasoline adopts simple series operation and is carried out on a device with two reactors connected in series. In the first reactor, it contacts with Catalyst II, and a selective hydrodesulfurization reaction occurs. The reaction conditions are: reaction pressure 1.8MPa, liquid volume The space velocity is 3h ^-1 , the reaction temperature is 220°C, and the volume ratio of hydrogen to oil is 300; in the second reactor, it is in contact with catalyst III, and desulfurization-hydrocarbon isomerization/aromatization reaction occurs. The reaction conditions are: reaction pressure 1.8MPa, The liquid volume space velocity is 1.7h ^-1 , the reaction temperature is 360°C, and the volume ratio of hydrogen to oil is 300;

After the above reaction is completed, the light distillate gasoline and the treated heavy distillate gasoline are mixed to obtain a blend product of light distillate gasoline and heavy distillate gasoline, that is, ultra-low-sulfur high-octane gasoline.

During the reaction process, all catalysts were diluted with porcelain sand, and after the airtightness of each reactor or reaction device was qualified, the catalyst was pre-sulfurized by conventional pre-sulfurization process, and after 400 hours of reaction, sampling and analysis were performed. Table 1 gives the property parameters of the reaction modified products.

As can be seen from Table 1, the upgrading method of the present invention can reduce the sulfur content of inferior FCC gasoline from 1750 μg.g ^-1 to 5 μg.g ^-1 , the olefin content from 48.4v% to 19.8v%, and the product The content of isoparaffin and aromatics has increased significantly, the content of isoparaffins has increased from 17.4v% to 25.9v%, and the content of aromatics has increased from 16.3v% to 25.7v%. The octane number of the product research method is increased by 0.2 units, the yield of the blended gasoline product is 98.8wt%, and the product quality meets the requirements of the National V clean gasoline standard.

Table 1 The property parameters of whole distillate feed oil 1 and modified light and heavy distillate gasoline blending products

project  Full Distillate Feed Oil 1 Light and heavy distillate gasoline blending products Yield (wt%) - 98.8 Density (g/mL) 0.735 0.737 Distillation range (℃) 33-204 32-208 Typical hydrocarbon content (v%) Isoparaffins 17.4 25.9 Olefins 48.4 19.8 Aromatics 16.3 25.7 Sulfur (μg·g ^-1 ) 1750 5 Dienes (gl/100g) 2.4 0.0 RON 91.3 91.5

Example 2

This example provides an ultra-high-sulfur, high-olefin low-quality full-fraction FCC gasoline (full-fraction feedstock 2) with a sulfur content of 2210 μg·g ^-1 and an olefin content of 51.3v% as a raw material for hydroreforming treatment An efficient combined production method for producing ultra-low sulfur and high-octane gasoline.

Wherein, the composition ratio of various catalysts is as follows, respectively based on the total weight of each catalyst:

Sulfur transfer catalyst: 10wt% NiO-7wt% MoO ₃ -2wt% K ₂ O-2wt% CuO/35wt% HZSM-5-44wt% (Al ₂ O ₃ -SiO ₂ ) (silicon-containing alumina);

Selective hydrodesulfurization catalyst: 3wt%CoO-14wt% _MoO3-3wt % _K2O - _3wt % _P2O5 / _67wt %Al2O3-5wt% _SiO2-5wt %MgO _:

Supplementary desulfurization-hydrocarbon isomerization/aromatization catalyst: 2.5wt% CoO-8wt% MoO ₃ -3wt% P ₂ O ₅ /60wt% HZSM-5-23.5wt% _{Al 2} O ₃ -3wt% TiO ₂ ;

The preparation method of above-mentioned catalyst is identical with embodiment 1.

The process of producing ultra-low-sulfur and high-octane gasoline by upgrading whole-distillate feedstock 2:

The raw material oil product adopts the whole distillate raw material oil 2, and its properties are referred to in Table 2, and the reaction device setting and the treatment of the catalyst etc. are all the same as in Example 1, and the specific reaction conditions are as follows:

The sulfur transfer reaction conditions are: reaction pressure 1.6MPa, liquid volume space velocity 4h ^-1 , reaction temperature 140°C, hydrogen-oil volume ratio 300;

Gasoline cutting fractionation temperature is 60°C;

The reaction conditions for selective hydrodesulfurization of heavy distillate gasoline are: reaction pressure 2MPa, liquid volume space velocity 4h ^-1 , reaction temperature 240℃, hydrogen-oil volume ratio 400;

The reaction conditions for supplementary desulfurization of heavy distillate gasoline-hydrocarbon isomerization/aromatization reaction are: reaction pressure 2MPa, liquid volume space velocity 2h ^-1 , reaction temperature 375°C, hydrogen-oil volume ratio 400.

Table 2 shows the property parameters of the modified reaction products.

Table 2 The property parameters of whole distillate feed oil 2 and modified light and heavy distillate gasoline blending products

project Full distillate feed oil 2 Light and heavy distillate gasoline blending products Yield (wt%) - 98.6 Density (g/mL) 0.746 0.749 Distillation range (℃) 35-206 33-211 Typical hydrocarbon content (v%) Isoparaffins 19.5 30.5 Olefins 51.3 18.9 Aromatics 18.1 27.8 Sulfur (μg.g ^-1 ) 2210 8 Dienes (gl/100g) 3.5 0.0 RON 92.4 92.3

As can be seen from Table 2, the upgrading method of the present invention can reduce the sulfur content of inferior FCC gasoline from 2210 μg.g ^-1 to 8 μg.g ^-1 , the olefin content from 51.3v% to 18.9v%, and the product The content of isoparaffin and aromatics has increased significantly, the content of isoparaffins has increased from 19.5v% to 30.5v%, and the content of aromatics has increased from 18.1v% to 27.8v%. The octane number of the research method is only reduced by 0.1 unit, the yield of the blended gasoline product is 98.6wt%, and the product quality meets the requirements of the National V clean gasoline standard.

The above two examples show that the high-efficiency combined production method of ultra-low-sulfur and high-octane gasoline provided by the present invention can modify ultra-high-sulfur, high-olefin low-quality feed oil into sulfur content ≤ 10 μg.g ^-1 , olefin Content ≤ 20v%, gasoline research method octane number (RON) loss ≤ 1.0 units of national V ultra-clean gasoline products show that the method of the present invention has a good hydrogenation and upgrading effect on low-quality gasoline, and will be the first choice for China's oil refining industry Lay the foundation for further development.

The specific embodiments described above have further described the purpose, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above descriptions are only specific embodiments of the present invention and are not intended to limit the scope of the present invention. Protection scope, within the spirit and principles of the present invention, any modification, equivalent replacement, improvement, etc., shall be included in the protection scope of the present invention.

Claims (5)

1. A high-efficiency combined production method for ultra-low sulfur and high-octane gasoline, the method comprising: The low-quality full-distillate gasoline raw material is subjected to low-temperature directional sulfur transfer reaction under the condition of hydrogen, and then the oil product is cut and fractionated to obtain light-distillate gasoline and heavy-distillate gasoline. The cut-off fractionation temperature is 50-90°C; The reaction conditions are: reaction pressure 1-3M _Pa , liquid volume space velocity 2-8h ^-1 , reaction temperature 100-220°C, hydrogen-oil volume ratio 200-600; Make the heavy distillate gasoline contact with the selective hydrodesulfurization catalyst and supplementary desulfurization-hydrocarbon isomerization/aromatic catalyst; the reaction conditions of the heavy distillate gasoline on the selective hydrodesulfurization catalyst are: reaction pressure 1-3MPa , liquid volume space velocity 3-6h ^-1 , reaction temperature 200-300°C, hydrogen-to-oil volume ratio 200-600; the reaction conditions of the heavy distillate gasoline on supplementary desulfurization-hydrocarbon isomerization/aromatization catalyst are: reaction Pressure 1-3MPa, liquid volume space velocity 1-4h ^-1 , reaction temperature 340-430℃, hydrogen-oil volume ratio 200-600; Blend light distillate gasoline with treated heavy distillate gasoline to obtain ultra-low sulfur and high octane gasoline products; Wherein, based on the total weight of the catalyst, the composition of the sulfur transfer catalyst in the low-temperature directional sulfur transfer reaction includes: transition metal oxide 2-30%, additive 0.5-6%, zeolite 10-40%, and the balance is inorganic refractory oxides; and, The transition metal oxide is one or more of NiO, CoO, ZnO, MoO ₃ , WO ₃ and CuO; _The auxiliary agent is one or more of _K2O , MgO and _La2O3 ; The zeolite is one or more of HZSM-5, Hβ, and HY, and the zeolite is a zeolite that has undergone alkali treatment, ammonium exchange, and hydrothermal treatment in sequence; The inorganic refractory oxide is one or more of alumina, silicon oxide and silicon-containing alumina; Based on the total weight of the catalyst, the composition of the selective hydrodesulfurization catalyst includes: MoO ₃ 10-18%, CoO2-6%, K ₂ O 1-7% and P ₂ O ₅ 2-6%, and the balance is Al - Si-Mg composite oxide carrier, and the weight composition of Al-Si-Mg composite oxide in the catalyst is: Al ₂ O ₃ 60-75%, SiO ₂ 5-15% and MgO3-10%; Based on the total weight of the catalyst, the composition of the supplementary desulfurization-hydrocarbon isomerization/aromatization catalyst includes: MoO ₃ 4-8%, CoO 1-4%, P ₂ O ₅ 1-3%, modified HZSM-5 zeolite 50-70%, the balance is Al-Ti composite oxide binder. 2. The production method according to claim 1, wherein the weight composition of the Al-Ti composite oxide binder comprises: Al ₂ O ₃ 70-95%, TiO ₂ 5-30%. 3. The production method according to claim 1, wherein the modified HZSM-5 zeolite in the composition of the supplementary desulfurization-hydrocarbon isomerization/aromatic catalyst is prepared according to the following method: Under the conditions of 500-700°C and water vapor space velocity of 1-4h ^-1 , perform hydrothermal treatment on HZSM-5 zeolite for 15-50 minutes; Use an inorganic acid solution with a pH value of 1.0-4.0 to pickle the hydrothermally treated product at 50-90°C for 1-4 hours, wherein the liquid-solid ratio of the inorganic acid solution to the hydrothermally treated product is 5-10mL/g ; The modified HZSM-5 zeolite is prepared by washing, filtering, drying at 100-120° C. for 2-4 hours, and roasting at 500-550° C. for 4-6 hours on the acid-washed product. 4. The production method according to claim 3, wherein the SiO ₂ /Al ₂ O ₃ molar ratio of the HZSM-5 zeolite is 30-60; the inorganic acid is one of nitric acid, sulfuric acid and hydrochloric acid or Several kinds. 5. The production method according to claim 4, wherein the SiO ₂ /Al ₂ O ₃ molar ratio of the HZSM-5 zeolite is 35-50.

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