RAP asphalt regenerant with high utilization rate and preparation method of RAP asphalt regenerant

Abstract

The invention relates to a high-utilization-rate RAP asphalt regenerant and a preparation method thereof. The regenerant comprises the following components in percentage by mass: 30%-50% of a petroleum-based softener, 10%-20% of biomass oil, 5%-15% of a polymer modifier, 1%-5% of a surfactant, 0.5%-2% of an antioxidant and 2%-10% of a functional additive. All the components have a synergistic effect, so that the asphalt modifier can effectively permeate aged asphalt, supplement light oil, reduce viscosity, recover flexibility and remarkably improve high-temperature rut resistance and low-temperature crack resistance of regenerated asphalt. By reasonably selecting the raw materials and proportioning, the production cost is reduced, the RAP utilization rate is improved, and the environment-friendly raw materials are adopted, so that the requirements of environmental regulations are met. The result of the embodiment shows that after the regenerant is added, the performance recovery of the aged asphalt is good, the viscosity of the regenerated asphalt mixture is moderate, the needle penetration recovery rate is high, the softening point is high, the ductility is large, the comprehensive performance is excellent, and the regenerant is superior to commercially available products.

Description

Technical Field

[0001] The present invention relates to the technical field of road engineering materials, and in particular to a high-utilization-rate RAP (recycled asphalt pavement material) asphalt regeneration agent and a preparation method thereof. Background Art

[0002] With the rapid development of my country's transportation industry, a large number of asphalt pavements are facing renovation and reconstruction. This repair and renovation of asphalt pavements has generated a large amount of recycled asphalt pavement material (RAP). The emergence of RAP provides a solution to the problems of resource waste and environmental pollution. However, the performance of aged asphalt in RAP is poor, requiring asphalt regeneration agents to restore its performance. Asphalt regeneration agents currently on the market have many shortcomings, such as unsatisfactory regeneration results and inability to fully restore the performance of aged asphalt; some regeneration agents have complex formulations and high costs; and some regeneration agents are poorly compatible with RAP, affecting the quality and stability of the regenerated asphalt.

[0003] Patent document CN202110771607.X discloses an asphalt regeneration agent and its production method. The agent comprises the following raw materials: a softener, a tackifier, a modifier, heavy oil, a petroleum resin, and a stabilizer. The weight percentages of each component are as follows: 30-40 parts softener; 10-15 parts tackifier; 20-28 parts modifier; 20-60 parts heavy oil; 3-5 parts petroleum resin; and 0.5-1 part stabilizer. However, ingredients such as the softener and heavy oil in this formulation may contain hazardous substances. During production and use, pollutants such as volatile organic compounds (VOCs) may be generated. This does not comply with current stringent environmental regulations and poses a potential hazard to the environment and the health of construction workers.

[0004] Patent document CN202311546092.9 discloses a biomimetic, environmentally friendly warm-mix regeneration agent comprising the following components by weight: 35-50 parts base oil, 15-20 parts extracted oil, 8-15 parts rubber oil, 5-15 parts homemade biomimetic mussel glue, and 5-8 parts antioxidant, for a total of 100 parts. The homemade biomimetic mussel glue is synthesized from oxetane derivatives and includes components A and B. However, the production process is complex and difficult to control. Furthermore, the high price of homemade biomimetic mussel glue hinders its widespread application.

[0005] Patent document CN202311186438.9 discloses a composite, high-efficiency asphalt rejuvenator with a high RAP dosage. The agent comprises the following components by weight: 70-90 parts composite base oil, 12-26 parts plasticizer, 2-6 parts low-temperature stabilizer, and 0.5-3 parts penetrant. However, the raw asphalt mixture suffers from insufficient low-temperature performance and storage stability, and is prone to aging, failing to meet application requirements.

[0006] Therefore, the development of a high-utilization RAP asphalt regeneration agent has important practical significance. Summary of the Invention

[0007] The purpose of the present invention is to provide a high-utilization RAP asphalt regeneration agent and a preparation method thereof, which can effectively restore the performance of aged asphalt, improve the utilization rate of RAP, reduce production costs, and have good environmental performance.

[0008] In order to achieve the above object, the present invention provides a high-utilization RAP asphalt regeneration agent, which comprises the following components by mass percentage:

[0009] Petroleum-based softener 30% to 50%,

[0010] Biomass oil 10% to 20%,

[0011] Polymer modifier 5% to 15%,

[0012] Surfactant 1% to 5%,

[0013] Antioxidants 0.5% to 2%,

[0014] Functional additives 2% to 10%.

[0015] Furthermore, the petroleum-based softener is selected from at least one of aromatic oil, naphthenic oil, mineral oil or catalytic cracking slurry.

[0016] Aromatic oil has excellent solubility and compatibility, allowing it to quickly penetrate the internal structure of aged asphalt. Its molecular structure is similar to certain components in aged asphalt. Based on the principle of like dissolves like, aromatic oil can be well dispersed in aged asphalt, replenishing the light oil lost due to aging. Furthermore, the addition of aromatic oil can effectively reduce asphalt viscosity by weakening the interactions between asphalt molecules, allowing them to slide more easily relative to each other. Furthermore, aromatic oil can significantly restore asphalt's flexibility, improving its ability to deform in low-temperature environments and reducing the likelihood of cracks in the pavement at low temperatures.

[0017] The cyclic structure of naphthenic oil imparts excellent flexibility and low-temperature performance. When penetrating aged asphalt, it leverages its structural characteristics to penetrate deep into the asphalt, replenishing the asphalt with lightweight oils. Naphthenic oil effectively reduces asphalt viscosity, improving its fluidity and facilitating handling during construction. Naphthenic oil also excels at restoring asphalt's flexibility. It enhances asphalt's elasticity, allowing it to deform more effectively without cracking under external forces, thereby improving the fatigue resistance of asphalt pavements.

[0018] Mineral oil is widely available and relatively inexpensive. It evenly penetrates aged asphalt, replenishing lost light oils and improving its composition. Its low viscosity helps reduce the overall viscosity of aged asphalt, improving its workability. Furthermore, mineral oil can restore asphalt's flexibility and improve its ductility, allowing asphalt pavements to better adapt to deformation under repeated vehicle loads and extending their service life.

[0019] Catalytic cracking slurry is rich in aromatics and olefins and possesses high activity. When penetrating aged asphalt, these active components react with certain substances within the asphalt, promoting molecular structural adjustments and more effectively replenishing light oils. Catalytic cracking slurry significantly reduces asphalt viscosity, improving its fluidity and significantly restoring its flexibility. It enhances asphalt toughness, making asphalt pavement less prone to rutting at high temperatures and less prone to cracking at low temperatures, thereby improving the overall performance of the pavement.

[0020] Furthermore, the biomass oil is at least one of castor oil, tall oil or palm oil. These three biomass oils are all derived from natural, renewable biological resources. Castor oil is extracted from castor seeds, tall oil is a by-product of the wood pulp and paper industry, and palm oil is obtained from palm fruits. Compared with traditional petroleum-based products, its production process has a low dependence on non-renewable resources, reducing the pressure on resource extraction. Moreover, during use, if the biomass oil leaks or remains, it can be quickly decomposed by microorganisms in the natural environment, reducing the risk of pollution to soil, water bodies, etc., which is in line with the concepts of sustainable development and environmental protection. The molecular structures of castor oil, tall oil and palm oil contain a variety of polar groups and unsaturated bonds. These special structures enable them to form good interactions with different components in asphalt. Polar groups can attract polar substances in asphalt, and unsaturated bonds can participate in some chemical reactions or physical entanglements within the asphalt, thereby enhancing the compatibility between the regeneration agent and asphalt, making the regeneration agent more evenly dispersed in the asphalt system, and improving the stability and performance uniformity of the regenerated asphalt.

[0021] Furthermore, the polymer modifier is at least one of SBS, SBR, or scrap tire rubber powder. At high temperatures, the rubber phase in the molecular structure of SBS (styrene-butadiene block copolymer) can restrict the flow of asphalt molecules, forming a network structure with high strength and elasticity, effectively resisting deformation caused by vehicle loads and reducing the formation of rutting. SBR (styrene-butadiene rubber) can also enhance the high-temperature stability of asphalt. It can fill the molecular gaps of asphalt, increase the cohesion and viscosity of asphalt, making it less likely to flow and deform at high temperatures, thereby improving the high-temperature rutting resistance of the recycled asphalt. Scrap tire rubber powder can also improve high-temperature performance. Its rubber particles act as a physical reinforcement in asphalt. In high-temperature environments, these particles can disperse stress, prevent excessive flow of asphalt, and thus improve the road surface's rutting resistance. In low-temperature environments, the elasticity of SBS can effectively alleviate stress concentration within the asphalt, preventing asphalt cracking caused by sudden temperature drops. It can enable asphalt to maintain a certain degree of flexibility and ductility at low temperatures, enhancing its crack resistance. SBR also has excellent low-temperature performance. It can lower the glass transition temperature of asphalt, making it less brittle at low temperatures, increasing the asphalt's flexibility and deformation capacity, and thus reducing the occurrence of low-temperature cracks. The rubber component in waste tire rubber powder can absorb energy at low temperatures, acting as a buffer, reducing the stress caused by shrinkage in the asphalt, and improving the low-temperature crack resistance of the recycled asphalt. Aging destroys the polymer network structure in asphalt. SBS can react with the polymers in aged asphalt through its own active groups to rebuild a stable network structure and restore the asphalt's performance. SBR can interact with the polymers in aged asphalt, filling defects and gaps in the network structure and enhancing the stability of the network. The rubber particles in waste tire rubber powder can entangle and fuse with the aged polymers in the asphalt, repairing the damaged network structure, improving the overall performance of the asphalt, and extending the service life of the asphalt pavement.

[0022] Furthermore, the surfactant is at least one of a fatty acid amide, an organosilicon compound, or a nonionic surfactant. Fatty acid amides have a unique molecular structure, with a lipophilic group at one end that tightly binds to aged asphalt molecules; and a hydrophilic group at the other end, which allows other components of the regeneration agent to better disperse within the aged asphalt, forming a stable dispersion. Organosilicon compounds, with their low surface tension, can quickly reduce the interfacial tension between the aged asphalt and the regeneration agent, allowing the regeneration agent to diffuse more easily and evenly within the aged asphalt, preventing agglomeration. Nonionic surfactants do not ionize in solution; their lipophilic groups can penetrate into the aged asphalt, while their hydrophilic groups extend outward. Through steric hindrance and electrostatic repulsion, these groups allow the regeneration agent to be stably dispersed within the aged asphalt, ensuring that all components are fully functional. Furthermore, fatty acid amides act as a bridge between the new and old asphalt. Their molecules interact with the different components in the new and old asphalt, strengthening their bond and promoting fusion. Organosilicon compounds can lower the surface energy at the interface between the new and old asphalt, making them more easily interpenetrable and diffusible, accelerating the fusion process and enhancing the fusion effect. Non-ionic surfactants can be adsorbed on the interface of new and old asphalt, reducing interfacial tension, increasing interfacial affinity, promoting rapid fusion of new and old asphalt, forming a uniform and stable system, improving the performance and stability of recycled asphalt, and ensuring the quality and life of the road.

[0023] Furthermore, the antioxidant is at least one of a hindered phenolic or amine antioxidant. These materials can delay secondary aging of regenerated asphalt and extend its service life. Hindered phenolic antioxidants include 2,6-di-tert-butyl-p-cresol (BHT), pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate (1010 antioxidant), and octadecyl β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate (1076 antioxidant).

[0024] Furthermore, the functional additives include a tackifier, a filler, and a regeneration catalyst; the tackifier is petroleum resin or Sichuan pepper resin, the filler is carbon black or nano-silica, and the regeneration catalyst is an organometallic salt. Petroleum resin or Sichuan pepper resin has excellent viscosity and compatibility, tightly binding to the various components in asphalt, increasing the cohesion between asphalt molecules and significantly improving the asphalt's bonding strength. Furthermore, at high temperatures, it helps raise the asphalt's softening point, enhancing its deformation resistance and reducing rutting. At low temperatures, it maintains asphalt's flexibility to a certain extent, lowers its brittle point, and improves the pavement's crack resistance. Carbon black, with its large specific surface area and excellent adsorption properties, can fill the voids in asphalt, increasing its density and hardness. This helps improve the wear resistance, compression resistance, and skid resistance of asphalt pavements, reducing wear and damage. Carbon black absorbs ultraviolet rays, reducing UV radiation damage to asphalt, thereby slowing the aging of asphalt. It also blocks oxygen and moisture intrusion to a certain extent, protecting the asphalt's internal structure and extending the pavement's service life. Carbon black also has high thermal conductivity, effectively conducting heat and maintaining relatively stable asphalt properties in high-temperature environments, reducing deformation and damage caused by temperature fluctuations. Nanosilica, with its extremely small particle size and large surface area, interacts strongly with asphalt molecules, enhancing asphalt's strength and toughness. When subjected to stress, nanosilica disperses stress, improving the asphalt pavement's crack and fatigue resistance. Nanosilica also fills the asphalt's microscopic pores, reducing its permeability and preventing the intrusion of moisture and harmful chemicals, thereby enhancing the pavement's durability and corrosion resistance. Organic metal salts reduce the activation energy of the regeneration reaction, accelerating the breaking and reforming of chemical bonds in aged asphalt and promoting the fusion and regeneration of old and new asphalt. This makes the regeneration process more efficient, shortens regeneration time, and improves production efficiency. Through catalysis, organic metal salts can more fully restore the properties of aged asphalt, improving the quality and performance of the regenerated asphalt. Furthermore, because the catalyst accelerates the reaction, the reaction temperature and time can be appropriately reduced during the regeneration process, thereby reducing energy consumption, lowering production costs, and benefiting environmental protection. Preferably, the organic metal salt may be one or more of iron naphthenate, cobalt naphthenate, zinc naphthenate, iron acetylacetonate, cobalt acetylacetonate, and dibutyltin dilaurate.

[0025] Furthermore, the mass ratio of the tackifier, filler and regeneration catalyst is (2-4):(1-3):(1-2).

[0026] Tackifier (2-4 parts): If the ratio is less than 2 parts, the tackifying effect may be insignificant, resulting in insufficient adhesion between the asphalt and aggregate, and prone to problems such as loose pavement. Above 4 parts, the asphalt viscosity may be too high, increasing construction difficulty and affecting the asphalt's flexibility and low-temperature performance. Within this ratio range, the asphalt's bonding properties can be effectively improved, enhancing the adhesion between the asphalt and aggregate, and ensuring pavement stability.

[0027] Fillers (1-3 parts): Less than 1 part has limited reinforcing effect on asphalt, making it difficult to significantly improve mechanical properties. Exceeding 3 parts may make the asphalt mixture too viscous, affecting construction and workability, and may also reduce the toughness of the asphalt. Fillers such as carbon black and nano-silica can effectively enhance the mechanical properties of asphalt within this range, such as increasing hardness and wear resistance, while also improving its anti-aging properties.

[0028] Regeneration Catalyst (1-2 parts): If the amount is less than 1 part, the catalytic effect is poor, the regeneration reaction of aged asphalt is slow, and the regeneration effect is unsatisfactory. If the amount is more than 2 parts, although the reaction speed is accelerated, it may cause an overreaction, negatively affecting the performance of the regenerated asphalt and increasing costs. Within this ratio range, organometallic salt regeneration catalysts can effectively accelerate the regeneration reaction of aged asphalt, reduce the reaction temperature and time required, and improve production efficiency.

[0029] On the other hand, the present invention also provides a method for preparing the above-mentioned regeneration agent, comprising the following steps:

[0030] (a) mixing a petroleum-based softener and biomass oil at 60-80° C. and stirring for 10-20 minutes;

[0031] (b) adding a polymer modifier, a surfactant, and an antioxidant to the mixture of step (a) in sequence, raising the temperature to 100-120° C. and reacting for 30-60 minutes;

[0032] (c) Cooling the mixture from step (b) to 50-70° C., adding the functional additive and continuing to stir until uniform.

[0033] Furthermore, the stirring rate in step (a) is 500-800 rpm, and the heating rate in step (b) is 2-5° C. / min.

[0034] The various components of the asphalt regeneration agent of the present invention work synergistically to effectively penetrate aged asphalt, replenish light oil, reduce viscosity, restore flexibility, and significantly improve the high-temperature rutting resistance and low-temperature cracking resistance of the regenerated asphalt.

[0035] By rationally selecting raw materials and proportions, the production cost is reduced and the utilization rate of RAP is improved while ensuring the regeneration effect.

[0036] Using environmentally friendly raw materials, biomass oil is derived from natural renewable resources. The production process has low dependence on non-renewable resources. In addition, if it leaks or remains during use, it can be easily decomposed by microorganisms, reducing pollution to the environment and complying with environmental protection regulations. DETAILED DESCRIPTION

[0037] The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0038] It will be understood that when used in this specification and the appended claims, the term "comprising" indicates the presence of described features, integers, steps, operations, elements and / or components, but does not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or collections.

[0039] It should be further understood that the term "and / or" used in this specification and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items.

[0040] In addition, in the description of the present application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0041] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the present invention will be described below with reference to specific implementation methods.

[0042] Example 1

[0043] Formula: aromatic oil 40%, castor oil 15%, SBS 8%, fatty acid amide 1.5%, hindered phenol antioxidant (BHT) 1%, petroleum resin 3%, nano-silica 2%, iron naphthenate 1.5%.

[0044] Preparation method:

[0045] Aromatic oil and castor oil were stirred at 600 rpm at 70 °C for 15 min;

[0046] Add SBS, fatty acid amide and BHT, raise the temperature to 110°C at 3°C / min, and react for 40 minutes;

[0047] Cool to 60°C, add petroleum resin, carbon black and ferric naphthenate, and continue stirring for 30 minutes.

[0048] Example 2

[0049] Formula: aromatic oil 40%, castor oil 15%, SBS 8%, fatty acid amide 1.5%, hindered phenol antioxidant (BHT) 1%, petroleum resin 3%, nano-silica 2%, iron naphthenate 1.5%.

[0050] Preparation method:

[0051] Aromatic oil and castor oil were stirred at 600 rpm at 70 °C for 15 min;

[0052] Add SBS, fatty acid amide and BHT, raise the temperature to 110°C at 3°C / min, and react for 40 minutes;

[0053] Cool down to 60℃, add petroleum resin, nano-silica and iron naphthenate, and continue stirring for 30 minutes.

[0054] Example 3

[0055] Formula: 40% naphthenic oil, 15% tall oil, 8% waste tire rubber powder, 1.5% organosilicon compound, 1% hindered phenol antioxidant (BHT), 3% petroleum resin, 2% nano-silica, 1.5% iron naphthenate.

[0056] Preparation method:

[0057] The naphthenic oil and tall oil were stirred at 70°C and 600 rpm for 20 minutes;

[0058] Add waste tire rubber powder, organosilicon compound and BHT, heat to 110℃ at 3℃ / min, and react for 40 minutes;

[0059] Cool down to 60℃, add petroleum resin, nano-silica and iron naphthenate, and stir for 30 minutes.

[0060] Comparative Example 1

[0061] Compared with Example 1, the difference of this comparative example is that the biomass oil castor oil is not contained, and other conditions are consistent with Example 1.

[0062] Comparative Example 2

[0063] Compared with Example 1, the difference of this comparative example is that the polymer modifier SBS is not contained, and other conditions are consistent with Example 1.

[0064] Comparative Example 3

[0065] Compared with Example 1, the difference of this comparative example is that the surfactant fatty acid amide is not contained, and other conditions are consistent with Example 1.

[0066] Comparative Example 4

[0067] Compared with Example 1, the difference of this comparative example is that the tackifier petroleum resin is not contained, and other conditions are consistent with Example 1.

[0068] Comparative Example 5

[0069] Compared with Example 1, the difference of this comparative example is that the filler nano-silica is not contained, and other conditions are consistent with Example 1.

[0070] Comparative Example 6

[0071] Compared with Example 1, the difference of this comparative example is that the regenerated catalyst iron naphthenate is not contained, and other conditions are consistent with Example 1.

[0072] Comparative Example 7

[0073] Compared with Example 1, the difference of this comparative example is that the petroleum resin is 5.5%, the nano-silicon dioxide is 0.5%, and the iron naphthenate is 0.5%. Other conditions are the same as those of Example 1.

[0074] Commercially available XT-2

[0075] The commercially available asphalt regeneration agent XT-2 was purchased from Changzhou Zhuozhuo New Material Technology Co., Ltd.

[0076] Test example: Aged asphalt regeneration and restoration test

[0077] The specific test methods are as follows:

[0078] (1) Use an indoor automatic asphalt extraction instrument to extract aged asphalt from recycled pavement asphalt and test the three major indicators of aged asphalt, including penetration, softening point and ductility;

[0079] (2) Preparation and testing of recycled asphalt mixture:

[0080] 200g of recycled pavement asphalt (having an asphalt-to-stone ratio of 5%) was added to each of 200g of each of the asphalt rejuvenators prepared in Examples 1-3 and Comparative Examples 1-7 of the present invention, as well as 20g of a commercially available asphalt rejuvenator (XT-2 from Changzhou Zhuozhuo New Material Technology Co., Ltd.). The mixtures were then heated to 130°C and stirred for 5 minutes to produce regenerated asphalt mixtures. Four major performance indicators of the regenerated asphalt mixtures were then tested. The test results are shown in Table 1.

[0081] Table 1 Test results of recycled asphalt mixture indicators

[0082]

[0083]

[0084] Data Analysis and Conclusions:

[0085] As can be seen from Table 1, after adding the asphalt regeneration agent prepared in Examples 1 to 3 of the present invention, the performance of the aged asphalt is well restored. The viscosity of the asphalt mixture in Examples 1 to 3 is moderate (400 to 450 mPa·s), which shows that under the formulation and preparation process, the asphalt regeneration agent prepared can make the regenerated asphalt have suitable flow properties and facilitate construction operations. The needle penetration recovery rate is ≥85%, indicating that the regeneration agent in the example can effectively restore the needle penetration of aged asphalt, improve the rheological properties of asphalt, and make it closer to the performance of new asphalt. The softening point is ≥52°C, reflecting that the regenerated asphalt has good high-temperature stability, is not prone to excessive deformation in high-temperature environments, and can reduce the occurrence of diseases such as rutting. The ductility is ≥30cm, indicating that the regenerated asphalt has good flexibility and crack resistance, is not prone to cracking at low temperatures or when subjected to external force, and has excellent comprehensive performance.

[0086] Comparative Example 1, which lacks bio-oil (e.g., castor oil), shows a significant increase in viscosity compared to the examples, with penetration recovery dropping to 70%, and a significant decrease in softening point and ductility. This demonstrates that bio-oil (e.g., castor oil) plays an important role in reducing viscosity, improving penetration recovery, and ductility. It also has a certain effect on raising the softening point, helping to enhance the compatibility of the regeneration agent with asphalt, replenishing light oil components, and improving flexibility and compatibility.

[0087] Comparative Example 2, which lacks an SBS modifier, exhibits lower viscosity compared to the Example, with a penetration recovery rate of 75%, a softening point of 49.0°C, and a significant decrease in ductility to 12.4 cm. This demonstrates that SBS, as a polymer modifier, is crucial for improving the high-temperature rutting resistance and low-temperature cracking resistance of recycled asphalt, enhancing its cohesion and elasticity.

[0088] In Comparative Example 3, which lacks a surfactant, the viscosity increased, the penetration recovery rate was 68%, and the softening point and ductility were also lower than those in the Example. This suggests that surfactants (such as fatty acid amides) can effectively improve the dispersibility of the regeneration agent in aged asphalt, promote the fusion of new and old asphalt, and have a positive effect on improving penetration recovery rate and ductility.

[0089] Comparative Example 4, without a tackifier (petroleum resin), showed a decrease in viscosity, a penetration recovery rate of 72%, and a decrease in both softening point and ductility. This demonstrates the importance of petroleum resin as a tackifier in increasing asphalt viscosity, softening point, and ductility, thereby enhancing asphalt's bonding properties.

[0090] Comparative Example 5, which contains no filler (nanosilica), shows relatively little change in various indicators compared to the examples, but the viscosity is slightly lower than that of the examples, and the penetration recovery rate, softening point, and ductility are also slightly reduced. This suggests that while nanosilica, as a filler, may not have as significant an impact on overall performance as other ingredients, it still plays a role in improving the overall performance of asphalt, especially its mechanical properties.

[0091] Comparative Example 6, without the regeneration catalyst (iron naphthenate), showed reduced viscosity, a penetration recovery rate of 78%, and lower softening point and ductility than the examples. This indicates that iron naphthenate, as a regeneration catalyst, effectively accelerates the breakage and recombination of chemical bonds in aged asphalt, improving penetration recovery and ductility, and significantly enhancing the performance of regenerated asphalt.

[0092] In Comparative Example 7, the ratio of the functional additives was adjusted: the viscosity increased to , the penetration recovery rate was 82%, and the softening point and ductility also differed from those in the Example. This indicates that the ratio of functional additives affects the properties of recycled asphalt. A reasonable ratio can effectively enable the various components to work together and optimize the properties of recycled asphalt.

[0093] Comparison of commercially available products

[0094] XT-2 rejuvenator: Its viscosity was too high (620 mPa·s), its penetration recovery rate was only 65%, and its ductility was extremely low (10.5 cm), far inferior to the performance of the examples of the present invention. This demonstrates that the asphalt rejuvenator prepared by the present invention outperforms commercially available products in restoring the properties of aged asphalt and improving its rheological and road performance.

[0095] The embodiments described above are some, but not all, of the embodiments of the present invention. The detailed description of the embodiments of the present invention is not intended to limit the scope of the invention as claimed, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are also within the scope of protection of the present invention.

Claims

1. A high-utilization RAP asphalt regeneration agent, characterized in that: The following components are included by mass percentage: Petroleum-based softener 30% to 50%, Biomass oil 10% to 20%, Polymer modifier 5% to 15%, Surfactant 1% to 5%, Antioxidants 0.5% to 2%, Functional additives 2% to 10%.

2. The regeneration agent according to claim 1, characterized in that The petroleum-based softener is selected from at least one of aromatic oil, naphthenic oil, mineral oil or catalytic cracking slurry.

3. The regeneration agent according to claim 1, characterized in that The biomass oil is at least one of castor oil, tall oil or palm oil.

4. The regeneration agent according to claim 1, characterized in that The polymer modifier is at least one of SBS, SBR or waste tire rubber powder.

5. The regeneration agent according to claim 1, characterized in that The surfactant is at least one of a fatty acid amide, an organosilicon compound or a nonionic surfactant.

6. The regeneration agent according to claim 1, characterized in that The antioxidant is at least one of hindered phenolic and amine antioxidants.

7. The regeneration agent according to claim 1, characterized in that The functional additives include a tackifier, a filler and a regeneration catalyst; the tackifier is petroleum resin or prickly ash resin, the filler is carbon black or nano silicon dioxide, and the regeneration catalyst is an organic metal salt.

8. The regeneration agent according to claim 7, characterized in that The mass ratio of the tackifier, filler and regeneration catalyst is (2-4):(1-3):(1-2).

9. A method for preparing the regeneration agent according to any one of claims 1 to 8, characterized in that: The following steps are involved: (a) mixing a petroleum-based softener and biomass oil at 60-80° C. and stirring for 10-20 minutes; (b) adding a polymer modifier, a surfactant, and an antioxidant to the mixture of step (a) in sequence, raising the temperature to 100-120° C. and reacting for 30-60 minutes; (c) Cooling the mixture from step (b) to 50-70° C., adding the functional additive and continuing to stir until uniform.

10. The preparation method according to claim 9, characterized in that The stirring rate in step (a) is 500-800 rpm, and the heating rate in step (b) is 2-5° C. / min.

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