Road asphalt and synthesis method thereof

Abstract

The invention discloses road asphalt and a synthesis method thereof. The synthesis method of the road asphalt comprises the following steps: (1) fractionating catalytic slurry oil to obtain four components, namely a light component, a middle component, a heavy component and kettle residues; (2) respectively contacting the light component and the heavy component separated in the step (1) with a catalyst to react to obtain a product I and a product II, and mixing the medium component separated in the step (1) with a cross-linking agent to react to obtain a product III; the kettle residues in the step (1) and oxygen-containing gas are mixed for a reaction, and a product IV is obtained; and (3) blending all products obtained in the step (2) to obtain the road asphalt. According to the preparation method provided by the invention, the oil slurry resource which is relatively low in additional value and rich in resource is utilized, the components of the catalytic oil slurry are subjected to catalytic reaction, and a specific compound is matched for modulation, so that the road asphalt material meeting the road petroleum asphalt A-grade technical requirements is obtained.

Description

Technical Field

[0001] The present invention relates to the cross - field of petrochemical industry and heavy oil processing, and specifically relates to a road asphalt and its synthesis method. Background Art

[0002] Catalytic slurry is the remaining aromatic - rich waste slurry discharged from the catalytic cracking unit during the petroleum refining process. In terms of composition, it has a high aromatic content, mostly above 55%, a low content of gum and asphaltene, and a saturated hydrocarbon content mostly below 35%. It is a high - quality component for improving the quality of asphalt. However, the catalytic slurry itself has a low viscosity and a low degree of condensation, and its polycyclic aromatic hydrocarbons have unstable active carbon bonds, making it prone to oxidative condensation reactions. The actual application effect shows that directly using catalytic slurry to blend asphalt will lead to a series of problems such as poor temperature - sensitivity performance and poor anti - aging performance of asphalt products, affecting the service life of the road surface. Affected by the properties of catalytic slurry itself, its addition amount in road asphalt is generally not more than 20%, and the utilization rate is low.

[0003] CN1102847A discloses a method for producing heavy traffic road asphalt by oxidizing catalytic slurry with ferric trichloride or phosphorus pentoxide as a catalyst and then blending it with solvent - deasphalted asphalt or vacuum residue. Since there are many light components in the slurry, direct oxidation will result in a high volatilization rate of light components, reducing the effective utilization rate of the slurry and polluting the environment.

[0004] CN115820289A discloses a method for preparing mesophase pitch. In this method, light aromatic oil, medium aromatic oil, and heavy aromatic oil in catalytic slurry are respectively polymerized and distilled into low - softening - point mesophase pitch, medium - softening - point mesophase pitch, and high - softening - point mesophase pitch, and then mixed and modulated in different proportions to obtain mesophase pitch with different properties. The preparation process used in this method does not use any catalyst, the reaction randomness is strong, the reaction conversion will vary greatly for catalytic slurries obtained from different raw materials, the softening point of the mesophase obtained after the reaction is too high and is not suitable for road asphalt, and the still residue after distillation is not utilized. Summary of the Invention

[0005] Aiming at the deficiencies of the prior art, the present invention provides a road asphalt and its synthesis method. The synthesis method of the road asphalt provided by the present invention utilizes the slurry resource with low added value and rich resources, conducts catalytic reactions on the components of catalytic slurry, and is modulated with specific compounds to obtain a road asphalt material that meets the technical requirements of Grade A of road petroleum asphalt.

[0006] The first aspect of the present invention provides a synthesis method of road asphalt, including the following steps:

[0007] (1) Fractionate catalytic slurry into four components: light component, medium component, heavy component, and still residue;

[0008] (2) React the light fraction and heavy fraction separated in step (1) with a catalyst respectively to obtain Product I and Product II, mix the middle fraction separated in step (1) with a crosslinking agent for reaction to obtain Product III; mix the still residue in step (1) with an oxygen-containing gas for reaction to obtain Product IV;

[0009] (3) Blend Product I, Product II, Product III and Product IV obtained in step (2) to obtain the road asphalt material composite.

[0010] Furthermore, the catalytic slurry is a catalytic slurry produced by a catalytic cracking unit from natural petroleum, and is a mixture rich in aromatics; the content of aromatics in the catalytic slurry is 50% - 90% (by mass). The mass content of paraffins in the catalytic slurry is less than 5%, and the mass content of naphthenes is less than 15%.

[0011] Furthermore, the slurry fractionation method in step (1) is preferably carried out by vacuum distillation, and the vacuum degree is 2 - 5 mbar.

[0012] Furthermore, the cut-off point between the light fraction and the middle fraction in step (1) is 340°C - 360°C, the cut-off point between the middle fraction and the heavy fraction is 430°C - 450°C, and the cut-off point between the heavy fraction and the still residue is 510°C - 530°C.

[0013] Furthermore, the crosslinking agent in step (2) is one or more of elemental sulfur, sulfur monochloride, carbon disulfide, thiazoles, thiurams, sulfenamides, guanidines, dithiocarbamates, aldehyde amines, xanthates, thioureas, and isocyanates, and preferably elemental sulfur or carbon disulfide.

[0014] Furthermore, the catalyst in step (2) is one or more of boron halogen compounds and halogen acids, and preferably hydrofluoric acid, boron fluoride, or boron fluoride / hydrofluoric acid. The mass ratio of boron fluoride to hydrofluoric acid is (0.01 - 6):3.

[0015] Furthermore, in step (2), the light fraction in step (1) is reacted under the action of a catalyst, and the mass ratio of the light fraction to the catalyst is (1 - 2):(2 - 3).

[0016] Further, in step (2), the light components and the catalyst in step (1) are added to a reaction kettle, and a stirring reaction is carried out during the sealing process. The stirring speed of the reaction kettle is 100 r / min to 200 r / min, the reaction temperature is 150 °C to 180 °C, the reaction pressure is 1.0 MPa to 1.5 MPa, and the reaction time is 1 h to 3 h. Then, under the condition that the stirring speed and the reaction pressure remain unchanged, the reaction temperature is adjusted to 200 °C to 260 °C, and the reaction is carried out for another 1 h to 3 h. When the softening point of the material reaches 32 - 38 °C, the reaction is stopped to obtain Product I.

[0017] Further, in step (2), the middle components in step (1) are reacted under the action of a crosslinking agent, and the mass ratio of the middle components to the crosslinking agent is (10 - 20):(1 - 5).

[0018] Further, in step (2), the middle components and the crosslinking agent in step (1) are added to a reaction kettle, the reaction kettle is sealed after nitrogen replacement, and a reaction is carried out during the stirring process. The stirring speed of the reaction kettle is 100 r / min to 200 r / min, the reaction temperature is 280 °C to 320 °C, the reaction pressure is 0.5 MPa to 1.2 MPa, and the reaction time is 3 h to 8 h. Then, under the condition that the stirring speed and the reaction pressure remain unchanged, the reaction temperature is adjusted to 360 °C to 400 °C, and the reaction is carried out for another 0.1 h to 2 h. When the softening point of the material reaches 77 - 83 °C, the reaction is stopped to obtain Product II.

[0019] Further, in step (2), the heavy components in step (1) are reacted under the action of a catalyst, and the mass ratio of the heavy components to the catalyst is (1 - 2):(3 - 5).

[0020] Further, in step (2), the heavy components and the catalyst in step (1) are added to a reaction kettle, and a stirring reaction is carried out during the sealing process. The stirring speed of the reaction kettle is 100 r / min to 200 r / min, the reaction temperature is 200 °C to 260 °C, the reaction pressure is 1.5 MPa to 2.0 MPa, and the reaction time is 1 h to 5 h. When the softening point of the material reaches 42 - 48 °C, the reaction is stopped to obtain Product III.

[0021] Further, in step (2), the kettle residue in step (1) is added to a reaction kettle, and an oxygen-containing gas is introduced during the stirring process; the stirring speed of the reaction kettle is 100 r / min to 200 r / min, the reaction temperature is 150 °C to 200 °C, the flow rate of the oxygen-containing gas is 6 - 15 L / min, and after the reaction time of 2 h to 5 h, when the softening point of the material reaches 42 - 48 °C, the reaction is stopped to obtain Product IV. The oxygen-containing gas is preferably air.

[0022] Further, in step (3), the products I, II, III, and IV obtained in step (2) are blended at a stirring speed of 200 r / min to 500 r / min, a stirring temperature of 170 °C to 200 °C, and a stirring time of 1 h to 2 h to obtain a road asphalt material.

[0023] Further, in step (3), the mass ratio of the products I, II, III, and IV obtained in step (2) is (10 - 20):(30 - 45):(10 - 20):(25 - 35).

[0024] In the second aspect of the present invention, a road asphalt prepared by the above preparation method is provided.

[0025] Further, the road asphalt material meets the technical requirements of road petroleum asphalt in JTG F40. Among them, the penetration (0.1 mm) of the road asphalt material of the present invention at 25 °C is 20 - 60, meeting Grade A of No. 30 and Grade A of No. 50; the softening point is not less than 49 °C, meeting Grade A of No. 30 and Grade A of No. 50; the ductility at 10 °C is not less than 10 cm, meeting Grade A of No. 30 and Grade A of No. 50.

[0026] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0027] (1) In the method provided by the present invention, the separation of each component of the slurry is carried out, and the directional control reaction is carried out by using the characteristics of each component of the slurry to realize the fractional reaction of the slurry. Through the crosslinking and polycondensation reactions of the present invention, the unsaturated bonds in the catalytic slurry are polycondensed and crosslinked, reducing the small molecule substances and increasing the macromolecule substances in the catalytic slurry, and the thermal stability and chemical stability of the molecules are better, thereby improving the performance stability of the road asphalt material. Moreover, the present invention also conducts catalytic reactions on the light components and heavy components, increasing the degree of polycondensation of the oligomeric aromatic rings in the catalytic slurry. By controlling the reaction conditions in a closed container, the volatilization of the light components can be effectively reduced, and the utilization rate of the light components can be improved.

[0028] (2) The various components in the road asphalt material provided by the present invention cooperate with each other and act together, making the material have outstanding stability, meeting the technical requirements of Grade A of the existing road petroleum asphalt, and while taking into account the performance of the road asphalt, the slurry resources are fully and reasonably utilized, having a high resource utilization value. Specific Embodiments

[0029] The technical solutions and effects of the present invention will be further described below through examples. The examples are implemented on the premise of the technical solutions of the present invention, and the detailed implementation methods and specific operation processes are given, but the protection scope of the present invention is not limited to the following examples.

[0030] Example 1

[0031] Take 6 kg of catalytic slurry (the slurry is the catalytic slurry produced by the catalytic cracking unit of natural petroleum and is a mixture rich in aromatics. The content of aromatics in the slurry is 68% (by mass). The mass content of paraffins in the slurry is 4.7%, and the mass content of naphthenes is 10.8%) and conduct vacuum distillation. The vacuum degree is 3.2 mbar and cutting is carried out to obtain light components at room temperature to 350 °C, middle components at 350 °C to 420 °C, heavy components at 420 °C to 500 °C, and still residues above 500 °C respectively.

[0032] Add the light components at room temperature to 350 °C and hydrofluoric acid catalyst into the reaction kettle and stir for reaction. The mass ratio of the light components to the catalyst is 2:2, the stirring speed is 150 r / min, the reaction temperature is 150 °C, the reaction pressure is 1.2 MPa, and the reaction time is 2 h. Then, under the conditions of unchanged stirring speed and reaction pressure, adjust the reaction temperature to 200 °C and continue the reaction for 2 h. When the softening point of the material reaches 35 °C, stop the reaction to obtain Product I.

[0033] Add the middle components at 350 °C to 420 °C and elemental sulfur cross-linking agent into the reaction kettle and stir for reaction. The mass ratio of the middle components to the catalyst is 20:3. After purging with nitrogen, seal the reaction kettle and carry out the reaction during stirring. The stirring speed is 150 r / min, the reaction temperature is 300 °C, the reaction pressure is 1.0 MPa, and the reaction time is 5 h. Then, under the conditions of unchanged stirring speed and reaction pressure, adjust the reaction temperature to 380 °C and continue the reaction for 1 h. When the softening point of the material reaches 80 °C, stop the reaction to obtain Product II.

[0034] Add the heavy components at 420 °C to 500 °C and hydrofluoric acid catalyst into the reaction kettle and stir for reaction during the sealing process. The mass ratio of the heavy components to the catalyst is 2:5, the stirring speed is 150 r / min, the reaction temperature is 200 °C, the reaction pressure is 1.8 MPa, and the reaction time is 2 h. When the softening point of the material reaches 45 °C, stop the reaction to obtain Product III.

[0035] Add the still residues above 500 °C into the reaction kettle, introduce air during stirring. The stirring speed is 150 r / min, the reaction temperature is 180 °C, the air flow rate is 8 L / min. After the reaction time of 3 h, when the softening point of the material reaches 45 °C, stop the reaction to obtain Product IV.

[0036] Product I, Product II, Product III, and Product IV were stirred and mixed in a mass ratio of 20:32:18:30 at a stirring speed of 300 r / min, a stirring temperature of 180°C, and a stirring time of 1.5 hours to obtain a road asphalt material. The components and their proportions after oil slurry separation are shown in Table 1 below.

[0037] Example 2

[0038] 6 kg of catalytic oil slurry (same as in Example 1) was distilled by a reduced pressure distillation process with a vacuum degree of 3.2 mbar, and cut to obtain a light component at room temperature to 350°C, a medium component at 350°C to 420°C, a heavy component at 420°C to 500°C, and a kettle residue greater than 500°C.

[0039] A light component at room temperature to 350° C. and a boron fluoride / hydrofluoric acid catalyst were added to a reactor and stirred for reaction. The mass ratio of the light component to the catalyst was 2:3, the mass ratio of boron fluoride to hydrofluoric acid was 0.02:3, the stirring speed was 150 r / min, the reaction temperature was 160° C., the reaction pressure was 1.0 MPa, and the reaction time was 1.5 h. Then, under the conditions of constant stirring speed and reaction pressure, the reaction temperature was adjusted to 250° C. and the reaction was continued for another 1 h. When the softening point of the material reached 35° C., the reaction was stopped to obtain product I.

[0040] The middle component at 350°C to 420°C and the elemental sulfur cross-linking agent were added to the reactor and stirred for reaction. The mass ratio of the middle component to the catalyst was 20:5. The reactor was sealed after nitrogen replacement and the reaction was carried out during stirring. The stirring speed was 150 r / min, the reaction temperature was 320°C, the reaction pressure was 0.6 MPa, and the reaction time was 4 h. Then, under the conditions of constant stirring speed and reaction pressure, the reaction temperature was adjusted to 360°C and the reaction was continued for another 1.5 h. When the softening point of the material reached 80°C, the reaction was stopped to obtain product II.

[0041] A heavy component at 420°C to 500°C and a boron fluoride / hydrofluoric acid catalyst were added to a reactor and stirred in a closed process. The mass ratio of the heavy component to the catalyst was 2:4, the mass ratio of boron fluoride to hydrofluoric acid was 0.1:3, the stirring speed was 150 r / min, the reaction temperature was 210°C, the reaction pressure was 1.6 MPa, and the reaction time was 3 h. When the softening point of the material reached 45°C, the reaction was stopped to obtain product III.

[0042] The kettle residue with a temperature greater than 500°C was added to the reactor, and air was introduced during stirring at a stirring speed of 150 r / min, a reaction temperature of 200°C, and an air flow rate of 13 L / min. After a reaction time of 2 h, when the softening point of the material reached 45°C, the reaction was stopped to obtain product IV.

[0043] Mix Product I, Product II, Product III and Product IV according to a mass ratio of 18:35:15:32, with a stirring speed of 300 r / min, a stirring temperature of 180 °C, and a stirring time of 1.5 h to obtain a road asphalt material. The components and their ratios after slurry separation are shown in Table 1 below.

[0044] Example 3

[0045] Take 6 kg of catalytic slurry (the same as in Example 1), perform distillation through a vacuum distillation process with a vacuum degree of 3.2 mbar, and conduct cutting to obtain light components at room temperature to 350 °C, middle components at 350 °C to 420 °C, heavy components at 420 °C to 500 °C, and still residues above 500 °C.

[0046] Add the light components at room temperature to 350 °C and boron trifluoride / hydrofluoric acid catalyst into the reaction kettle and stir for reaction. The mass ratio of the light components to the catalyst is 1:3, and the mass ratio of boron trifluoride to hydrofluoric acid is 0.25:3. The stirring speed is 150 r / min, the reaction temperature is 180 °C, the reaction pressure is 1.5 MPa, and the reaction time is 1 h. Then, under the condition that the stirring speed and reaction pressure remain unchanged, adjust the reaction temperature to 220 °C and continue the reaction for 3 h. When the softening point of the material reaches 35 °C, stop the reaction to obtain Product I.

[0047] Add the middle components at 350 °C to 420 °C and carbon disulfide cross-linking agent into the reaction kettle and stir for reaction. The mass ratio of the middle components to the catalyst is 20:1. After purging with nitrogen, seal the reaction kettle and conduct the reaction during stirring. The stirring speed is 150 r / min, the reaction temperature is 280 °C, the reaction pressure is 1.2 MPa, and the reaction time is 8 h. Then, under the condition that the stirring speed and reaction pressure remain unchanged, adjust the reaction temperature to 400 °C and continue the reaction for 0.5 h. When the softening point of the material reaches 80 °C, stop the reaction to obtain Product II.

[0048] Add the heavy components at 420 °C to 500 °C and boron trifluoride / hydrofluoric acid catalyst into the reaction kettle and stir for reaction during the sealing process. The mass ratio of the heavy components to the catalyst is 1:5, and the mass ratio of boron trifluoride to hydrofluoric acid is 0.5:3. The stirring speed is 150 r / min, the reaction temperature is 260 °C, the reaction pressure is 1.5 MPa, and the reaction time is 1.5 h. When the softening point of the material reaches 45 °C, stop the reaction to obtain Product III.

[0049] Add the still residues above 500 °C into the reaction kettle, introduce air during stirring, with a stirring speed of 150 r / min, a reaction temperature of 160 °C, an air flow rate of 6 L / min, and a reaction time of 5 h. When the softening point of the material reaches 45 °C, stop the reaction to obtain Product IV.

[0050] Stir and mix Product I, Product II, Product III, and Product IV in a mass ratio of 13:42:19:26 at a stirring speed of 300 r / min, a stirring temperature of 180 °C, and a stirring time of 1.5 h to obtain a road asphalt material. The components and ratios after slurry separation are shown in Table 1 below.

[0051] Comparative Example 1

[0052] Take 6 kg of catalytic slurry (the same as in Example 1), perform distillation through a vacuum distillation process with a vacuum degree of 3.2 mbar, and conduct cutting to obtain light components at room temperature to 350 °C, middle components at 350 °C to 420 °C, heavy components at 420 °C to 500 °C, and still residue above 500 °C.

[0053] Add the light components at room temperature to 350 °C to a reaction kettle and stir for reaction at a stirring speed of 150 r / min, a reaction temperature of 150 °C, a reaction pressure of 1.2 MPa, and a reaction time of 2 h. Then, under the conditions of unchanged stirring speed and reaction pressure, adjust the reaction temperature to 200 °C and continue the reaction for another 2 h, and then stop the reaction to obtain Product I.

[0054] Add the middle components at 350 °C to 420 °C to a reaction kettle and stir for reaction. After purging with nitrogen, seal the reaction kettle and conduct the reaction during stirring at a stirring speed of 150 r / min, a reaction temperature of 300 °C, a reaction pressure of 1.0 MPa, and a reaction time of 5 h. Then, under the conditions of unchanged stirring speed and reaction pressure, adjust the reaction temperature to 380 °C and continue the reaction for 1 h, and then stop the reaction to obtain Product II.

[0055] Add the heavy components at 420 °C to 500 °C to a reaction kettle and conduct stirring reaction during sealing at a stirring speed of 150 r / min, a reaction temperature of 200 °C, a reaction pressure of 1.8 MPa, and a reaction time of 2 h, and then stop the reaction to obtain Product III.

[0056] Add the still residue above 500 °C to a reaction kettle, introduce air during stirring at a stirring speed of 150 r / min, a reaction temperature of 180 °C, an air flow rate of 8 L / min. After 3 h of reaction, when the softening point of the material reaches 45 °C, stop the reaction to obtain Product IV.

[0057] Stir and mix Product I, Product II, Product III, and Product IV in a mass ratio of 20:32:18:30 at a stirring speed of 300 r / min, a stirring temperature of 180 °C, and a stirring time of 1.5 h to obtain a road asphalt material. The raw material names and ratios of the road asphalt material are shown in Table 2 below.

[0058] Comparative Example 2

[0059] Take 6 kg of catalytic slurry (same as in Example 1), distill it through a vacuum distillation process with a vacuum degree of 3.2 mbar, and perform cutting to obtain light components at room temperature to 350 °C, middle components at 350 °C to 420 °C, heavy components at 420 °C to 500 °C, and still residues above 500 °C respectively.

[0060] Add the light components at room temperature to 350 °C to the reaction kettle and stir for reaction. The stirring speed is 150 r / min, the reaction temperature is 160 °C, the reaction pressure is 1.0 MPa, and the reaction time is 1.5 h. Then, under the condition that the stirring speed and reaction pressure remain unchanged, adjust the reaction temperature to 250 °C and continue the reaction for 1 h. Stop the reaction to obtain Product I.

[0061] Add the middle components at 350 °C to 42 °C and the elemental sulfur cross-linking agent to the reaction kettle and stir for reaction. The mass ratio of the middle components to the catalyst is 20:5. After purging with nitrogen, seal the reaction kettle and carry out the reaction during stirring. The stirring speed is 150 r / min, the reaction temperature is 320 °C, the reaction pressure is 0.6 MPa, and the reaction time is 4 h. Then, under the condition that the stirring speed and reaction pressure remain unchanged, adjust the reaction temperature to 360 °C and continue the reaction for 1.5 h. When the softening point of the material reaches 80 °C, stop the reaction to obtain Product II.

[0062] Add the heavy components at 420 °C to 500 °C to the reaction kettle and carry out stirring reaction during the sealing process. The stirring speed is 150 r / min, the reaction temperature is 210 °C, the reaction pressure is 1.6 MPa, and the reaction time is 3 h. Stop the reaction to obtain Product III.

[0063] Add the still residues above 500 °C to the reaction kettle and introduce air during stirring. The stirring speed is 150 r / min, the reaction temperature is 200 °C, the air flow rate is 13 L / min. After 2 h of reaction, when the softening point of the material reaches 45 °C, stop the reaction to obtain Product IV.

[0064] Stir and mix Product I, Product II, Product III, and Product IV according to a mass ratio of 18:35:15:32. The stirring speed is 300 r / min, the stirring temperature is 180 °C, and the stirring time is 1.5 h to obtain a road asphalt material. The components and ratios after slurry separation are shown in Table 2 below.

[0065] Comparative Example 3

[0066] Take 6 kg of catalytic slurry (same as in Example 1), and distill it through a vacuum distillation process with a vacuum degree of 3.2 mbar. Conduct cutting to obtain light components at room temperature to 350 °C, middle components at 350 °C to 420 °C, heavy components at 420 °C to 500 °C, and still residues above 500 °C respectively.

[0067] Add the light components at room temperature to 350 °C and boron trifluoride / hydrofluoric acid catalyst into the reaction kettle and stir for reaction. The mass ratio of the light components to the catalyst is 1:3, the mass ratio of boron trifluoride to hydrofluoric acid is 0.25:3, the stirring speed is 150 r / min, the reaction temperature is 180 °C, the reaction pressure is 1.5 MPa, and the reaction time is 1 h. Then, under the condition that the stirring speed and reaction pressure remain unchanged, adjust the reaction temperature to 220 °C and continue the reaction for 3 h. When the softening point of the material reaches 35 °C, stop the reaction to obtain Product I.

[0068] Add the middle components at 350 °C to 420 °C into the reaction kettle and stir for reaction. After purging with nitrogen, seal the reaction kettle and conduct the reaction during stirring. The stirring speed is 150 r / min, the reaction temperature is 280 °C, the reaction pressure is 1.2 MPa, and the reaction time is 8 h. Then, under the condition that the stirring speed and reaction pressure remain unchanged, adjust the reaction temperature to 400 °C and continue the reaction for 0.5 h. Stop the reaction to obtain Product II.

[0069] Add the heavy components at 420 °C to 500 °C and boron trifluoride / hydrofluoric acid catalyst into the reaction kettle, and conduct stirring reaction during the sealing process. The mass ratio of the heavy components to the catalyst is 1:5, the mass ratio of boron trifluoride to hydrofluoric acid is 0.5:3, the stirring speed is 150 r / min, the reaction temperature is 260 °C, the reaction pressure is 1.5 MPa, and the reaction time is 1.5 h. When the softening point of the material reaches 45 °C, stop the reaction to obtain Product III.

[0070] Add the still residues above 500 °C into the reaction kettle, and introduce air during stirring. The stirring speed is 150 r / min, the reaction temperature is 160 °C, the air flow rate is 6 L / min, and after the reaction time of 5 h, when the softening point of the material reaches 45 °C, stop the reaction to obtain Product IV.

[0071] Stir and mix Product I, Product II, Product III, and Product IV according to the mass ratio of 13:42:19:26. The stirring speed is 300 r / min, the stirring temperature is 180 °C, and the stirring time is 1.5 h to obtain a road asphalt material. The components and ratios after the slurry separation are shown in Table 2 below.

[0072] Table 1 Components and mass ratios of each component after the catalytic slurry separation in each example

[0073] Material category Example 1 Example 2 Example 3 Light - component reactant / % 20 18 13 Medium - component reactant / % 32 35 42 Heavy - component reactant / % 18 15 19 Bottom residue reactant / % 30 32 26

[0074] Table 2 Components and mass ratios of each component after separation of catalytic slurry for each comparative ratio

[0075] Material category Comparative example 1 Comparative example 2 Comparative example 3 Light - component reactant / % 20 18 13 Medium - component reactant / % 32 35 42 Heavy - component reactant / % 18 15 19 Bottom residue reactant / % 30 32 26

[0076] The road asphalt materials prepared in Examples 1-3 and Comparative Examples 1-3 were tested with reference to some technical requirements of JTG F40-2004 "Technical Specifications for Construction of Highway Asphalt Pavements". The technical requirements are shown in Table 3 and the test results are shown in Table 4.

[0077] Table 3 Technical requirements

[0078]

[0079] Table 4 Properties of road asphalt materials

[0080]

[0081]

[0082] From the comparison results in Table 4, the main indicators of Examples 1-3 all meet the requirements of Class A road petroleum asphalt, and are significantly better than the performance of Comparative Examples 1-3.

Claims

1. A method for synthesizing road asphalt, comprising the following steps: (1) Fractionating catalytic slurry into four components: light fraction, middle fraction, heavy fraction, and still residue; (2) Reacting the light fraction and heavy fraction separated in step (1) with a catalyst respectively to obtain product I and product II, mixing the middle fraction separated in step (1) with a crosslinking agent for reaction to obtain product III; mixing the still residue of step (1) with an oxygen-containing gas for reaction to obtain product IV; (3) Blending product I, product II, product III, and product IV obtained in step (2) to obtain the road asphalt.

2. The method according to claim 1, characterized in that The catalytic slurry is a catalytic slurry produced by a catalytic cracking unit from natural petroleum and is a mixture rich in aromatics; the mass content of aromatics in the catalytic slurry is 50% - 90%, the mass content of paraffins in the catalytic slurry is less than 5%, and the mass content of naphthenes is less than 15%.

3. The method according to claim 1, wherein The slurry fractionation method in step (1) is carried out by vacuum distillation with a vacuum degree of 2 - 5 mbar; And / or, the cut-off point between the light fraction and the middle fraction in step (1) is 340°C - 360°C, the cut-off point between the middle fraction and the heavy fraction is 430°C - 450°C, and the cut-off point between the heavy fraction and the still residue is 510°C - 530°C.

4. The method according to claim 1, wherein The crosslinking agent in step (2) is one or more of elemental sulfur, sulfur monochloride, carbon disulfide, thiazoles, thiurams, sulfenamides, guanidines, dithiocarbamates, aldehyde amines, xanthates, thiourea, and isocyanates, preferably elemental sulfur or carbon disulfide.

5. The method according to claim 1, wherein The catalyst in step (2) is one or more of boron halogen compounds and halogen acids, preferably hydrofluoric acid, boron trifluoride, or boron trifluoride / hydrofluoric acid.

6. The method according to claim 1, wherein In step (2), the light fraction in step (1) is reacted under the action of a catalyst, and the mass ratio of the light fraction to the catalyst is (1 - 2):(2 - 3); And / or, in step (2), the light fraction and the catalyst in step (1) are added to a reaction kettle, and stirring reaction is carried out during the sealing process. The stirring speed of the reaction kettle is 100 r / min - 200 r / min, the reaction temperature is 150°C - 180°C, the reaction pressure is 1.0 MPa - 1.5 MPa, and the reaction time is 1 h - 3 h. Then, under the conditions of unchanged stirring speed and reaction pressure, the reaction temperature is adjusted to 200°C - 260°C, and the reaction is carried out for another 1 h - 3 h. When the softening point of the material reaches 32 - 38°C, the reaction is stopped to obtain product I.

7. The method according to claim 1, characterized in that, In step (2), the middle fraction in step (1) is reacted under the action of a crosslinking agent, and the mass ratio of the middle fraction to the crosslinking agent is (10 - 20):(1 - 5); And / or, in step (2), the medium component and the crosslinking agent in step (1) are added to a reaction kettle, and after purging with nitrogen, the reaction kettle is sealed and the reaction is carried out during stirring. The stirring speed of the reaction kettle is 100 r / min to 200 r / min, the reaction temperature is 280 °C to 320 °C, the reaction pressure is 0.5 MPa to 1.2 MPa, and the reaction time is 3 h to 8 h. Then, under the condition that the stirring speed and the reaction pressure remain unchanged, the reaction temperature is adjusted to 360 °C to 400 °C, and the reaction is carried out for another 0.1 h to 2 h. When the softening point of the material reaches 77 to 83 °C, the reaction is stopped to obtain Product II.

8. The method according to claim 1, characterized in that, In step (2), the heavy component in step (1) is reacted under the action of a catalyst, and the mass ratio of the heavy component to the catalyst is (1 to 2):(3 to 5); And / or, in step (2), the heavy component and the catalyst in step (1) are added to a reaction kettle, and a stirring reaction is carried out during the sealing process. The stirring speed of the reaction kettle is 100 r / min to 200 r / min, the reaction temperature is 200 °C to 260 °C, the reaction pressure is 1.5 MPa to 2.0 MPa, and the reaction time is 1 h to 5 h. When the softening point of the material reaches 42 to 48 °C, the reaction is stopped to obtain Product III.

9. The method according to claim 1, characterized in that, In step (2), the kettle residue in step (1) is added to a reaction kettle, and an oxygen-containing gas is introduced during stirring; the stirring speed of the reaction kettle is 100 r / min to 200 r / min, the reaction temperature is 150 °C to 200 °C, the flow rate of the oxygen-containing gas is 6 to 15 L / min. After the reaction time of 2 h to 5 h, when the softening point of the material reaches 42 to 48 °C, the reaction is stopped to obtain Product IV; the oxygen-containing gas is preferably air.

10. The method according to claim 1, wherein In step (3), Product I, Product II, Product III, and Product IV obtained in step (2) are blended, the stirring speed is 200 r / min to 500 r / min, the stirring temperature is 170 °C to 200 °C, and the stirring time is 1 h to 2 h to obtain road asphalt; And / or, in step (3), the mass ratio of Product I, Product II, Product III, and Product IV obtained in step (2) is (10 to 20):(30 to 45):(10 to 20):(25 to 35).

11. A road asphalt obtained by the method according to any one of claims 1-10.

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