Method and device for producing ultra-clean gasoline by coupling fischer-tropsch synthetic oil product and methanol

Abstract

This invention provides a method and apparatus for producing ultra-clean gasoline by coupling Fischer-Tropsch synthetic petroleum products with methanol. The method involves coupling the cracking and aromatization reactions of Fischer-Tropsch synthetic petroleum products with methanol. The resulting light gasoline rich in tertiary olefins and C4 components are then etherified with methanol. The resulting liquefied petroleum gas (LPG) is then alkylated. Finally, the cracked and aromatized heavy gasoline fraction, the etherified light gasoline fraction, methyl tert-butyl ether, and the alkylated gasoline fraction are directly blended to obtain the final clean gasoline product. The method of this invention produces a blended clean gasoline with high overall yield and octane number, low sulfur and aromatic content, and significantly reduced exhaust emissions in engines, exhibiting excellent clean performance.

Description

Technical Field

[0001] This invention belongs to the field of Fischer-Tropsch synthetic oil processing, and relates to a method for producing gasoline from Fischer-Tropsch synthetic oil and an apparatus for implementing the method. Specifically, it relates to a method for producing ultra-clean gasoline by coupling Fischer-Tropsch synthesis with methanol and an apparatus for implementing the method. Background Technology

[0002] Both coal-to-methanol technology and coal indirect liquefaction technology (Fischer-Tropsch synthesis) are technologies that use coal as raw material to produce liquid hydrocarbons from syngas obtained through coal gasification. Because the syngas is purified in the syngas treatment unit, the products of these two technologies are inherently clean, containing no sulfur or nitrogen. Given the global scarcity of oil resources and the urgent need for clean energy for environmental protection, their downstream processing routes have emerged.

[0003] Coal-to-methanol (CTM) is a traditional and mature technology, holding a leading position globally. Previously, methanol was primarily used for the oxidation of formaldehyde and formic acid. With the development of C1 chemistry, the synthesis of ethylene glycol, ethanol, and acetaldehyde from methanol has gained increasing attention. However, in recent years, due to methanol overcapacity, global oil resource scarcity, and the urgent need for clean energy for environmental protection, methanol-to-gasoline (MTG) technology has gradually matured. Mobil was the first to propose the MTG process, which uses coal or natural gas to produce syngas, then uses syngas to produce methanol, and finally uses methanol to produce gasoline under the action of a catalyst. Currently, the MTG fixed-bed process technology from ExxonMobil has been industrialized, consuming 2.7-2.9 tons of methanol per ton of gasoline, with a gasoline yield of 34-35%. The product gasoline has an octane rating of 93, is sulfur-free, lead-free, and low in olefins. MTG is a strongly exothermic process. The fixed-bed process uses a large amount of low-carbon hydrocarbon circulation to control the temperature rise of the reaction bed, resulting in high energy consumption. Subsequently, many researchers conducted fluidized bed studies, which better solved the heat transfer problem, but the gasoline yield is lower.

[0004] In Fischer-Tropsch synthetic petroleum products, components with a distillation range above 150°C account for over 80%. Current industrialized coal indirect liquefaction technologies primarily convert these components into clean diesel blending components through hydrorefining and hydrocracking. However, there are relatively few reports on technologies for converting this fraction into gasoline, mainly including the following patents:

[0005] CN106609154B discloses a method for producing gasoline from Fischer-Tropsch synthetic oils. This method employs a parallel dual-reactor system to process the Fischer-Tropsch synthetic oils. The first reactor is a riser reactor, using a cracking catalyst containing octahedral zeolite and five-membered ring high-silica zeolite (preferably phosphorus- and tungsten-modified ZSM-5) to process Fischer-Tropsch synthetic oil fractions with a distillation range of 200–750°C. The second reactor is a riser reactor, fluidized bed reactor, moving bed reactor, downflow reactor, or a combination of these, using a mixed catalyst of spent and regenerated catalysts as an aromatization catalyst to process self-produced liquefied petroleum gas (LPG) and / or gasoline fractions. The gasoline obtained by this method has an octane rating (RON) between 89.1 and 93.1, but the gasoline yield is below 66.2%.

[0006] CN109694741A discloses a method for producing clean gasoline from Fischer-Tropsch synthetic wax. The method first involves cracking the Fischer-Tropsch synthetic wax to obtain cracked gasoline. The obtained gasoline is then fractionated to obtain rich gas, light gasoline fraction, heavy gasoline fraction, diesel fraction, and recycled oil. The light gasoline fraction undergoes hydroisomerization to obtain isomerized gasoline fraction. The rich gas is separated to obtain isobutane and butene, which are then alkylated to obtain alkylated gasoline fraction. The obtained heavy gasoline fraction, isomerized gasoline fraction, and alkylated gasoline fraction are blended to obtain the final clean gasoline. CN109694742A describes a process where the light gasoline fraction from Fischer-Tropsch synthesis wax cracking is aromatized to obtain an aromatized gasoline fraction; the rich gas is separated to obtain isobutane, n-butene, and isobutene; the isobutane and n-butene are alkylated to obtain an alkylated gasoline fraction; the isobutene is selectively alkylated and hydrogenated to obtain a quasi-alkylated gasoline fraction; and the obtained heavy gasoline fraction, aromatized gasoline fraction, alkylated gasoline fraction, and quasi-alkylated gasoline fraction are blended to obtain the final clean gasoline. CN109694743A describes a process where the light gasoline fraction from Fischer-Tropsch synthesis wax cracking is hydroisomerized to obtain an isomerized gasoline fraction. The rich gas is separated to obtain isobutane, n-butene, and isobutene. The isobutane and n-butene are then alkylated to obtain an alkylated gasoline fraction. The obtained isobutene undergoes selective smothering-hydrogenation to obtain a near-alkylated gasoline fraction. The resulting heavy gasoline fraction, isomerized gasoline fraction, alkylated gasoline fraction, and near-alkylated gasoline fraction are blended to obtain the final clean gasoline. These three methods can produce clean gasoline meeting the China VI standard, with an olefin content of less than 15v%, an aromatic content of less than 35v%, a sulfur content of less than 10μg / g, and a research octane number of 91.0-94.5. The Fischer-Tropsch synthesis wax cracking reaction is carried out in a riser reactor. The active components of the cracking catalyst are rare earth-modified Y-type molecular sieve and ZSM-5 molecular sieve, with a mass ratio of (4-9):1. This series of methods can achieve a total gasoline yield between 70.0% and 84.18%, but it requires the integration of multiple gasoline processing technologies, and the octane ratings of the integrated blended gasoline are all below 95. If a higher octane rating is desired in the single-pass conversion, the proportion of high-octane components needs to be increased, which inevitably reduces the proportion of low-octane components and lowers the total gasoline yield. Therefore, how to simultaneously achieve a high gasoline yield and a high octane rating greater than 95 in a single-pass conversion remains an unsolved technical challenge in this field.

[0007] CN109762597A discloses a method for preparing gasoline blending components from Fischer-Tropsch synthesis oil phase products. This method involves atomizing the Fischer-Tropsch synthesis oil phase products and first reacting them with a low-activity catalyst in the lower part of the reactor for cracking, followed by an aromatization reaction with a high-activity catalyst in the upper part of the reactor. The resulting reaction products are then separated into oil and catalyst, and the oil phase is collected and fractionated to obtain the gasoline blending components. This method can increase the octane number (RON) of the product gasoline to above 95 by controlling the depth of the cracking reaction and the aromatization reaction of the olefin intermediates. However, the gasoline yield from a single-pass conversion of the Fischer-Tropsch synthesis oil is below 57.9%.

[0008] Based on the published patents, methanol-to-gasoline technology has a low gasoline yield, and the Fischer-Tropsch synthesis technology for producing gasoline also follows the traditional petroleum refining approach of catalytic cracking to produce gasoline, mainly using riser or fluidized bed reaction processes. However, it suffers from problems such as low single-pass gasoline yield, low product gasoline octane number, or the need to integrate other gasoline processing processes to ensure the gasoline octane number. The resulting blended clean gasoline is difficult to achieve both high gasoline yield and a high octane number greater than 95 at the same time. Summary of the Invention

[0009] To address the aforementioned problems, the present invention aims to provide a method and apparatus for generating ultra-clean gasoline by coupling Fischer-Tropsch synthetic petroleum products with methanol. The method involves coupling the cracking and aromatization reactions of Fischer-Tropsch synthetic petroleum products with methanol. The resulting light gasoline rich in tertiary olefins and C4 components are then etherified with methanol. The resulting liquefied petroleum gas (LPG) undergoes alkylation. Finally, the cracked and aromatized heavy gasoline fraction, the etherified light gasoline fraction, methyl tert-butyl ether, and the alkylated gasoline fraction are directly blended to obtain the final clean gasoline product. The gasoline product obtained by the method according to the present invention meets the clean gasoline standard, with a total gasoline yield of over 83% and an octane number greater than 95. Compared with conventional petroleum-based commercially available gasoline, the gasoline obtained by this method has a higher octane number, lower sulfur content, lower aromatic content, and significantly reduced exhaust emissions in engines, exhibiting superior clean performance.

[0010] Specifically, the above-mentioned objective of the present invention is achieved through the following aspects:

[0011] In one aspect, the present invention provides a method for producing ultra-clean gasoline by coupling Fischer-Tropsch synthetic oils with methanol, wherein the method includes the following steps:

[0012] (1) Fischer-Tropsch synthetic oil is preheated, atomized and then mixed with methanol and fed into the cracking aromatization reaction unit to carry out the cracking aromatization reaction to obtain cracking aromatization products;

[0013] (2) The above-mentioned cracking aromatization products are fed into the oil and gas fractionation unit for oil and gas fractionation to obtain cracking aromatization gas products, cracking aromatization light gasoline fraction, cracking aromatization heavy gasoline fraction, cracking aromatization diesel fraction and cracking aromatization heavy oil fraction, wherein the cracking aromatization heavy oil fraction is returned to step (1) for reprocessing.

[0014] (3) The above-mentioned cracked aromatized light gasoline fraction is mixed with methanol and then fed into the light gasoline etherification unit to carry out the light gasoline etherification reaction to obtain the etherified light gasoline fraction.

[0015] (4) The cracked aromatization gas product obtained in step (2) is optionally mixed with Fischer-Tropsch synthesis liquefied gas and then sent to a gas separation unit for gas separation to obtain dry gas, propylene, propane and C4 components.

[0016] (5) The above C4 component is mixed with methanol and then fed into the C4 etherification unit for C4 etherification reaction to obtain the etherified C4 component and methyl tert-butyl ether.

[0017] (6) The above-mentioned C4 component after etherification is mixed with a portion of the propylene obtained in step (4) and then fed into the alkylation unit for alkylation reaction to obtain alkylated gasoline fraction and n-butane; wherein, the n-butane is fed into the n-butane isomerization unit for isomerization reaction to obtain isobutane, and the isobutane is recycled back to the above-mentioned alkylation unit for reprocessing.

[0018] (7) The dry gas and part of the propane described in step (4) are fed into the auxiliary fuel chamber as fuel gas to heat the cracking aromatization reaction unit described in step (1).

[0019] (8) Recycle another portion of the propylene obtained in step (4) back to the cracking aromatization reaction unit in step (1);

[0020] (9) By blending the cracked aromatic heavy gasoline fraction, the etherified light gasoline fraction, the methyl tert-butyl ether and the alkylated gasoline fraction, an ultra-clean gasoline product is obtained.

[0021] In another aspect, the present invention provides an apparatus for implementing the method described above, wherein the apparatus comprises the following units:

[0022] Cracking and aromatization reaction unit;

[0023] An oil and gas fractionation unit, the inlet of which is fluidly connected to the upper outlet of the cracking aromatization reaction unit, and the lower outlet of which is fluidly connected to the cracking aromatization heavy oil inlet of the cracking aromatization reaction unit.

[0024] A gas separation unit, the inlet of which is fluidly connected to the cracking aromatization gas product outlet of the oil and gas fractionation unit;

[0025] A light gasoline etherification unit, wherein the inlet of the light gasoline etherification unit is fluidly connected to the outlet of the cracked aromatized light gasoline fraction of the oil and gas fractionation unit;

[0026] The lower outlet of the gas separation unit is connected to the inlet of the C4 etherification unit in a fluid communication manner.

[0027] An alkylation unit, the inlet of which is fluidly connected to the outlet of the etherified C4 component of the C4 etherification unit and the propylene outlet of the gas separation unit;

[0028] The n-butane isomerization unit has its inlet connected in fluid communication to the n-butane outlet of the alkylation unit, and its outlet connected in fluid communication to the inlet of the alkylation unit.

[0029] The gasoline tank is connected in fluid communication with the oil and gas fractionation unit, the light gasoline etherification unit, the C4 etherification unit, and the alkylation unit.

[0030] The technical solution provided by this invention has the following beneficial effects:

[0031] (1) The method of the present invention can be used to convert full-fraction Fischer-Tropsch synthesis intermediates into clean gasoline that meets the China VI standard.

[0032] (2) The integrated gasoline octane number obtained by processing the Fischer-Tropsch synthesis intermediates using the method of the present invention in a single-pass conversion is greater than 95, and the total gasoline yield can reach more than 83%.

[0033] (3) Compared with conventional petroleum-based commercial gasoline, gasoline obtained by processing Fischer-Tropsch synthesis intermediates using the method of the present invention has a lower sulfur content (less than 1.8 ppm), a higher aromatic content and a higher oxygen content. When the engine bench test is conducted, the amount of exhaust pollutants produced by combustion is lower, showing superior clean performance.

[0034] Other features and advantages of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0035] The accompanying drawings are part of the specification and, together with the detailed description, provide a further explanation of the invention, but are not intended to limit the invention.

[0036] Figure 1This is a schematic flowchart of a method for generating ultra-clean gasoline by coupling Fischer-Tropsch synthesis oil with methanol, provided by the present invention.

[0037] The following are explanations of the reference numerals in the attached figures: 1, Fischer-Tropsch synthesis feedstock; 2, methanol feedstock; 3, cracking aromatization product; 4, Fischer-Tropsch synthesis liquefied petroleum gas feedstock; 5, cracking aromatization gas product; 6, cracking aromatization light gasoline fraction; 7, cracking aromatization heavy gasoline fraction; 8, cracking aromatization diesel fraction; 9, cracking aromatization heavy oil; 10, dry gas; 11, propylene; 12, propane; 13, C4 component; 14, etherified C4 component; 15, methyl tert-butyl ether; 16, etherified light gasoline fraction; 17, isobutane; 18, n-butane; 19, alkylated gasoline fraction.

[0038] A, First cracking aromatization reaction unit reactor; B, Second cracking aromatization reaction unit reactor; C, Auxiliary combustion chamber; D, Regenerator; E, Oil and gas fractionation unit; F, Light gasoline etherification unit; G, Gas separation unit; H, C4 etherification unit; I, Alkylation unit; J, n-Butane isomerization unit; K, Gasoline pool. Detailed Implementation

[0039] The specific embodiments of the present invention will be described in detail below. The specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of the invention.

[0040] In one embodiment, the present invention relates to a method for producing ultra-clean gasoline by coupling Fischer-Tropsch synthetic oils with methanol, wherein the method includes the following steps:

[0041] (1) Fischer-Tropsch synthetic oil is preheated, atomized and then mixed with methanol and fed into the cracking aromatization reaction unit to carry out the cracking aromatization reaction to obtain cracking aromatization products;

[0042] (2) The above-mentioned cracking aromatization products are fed into the oil and gas fractionation unit for oil and gas fractionation to obtain cracking aromatization gas products, cracking aromatization light gasoline fraction, cracking aromatization heavy gasoline fraction, cracking aromatization diesel fraction and cracking aromatization heavy oil fraction, wherein the cracking aromatization heavy oil fraction is returned to step (1) for reprocessing.

[0043] (3) The above-mentioned cracked aromatized light gasoline fraction is mixed with methanol and then fed into the light gasoline etherification unit to carry out the light gasoline etherification reaction to obtain the etherified light gasoline fraction.

[0044] (4) The cracked aromatization gas product obtained in step (2) is optionally mixed with Fischer-Tropsch synthesis liquefied gas and then sent to a gas separation unit for gas separation to obtain dry gas, propylene, propane and C4 components.

[0045] (5) The above C4 component is mixed with methanol and then fed into the C4 etherification unit for C4 etherification reaction to obtain the etherified C4 component and methyl tert-butyl ether.

[0046] (6) The above-mentioned C4 component after etherification is mixed with a portion of the propylene obtained in step (4) and then fed into the alkylation unit for alkylation reaction to obtain alkylated gasoline fraction and n-butane; wherein, the n-butane is fed into the n-butane isomerization unit for isomerization reaction to obtain isobutane, and the isobutane is recycled back to the above-mentioned alkylation unit for reprocessing.

[0047] (7) The dry gas and part of the propane described in step (4) are fed into the auxiliary fuel chamber as fuel gas to heat the cracking aromatization reaction unit described in step (1).

[0048] (8) Recycle another portion of the propylene obtained in step (4) back to the cracking aromatization reaction unit in step (1);

[0049] (9) By blending the cracked aromatic heavy gasoline fraction, the etherified light gasoline fraction, the methyl tert-butyl ether and the alkylated gasoline fraction, an ultra-clean gasoline product is obtained.

[0050] The Fischer-Tropsch synthetic oils described in this invention are derived from Fischer-Tropsch wax, Fischer-Tropsch heavy oil, Fischer-Tropsch light oil, Fischer-Tropsch naphtha, etc., produced by Fischer-Tropsch synthesis technology from syngas generated by the gasification of carbon-containing resources such as coal, natural gas, and biomass, or mixtures thereof in any proportion.

[0051] The Fischer-Tropsch synthetic oil products described in this invention can also be fed together with Fischer-Tropsch liquefied gas and organic oxygen-containing compounds produced as byproducts of the Fischer-Tropsch synthesis process.

[0052] In a preferred embodiment, in step (1), the preheating temperature of the Fischer-Tropsch synthetic oil is 100-350°C, preferably 150-300°C, for example 200-270°C or 250-270°C.

[0053] In a preferred embodiment, in step (1), the weight ratio of the Fischer-Tropsch synthetic oil to methanol is (0.05-0.5):1, preferably (0.15-0.45):1, for example (0.2-0.3):1 or (0.3-0.4):1.

[0054] In a preferred embodiment, in step (1), the reaction conditions for the cracking aromatization reaction are: temperature 350-500℃ (preferably 350-450℃, for example 375-450℃ or 400℃-420℃), pressure 0.01-1.00MPa (preferably 0.1-0.7MPa, for example 0.2-0.4MPa or 0.3-0.8MPa), and weight hourly space velocity 0.5-40h. -1 (Preferred 1-30h)-1 For example, 1-20h -1 or 1-8h -1 The agent-to-oil ratio is 2.0-10.0 (preferably 2.0-8.0, for example 6.0-8.0).

[0055] In a preferred embodiment, in step (1), the cracking aromatization reaction is carried out in the presence of a cracking aromatization catalyst, the main active component of which is a ten-membered ring channel molecular sieve. Based on the total dry weight of the catalyst, the dry weight content of the ten-membered ring channel molecular sieve is 10-60 m% (preferably 20-50 m%, for example 35-50 m%). The ten-membered ring channel molecular sieve includes at least one of H-type or elementally modified ZSM-5, ZSM-11, ZSM-22, ZSM-35, MCM-22 and other molecular sieves (preferably one or more of ZSM-5, ZSM-11, ZSM-22 and ZSM-35 molecular sieves modified by any one of P, Zn, Ag, LaZn and rare earth metals).

[0056] In this invention, the fractionation described in step (2) is a conventional technique in the art.

[0057] In a preferred embodiment, in step (3), the reaction conditions for the light gasoline etherification reaction are as follows: the cracked aromatized light gasoline fraction is mixed with methanol, pre-etherified through one or more fixed-bed reactions, and then deeply etherified in the presence of an etherification catalyst in a catalytic distillation column. The product at the top of the column is washed with water to remove methanol and then mixed with the etherified product at the bottom of the column to obtain the etherified light gasoline fraction.

[0058] In this invention, the cracked aromatized light gasoline fraction is a gasoline fraction with a temperature of less than 90°C (preferably a gasoline fraction with a temperature of less than 75°C).

[0059] In a preferred embodiment, in step (3), the pre-etherification reaction conditions are: reaction temperature 30-100℃ (preferably 40-80℃, for example 50-55℃, 55-60℃ or 60-80℃); reaction pressure 0.5-2MPa (preferably 0.8-1.5MPa, for example 0.5-1.0MPa or 1.0-1.5MPa); and liquid hourly space velocity (LHSV) of 0.5-5.0 h⁻¹. -1 (Preferred 1.0-4.0h) -1 For example, 1.0-3.0h -1 Or 2.0-3.0h -1 The oil-to-ethanol ratio (v / v) is 5-15 (preferably 8-13, such as 7-12, 12-13 or 10-13).

[0060] In a preferred embodiment, in step (3), the conditions of the catalytic distillation column are: the top temperature of the column is 35-70℃ (preferably 38-65℃, for example 40-65℃ or 38-50℃), and the bottom temperature of the column is 100-160℃ (preferably 110-155℃, for example 110-150℃ or 125-130℃); the etherification catalyst can be a general light gasoline etherification catalyst, preferably, the catalyst is an acidic catalyst, preferably including one or more of molecular sieves, heteropoly acids, and resin catalysts, more preferably a sulfonic acid type strong acid cation exchange resin catalyst.

[0061] In a preferred embodiment, in step (3), before mixing with methanol, the etherification process described in the above steps may also include selective hydrodeolefination of light gasoline on a precious metal catalyst, which is common in the field of light gasoline etherification.

[0062] Preferably, in step (3), before mixing with methanol, the light gasoline etherification reaction further includes subjecting the cracked aromatized light gasoline to a selective hydrogenation dediolefin reaction, wherein the selective hydrogenation dediolefin conditions are: supported catalyst, reaction temperature 70-120℃ (preferably 80-100℃, for example 90-100℃), pressure 0.5-2.0MPa (preferably 0.8-1.5MPa, for example 1.0-1.5MPa), hydrogen-to-oil volume ratio 20-40 (preferably 25-35, for example 25-30), and space velocity 2-36h. -1 (Preferred 10-30h) -1 For example, 20-30h -1 Preferably, the supported catalyst includes a noble metal catalyst with one or more noble metals selected from Pt and Pd as the active component and / or a catalyst with one or more non-noble metals selected from Mo, W, Co, Ni, and Al as the active component, preferably Ni-Mo / Al2O3.

[0063] In this invention, the gas separation described in step (4) is a conventional technique in the art.

[0064] In a preferred embodiment, in step (5), the C4 etherification reaction includes a pre-etherification reaction and a catalytic distillation deep etherification reaction. The reaction conditions for the pre-etherification reaction are: reaction temperature 30-70℃ (preferably 40-65℃, for example 40-60℃ or 50-60℃); reaction pressure 0-1.5MPa (preferably 0.3-1.0MPa, for example 0.3-0.8MPa or 0.4-0.8MPa); liquid hourly space velocity (LHSV) 0.5-5.0 h⁻¹. -1 (Preferred 1.0-3.0h) -1 For example, 1.2-2.5h -1 Or 2.5-3.0h -1The molar ratio of alcohol to olefin is 0.9-1.5 (preferably 1.0-1.2, for example 1.1-1.2). The catalytic distillation column conditions for the deep etherification reaction are as follows: bed temperature 35-70℃ (preferably 40-65℃, for example 40-60℃), reaction pressure 0-1.5MPa (preferably 0.3-0.8MPa), column top temperature 40-60℃, and column bottom temperature 100-140℃ (preferably 110-135℃, for example 110-125℃ or 110-120℃).

[0065] In a preferred embodiment, in step (5), the C4 etherification unit may further include a C4 selective hydrogenation dediolefination unit, wherein the C4 selective hydrogenation dediolefination conditions are: temperature on the supported catalyst 70-120℃ (preferably 75-100℃, for example 80-100℃), pressure 0.5-2.0MPa (preferably 0.8-1.7MPa, for example 1.5-1.7MPa), hydrogen-to-oil volume ratio 20-40 (preferably 30-40), and space velocity 2-36h. -1 (Preferred 2-20h) -1 Preferably, the supported catalyst includes a noble metal catalyst with one or more noble metals selected from Pt and Pd as the active component and / or a catalyst with one or more non-noble metals selected from Mo, W, Co, Ni, and Al as the active component, preferably Ni-Mo / Al2O3.

[0066] In a preferred embodiment, in step (6), the alkylation reaction is a sulfuric acid alkylation reaction, and the reaction conditions are: reaction temperature -10 to 30°C (preferably -5 to 15°C, for example -1 to 10°C, 5 to 10°C or 0 to 8°C), alkyl-olefin ratio (6 to 12):1 (preferably (7 to 10):1, for example (8 to 10):1).

[0067] In a preferred embodiment, the propylene in step (6) accounts for 50-100% of the total propylene in step (4), for example, 50-70%, 50-75%, or 70-90%.

[0068] In a preferred embodiment, in step (6), the reaction conditions for the isomerization reaction are: reaction temperature 210-230℃ (preferably 215-225℃, for example 220℃-225℃), pressure 1.5-2.2MPa (preferably 1.6-2.2MPa, for example 1.8-2.2MPa, 2.0-2.2MPa), and space velocity 1.0-2.2h. -1 (Preferred 1.8-2.2h) -1 For example, 2.0-2.2h -1 The hydrogen-to-hydrogen ratio is 1.0-2.0 (preferably 1.2-1.5, for example 1.2-1.3).

[0069] In a preferred embodiment, the propane in step (7) accounts for 0-50% of the total propane in step (4).

[0070] In a preferred embodiment, the method includes the following steps:

[0071] (1) The Fischer-Tropsch synthetic oil is preheated to 100-350℃, atomized, and then mixed with methanol at a weight ratio of (0.05-0.5):1. The mixture is then introduced into the cracking aromatization reaction unit at a temperature of 350-500℃, a pressure of 0.01-1.00 MPa, and a weight hourly space velocity of 0.5-40 h⁻¹. -1 The cracking aromatization reaction was carried out under the condition of an oil-to-crack ratio of 2.0-10.0 to obtain the cracking aromatization product;

[0072] (2) The above-mentioned cracking aromatization products are fed into the oil and gas fractionation unit for oil and gas fractionation to obtain cracking aromatization gas products, cracking aromatization light gasoline fraction, cracking aromatization heavy gasoline fraction, cracking aromatization diesel fraction and cracking aromatization heavy oil fraction, wherein the cracking aromatization heavy oil fraction is returned to step (1) for reprocessing.

[0073] (3) The cracked aromatized light gasoline fraction is selectively hydrogenated to remove dienes and then mixed with methanol. The reaction is carried out at a temperature of 30-100℃, a pressure of 0.5-2MPa, and a liquid hourly space velocity of 0.5-5.0h. -1 Pre-etherification is carried out under conditions of an oil-to-methanol ratio (v / v) of 5-15, followed by deep etherification in a catalytic distillation column at a top temperature of 35-70℃ and a bottom temperature of 100-160℃ in the presence of a sulfonic acid-type strong acid cation exchange resin catalyst to obtain etherified light gasoline fraction; the selective hydrode-diolefin conditions are: supported catalyst Ni-Mo / Al2O3, reaction temperature 70-120℃, pressure 0.5-2.0MPa, hydrogen-to-oil volume ratio 20-40, and space velocity 2-36h. -1 ;

[0074] (4) The cracked aromatization gas product obtained in step (2) is optionally mixed with Fischer-Tropsch synthesis liquefied gas and then sent to a gas separation unit for gas separation to obtain dry gas, propylene, propane and C4 components.

[0075] (5) The above C4 component was tested under the following conditions: catalyst Ni-Mo / Al2O3, temperature 70-120℃, pressure 0.5-2.0MPa, hydrogen-to-oil volume ratio 20-40, and space velocity 2-36h. -1 Under specific conditions, the product undergoes selective hydrogenation of the diene, is mixed with methanol, and then fed into a C4 etherification unit. The reaction proceeds at a temperature of 30-70°C, a pressure of 0-1.5 MPa, and a liquid hourly space velocity of 0.5-5.0 h⁻¹. -1The pre-etherification reaction was carried out under the condition of an alcohol-olefin molar ratio of 0.9-1.5. The pre-etherification product was fed into a catalytic distillation column and carried out a deep etherification reaction under the conditions of bed temperature of 35-70℃, reaction pressure of 0-1.5MPa, column top temperature of 40-60℃, and column bottom temperature of 100-140℃ to obtain the etherified C4 component and methyl tert-butyl ether.

[0076] (6) The above-mentioned C4 component after etherification is mixed with a portion of the propylene obtained in step (4) and then fed into an alkylation unit for alkylation reaction at a reaction temperature of -10 to 30°C and an alkyl-to-olefin ratio of (6 to 12):1 to obtain alkylated gasoline fraction and n-butane; wherein, the n-butane is introduced into a n-butane isomerization unit at a reaction temperature of 210-230°C, a pressure of 1.5-2.2 MPa, and a space velocity of 1.0-2.2 h⁻¹. -1 The isomerization reaction is carried out under conditions of hydrogen-to-hydrogen ratio of 1.0-2.0 to obtain isobutane, and the isobutane is recycled back to the above-mentioned alkylation unit for reprocessing;

[0077] (7) The dry gas and part of the propane described in step (4) are sent as fuel gas into the auxiliary fuel chamber to heat the regeneration system of the cracking aromatization reaction unit.

[0078] (8) Recycle another portion of the propylene obtained in step (4) back to the cracking aromatization reaction unit in step (1);

[0079] (9) By blending the cracked aromatic heavy gasoline fraction, the etherified light gasoline fraction, the methyl tert-butyl ether and the alkylated gasoline fraction, an ultra-clean gasoline product is obtained.

[0080] In another embodiment, the present invention provides an apparatus for implementing the method described above, wherein the apparatus comprises the following units:

[0081] A cracking aromatization reaction unit, optionally equipped with a catalyst regenerator and an auxiliary combustion chamber;

[0082] An oil and gas fractionation unit, the inlet of which is fluidly connected to the upper outlet of the cracking aromatization reaction unit, and the lower outlet of which is fluidly connected to the cracking aromatization heavy oil inlet of the cracking aromatization reaction unit.

[0083] A gas separation unit, the inlet of which is fluidly connected to the cracking aromatization gas product outlet of the oil and gas fractionation unit;

[0084] A light gasoline etherification unit, wherein the inlet of the light gasoline etherification unit is fluidly connected to the outlet of the cracked aromatized light gasoline fraction of the oil and gas fractionation unit;

[0085] The lower outlet of the gas separation unit is connected to the inlet of the C4 etherification unit in a fluid communication manner.

[0086] An alkylation unit, the inlet of which is fluidly connected to the outlet of the etherified C4 component of the C4 etherification unit and the propylene outlet of the gas separation unit;

[0087] The n-butane isomerization unit has its inlet connected in fluid communication to the n-butane outlet of the alkylation unit, and its outlet connected in fluid communication to the inlet of the alkylation unit.

[0088] The gasoline tank is connected in fluid communication with the oil and gas fractionation unit, the light gasoline etherification unit, the C4 etherification unit, and the alkylation unit.

[0089] In a preferred embodiment, the cracking aromatization reaction unit is optionally equipped with a catalyst regenerator and an auxiliary combustion chamber.

[0090] In a preferred embodiment, the cracking aromatization reaction unit includes a first cracking aromatization reaction unit and a second cracking aromatization reaction unit. The first cracking aromatization reaction unit is used to process the atomized Fischer-Tropsch synthetic oil and methanol into the cracking aromatization reaction. The second cracking aromatization reaction unit is used to reprocess the cracked aromatized heavy oil produced by the oil and gas fractionation unit and then further feed it into the first cracking aromatization reaction unit.

[0091] The following combination Figure 1 The present invention will be further described below.

[0092] like Figure 1 As shown, Fischer-Tropsch synthetic oil feed 1, preheated to a suitable temperature, and methanol 2, with a weight ratio of 0.05–0.5 to the Fischer-Tropsch synthetic oil, first enter the cracking aromatization unit reactor A, at a temperature of 350–550 °C and a weight hourly space velocity of 0.5–200 h⁻¹. -1 Under pressures of 0.01-1.00 MPa, cracking aromatization product 3 is obtained. Cracking aromatization product 3 is separated in oil-gas fractionation unit E to obtain cracking aromatization gaseous product 5 (i.e., rich gas product), cracking aromatization light gasoline fraction 6 (i.e., light gasoline fraction), cracking aromatization heavy gasoline fraction 7 (i.e., heavy gasoline fraction), cracking aromatization diesel fraction 8 (i.e., diesel fraction), and cracking aromatization heavy oil 9 (i.e., heavy oil fraction as slurry). Cracking aromatization gaseous product 5 and Fischer-Tropsch liquefied petroleum gas 4 are then separated in gas separation unit G to obtain dry gas 10, propylene 11, propane 12, and C4 component 13.

[0093] After being mixed with methanol 2, the cracked aromatized light gasoline 6 is introduced into the light gasoline etherification unit F, and the mixture is heated at a temperature of 30–100°C and a heavy hourly space velocity of 0.5–5 h⁻¹. -1 Pre-etherification was carried out under conditions of pressure 0.5-2 MPa and oil-to-ethanol ratio (V / V) 5-15. The pre-etherified product was then subjected to deep etherification by catalytic distillation to obtain etherified light gasoline 16.

[0094] After C4 component 13 is mixed with methanol 2, it enters the C4 etherification unit H, and the reaction is carried out at a temperature of 30-100℃, a pressure of 0-1.5MPa, and a liquid hourly space velocity of 0.5-5.0h. -1 The etherification reaction was completed under conditions where the alcohol-to-olefin molar ratio was 0.9-1.5, yielding methyl tert-butyl ether 15 and etherified C4 component 14.

[0095] After etherification, the C4 component and a portion of propylene are mixed and then enter alkylation unit I. Alkylation reaction is carried out at a reaction temperature of -10 to 30°C and an alkyl-to-olefin ratio of (6 to 12):1 to obtain alkylated gasoline 19 and n-butane 18. n-Butane 18 enters isomerization unit J and undergoes isomerization reaction to generate isobutane 17. Isobutane 17 is returned to alkylation unit I to generate alkylated gasoline fraction 19.

[0096] The cracked aromatized heavy gasoline fraction 7, the etherified light gasoline fraction 16, the methyl tert-butyl ether 15, and the alkylated gasoline fraction 19 are mixed and blended in gasoline pool K to obtain the final gasoline product; dry gas 10 can be used as fuel gas in the auxiliary combustion chamber C of the cracked aromatization unit; another portion of propylene 11 can be recycled into reactor A; propane 12 exits the unit as liquefied petroleum gas; and cracked aromatized slurry oil 9 can be recycled into reactor B.

[0097] Methanol conversion is a rapid and strongly exothermic reaction with a heat of reaction of approximately 1740 kJ / kg and an adiabatic temperature rise of up to 600°C. The Fischer-Tropsch heavy hydrocarbon catalytic cracking aromatization conversion process involves multiple reactions such as cracking, cyclization, and hydrogen transfer. The heat of reaction of Fischer-Tropsch wax reaches -864 kJ / kg, making it a strongly endothermic reaction process. The reaction requires a large amount of high-temperature heat carrier (catalyst) circulation. Coupled with the strongly endothermic Fischer-Tropsch heavy hydrocarbon conversion reaction and the strongly exothermic methanol conversion, heat complementarity can be achieved, improving technical and economic efficiency.

[0098] Fischer-Tropsch heavy hydrocarbon catalytic conversion follows the conventional C20-C20 model. + Mechanism, C + Formation is the main step, and the methanol-to-hydrocarbon conversion process is generally considered to follow the "hydrocarbon pool mechanism" proposed by Dahl and Kolboe et al., where Fischer-Tropsch heavy hydrocarbons are coupled with in-situ methanol conversion. For methanol conversion, it will be caused by C +The introduction of olefins into the hydrocarbon pool species through the mechanism shortens the methanol conversion induction period. For Fischer-Tropsch heavy hydrocarbon conversion, the introduction of methanol is conducive to C+ formation. Methanol molecules are first adsorbed on the Brønsted acid sites of the molecular sieve, thereby forming methoxy groups. The methoxy groups and alkanes adsorbed on the catalyst form carbocation structures, which in turn accelerates the formation of olefins and enriches the hydrocarbon pool species. The two promote each other, which can improve the feed conversion rate and change the product properties.

[0099] The present invention is further illustrated below by way of examples, but the present invention is not limited thereto.

[0100] Example

[0101] Unless otherwise stated, the reagents, materials and apparatus involved in the following examples are all commercially available in the art; the routine operations involved in the following examples can be found in patents, patent applications and publications disclosed in the art (e.g., He Yongde, ed., Modern Coal Chemical Technology Handbook, Chemical Industry Press, 2003, but not limited thereto).

[0102] In the following examples, the relevant properties of Fischer-Tropsch synthetic oils are shown in Table 1.

[0103] Table 1. Physicochemical properties of typical Fischer-Tropsch synthetic oil feedstocks

[0104] Basic properties Fischer-Tropsch synthetic wax Fischer-Tropsch Synthetic Heavy Oil Fischer-Tropsch Synthetic Light Oil <![CDATA[Density (20 °C), kg / m 3 > 866 812 720 Pour point, ℃ 92 22 -18 C, w% 84.94 84.90 84.80 H, w% 14.86 14.77 14.67 O,w% 0.20 0.33 0.52 Distillation range, °C IBP 380 265 37.8 10％ 425 281 84.7 50％ 643 354 180.5 90％ 720(79％*) 431 294.8 FBP / ** 458 327.4

[0105] Note: * indicates the upper limit of chromatographic detection, 79% distillation at 720℃; / ** indicates exceeding the upper limit of detection.

[0106] Example 1

[0107] This embodiment uses Fischer-Tropsch synthesis wax and methanol as raw materials, and selects Cat-1 as the catalyst, which is a mixed molecular sieve of Zn-modified ZSM-5 and P-modified ZSM-35 as the active component, with a dry basis content of 35% in the catalyst. First, the Fischer-Tropsch synthesis wax is preheated to 270°C, then atomized with methanol before entering the methanol-fueled mixture. Figure 1 In the fluidized bed reactor A shown, the weight ratio of Fischer-Tropsch synthesis wax to methanol is 0.5, the reactor temperature is 400℃, and the weight hourly space velocity is 8 h⁻¹. -1The cracking aromatization reaction takes place at a reaction pressure of 0.20 MPa and a catalyst-to-feed ratio (fresh catalyst to feedstock ratio) of 6.0, yielding reaction intermediates. These intermediates rise into a settling tank, where a cyclone separator at the top removes any remaining catalyst. The final product then enters a fractionation system to separate cracking aromatization gas products, cracking aromatization light gasoline fraction, cracking aromatization heavy gasoline fraction, cracking aromatization diesel fraction, and cracking aromatization heavy oil. The deactivated catalyst moves downwards with the bed and enters the stripping section. After steam stripping, it is fed through a regenerator via a regenerator incised tube to a coke burner and regenerator for coke regeneration. The resulting regenerated catalyst is then recycled into the fluidized bed reactor via a regeneration incised tube.

[0108] Cracking and aromatizing of light gasoline at 100℃, 1.5MPa, hydrogen-to-oil ratio (V / V) 25, and space velocity 30h⁻¹ -1 After selective hydrogenation of dienes via Ni-Mo / Al2O3 catalyst, the mixture is combined with methanol and then fed into a light gasoline etherification unit at 60°C and a weight hourly space velocity (WHSV) of 1 h⁻¹. -1 Pre-etherification was completed under the conditions of pressure 2MPa and oil-to-methanol ratio (V / V) 10. The pre-etherified product entered a catalytic distillation column, and after deep etherification by sulfonic acid-type strong acid cation exchange resin catalyst at a column top temperature of 38℃ and a column bottom temperature of 125℃, etherified light gasoline fraction 16 was obtained.

[0109] The rich product 5 from cracking aromatization and Fischer-Tropsch synthesis liquefied gas 4 are separated together in gas separation unit G to produce dry gas 10, propylene 11, propane 12, and a mixed C4 component 13. The mixed C4 component 13 is then subjected to a reaction at 100°C, 2.0 MPa, a hydrogen-to-oil ratio (V / V) of 30, and a space velocity of 20 h⁻¹. -1 After selective hydrogenation of the diene via Ni-Mo / Al₂O₃ catalyst, it is mixed with methanol 2 and then introduced into the C₄ etherification unit H. The reaction is carried out at a temperature of 45°C, a pressure of 0.5 MPa, and a liquid hourly space velocity of 2.5 h⁻¹. -1 The pre-etherification reaction was completed under the condition that the alcohol-to-olefin molar ratio was 1.0. The pre-etherified product entered a catalytic distillation column and under the conditions of column top temperature 40℃, column bottom temperature 110℃, bed temperature 55℃ and pressure 0.5MPa, it was deeply etherified by catalytic distillation to obtain methyl tert-butyl ether and etherified C4 component 14.

[0110] The C4 component after etherification, along with propylene comprising 50% of the total propylene content of propylene 11, is then introduced into alkylation unit I. Alkylation is carried out under concentrated sulfuric acid conditions at a reaction temperature of 0°C and an alkyl-to-olefin ratio of 8:1 to yield alkylated gasoline and n-butane. n-Butane 18 then enters isomerization unit J, where it undergoes alkylation at 210°C, a pressure of 1.6 MPa, and a space velocity of 1.5 h⁻¹. -1 Under conditions where the hydrogen / hydrocarbon ratio is 1.2, an isomerization reaction occurs to produce isobutane, which is then returned to alkylation unit I to regenerate alkylated gasoline.

[0111] The cracked aromatized heavy gasoline fraction, etherified light gasoline fraction, methyl tert-butyl ether, and alkylated gasoline fraction are mixed and blended in gasoline pool K to obtain the final gasoline product; dry gas 10 can be used as fuel gas in the auxiliary combustion chamber C of the cracked aromatization unit; propane 12 exits the unit as liquefied petroleum gas; and cracked aromatized slurry 9 can enter reactor B for reprocessing.

[0112] The yields, composition, and RON octane numbers of gasoline products obtained by mixing cracked aromatized heavy gasoline fraction, etherified light gasoline fraction, methyl tert-butyl ether, and alkylated gasoline fraction are shown in Table 2.

[0113] Example 2

[0114] This embodiment uses a mixture of Fischer-Tropsch synthetic wax and Fischer-Tropsch synthetic heavy oil in a weight ratio of 3:1 and methanol as raw materials. Cat-2 catalyst, with Ag-modified ZSM-5 and P-modified MCM-22 mixed molecular sieves as active components, is selected as the catalyst. The dry basis content of the molecular sieve in the catalyst is 48%. The ratio of the Fischer-Tropsch synthetic wax and heavy oil mixture to methanol is 0.3. The Fischer-Tropsch synthetic wax and heavy oil mixture is first preheated to 250°C, then atomized with methanol before entering the methanol-methanol mixture. Figure 1 In the fluidized bed reactor A shown, the reactor temperature is 420℃ and the weight hourly space velocity is 20.0 h⁻¹. -1 The reaction occurs at a pressure of 0.8 MPa and a catalyst-to-oil ratio of 8.0, yielding intermediate products. These intermediate products rise into a settling tank, where a cyclone separator at the top removes any remaining catalyst. The final product then enters a fractionation system to separate the cracked aromatized gaseous products, cracked aromatized light gasoline fraction, cracked aromatized heavy gasoline fraction, cracked aromatized diesel fraction, and cracked aromatized heavy oil. The deactivated catalyst moves downwards with the bed and enters the stripping section. After steam stripping, it is fed through a regenerated inclined tube into a coke burner and regenerator for coke regeneration. The resulting regenerated catalyst is then recycled into the fluidized bed reactor via a regeneration inclined tube.

[0115] Cracked aromatized light gasoline was subjected to an oxidation process at 80°C, 0.8 MPa, hydrogen-to-oil ratio (V / V) 30, and space velocity 10 h⁻¹. -1 After selective hydrogenation of dienes using Ni-Mo / Al₂O₃ catalyst, the mixture is combined with methanol and then fed into a light gasoline etherification unit at 55°C and a weight hourly space velocity (WHSV) of 0.5 h⁻¹. -1 Pre-etherification was completed under the conditions of pressure 0.5 MPa and oil-to-ethanol ratio (V / V) 13. The pre-etherified product entered a catalytic distillation column and was deeply etherified by distillation with a sulfonic acid-type strong acid cation exchange resin catalyst at a column top temperature of 40°C and a column bottom temperature of 130°C to obtain etherified light gasoline 16.

[0116] The rich product 5 from cracking aromatization and Fischer-Tropsch synthesis liquefied petroleum gas (LPG) 4 were separated together in gas separation unit G to produce dry gas 10, propylene 11, propane 12, and a mixed C4 component 13. The mixed C4 component 13 was then separated at 80°C, 1.7 MPa, a light-to-oil ratio (V / V) of 20, and a space velocity of 20 h⁻¹. -1 After selective hydrogenation of the diene via Ni-Mo / Al₂O₃ catalyst, it is mixed with methanol 2 and then introduced into the C₄ etherification unit H. The reaction is carried out at a temperature of 40°C, a pressure of 0.2 MPa, and a liquid hourly space velocity of 4 h⁻¹. -1 The pre-etherification reaction was completed under the condition that the alcohol-olefin molar ratio was 1.2. The pre-etherified product entered a catalytic distillation column and under the conditions of column top temperature 43℃, column bottom temperature 120℃, bed temperature 60℃ and pressure 0.8MPa, it was deeply etherified by catalytic distillation to obtain methyl tert-butyl ether and etherified C4 component 14.

[0117] The C4 component after etherification, along with propylene comprising 70% of the total propylene content of propylene 11, is then introduced into alkylation unit I. Alkylation is carried out under concentrated sulfuric acid conditions at a reaction temperature of -5°C and an alkyl-to-olefin ratio of 10:1 to yield alkylated gasoline and n-butane. n-Butane 18 then enters isomerization unit J, where it undergoes alkylation at 220°C, a pressure of 1.8 MPa, and a space velocity of 1.0 h⁻¹. -1 Under conditions where the hydrogen / hydrocarbon ratio is 2, an isomerization reaction occurs to produce isobutane, which is then returned to alkylation unit I to regenerate alkylated gasoline.

[0118] The cracked aromatized heavy gasoline fraction, etherified light gasoline fraction, methyl tert-butyl ether, and alkylated gasoline fraction are mixed and blended in gasoline pool K to obtain the final gasoline product; dry gas 10 can be used as fuel gas in the auxiliary combustion chamber C of the cracked aromatization unit; propane 12 exits the unit as liquefied petroleum gas; and cracked aromatized slurry 9 can enter reactor B for reprocessing.

[0119] The yields, composition, and RON octane numbers of gasoline products obtained by mixing cracked aromatized heavy gasoline fraction, etherified light gasoline fraction, methyl tert-butyl ether, and alkylated gasoline fraction are shown in Table 2.

[0120] Example 3

[0121] This embodiment uses a mixture of Fischer-Tropsch synthetic wax, Fischer-Tropsch heavy oil, and Fischer-Tropsch light oil in a weight ratio of 3:1:2, and methanol as raw materials. Cat-3 catalyst, with a mixed molecular sieve of P-modified ZSM-5 and Zn-modified ZSM-22 as the active component, is selected as the catalyst. The dry basis content of the molecular sieve in the catalyst is 35%. The weight ratio of Fischer-Tropsch synthetic wax, Fischer-Tropsch heavy oil, and Fischer-Tropsch light oil to methanol is 0.08. First, the mixture of Fischer-Tropsch synthetic wax and heavy oil is preheated to 150°C, then atomized with methanol before entering the methanol-methanol mixture. Figure 1 In the fluidized bed reactor A shown, the reactor temperature is 375℃ and the weight hourly space velocity is 1h. -1The reaction occurs at a pressure of 0.40 MPa and a catalyst-to-oil ratio of 2, yielding intermediate products. These intermediate products rise into a settling tank, where a cyclone separator at the top removes any remaining catalyst. The final product then enters a fractionation system, where it is fractionated to produce cracked aromatized gaseous products, cracked aromatized light gasoline fraction, cracked aromatized heavy gasoline fraction, cracked aromatized diesel fraction, and cracked aromatized heavy oil. The deactivated catalyst moves downwards with the bed and enters the stripping section. After steam stripping, it is fed through a regenerated inclined tube into a coke burner and regenerator for coke regeneration. The resulting regenerated catalyst is then recycled into the fluidized bed reactor via a regeneration inclined tube.

[0122] Cracking and aromatizing of light gasoline was carried out at 100°C, 1.5 MPa, hydrogen-to-oil ratio (V / V) 40, and space velocity 20 h⁻¹. -1 After selective hydrogenation of dienes using Ni-Mo / Al2O3 catalyst, the mixture is combined with methanol and then fed into a light gasoline etherification unit at 50°C and a weight hourly space velocity (WHSV) of 4 h⁻¹. -1 Pre-etherification was completed under conditions of 1 MPa pressure and an oil-to-methanol ratio (V / V) of 7. The pre-etherified product entered a catalytic distillation column and was deeply etherified by a sulfonic acid-type strong acid cation exchange resin catalyst at a column top temperature of 65°C and a column bottom temperature of 155°C to obtain etherified light gasoline 16.

[0123] The rich product 5 from cracking aromatization and Fischer-Tropsch synthesis liquefied petroleum gas (LPG) 4 were separated together in gas separation unit G to produce dry gas 10, propylene 11, propane 12, and a mixed C4 component 13. The mixed C4 component 13 was then separated at 75°C, 1.5 MPa, a light-to-oil ratio (V / V) of 30, and a space velocity of 20 h⁻¹. -1 After selective hydrogenation of the diene via Ni-Mo / Al₂O₃ catalyst, it is mixed with methanol 2 and then introduced into the C₄ etherification unit H. The reaction is carried out at a temperature of 60°C, a pressure of 1 MPa, and a liquid hourly space velocity of 0.5 h⁻¹. -1 The pre-etherification reaction was completed under the condition that the alcohol-to-olefin molar ratio was 1.5. The pre-etherified product entered a catalytic distillation column and under the conditions of column top temperature 60℃, column bottom temperature 135℃, bed temperature 65℃ and pressure 1.3MPa, it was deeply etherified by catalytic distillation to obtain methyl tert-butyl ether and etherified C4 component 14.

[0124] The C4 component after etherification, along with propylene comprising 75% of the total propylene content of propylene 11, is then introduced into alkylation unit I. Alkylation is carried out under concentrated sulfuric acid conditions at a reaction temperature of 15°C and an alkyl-to-olefin ratio of 12:1 to yield alkylated gasoline and n-butane. n-Butane 18 then enters isomerization unit J, where it undergoes alkylation at 220°C, a pressure of 2.0 MPa, and a space velocity of 1.8 h⁻¹. -1 Under conditions where the hydrogen / hydrocarbon ratio is 1.2, an isomerization reaction occurs to produce isobutane, which is then returned to alkylation unit I to regenerate alkylated gasoline.

[0125] The cracked aromatized heavy gasoline fraction, etherified light gasoline fraction, methyl tert-butyl ether, and alkylated gasoline fraction are mixed and blended in gasoline pool K to obtain the final gasoline product; dry gas 10 can be used as fuel gas in the auxiliary combustion chamber C of the cracked aromatization unit; propane 12 exits the unit as liquefied petroleum gas; and cracked aromatized slurry 9 can enter reactor B for reprocessing.

[0126] The yields, composition, and RON octane numbers of gasoline products obtained by mixing cracked aromatized heavy gasoline fraction, etherified light gasoline fraction, methyl tert-butyl ether, and alkylated gasoline fraction are shown in Table 2.

[0127] Example 4

[0128] This embodiment uses a mixture of Fischer-Tropsch synthetic wax and Fischer-Tropsch synthetic heavy oil in a weight ratio of 3:1 and methanol as raw materials. Cat-4 catalyst with LaZn-modified ZSM-5 molecular sieve as the active component is selected, and the dry basis content of the molecular sieve in the catalyst is 20%. The ratio of the Fischer-Tropsch synthetic wax and heavy oil mixture to methanol is 0.2. The Fischer-Tropsch synthetic wax and heavy oil mixture is first preheated to 200°C, then atomized with methanol before entering the methanol-methanol mixture. Figure 1 In the fluidized bed reactor A shown, the reactor temperature is 450℃ and the weight hourly space velocity is 30h. -1 The reaction proceeds under a pressure of 0.30 MPa and a catalyst-to-oil ratio of 10.0, resulting in a cracking aromatization reaction and yielding intermediate products. These intermediate products rise into a settling tank, where a cyclone separator at the top removes any remaining catalyst. The final product then enters a fractionation system, where it is fractionated to produce cracking aromatization gas products, cracking aromatization light gasoline fraction, cracking aromatization heavy gasoline fraction, cracking aromatization diesel fraction, and cracking aromatization heavy oil. The deactivated catalyst, after coking, moves downwards with the bed and enters the stripping section. After steam stripping, it is fed through a regenerated inclined tube into a coking tank and regenerator for coking regeneration. The resulting regenerated catalyst is then recycled into the fluidized bed reactor via a regeneration inclined tube.

[0129] Cracking and aromatizing of light gasoline at 80℃, 1.0 MPa, light gasoline ratio (V / V) 30, and space velocity 10 h⁻¹ -1 After selective hydrogenation of dienes using Ni-Mo / Al2O3 catalyst, the mixture is combined with methanol and then fed into a light gasoline etherification unit at 60°C and a weight hourly space velocity (WHSV) of 2 h⁻¹. -1 Pre-etherification was completed under the conditions of pressure 1 MPa and oil-to-ethanol ratio (V / V) 13. The pre-etherified product entered a catalytic distillation column and was deeply etherified by distillation with a sulfonic acid-type strong acid cation exchange resin catalyst at a top temperature of 50°C and a bottom temperature of 150°C to obtain etherified light gasoline 16.

[0130] The rich product 5 from cracking aromatization and Fischer-Tropsch synthesis liquefied gas 4 are separated together in gas separation unit G to produce dry gas 10, propylene 11, propane 12, and a mixed C4 component 13. The mixed C4 component 13 is then separated at 70°C, 0.8 MPa, a hydrogen-to-oil ratio (V / V) of 40, and a space velocity of 20 h⁻¹. -1 After selective hydrogenation of the diene via Ni-Mo / Al₂O₃ catalyst, it is mixed with methanol 2 and then introduced into the C₄ etherification unit H. The reaction is carried out at a temperature of 50°C, a pressure of 1 MPa, and a liquid hourly space velocity of 1.2 h⁻¹. -1 The pre-etherification reaction was completed under the condition that the alcohol-to-olefin molar ratio was 1.2. The pre-etherified product entered a catalytic distillation column and under the conditions of column top temperature 40℃, column bottom temperature 125℃, bed temperature 50℃ and pressure 1MPa, it underwent deep etherification by catalytic distillation to obtain methyl tert-butyl ether and etherified C4 component 14.

[0131] The C4 component after etherification, along with propylene comprising 90% of the total propylene content of propylene 11, is then introduced into alkylation unit I. Alkylation is carried out under concentrated sulfuric acid conditions at a reaction temperature of 8°C and an alkyl-to-olefin ratio of 6:1, yielding alkylated gasoline and n-butane. n-Butane 18 then enters isomerization unit J, where it undergoes alkylation at 230°C, a pressure of 2.0 MPa, and a space velocity of 2.0 h⁻¹. -1 Under conditions where the hydrogen / hydrocarbon ratio is 1.5, an isomerization reaction occurs to produce isobutane, which is then returned to alkylation unit I to regenerate alkylated gasoline.

[0132] The cracked aromatized heavy gasoline fraction, etherified light gasoline fraction, methyl tert-butyl ether, and alkylated gasoline fraction are mixed and blended in gasoline pool K to obtain the final gasoline product; dry gas 10 can be used as fuel gas in the auxiliary combustion chamber C of the cracked aromatization unit; propane 12 exits the unit as liquefied petroleum gas; and cracked aromatized slurry 9 can enter reactor B for reprocessing.

[0133] The yields, composition, and RON octane numbers of gasoline products obtained by mixing cracked aromatized heavy gasoline fraction, etherified light gasoline fraction, methyl tert-butyl ether, and alkylated gasoline fraction are shown in Table 2.

[0134] Comparative Example 1CN109694743A: Blended gasoline product of Example 3

[0135] Comparative Example 2: Commercially available 95# clean gasoline

[0136] The gasoline products of Examples 1-3 and Comparative Examples 1-2 were subjected to physicochemical property analysis and engine exhaust pollutant emission bench tests. (GB 18352.6-2016 Limits and Measurement Methods for Pollutant Emissions from Light-Duty Vehicles (China VI))

[0137] Table 2 shows the yield, product composition, and octane number of gasoline products in the examples.

[0138]

[0139] *: Content % refers to the percentage of each component in the blended gasoline.

[0140] The gasoline yields described in the above embodiments are all calculated based on the total hydrocarbon content in the feed.

[0141] As can be seen from the reaction evaluation data listed in Table 2, the method and apparatus for producing ultra-clean gasoline by coupling methanol with Fischer-Tropsch synthesis provided by this invention produce Fischer-Tropsch synthetic oil products with superior and cleaner integrated gasoline (i.e., blended clean gasoline). In particular, the total gasoline yield from a single-pass conversion can reach more than 83%, and the octane number of the integrated gasoline is greater than 95, which fully demonstrates the advantages of the method of this invention in processing Fischer-Tropsch synthetic oil products.

[0142] The embodiments of the present invention have been described in detail above. It will be obvious to those skilled in the art that many improvements and changes can be made without departing from the basic spirit of the present invention, and all such changes and improvements are within the protection scope of the present invention.

Claims

1. A process for the production of ultra clean gasoline by coupling Fischer-Tropsch synthesis oil product with methanol, wherein, The method includes the following steps: (1) Fischer-Tropsch synthetic oil is preheated, atomized and then mixed with methanol and fed into the cracking aromatization reaction unit to carry out cracking aromatization reaction to obtain cracking aromatization products; (2) The above-mentioned cracked aromatization products are fed into the oil and gas fractionation unit for oil and gas fractionation to obtain cracked aromatization gas products, cracked aromatization light gasoline fraction, cracked aromatization heavy gasoline fraction, cracked aromatization diesel fraction and cracked aromatization heavy oil fraction, wherein the cracked aromatization heavy oil fraction is returned to step (1) for reprocessing; (3) The above-mentioned cracked aromatized light gasoline fraction is mixed with methanol and then fed into the light gasoline etherification unit for light gasoline etherification reaction to obtain etherified light gasoline fraction; (4) The cracked aromatization gas product described in step (2) is optionally mixed with Fischer-Tropsch synthesis liquefied gas and then sent to a gas separation unit for gas separation to obtain dry gas, propylene, propane and C4 components. (5) The above C4 component is mixed with methanol and then fed into the C4 etherification unit for C4 etherification reaction to obtain the etherified C4 component and methyl tert-butyl ether; (6) The above-mentioned C4 component after etherification is mixed with a portion of the propylene obtained in step (4) and then fed into the alkylation unit for alkylation reaction to obtain alkylated gasoline fraction and n-butane; wherein the n-butane is fed into the n-butane isomerization unit for isomerization reaction to obtain isobutane, and the isobutane is recycled back to the above-mentioned alkylation unit for reprocessing. (7) The dry gas and part of the propane described in step (4) are fed into the auxiliary fuel chamber as fuel gas to heat the cracking aromatization reaction unit described in step (1). (8) Recycle another portion of the propylene obtained in step (4) back to the cracking aromatization reaction unit of step (1); (9) By blending the cracked aromatized heavy gasoline fraction, the etherified light gasoline fraction, the methyl tert-butyl ether and the alkylated gasoline fraction, an ultra-clean gasoline product is obtained.

2. The method of claim 1, wherein, In step (1), the preheating temperature of the Fischer-Tropsch synthetic oil is 100-350℃.

3. The method of claim 2, wherein, In step (1), the preheating temperature of the Fischer-Tropsch synthetic oil is 150-300℃.

4. The method according to any one of claims 1-3, wherein, In step (1), the weight ratio of the Fischer-Tropsch synthetic oil to methanol is (0.05-0.5):

1.

5. The method of claim 4, wherein, In step (1), the weight ratio of the Fischer-Tropsch synthetic oil to methanol is (0.15-0.45):

1.

6. The method of any one of claims 1-3, wherein, In step (1), the reaction conditions for the cracking aromatization reaction are: temperature 350-500℃, pressure 0.01-1.00MPa, and weight hourly space velocity 0.5-40 h⁻¹. -1 The ratio of agent to oil is 2.0-10.

0.

7. The method of claim 6, wherein, In step (1), the reaction conditions for the cracking aromatization reaction are: temperature 350-450℃, pressure 0.1-0.7MPa, and weight hourly space velocity 1-30h. -1 The ratio of agent to oil is 2.0-8.

0.

8. The method of any one of claims 1-3, wherein, In step (1), the cracking aromatization reaction is carried out in the presence of a cracking aromatization catalyst.

9. The method of claim 8, wherein, In step (1), the main active component of the cracking aromatization catalyst is a ten-membered ring pore molecular sieve.

10. The method of claim 9, wherein, In step (1), the dry basis content of the ten-membered ring channel molecular sieve is 10-60m based on the total dry basis weight of the catalyst.

11. The method of claim 10, wherein, In step (1), the dry basis content of the ten-membered ring channel molecular sieve is 20-50m based on the total dry basis weight of the catalyst.

12. The method of claim 9, wherein, In step (1), the ten-membered ring pore molecular sieve includes one or more of ZSM-5, ZSM-11, ZSM-22 and ZSM-35 molecular sieves modified with any one of P, Zn, Ag and rare earth metals.

13. The method of any one of claims 1-3, wherein, In step (3), the light gasoline etherification reaction includes: mixing the cracked aromatized light gasoline fraction with methanol, first performing pre-etherification through one or more fixed-bed reactions, and then performing deep etherification in the presence of an etherification catalyst in a catalytic distillation tower.

14. The method of claim 13, wherein, In step (3), the pre-etherification reaction conditions are: reaction temperature 30-100℃, reaction pressure 0.5-2MPa, liquid space velocity 0.5-5.0h -1 , and volume ratio of oil alcohol 5-15.

15. The method of claim 14, wherein, In step (3), the pre-etherification reaction conditions are: reaction temperature 40-80℃, reaction pressure 0.8-1.5 MPa, liquid space velocity 1.0-4.0 h -1 , and volume ratio of oil to alcohol 8-13.

16. The method of claim 13, wherein, In step (3), the conditions for deep etherification are: top temperature of 35-70℃, bottom temperature of 100-160℃, and the catalyst is an acidic catalyst.

17. The method of claim 16, wherein, In step (3), the deeply etherified catalyst includes one or more of molecular sieves, heteropoly acids, and resin catalysts.

18. The method of claim 17, wherein, In step (3), the catalyst for deep etherification is a sulfonic acid type strong acid cation exchange resin catalyst.

19. The method of any one of claims 16-18, wherein, In step (3), the conditions for deep etherification are: top temperature of 38-65℃ and bottom temperature of 110-155℃.

20. The method of any one of claims 1-3, wherein, In step (3), prior to mixing with methanol, the light gasoline etherification reaction further includes subjecting the cracked aromatized light gasoline fraction to a light gasoline selective hydrogenation dediolefin reaction.

21. The method of claim 20, wherein, In step (3), the light gasoline selective hydrode-diene reaction conditions are: reaction temperature 70-120℃, pressure 0.5-2.0 MPa, hydrogen / oil volume ratio 20-40, space velocity 2-36 h -1 , and the catalyst is a supported catalyst.

22. The method of claim 21, wherein, In step (3), the catalyst for the selective hydrodediolefin reaction of light gasoline includes a noble metal catalyst with one or more noble metals selected from Pt and Pd as the active component and / or a catalyst with one or more non-noble metals selected from Mo, W, Co and Ni as the active component.

23. The method of claim 22, wherein, In step (3), the catalyst for the selective hydrogenation dediolefin reaction of light gasoline is a Ni-Mo / Al2O3 catalyst.

24. The method of any one of claims 21-23, wherein, In step (3), the conditions for the selective hydrogenation dediolefin reaction of light gasoline are: reaction temperature 80-100℃, pressure 0.8-1.5 MPa, hydrogen-to-oil volume ratio 25-35, and space velocity 10-30 h⁻¹. -1 .

25. The method of any one of claims 1-3, wherein, In step (5), the C4 etherification reaction includes a pre-etherification reaction and a catalytic distillation deep etherification reaction.

26. The method of claim 25, wherein, In step (5), the reaction conditions for the pre-etherification reaction are: reaction temperature 30-70℃, reaction pressure 0-1.5MPa, and liquid hourly space velocity 0.5-5.0h. -1 The molar ratio of alcohols to olefins is 0.9-1.

5.

27. The method of claim 26, wherein, In step (5), the reaction conditions of the pre-etherification reaction are: reaction temperature 40-65℃, reaction pressure 0.3-1.0 MPa, liquid space velocity 1.0-3.0 h -1 , alcohol-olefin molar ratio 1.0-1.

2.

28. The method of claim 25, wherein, In step (5), the catalytic distillation column conditions for the catalytic distillation deep etherification reaction are: bed temperature 35-70℃, reaction pressure 0-1.5MPa, column top temperature 40-60℃, and column bottom temperature 100-140℃.

29. The method of claim 28, wherein, In step (5), the conditions of the catalytic distillation column for the catalytic distillation deep etherification reaction are: bed temperature 40-65℃, reaction pressure 0.3-0.8MPa, column top temperature 45-60℃, and column bottom temperature 110-135℃.

30. The method of any one of claims 1-3, wherein, In step (5), the C4 etherification unit further includes a C4 selective hydrogenation dediene unit, wherein the reaction conditions for the C4 selective hydrogenation dediene unit are: reaction temperature 70-120℃, pressure 0.5-2.0 MPa, hydrogen-to-oil volume ratio 20-40, and space velocity 2-36 h⁻¹. -1 The catalyst is a supported catalyst.

31. The method of claim 30, wherein, In step (5), the catalyst for the C4 selective hydrogenation dediolefin unit includes a noble metal catalyst with one or more noble metals selected from Pt and Pd as the active component and / or a catalyst with one or more non-noble metals selected from Mo, W, Co, and Ni as the active component.

32. The method of claim 31, wherein, In step (5), the catalyst for the C4 selective hydrogenation dediolefin unit is a Ni-Mo / Al2O3 catalyst.

33. The method of claim 30, wherein, In step (5), the reaction conditions for the C4 selective hydrogenation dediene unit are: reaction temperature 75-100℃, pressure 0.8-1.7 MPa, hydrogen-to-oil volume ratio 30-40, and space velocity 2-20 h⁻¹. -1 .

34. The method of any one of claims 1-3, wherein, In step (6), the alkylation reaction is a sulfuric acid alkylation reaction, and the reaction conditions for the sulfuric acid alkylation reaction are: reaction temperature -10~30℃, alkyl-to-olefin ratio (6~12):

1.

35. The method of claim 34, wherein, In step (6), the reaction conditions for the sulfuric acid alkylation reaction are: reaction temperature -5~15℃, alkane-to-alkene ratio (7~10):

1.

36. The method of any one of claims 1-3, wherein, In step (6), the propylene accounts for 50-100% of the total propylene amount in step (4).

37. The method of any one of claims 1-3, wherein, In step (6), the reaction conditions for the isomerization reaction are: reaction temperature 210-230℃, pressure 1.5-2.2MPa, and space velocity 1.0-2.2h. -1 The hydrogen-to-hydrogen ratio is 1.0-2.

0.

38. The method of claim 37, wherein, In step (6), the reaction conditions for the isomerization reaction are: reaction temperature 215-225℃, pressure 1.6-2.2 MPa, and space velocity 1.8-2.2 h⁻¹. -1 The hydrogen-to-hydrogen ratio is 1.2-1.

5.

39. The method of claim 1, wherein, The method includes the following steps: (1) The Fischer-Tropsch synthetic oil is preheated to 100-350℃, atomized, and then mixed with methanol at a weight ratio of (0.05-0.5):1 and fed into the cracking aromatization reaction unit. The reaction is carried out at a temperature of 350-500℃, a pressure of 0.01-1.00MPa, and a weight hourly space velocity of 0.5-40 h⁻¹. -1 The cracking aromatization reaction was carried out under the condition of an oil-to-crack ratio of 2.0-10.0 to obtain the cracking aromatization product; (2) The above-mentioned cracked aromatization products are fed into the oil and gas fractionation unit for oil and gas fractionation to obtain cracked aromatization gas products, cracked aromatization light gasoline fraction, cracked aromatization heavy gasoline fraction, cracked aromatization diesel fraction and cracked aromatization heavy oil fraction, wherein the cracked aromatization heavy oil fraction is returned to step (1) for reprocessing; (3) The cracked aromatized light gasoline fraction is selectively hydrogenated to remove dienes and then mixed with methanol. The reaction is carried out at a temperature of 30-100℃, a pressure of 0.5-2MPa, and a liquid hourly space velocity of 0.5-5.0h. -1 Pre-etherification is carried out under conditions of an oil-to-ethanol volume ratio of 5-15, followed by deep etherification in a catalytic distillation column at a top temperature of 35-70℃ and a bottom temperature of 100-160℃ in the presence of a sulfonic acid-type strong acid cation exchange resin catalyst to obtain etherified light gasoline fraction; the selective hydrode-diolefin conditions are: supported catalyst Ni-Mo / Al2O3, reaction temperature 70-120℃, pressure 0.5-2.0 MPa, hydrogen-to-oil volume ratio 20-40, and space velocity 2-36 h⁻¹. -1 ; (4) The cracked aromatization gas product described in step (2) is optionally mixed with Fischer-Tropsch synthesis liquefied gas and then sent to a gas separation unit for gas separation to obtain dry gas, propylene, propane and C4 components. (5) The above C4 components were tested under the following conditions: catalyst Ni-Mo / Al2O3, temperature 70-120℃, pressure 0.5-2.0 MPa, hydrogen-to-oil volume ratio 20-40, and space velocity 2-36 h⁻¹. -1 Under specific conditions, the diene is selectively hydrogenated, then mixed with methanol, and fed into a C4 etherification unit. The reaction is carried out at a temperature of 30-70℃, a pressure of 0-1.5 MPa, and a liquid hourly space velocity of 0.5-5.0 h⁻¹. -1 The pre-etherification reaction was carried out under the condition of an alcohol-olefin molar ratio of 0.9-1.

5. The pre-etherification product entered a catalytic distillation column and underwent a deep etherification reaction under the conditions of a bed temperature of 35-70℃, a reaction pressure of 0-1.5MPa, a column top temperature of 40-60℃, and a column bottom temperature of 100-140℃ to obtain the etherified C4 component and methyl tert-butyl ether. (6) The above-mentioned C4 component after etherification is mixed with a portion of the propylene obtained in step (4) and then fed into an alkylation unit for alkylation reaction at a reaction temperature of -10~30℃ and an alkyl-to-olefin ratio of (6~12):1 to obtain alkylated gasoline fraction and n-butane; wherein, the n-butane is introduced into a n-butane isomerization unit at a reaction temperature of 210-230℃, a pressure of 1.5-2.2MPa, and a space velocity of 1.0-2.2h. -1 The isomerization reaction is carried out under conditions of hydrogen-to-hydrogen ratio of 1.0-2.0 to obtain isobutane, and the isobutane is recycled back to the above-mentioned alkylation unit for reprocessing; (7) The dry gas and part of the propane described in step (4) are fed into the auxiliary fuel chamber as fuel gas to heat the regeneration system of the cracking aromatization reaction unit in step (1). (8) Recycle another portion of the propylene obtained in step (4) back to the cracking aromatization reaction unit of step (1); (9) By blending the cracked aromatized heavy gasoline fraction, the etherified light gasoline fraction, the methyl tert-butyl ether and the alkylated gasoline fraction, an ultra-clean gasoline product is obtained.

40. An apparatus for carrying out the method of any one of claims 1-39, wherein, The device includes the following units: A cracking aromatization reaction unit, optionally equipped with a catalyst regenerator and an auxiliary combustion chamber; An oil and gas fractionation unit, the inlet of which is fluidly connected to the upper outlet of the cracking aromatization reaction unit, and the lower outlet of which is fluidly connected to the cracking aromatization heavy oil inlet of the cracking aromatization reaction unit. A gas separation unit, the inlet of which is fluidly connected to the cracking aromatization gas product outlet of the oil and gas fractionation unit; A light gasoline etherification unit, wherein the inlet of the light gasoline etherification unit is fluidly connected to the outlet of the cracked aromatized light gasoline fraction of the oil and gas fractionation unit; The lower outlet of the gas separation unit is connected to the inlet of the C4 etherification unit in a fluid communication manner. An alkylation unit, the inlet of which is fluidly connected to the outlet of the etherified C4 component of the C4 etherification unit and the propylene outlet of the gas separation unit; The n-butane isomerization unit has its inlet connected in fluid communication to the n-butane outlet of the alkylation unit, and its outlet connected in fluid communication to the inlet of the alkylation unit. The gasoline tank is connected in fluid communication with the oil and gas fractionation unit, the light gasoline etherification unit, the C4 etherification unit, and the alkylation unit.

41. The apparatus of claim 40, wherein, The cracking aromatization reaction unit includes a first cracking aromatization reaction unit and a second cracking aromatization reaction unit. The first cracking aromatization reaction unit is used to process the atomized Fischer-Tropsch synthetic oil and methanol into the cracking aromatization reaction. The second cracking aromatization reaction unit is used to reprocess the cracked aromatized heavy oil produced by the oil and gas fractionation unit and then further feed it into the first cracking aromatization reaction unit.

42. The apparatus of claim 40 or 41, wherein, The cracking aromatization reaction unit is equipped with a catalyst regenerator and an auxiliary combustion chamber.

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