Hydrocarbon-based graphene modified asphalt and preparation method thereof

Abstract

The present invention relates to a hydrocarbon-based graphene modified asphalt and a preparation method thereof, the hydrocarbon-based graphene modified asphalt comprises, by mass, 98.0-99.9% of matrix asphalt and 0.1-2.0% of a modifier, and the modifier is hydrocarbon-based graphene prepared by using a petrochemical oil refining by-product heavy aromatic hydrocarbon as a raw material. The hydrocarbon-based graphene prepared by using the petrochemical oil refining byproduct heavy aromatics as the raw material is used as the modifier, so that the softening point and the viscosity of the asphalt can be effectively improved, the high-temperature performance of the asphalt is improved, and the economic value of the petrochemical byproduct is greatly improved; the preparation process is simple and easy to implement.

Description

Technical Field

[0001] The present invention relates to the technical field of asphalt, and in particular to a hydrocarbon-based graphene-modified asphalt and a preparation method thereof. Background Art

[0002] As an important part of the modern infrastructure system, the construction quality of transportation infrastructure is directly related to the overall economic development of the country. Asphalt pavement occupies an important position in the field of highway construction due to its many advantages such as good driving comfort, fast traffic opening after construction, and convenient maintenance and repair.

[0003] However, traditional petroleum asphalt tends to flow at high temperatures, crack at low temperatures, and age easily, which causes cracks, looseness, potholes and other defects in asphalt pavements, which seriously affect road safety and shorten their service life. In particular, climate warming has led to rising global temperatures, which has put forward higher requirements for the high-temperature performance of asphalt pavements, especially in areas with high temperatures all year round and continuous high temperatures in summer. Frequent maintenance of asphalt pavements causes direct or indirect economic losses. Therefore, the performance of existing asphalt pavement materials needs to be further improved to meet the increasingly harsh service environment application requirements.

[0004] At present, SBS modified asphalt and rubber powder modified asphalt, as typical representatives of polymer modified asphalt, have been widely used in high-grade asphalt pavement construction and achieved good results. However, SBS modified asphalt has high cost, poor compatibility between rubber powder and asphalt, and produces a lot of smoke. Nanomaterials provide a new idea for asphalt modification. Graphene, as a nanomaterial, has become an important technical means to improve the performance of asphalt materials and inhibit asphalt smoke.

[0005] Chinese patent CN115093713A "A graphene-modified asphalt and its preparation method" uses graphene, styrene-butadiene-styrene block copolymer, polyurethane and rubber as modifiers to prepare modified asphalt, improving the aging resistance, fatigue resistance and hydrophobicity of asphalt. However, the materials used in this material system are relatively complex, and the amount of modifier used is relatively large, resulting in excessively high costs for the material system, and it is easy to cause material incompatibility and lead to segregation. Chinese patent CN112480695A "A method for preparing graphene-modified asphalt and its product" uses polyethylene glycol / titanium dioxide / polyurethane modified graphene composite materials as modifiers, uses polyurethane to modify graphene, improves its dispersibility in asphalt, and combines polyethylene glycol and titanium dioxide to improve the thermal stability of asphalt; however, this material system and preparation process are complex and difficult to implement. Summary of the invention

[0006] The purpose of the present invention is to overcome the above technical deficiencies, provide a hydrocarbon-based graphene-modified asphalt and a preparation method thereof, and solve the technical problems of high cost or complex process of asphalt modification in the prior art.

[0007] In order to achieve the above technical purpose, the technical solution provided by the present invention is: In a first aspect, the present invention provides a hydrocarbon-based graphene-modified asphalt, which is composed of 98.0% to 99.9% of a base asphalt and 0.1% to 2.0% of a modifier, measured by mass percentage, wherein the modifier is a hydrocarbon-based graphene prepared using heavy aromatic hydrocarbons, a by-product of petrochemical refining, as raw materials.

[0008] In a second aspect, the present invention provides a method for preparing hydrocarbon-based graphene-modified asphalt, comprising the following steps: (1) premixing a modifier with a base asphalt heated to a fluid state to obtain a premix; and (2) shearing and heat-insulating the premix to obtain a hydrocarbon-based graphene-modified asphalt.

[0009] Compared with the prior art, the beneficial effects of the present invention include: The present invention uses hydrocarbon-based graphene prepared from heavy aromatic hydrocarbons, a by-product of petrochemical refining, as a raw material as a modifier, and can achieve modification of asphalt at a relatively low dosage, with low cost and good compatibility with asphalt. It can effectively improve the softening point and viscosity of asphalt, improve the high-temperature performance of asphalt, reduce road surface diseases caused by high temperature, reduce safety hazards, extend the service life, reduce maintenance costs, and achieve high performance and green asphalt pavement materials; the method of the present invention can utilize a large amount of hydrocarbon-based graphene prepared from petrochemical by-products, greatly improve the economic value of petrochemical by-products, and reduce environmental pollution caused by petrochemical by-product processing and graphene preparation; the preparation process of the present invention is simple and easy to implement. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a schematic flow diagram of a method for preparing hydrocarbon-based graphene-modified asphalt of the present invention; Figure 2 It is a comparison of the softening points of the asphalts obtained in Comparative Examples 1-5 and Examples 1-4 of the present invention; Figure 3 It is a comparison of the viscosity of the asphalt obtained in Comparative Examples 1-5 and Examples 1-4 of the present invention; Figure 4 It is a comparison of the high temperature composite modulus of the asphalt obtained in Comparative Example 1, Comparative Example 5 and Example 4 of the present invention; Figure 5 It is a comparison of the high temperature phase angles of the asphalts obtained in Comparative Example 1, Comparative Example 5 and Example 4 of the present invention. DETAILED DESCRIPTION

[0011] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0012] At present, graphene is often used in asphalt modification, but traditional graphite-based graphene is expensive and the market supply is insufficient, which cannot meet the application needs of bulk asphalt materials. The petrochemical industry is developing rapidly, and petrochemical by-products are increasing, but their comprehensive utilization rate is low. The hydrocarbon-based graphene prepared from petrochemical by-products has low production costs and can be mass-produced, but has not yet been applied in asphalt materials. In view of the above problems, the present invention provides a hydrocarbon-based graphene modified asphalt suitable for high temperature areas and a preparation method, and uses hydrocarbon-based graphene as a modifier to prepare a modified asphalt suitable for high temperature areas.

[0013] In a first aspect, the present invention provides a hydrocarbon-based graphene-modified asphalt, which is composed of 98.0% to 99.9% of a base asphalt and 0.1% to 2.0% of a modifier, measured by mass percentage, wherein the modifier is a hydrocarbon-based graphene prepared using heavy aromatic hydrocarbons, a by-product of petrochemical refining, as raw materials.

[0014] Since modifiers generally have compatibility issues with asphalt, too much modifier will lead to segregation, which will deteriorate the performance of the modified asphalt and increase the cost; too little modifier will not play a modifying role, so the present invention preferably adds 0.5% to 2.0% of the modifier.

[0015] Preferably, the base asphalt includes No. 70 road petroleum asphalt and meets the technical requirements for asphalt in the "Technical Specifications for Highway Asphalt Pavement Construction".

[0016] Preferably, the particle size of the hydrocarbon-based graphene is 0.03 μm to 104 μm.

[0017] Preferably, the preparation steps of hydrocarbon-based graphene include: mixing heavy aromatic hydrocarbons, a by-product of petrochemical refining, and a carbonizing agent, heating to 150°C to 220°C for reaction for 4h to 24h, cooling to room temperature and filtering, washing and drying the obtained filter cake to obtain a graphene precursor; mixing the graphene precursor with a filler and grinding them evenly, and treating the obtained mixture powder at 600°C to 1200°C for 2h to 20h under inert gas protection to obtain hydrocarbon-based graphene.

[0018] Further preferably, the content of heavy aromatics in the petrochemical refining by-product heavy aromatics is above 80%; the carbonizing agent is 70% to 98% sulfuric acid; and the volume ratio of the petrochemical refining by-product heavy aromatics to the carbonizing agent is 1:(0.5 to 2).

[0019] Further preferably, the weight ratio of the graphene precursor to the filler is 1:(5-100); the filler is selected from MgCl 2 , KCl, K 2 CO 3 and CaCO 3or the filler is selected from one of the mixed salts, the mixed salts include NaCl / KCl, KCl / LiCl, NaF / CaF 2 / MgCl 2 or NaCl / KCl / ZnCl 2 .

[0020] In a second aspect, the present invention provides a method for preparing hydrocarbon-based graphene-modified asphalt, see Figure 1 , including the following steps: (1) premixing the modifier with the base asphalt heated to a fluid state to obtain a premix; (2) The premix is ​​sheared and heat-treated to obtain hydrocarbon-based graphene-modified asphalt.

[0021] Preferably, in step (2), the shearing conditions are: the temperature is 140°C to 150°C, the shearing speed is first 1600 r / min to 2400 r / min for 15 min to 25 min, then the shearing speed is 2600 r / min to 3400 r / min for 25 min to 35 min, and finally the shearing speed is 4500 r / min to 5500 r / min for 5 min to 15 min.

[0022] Preferably, in step (2), the temperature of the heat preservation development is 140° C. to 150° C., and the time is 0.5 h to 1.0 h.

[0023] The present invention first heats the base asphalt to a fluid state so that it can be better mixed with the modifier; and shearing and development are performed under heat preservation conditions to maintain good fluidity of the asphalt and meet the shearing requirements. At the same time, the temperature is set at 140°C to 150°C to avoid asphalt aging due to excessive temperature. By controlling the shearing speed and shearing time, the base asphalt and the modifier are mixed evenly; by controlling the heat preservation and development time, the prepared sample reaches a balanced state.

[0024] The present invention also has the following advantages: (1) The preparation process of the method of the present invention is simple and easy to implement.

[0025] (2) The method of the present invention can obtain a hydrocarbon-based graphene-modified asphalt, which can reduce pavement damage caused by high temperature, reduce safety hazards, extend the service life, reduce maintenance costs, and achieve high performance and green asphalt pavement materials.

[0026] (3) The method of the present invention can make large-scale use of hydrocarbon-based graphene prepared from petrochemical by-products, greatly improve the economic value of petrochemical by-products, and reduce environmental pollution caused by petrochemical by-product processing and graphene preparation.

[0027] The present invention is further described in detail below through specific examples and comparative examples.

[0028] Example 1 A method for preparing hydrocarbon-based graphene-modified asphalt comprises the following steps: (1) According to the mass percentage of each raw material: base asphalt 99.5%, modifier 0.5%, take the base asphalt and modifier for later use; Among them, the base asphalt refers to the petroleum asphalt of Road No. 70, and it meets the technical requirements for asphalt in the "Technical Specifications for Highway Asphalt Pavement Construction"; The modifier refers to hydrocarbon-based graphene, and the specific preparation steps are: (101) Take 30 mL of heavy aromatic hydrocarbons (wherein the content of heavy aromatic hydrocarbons is above 80%), slowly add 30 mL of concentrated sulfuric acid (concentration is 98%), heat to 180 °C for 4 h, cool to room temperature, filter the reaction solution, wash repeatedly, and dry to obtain a graphene precursor; (102) The graphene precursor obtained in the above step is mixed with filler KCl / LiCl (mass ratio, 1:1) in a mass ratio of 1:10, and ground into a uniform fine powder; the obtained mixture powder is subjected to high temperature treatment at a heating rate of 5°C / min to 800°C under the protection of an inert gas argon, and maintained for 2 h. After cooling, it is washed and dried to obtain hydrocarbon-based graphene.

[0029] (2) The base asphalt is heated to a fluid state and premixed with the modifier to obtain a premix.

[0030] (3) The premix is ​​sheared and heat-treated, wherein the shear temperature is 150°C, the shear speed and time are 2000 r / min for shearing for 20 min, 3000 r / min for shearing for 30 min, and 5000 r / min for shearing for 10 min; the heat-treatment time conditions are: temperature is 150°C, time is 0.5 h; and hydrocarbon-based graphene-modified asphalt is obtained.

[0031] Example 2 The only difference from Example 1 is that the amount of base asphalt added is adjusted to 99%, the amount of modifier added is adjusted to 1.0%, and other conditions are the same as Example 1.

[0032] Example 3 The only difference from Example 1 is that the amount of base asphalt added is adjusted to 98.5%, the amount of modifier added is adjusted to 1.5%, and other conditions are the same as Example 1.

[0033] Example 4 The only difference from Example 1 is that the amount of base asphalt added is adjusted to 98%, the amount of modifier added is adjusted to 2.0%, and other conditions are the same as Example 1.

[0034] Comparative Example 1 The only difference from Example 1 is that no modifier is added, the base asphalt addition amount is 100%, and other conditions are the same as Example 1.

[0035] Comparative Example 2 The only difference from Example 1 is that the modifier is changed to ordinary graphene, and other conditions are the same as Example 1.

[0036] Comparative Example 3 The only difference from Example 2 is that the modifier is changed to ordinary graphene, and other conditions are the same as Example 2.

[0037] Comparative Example 4 The only difference from Example 3 is that the modifier is changed to ordinary graphene, and other conditions are the same as Example 3.

[0038] Comparative Example 5 The only difference from Example 4 is that the modifier is changed to ordinary graphene, and other conditions are the same as Example 4.

[0039] Performance Testing Referring to the interpretation manual of JTG E20-2011 "Test Procedures for Asphalt and Asphalt Mixtures for Highway Engineering", the softening point, viscosity, and DSR high temperature rheological properties of Examples 1-4 and Comparative Examples 1-5 were tested respectively, and the effects of different amounts of modifiers on asphalt properties were compared. The experimental results are as follows: Figure 2 , Figure 3 , Figure 4 and Figure 5 shown.

[0040] Depend on Figure 2 , Figure 3 The test results show that with the addition of graphene, the softening point and viscosity of Examples 1-4 and Comparative Examples 2-5 are higher than that of Comparative Example 1 (without any type of graphene), and the degree of increase in the softening point and viscosity of Examples 1-4 is higher than that of Comparative Examples 2-5 in the same group. This shows that the incorporation of hydrocarbon-based graphene in the present invention can effectively increase the softening point and viscosity of asphalt, improve the high-temperature performance of asphalt, and the effect of hydrocarbon-based graphene is better than that of ordinary graphene.

[0041] Figure 4 and Figure 5 It shows that the addition of graphene in the embodiment increases the high-temperature composite modulus of asphalt and reduces the phase angle relative to the comparative example 1 without adding graphene, both showing that the addition of graphene can improve the high-temperature performance of asphalt, and the composite modulus of embodiment 4 is higher than that of comparative example 5, and the phase angle of embodiment 4 is smaller than that of comparative example 5, which also proves that the effect of hydrocarbon-based graphene in improving the high-temperature performance of asphalt is better than that of ordinary graphene.

[0042] The present invention provides a hydrocarbon-based graphene modified asphalt and a preparation method thereof. The modified asphalt is composed of a base asphalt and a modifier, and the mass percentage of each raw material is: 98.0% to 99.9% of the base asphalt and 0.1% to 2.0% of the modifier. The base asphalt is No. 70 road petroleum asphalt, and the modifier is hydrocarbon-based graphene. The hydrocarbon-based graphene used in the present invention is prepared from petrochemical by-products, and the prepared hydrocarbon-based graphene modified asphalt has good high-temperature performance, reduces road surface diseases caused by high temperature, reduces safety hazards, prolongs service life, reduces maintenance costs, and realizes high performance and greening of asphalt pavement materials.

[0043] The specific implementation of the present invention described above does not constitute a limitation on the protection scope of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A hydrocarbon-based graphene-modified asphalt, characterized in that: By mass percentage, it is composed of 98.0% to 99.9% of base asphalt and 0.1% to 2.0% of modifier; The modifier is a hydrocarbon-based graphene prepared by taking heavy aromatic hydrocarbons, a by-product of petrochemical refining, as a raw material.

2. The hydrocarbon-based graphene-modified asphalt according to claim 1, characterized in that: The base asphalt includes Route 70 road petroleum asphalt.

3. The hydrocarbon-based graphene-modified asphalt according to claim 1, characterized in that: The particle size of the hydrocarbon-based graphene is 0.03 μm to 104 μm.

4. The hydrocarbon-based graphene-modified asphalt according to claim 1, characterized in that: The preparation steps of the hydrocarbon-based graphene include: The heavy aromatic hydrocarbons produced as a byproduct of petrochemical refining and a carbonizing agent are mixed, heated to 150°C to 220°C for reaction for 4h to 24h, cooled to room temperature and filtered, and the obtained filter cake is washed and dried to obtain a graphene precursor; The graphene precursor and the filler are mixed and ground evenly, and the obtained mixture powder is treated at 600° C. to 1200° C. for 2 h to 20 h under the protection of an inert gas to obtain hydrocarbon-based graphene.

5. The hydrocarbon-based graphene-modified asphalt according to claim 4, characterized in that: The content of heavy aromatics in the petrochemical refining by-product heavy aromatics is above 80%; The carbonizing agent is 70% to 98% sulfuric acid; The volume ratio of the petrochemical refining by-product heavy aromatics to the carbonizing agent is 1: (0.5-2).

6. The hydrocarbon-based graphene-modified asphalt according to claim 4, characterized in that: The weight ratio of the graphene precursor to the filler is 1:(5-100).

7. The hydrocarbon-based graphene-modified asphalt according to claim 4, characterized in that: The filler is selected from one of MgCl2, KCl, K2CO3 and CaCO3; Or the filler is selected from one of the mixed salts, and the mixed salt includes NaCl / KCl, KCl / LiCl, NaF / CaF2 / MgCl2 or NaCl / KCl / ZnCl2.

8. The method for preparing the hydrocarbon-based graphene-modified asphalt according to any one of claims 1 to 7, characterized in that: The steps include: (1) premixing the modifier with the base asphalt heated to a fluid state to obtain a premix; (2) The premix is ​​sheared and heat-treated to obtain hydrocarbon-based graphene-modified asphalt.

9. The method for preparing hydrocarbon-based graphene-modified asphalt according to claim 8, characterized in that: In step (2), the shearing conditions are: the temperature is 140°C to 150°C, the shearing speed is first 1600 r / min to 2400 r / min for 15 min to 25 min, the shearing speed is then 2600 r / min to 3400 r / min for 25 min to 35 min, and finally the shearing speed is 4500 r / min to 5500 r / min for 5 min to 15 min.

10. The method for preparing hydrocarbon-based graphene-modified asphalt according to claim 8, characterized in that: In step (2), the temperature of the heat preservation development is 140°C to 150°C, and the time is 0.5h to 1.0h.

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