Normal-temperature type bio-based asphalt cold patch material and preparation method thereof

Abstract

This invention discloses a room-temperature bio-based asphalt cold patch and its preparation method. The cold patch comprises 96.5-98 wt% recycled asphalt pavement material and 2-3.5 wt% bio-based asphalt cold patch liquid. The cold patch liquid comprises 60-70 wt% base asphalt, 10-20 wt% bio-based diluent, and 20-30 wt% bio-based regenerator. The preparation method includes the following steps: preparing epoxidized soybean oil methyl ester and hydrogenated ricinoleate methyl ester; mixing vegetable oil and its derivatives, fatty acids and their esters, natural small-molecule organic components, and oxalic acid at room temperature to obtain a bio-based diluent; heating the base asphalt to a fluid state and adding the bio-based regenerator, followed by cooling and adding the bio-based diluent to obtain the cold patch liquid; and adding the cold patch liquid to the recycled asphalt pavement material and mixing to obtain the cold patch. The bio-based asphalt cold patch of this invention has high initial strength, high pavement stability after repair, and significantly reduces the rework rate and the probability of recurring defects.

Description

Technical Field

[0001] This invention belongs to the field of road repair material design and preparation technology, specifically relating to a room-temperature bio-based asphalt cold patch material and its preparation method. Background Technology

[0002] With the rapid development of transportation infrastructure and the continuous expansion of the road network, the demand for road maintenance and repair is increasing. Potholes are one of the major defects of asphalt pavements of all grades of highways. They usually refer to bowl-shaped voids of varying sizes and steep edges that are formed on the surface of the pavement due to the combined effects of various factors. Their size ranges from a few centimeters to tens of centimeters, or even larger. These defects not only affect the performance and driving comfort of asphalt pavements, but also shorten their service life.

[0003] In road maintenance and repair, the performance of road repair materials has a significant impact on road service life and driving safety. Existing road repair materials mainly include hot-mix asphalt (HMA) and cold-mix asphalt patch materials. HMA requires on-site heating during repair, which increases maintenance costs and labor intensity. It is also highly susceptible to weather and temperature variations, requiring high construction temperatures during the repair process. Furthermore, HMA generates significant amounts of smoke and harmful gases during repair, causing environmental pollution. Cold-mix asphalt patch materials offer far greater advantages in environmental adaptability, material storage, and transportation than HMA, and do not produce high-temperature harmful gases, making them the preferred material for road repair. However, due to their slow curing speed and insufficient early strength development, the repaired pavement is prone to premature damage, affecting the quality and service life of the road repair.

[0004] With increasing global emphasis on green and low-carbon development, the limitations of traditional road repair materials in terms of sustainability are becoming increasingly apparent. Currently, mainstream hot-mix asphalt mixtures suffer from high energy consumption (requiring heating to over 160°C) and large carbon emissions, while conventional cold-mix asphalt has significant shortcomings in terms of material performance (low early strength and poor durability) and environmental friendliness (containing volatile solvents).

[0005] Reclaimed asphalt pavement (RAP) is recycled and reused to replace natural stone in the preparation of asphalt cold patch material, which is an effective way to realize the resource utilization of solid waste. This technology can not only effectively solve the problems of waste material stockpiling and environmental pollution, but also release the residual value of old materials. At the same time, using renewable biomass materials to prepare asphalt cold patch fluid can reduce dependence on petroleum resources and reduce carbon emissions during the production process.

[0006] Therefore, there is an urgent need to develop a room-temperature bio-based cold patch asphalt and its preparation method, focusing on a low-carbon recycled asphalt cold patch design scheme that incorporates bio-based binder, room-temperature cold mixing and paving, and 100% RAP material replacement, to solve the problem of pothole repair on asphalt pavements. Summary of the Invention

[0007] To address the problems existing in the prior art, this invention provides a room-temperature bio-based cold patch asphalt material. The bio-based cold patch asphalt material comprises, by mass percentage, 96.5-98 wt% recycled asphalt pavement material and 2-3.5 wt% bio-based cold patch liquid. The bio-based cold patch liquid comprises, by mass percentage, 60-70 wt% base asphalt, 10-20 wt% bio-based diluent, and 20-30 wt% bio-based regenerator.

[0008] Preferably, the asphalt pavement recycled material includes nine particle size grades, and the mass percentage of each particle size grade in the asphalt pavement recycled material is as follows: 9.5-13.2mm particle size accounts for 6-10wt%, 4.75-9.5mm particle size accounts for 15-23wt%, 2.36-4.75mm particle size accounts for 25-33wt%, 1.18-2.36mm particle size accounts for 15-19wt%, 0.6-1.18mm particle size accounts for 5-9wt%, 0.3-0.6mm particle size accounts for 3-7wt%, 0.15-0.3mm particle size accounts for 3-7wt%, 0.075-0.15mm particle size accounts for 3-7wt%, and 0-0.075mm particle size accounts for 3-7wt%.

[0009] Alternatively, the asphalt pavement recycled material comprises ten particle size grades, with each particle size grade accounting for the following mass percentage of the asphalt pavement recycled material: 13.2-16mm 6-10wt%, 9.5-13.2mm 20-24wt%, 4.75-9.5mm 15-25wt%, 2.36-4.75mm 10-18wt%, 1.18-2.36mm 8-12wt%, 0.6-1.18mm 3-7wt%, 0.3-0.6mm 3-7wt%, 0.15-0.3mm 3-7wt%, 0.075-0.15mm 5-7wt%, and 0-0.075mm 3-7wt%.

[0010] Alternatively, the asphalt pavement recycled material includes twelve particle size grades, with each particle size grade accounting for the following mass percentage of the recycled asphalt pavement material: 19-26.5mm particle size accounts for 6-10wt%, 16-19mm particle size accounts for 5-9wt%, 13.2-16mm particle size accounts for 5-13wt%, 9.5-13.2mm particle size accounts for 8-12wt%, and 4.75-9.5mm particle size accounts for 15-19wt%. Particle size 2.36-4.75mm accounts for 12-18wt%, particle size 1.18-2.36mm accounts for 6-10wt%, particle size 0.6-1.18mm accounts for 5-7wt%, particle size 0.3-0.6mm accounts for 5-7wt%, particle size 0.15-0.3mm accounts for 5-7wt%, particle size 0.075-0.15mm accounts for 2-6wt%, and particle size 0-0.075mm accounts for 2-6wt%.

[0011] The main components of the recycled asphalt pavement material are old asphalt and old aggregate. The outer surface of the old aggregate is partially or completely covered with old asphalt, and the proportion of old asphalt is 25-35% overall.

[0012] In any of the above embodiments, it is preferred that the bio-based diluent comprises the following components by mass percentage: 40-60 wt% vegetable oil and its derivatives, 25-40 wt% fatty acids and their esters, 10-20 wt% natural small molecule organic compounds, and 5-8 wt% oxalic acid.

[0013] In any of the above embodiments, it is preferred that the mass percentage of each substance in the vegetable oil and its derivative components is 60-70 wt% vegetable oil, 15-20 wt% epoxidized soybean oil methyl ester, and 15-20 wt% hydrogenated castor oil methyl ester; the vegetable oil is any one or more of soybean oil, sunflower seed oil, corn oil, tung oil, and linseed oil.

[0014] In any of the above embodiments, it is preferred that the mass percentage of each substance in the fatty acid and its ester components is 30-40 wt% for fatty acids and 60-70 wt% for fatty acid esters; the fatty acid is any one or more of oleic acid, linoleic acid, and stearic acid; and the fatty acid ester is any one or more of methyl oleate, ethyl oleate, propyl oleate, methyl linoleate, ethyl linoleate, and glyceryl stearate.

[0015] In any of the above embodiments, it is preferred that the mass percentage of each substance in the natural small molecule organic component is 75-85 wt% phytosterol, 5-10 wt% sucrose fatty acid ester, and 10-15 wt% limonene; wherein the phytosterol is any one or more of β-sitosterol, brassosterol, and stigmasterol.

[0016] In any of the above embodiments, preferably, the bio-based regenerator comprises the following components by mass percentage: 47-55 wt% vegetable oil, 12-16 wt% terpene phenolic resin, 5-8 wt% antioxidant, 3-5 wt% surfactant, 6-8 wt% plasticizer, 6-8 wt% stabilizer, and 8-12 wt% bio-based modifier. The amount of bio-based modifier added increases with the amount of vegetable oil added. Within the mass percentage range of the bio-based modifier and the vegetable oil, for every 2 wt% increase in the amount of vegetable oil added, the amount of bio-based modifier added increases by 0.8-1.2 wt%.

[0017] In the bio-based regenerator of the present invention, the vegetable oil includes any one or more of rapeseed oil, tung oil, corn oil, and peanut oil. The antioxidant comprises, by mass percentage, 28-32 wt% dilaurate thiodipropionate, 58-65 wt% furfural, and 5-10 wt% vitamin E. The surfactant is docosyldimethylammonium bromide. The plasticizer is epoxidized soybean oil. The stabilizer comprises, by mass percentage, 38-45 wt% bentonite, 38-45 wt% diatomaceous earth, and 15-22 wt% talc.

[0018] The bio-based modifier comprises, by mass percentage, algal extract 18-25 wt%, sulfonated lignin 45-55 wt%, and chitin 27-32 wt%; and the algal extract comprises, by mass percentage, spirulina extract 42-48 wt%, chlorella extract 42-48 wt%, and brown algae extract 8-15 wt%.

[0019] The preparation method of the bio-based regenerant includes the following steps in sequence:

[0020] Step (1): Mix bentonite, diatomaceous earth and talc powder evenly at room temperature according to the designed material ratio to obtain a stabilizer; Step (2): Mix spirulina extract, chlorella extract and brown algae extract evenly at room temperature according to the designed material ratio to obtain an algae extract.

[0021] Step (3): Weigh each raw material according to the designed material ratio and set aside;

[0022] Step (4): Put the vegetable oil into the reaction vessel and heat it at a rate of 2-5℃ / min to 50-70℃, and keep the temperature constant. Stir slowly during the heating process to ensure that the vegetable oil is heated evenly.

[0023] Step (5): Keep the temperature in the reactor at 50-70℃, add the surfactant to the reactor and stir until the surfactant is completely dissolved. After dissolution, continue stirring for 5-8 minutes at a stirring speed of 200-400 r / min.

[0024] Step (6): Keep the temperature in the reactor at 50-70℃, add the terpene phenolic resin to the reactor and stir until the terpene phenolic resin is completely dissolved. After dissolution, continue stirring for 5-8 minutes at a stirring speed of 200-400 r / min.

[0025] Step (7): Keep the temperature in the reactor at 50-70℃. First, add dilauryl thiodipropionate and vitamin E from the antioxidant to the reactor and stir for 3-5 minutes. Then, add furfural from the antioxidant to the reactor and stir for 90-120 seconds. The stirring speed is 200-400 r / min.

[0026] Step (8): Increase the temperature in the reactor from 50-70℃ to 80-90℃ at a heating rate of 2-5℃ / min. First, add the components chitin and sulfonated lignin in the bio-based modifier to the reactor and stir for 2-3 minutes. Then, add the algae extract in the bio-based modifier to the reactor and stir for 10-15 minutes at a stirring speed of 200-400 r / min.

[0027] Step (9): Keep the temperature in the reactor at 80-90℃, add plasticizer and stabilizer to the reactor and stir for 30-40 minutes at a stirring speed of 200-400 r / min. After stirring is completed, the bio-based asphalt regenerator is obtained.

[0028] This invention also provides a method for preparing a room-temperature bio-based cold patch asphalt, used to prepare the room-temperature bio-based cold patch asphalt described in any of the above claims. The preparation method includes the following steps in sequence:

[0029] Step 1: Prepare epoxidized soybean oil methyl ester and hydrogenated castor oil methyl ester according to the designed process parameters;

[0030] Step 2: Weigh out each raw material according to the designed material ratio and set aside;

[0031] Step 3: Mix vegetable oil, epoxidized soybean oil methyl ester, and hydrogenated ricinoleate methyl ester at room temperature according to the designed material ratio to obtain vegetable oil and its derivative components; mix fatty acids and fatty acid esters at room temperature according to the designed material ratio to obtain fatty acids and their ester components; mix phytosterols, sucrose fatty acid esters, and limonene at room temperature according to the designed material ratio to obtain natural small molecule organic components; mix vegetable oil and its derivative components, fatty acids and their ester components, natural small molecule organic components, and oxalic acid at room temperature according to the designed material ratio to obtain a bio-based diluent.

[0032] Step 4: Place the base asphalt into a container, then place the container containing the base asphalt into an oven and heat it until the base asphalt becomes fluid. After heating, remove the container containing the fluid base asphalt from the oven, and add the bio-based regenerator while stirring. After adding the bio-based regenerator, continue stirring to ensure that it is completely dissolved.

[0033] Step 5: After the bio-based regenerator is completely dissolved, stir and cool down. After cooling to a certain temperature, add the bio-based diluent while stirring. After the addition is completed, continue stirring to make the bio-based diluent completely dissolved, thus obtaining the bio-based asphalt cold patching solution.

[0034] Step Six: According to the designed material ratio, put the recycled asphalt pavement materials of each particle size into the mixing pot and mix them. After the mixing is completed, add the bio-based asphalt cold patch liquid into the mixing pot and continue mixing to obtain the bio-based asphalt cold patch material.

[0035] Preferably, in step one, the preparation method of the epoxidized soybean oil methyl ester is as follows: epoxidized soybean oil and acetone are added to a 100mL flask, the amount of epoxidized soybean oil added is 10-15g, and the amount of acetone added is 15-20% of the amount of epoxidized soybean oil added; 50-60mL of methanol solution with an alkali concentration of 0.05mol / L is added to the flask; the mixture of epoxidized soybean oil, acetone, and methanol is electromagnetically stirred at room temperature for 1-1.5h; after the reaction is completed, the reaction product is washed with deionized water to remove the remaining alkali catalyst, and then the remaining water is removed with anhydrous sodium sulfate; the reaction product is dried in a vacuum oven at 50-60℃ for 1-2h to obtain epoxidized soybean oil methyl ester.

[0036] In any of the above embodiments, preferably, in step one, the preparation method of the hydrogenated methyl ricinoleate is as follows: methyl ricinoleate and a copper-nickel bimetallic catalyst are added to a reaction vessel, the amount of methyl ricinoleate added is 1-2g, and the amount of the copper-nickel bimetallic catalyst added is 0.8-1.2% of the amount of methyl ricinoleate added; the reaction vessel is continuously purged with nitrogen gas at a flow rate of 5-20L / min for 5-8min to replace the air in the reaction vessel; hydrogen gas at 2-2.5MPa is introduced into the reaction vessel, and the temperature is raised to 125-135℃, and the substances in the reaction vessel react at this temperature for 10-12h; after the reaction is completed, the reaction product is washed with ethyl acetate to remove the catalyst, thereby obtaining hydrogenated methyl ricinoleate.

[0037] In any of the above schemes, it is preferred that in step four, the base asphalt is heated to a temperature of 155-175℃ in the oven for 1-2 hours, and the mixture is stirred for 5-8 minutes after the addition of the bio-based regenerator.

[0038] In any of the above schemes, it is preferred that in step five, after cooling to 45-55℃, a bio-based diluent is added, and stirring is continued for 10-15 minutes after adding the bio-based diluent.

[0039] In any of the above schemes, it is preferred that, in step six, the recycled asphalt pavement materials of various particle sizes are placed into a mixing pot for mixing, with a mixing temperature of 25±5℃, a mixing time of 90-150s, and a mixing speed of 100-200r / min; bio-based asphalt cold patching liquid is added to the mixing pot for further mixing, with a mixing temperature of 25±5℃, a mixing time of 90-150s, and a mixing speed of 100-200r / min.

[0040] The particle size ranges involved in this invention include: 19-26.5 mm, 16-19 mm, 13.2-16 mm, 9.5-13.2 mm, 4.75-9.5 mm, 2.36-4.75 mm, 1.18-2.36 mm, 0.6-1.18 mm, 0.3-0.6 mm, 0.15-0.3 mm, 0.075-0.15 mm, and 0-0.075 mm, i.e., 19 mm ≤ particle size < 26 mm. The particle sizes are 5mm, 16mm ≤ particle size < 19mm, 13.2mm ≤ particle size < 16mm, 9.5mm ≤ particle size < 13.2mm, 4.75mm ≤ particle size < 9.5mm, 2.36mm ≤ particle size < 4.75mm, 1.18mm ≤ particle size < 2.36mm, 0.6mm ≤ particle size < 1.18mm, 0.3mm ≤ particle size < 0.6mm, 0.15mm ≤ particle size < 0.3mm, 0.075mm ≤ particle size < 0.15mm, and 0mm < particle size < 0.075mm. For each particle size range, the particle size obtained after passing the material through the upper and lower sieve openings sequentially is between the upper and lower sieve openings. For example, a particle size of 1.18-2.36mm means the material is passed through a 2.36mm sieve and a 1.18mm sieve sequentially, resulting in a particle size between 1.18 and 2.36mm.

[0041] This invention utilizes multiple biomass components, each with the following functions: Vegetable oils and their derivatives possess excellent permeability and plasticizing ability, balancing the components and restoring the properties of aged asphalt. Fatty acids and their esters can undergo lubrication and polarity neutralization reactions with aged asphalt, alleviating the hardening effect caused by the entanglement of gums and asphaltenes in the aged asphalt. Natural small-molecule organic components possess good polarity and complexing ability, used to regulate interfacial activity and improve dispersibility and stability. Sageinic acid has certain antioxidant functions, inhibiting further oxidative aging of asphalt and improving long-term durability. A bio-based regenerator can restore and replenish missing components in aged asphalt, rebalancing the original chemical composition and structure of the aged asphalt and effectively restoring its properties.

[0042] This invention innovatively proposes a low-carbon recycled asphalt pavement pothole repair solution based on bio-based binder technology. Its core breakthroughs are reflected in the following three aspects: First, it focuses on the empowerment of bio-based binders, using renewable biomass raw materials to partially replace petroleum-based asphalt / base asphalt, reducing dependence on fossil resources and simultaneously reducing carbon emissions during production. Second, it employs a room-temperature cold-mix and cold-lay process, breaking through the limitations of traditional hot-mix processes to achieve room-temperature mixing and construction, significantly reducing energy consumption. Third, it uses 100% RAP material to replace aggregate and mineral powder, achieving efficient recycling of asphalt pavement recycled material (RAP) through activation and gradation optimization technologies, avoiding resource waste. The technical system of this invention not only improves the mechanical properties (including initial strength and long-term strength) and durability of cold-mix asphalt, but also aligns with the dual-carbon strategy goals throughout the entire lifecycle of production, transportation, construction, and operation, promoting the transformation of the road maintenance industry towards a circular economy and sustainable development.

[0043] The room-temperature bio-based cold patching material and its preparation method of the present invention have the following beneficial effects:

[0044] (1) The bio-based asphalt cold patch liquid of the present invention uses bio-based raw materials, which are green and environmentally friendly, do not contain petroleum solvents, and do not pollute the environment during the entire production, transportation, construction and operation cycle. It also does not pose any health hazards to construction personnel and users, which is in line with the dual-carbon strategy development direction.

[0045] (2) The bio-based asphalt cold patch liquid of the present invention has a flash point greater than 130°C, which is significantly better than traditional petroleum-based solvent products. It can effectively reduce the safety hazards of fire or explosion during transportation, storage or on-site operation, and ensure the safety of construction process and environment.

[0046] (3) The bio-based asphalt cold patch material of the present invention does not rely on solvent evaporation for curing, and abandons the dependence of traditional asphalt cold patch material on open gradation. The present invention can adopt continuous gradation design to form a denser structural layer, further improving the strength (including initial strength and long-term strength) and durability of the repair area.

[0047] (4) The bio-based asphalt cold patch liquid of the present invention has good fluidity at room temperature (25±5℃) and can be directly mixed with asphalt pavement recycled material (RAP) at room temperature without heating, which significantly reduces energy consumption and equipment investment.

[0048] (5) The bio-based asphalt cold patch material of the present invention has strong adaptability and can be constructed in all weather conditions. It can maintain good mixing and bonding performance in low temperature, rain, snow and high humidity environments, and can also be compacted and cured in sub-zero environments. It can be used immediately after repair. After repair, it can quickly bear vehicle loads after simple compaction and be opened to traffic immediately, significantly reducing traffic pressure caused by road maintenance.

[0049] (6) The bio-based asphalt cold patch material of the present invention has strong manual / mechanical compatibility. It is suitable for manual repair of small defects and can be used in conjunction with pavers, rollers and other equipment to carry out large defects or large-area paving operations.

[0050] (7) The bio-based asphalt cold patching material of the present invention has good workability, high initial strength and long-term strength, excellent durability and long storage period, and can be used all year round and in all weather conditions. It is also widely applicable to different application scenarios such as national and provincial trunk roads, expressways, urban roads and highway service areas. The repaired pavement has high stability, which greatly reduces the probability of rework and the probability of recurrence of defects, effectively improving the service life of roads and traffic efficiency. Attached Figure Description

[0051] Figure 1 This is a process flow diagram of a preferred embodiment of the ambient temperature bio-based cold patching material and its preparation method according to the present invention;

[0052] Figure 2 for Figure 1 A photograph of the bio-based asphalt cold patching solution prepared in the illustrated embodiment;

[0053] Figure 3 for Figure 1 The illustrated embodiment shows a photograph of the process of adding bio-based asphalt cold patching fluid to asphalt pavement recycled materials;

[0054] Figure 4 for Figure 1 Photographs of the bio-based cold patch asphalt prepared in the embodiments shown, wherein: (a) bio-based cold patch asphalt, (b) specimen of bio-based cold patch asphalt;

[0055] Figure 5 for Figure 1 The illustrated embodiment shows a photograph of bio-based asphalt cold patch material being filled into a pothole;

[0056] Figure 6 for Figure 1 The illustrated embodiment shows a photograph of the compacted bio-based asphalt cold patch material in a pothole;

[0057] Figure 7 for Figure 1 The illustrated embodiments are photographs taken after the potholes have been repaired and the equipment has been in normal operation for a certain period of time, wherein: (a) 7 days, (b) 6 months, (c) 12 months, (d) 18 months, (e) 24 months. Detailed Implementation

[0058] To further understand the invention, the following detailed description of the invention will be provided in conjunction with specific embodiments.

[0059] Example 1:

[0060] like Figure 1 As shown, in a preferred embodiment of the ambient temperature bio-based cold patch material of the present invention, the mass percentage of each substance in the bio-based cold patch material is 97.25 wt% asphalt pavement recycled material and 2.75 wt% bio-based cold patch liquid. The mass percentage of each substance in the bio-based cold patch liquid is 65 wt% 70# base asphalt, 15 wt% bio-based diluent, and 20 wt% bio-based regenerator.

[0061] The asphalt pavement recycled material comprises nine particle size grades, with each grade accounting for the following percentage by mass: 9.5-13.2 mm 6-10 wt%, 4.75-9.5 mm 15-23 wt%, 2.36-4.75 mm 25-33 wt%, 1.18-2.36 mm 15-19 wt%, 0.6-1.18 mm 5-9 wt%, 0.3-0.6 mm 3-7 wt%, 0.15-0.3 mm 3-7 wt%, 0.075-0.15 mm 3-7 wt%, and 0-0.075 mm 3-7 wt%. The content ranges for each particle size grade are applicable to this embodiment, and the total content of all particle size grades is 100%.

[0062] Specifically, in this embodiment, the particle size distribution is as follows: 9.5-13.2mm accounts for 8wt%, 4.75-9.5mm accounts for 19wt%, 2.36-4.75mm accounts for 29wt%, 1.18-2.36mm accounts for 17wt%, 0.6-1.18mm accounts for 7wt%, 0.3-0.6mm accounts for 5wt%, 0.15-0.3mm accounts for 5wt%, 0.075-0.15mm accounts for 5wt%, and 0-0.075mm accounts for 5wt%. The main components of the recycled asphalt pavement material are old asphalt and old aggregate. The outer surface of the old aggregate is partially or completely covered with old asphalt, and the overall proportion of old asphalt is 30%.

[0063] The bio-based diluent comprises the following components by mass percentage: 47 wt% vegetable oil and its derivatives, 32 wt% fatty acids and their esters, 15 wt% natural small molecule organic compounds, and 6 wt% oxalic acid.

[0064] The composition of the vegetable oil and its derivatives comprises, by mass percentage, 65 wt% vegetable oil, 18 wt% epoxidized soybean oil methyl ester, and 17 wt% hydrogenated castor oil methyl ester. The vegetable oil is any one of soybean oil, sunflower oil, corn oil, tung oil, and linseed oil.

[0065] The fatty acid and its ester components comprise, by mass percentage, 35 wt% fatty acid and 65 wt% fatty acid esters. The fatty acid is any one of oleic acid, linoleic acid, and stearic acid, and the fatty acid ester is any one of methyl oleate, ethyl oleate, propyl oleate, methyl linoleate, ethyl linoleate, and glyceryl stearate.

[0066] The mass percentage of each substance in the natural small molecule organic component is 80 wt% phytosterol, 8 wt% sucrose fatty acid ester, and 12 wt% limonene; the phytosterol is any one of β-sitosterol, brassosterol, and stigmasterol.

[0067] The bio-based regenerator comprises the following components by mass percentage: 47 wt% vegetable oil, 16 wt% terpene phenolic resin, 8 wt% antioxidant, 5 wt% surfactant, 8 wt% plasticizer, 8 wt% stabilizer, and 8 wt% bio-based modifier. The amount of bio-based modifier increases with the amount of vegetable oil added. Within the range of the mass percentages of bio-based modifier and vegetable oil, for every 2 wt% increase in the amount of vegetable oil, the amount of bio-based modifier increases by 0.8-1.2 wt%. In this embodiment, both vegetable oil and bio-based modifier are added at the minimum required amounts.

[0068] In this embodiment of the bio-based regenerator, the vegetable oil includes any one of rapeseed oil, tung oil, corn oil, and peanut oil. The antioxidant comprises, by mass percentage, 30 wt% dilaurate thiodipropionate, 62 wt% furfural, and 8 wt% vitamin E. The surfactant is docosyldimethylammonium bromide. The plasticizer is epoxidized soybean oil. The stabilizer comprises, by mass percentage, 41 wt% bentonite, 41 wt% diatomaceous earth, and 18 wt% talc.

[0069] The bio-based modifier comprises, by mass percentage, 21 wt% algal extract, 50 wt% sulfonated lignin, and 29 wt% chitin; and by mass percentage, 45 wt% spirulina extract, 45 wt% chlorella extract, and 10 wt% brown algae extract.

[0070] It should be noted that the three algal extracts are substances obtained through further extraction from purchased algal extracts. There are no specific restrictions on the type or manufacturer of the original purchased algal extracts. The further extraction method is as follows (main parameters): Bioactive substances in algae are extracted using liquid-phase extraction with ethanol as the solvent. Algal powder and ethanol are added at a ratio of 1:15-20 (w / v) (w represents mass, g; v represents volume, ml), and extraction is carried out at 55-65℃ for 2-3 hours. For brown algae and Chlorella, the pH is adjusted to 4.0-5.0 with 0.1 mol / L HCl, and for Spirulina, the pH is adjusted to 7.5-8.5 with 0.1 mol / L NaOH. After filtration, the extract is obtained by rotary evaporation. The above parameter ranges apply to this embodiment.

[0071] The preparation method of the bio-based regenerant includes the following steps in sequence:

[0072] Step (1): Mix bentonite, diatomaceous earth and talc powder evenly at room temperature according to the designed material ratio to obtain a stabilizer; Step (2): Mix spirulina extract, chlorella extract and brown algae extract evenly at room temperature according to the designed material ratio to obtain an algae extract.

[0073] Step (3): Weigh each raw material according to the designed material ratio and set aside;

[0074] Step (4): Heat the vegetable oil in the reaction vessel at a rate of 2.5℃ / min to 60℃ and keep the temperature constant. Stir slowly during the heating process to ensure that the vegetable oil is heated evenly.

[0075] Step (5): Keep the temperature in the reactor at 60°C, add the surfactant to the reactor and stir until the surfactant is completely dissolved. After dissolution, continue stirring for 6.5 min at a stirring speed of 300 r / min.

[0076] Step (6): Keep the temperature in the reactor at 60°C, add the terpene phenolic resin to the reactor and stir until the terpene phenolic resin is completely dissolved. After dissolution, continue stirring for 6.5 minutes at a stirring speed of 300 r / min.

[0077] Step (7): Keep the temperature in the reactor at 60°C. First, add dilauryl thiodipropionate and vitamin E from the antioxidant to the reactor and stir for 4 minutes. Then, add furfural from the antioxidant to the reactor and stir for 105 seconds. The stirring speed is 300 r / min.

[0078] Step (8): Increase the temperature in the reactor from 60°C to 85°C at a heating rate of 2.5°C / min. First, add the components chitin and sulfonated lignin from the bio-based modifier to the reactor and stir for 2.5 min. Then, add the algae extract from the bio-based modifier to the reactor and stir for 12.5 min at a stirring speed of 300 r / min.

[0079] Step (9): Keep the temperature in the reactor at 85°C, add plasticizer and stabilizer to the reactor and stir for 35 minutes at a stirring speed of 300 r / min. After stirring is completed, the bio-based asphalt regenerator is obtained.

[0080] This embodiment also provides a method for preparing a room-temperature bio-based cold patch asphalt, which is used to prepare the above-mentioned room-temperature bio-based cold patch asphalt. The preparation method includes the following steps in sequence:

[0081] Step 1: Prepare epoxidized soybean oil methyl ester and hydrogenated castor oil methyl ester according to the designed process parameters;

[0082] Step 2: Weigh out each raw material according to the designed material ratio and set aside;

[0083] Step 3: Mix vegetable oil, epoxidized soybean oil methyl ester, and hydrogenated ricinoleate methyl ester at room temperature according to the designed material ratio to obtain vegetable oil and its derivative components; mix fatty acids and fatty acid esters at room temperature according to the designed material ratio to obtain fatty acids and their ester components; mix phytosterols, sucrose fatty acid esters, and limonene at room temperature according to the designed material ratio to obtain natural small molecule organic components; mix vegetable oil and its derivative components, fatty acids and their ester components, natural small molecule organic components, and oxalic acid at room temperature according to the designed material ratio to obtain a bio-based diluent.

[0084] Step 4: Place the base asphalt into a container, then place the container containing the base asphalt into an oven and heat it until the base asphalt becomes fluid. After heating, remove the container containing the fluid base asphalt from the oven, and add the bio-based regenerator while stirring. After adding the bio-based regenerator, continue stirring to ensure that it is completely dissolved.

[0085] Step 5: After the bio-based regenerator is completely dissolved, stir and cool down. After cooling to a certain temperature, add the bio-based diluent while stirring. After the addition is completed, continue stirring to make the bio-based diluent completely dissolved, thus obtaining the bio-based asphalt cold patching solution.

[0086] Step Six: According to the designed material ratio, put the recycled asphalt pavement materials of each particle size into the mixing pot and mix them. After the mixing is completed, add the bio-based asphalt cold patch liquid into the mixing pot and continue mixing to obtain the bio-based asphalt cold patch material.

[0087] In step one, the preparation method of the epoxidized soybean oil methyl ester is as follows: epoxidized soybean oil and acetone are added to a 100mL flask, with the amount of epoxidized soybean oil added being 12.5g and the amount of acetone added being 17.5% of the amount of epoxidized soybean oil added; 55mL of a methanol solution with an alkali concentration of 0.05mol / L is added to the flask; the mixture of epoxidized soybean oil, acetone, and methanol is electromagnetically stirred at room temperature for 1.25h; after the reaction is completed, the reaction product is washed with deionized water to remove the remaining alkali catalyst, and then the remaining water is removed with anhydrous sodium sulfate; the reaction product is placed in a vacuum oven at 55℃ and dried for 1.5h to obtain epoxidized soybean oil methyl ester with a yield of 99.3%.

[0088] In step one, the preparation method of hydrogenated methyl ricinoleate is as follows: methyl ricinoleate and a copper-nickel bimetallic catalyst are added to a reaction vessel. The amount of methyl ricinoleate added is 1.5 g, and the amount of the copper-nickel bimetallic catalyst added is 1.0% of the amount of methyl ricinoleate added. The reaction vessel is continuously purged with nitrogen gas at a flow rate of 12 L / min for 6.5 min to replace the air in the reaction vessel. Hydrogen gas at 2.25 MPa is introduced into the reaction vessel, and the temperature is raised to 130°C. The substances in the reaction vessel react at this temperature for 11 h. After the reaction is completed, the reaction product is washed with ethyl acetate to remove the catalyst, thereby obtaining hydrogenated methyl ricinoleate with a yield of 93.4%. The copper-nickel bimetallic catalyst used in this embodiment can be prepared according to existing technology, as long as the molar ratio of copper to nickel is maintained at 1:5-8.

[0089] In step four, the base asphalt is heated to 165℃ in the oven for 1.5 hours, and then stirred for another 6.5 minutes after adding the bio-based regenerator.

[0090] In step five, after cooling to 50°C, add the bio-based diluent and continue stirring for 12.5 minutes.

[0091] In step six, recycled asphalt pavement materials of various particle sizes are placed into a mixing pot for mixing at a temperature of 25±5℃, a mixing time of 120s, and a mixing speed of 150r / min. Bio-based asphalt cold patching liquid is then added to the mixing pot for further mixing at a temperature of 25±5℃, a mixing time of 120s, and a mixing speed of 150r / min.

[0092] The construction process for repairing potholes using the bio-based asphalt cold patch material in this embodiment is as follows:

[0093] (1) Construction preparation: Occupy the road for construction in accordance with the relevant requirements of the operation control area in the Highway Maintenance Safety Operation Procedures, place isolation barriers and safety signs, check the machinery and equipment to ensure that they can operate normally, and confirm that the construction tools are complete.

[0094] (2) Pothole excavation: Following the principle of "square repair for round holes, straight repair for slanted holes", draw a square outline of appropriate size around the pothole. The outline should be parallel or perpendicular to the direction of traffic and extend 10-15cm beyond the damaged boundary of the pothole. The formed pothole wall should be kept as perpendicular to the road surface as possible, and the bottom of the pothole should be firm and flat. Finally, the old material that was excavated should be dug out of the pothole.

[0095] (3) Pothole cleaning: Clean the loose particles, dust and other residues from the four walls and bottom of the pothole. There should be no mud, rain, snow, ice or other debris in the pothole. The waste should be removed until a solid surface is visible. Apply tack coat evenly inside the pothole to ensure that the repair material is firmly bonded to the original road surface.

[0096] (4) Pothole filling: Pour bio-based asphalt cold patch material into the pothole until the filler is 1-2 cm higher than the pothole. When estimating the amount of patch material to be added, it can be increased by 10-20%. After filling, the center of the pothole should be slightly higher than the road surface and convex.

[0097] (5) Pothole compaction: After evenly spreading the material, select appropriate compaction tools and methods according to the size and depth of the repair area. The compaction degree should reach more than 90%. If the pothole depth is greater than 6cm, it should be filled in layers of 3-6cm, and compacted layer by layer. After the repair is completed, a layer of stone powder or fine sand can be evenly sprinkled on the surface and swept back and forth with a sweeping tool to fill the surface gaps with fine material and prevent the wheels from sticking.

[0098] (6) Sealing: Hot melt asphalt sealant or joint tape can be used to seal the joints of the potholes after repair to reduce the damage to the road surface and prevent rainwater from seeping through the joints, thereby extending the service life of the road surface.

[0099] (7) Open to traffic: The repaired pothole surface is smooth, flat, and free of wheel tracks. The pothole is well compacted around its edges and corners, with no loose material. Once the site is cleaned and passes inspection, traffic can be opened immediately without the need for maintenance or restrictions on vehicle load.

[0100] In this embodiment, the prepared bio-based asphalt cold patching solution is as follows: Figure 2 As shown; the process of adding bio-based asphalt cold patching fluid to asphalt pavement recycling materials is as follows: Figure 3 As shown; the prepared bio-based asphalt cold patching material is as follows Figure 4 As shown, (a) is a bio-based cold patch asphalt, and (b) is a specimen of the bio-based cold patch asphalt; the state of the bio-based cold patch asphalt filled into the pit is as follows. Figure 5 As shown; the state of the bio-based asphalt cold patch material in the pit after compaction is as follows. Figure 6 As shown. The condition after the potholes have been repaired and the system has been in normal operation for a certain period of time is as follows. Figure 7 As shown, (a) 7 days, (b) 6 months, (c) 12 months, (d) 18 months, (e) 24 months, from Figure 7 It can be seen that the repaired road surface has high stability and remains in good condition after 24 months of operation, greatly reducing the repair rate of defects and the probability of defects recurring or repeating.

[0101] The ambient temperature bio-based cold patch asphalt and its preparation method described in this embodiment have the following beneficial effects: It contains no petroleum solvents, causing no environmental pollution throughout the entire production, transportation, construction, and operation cycle; its flash point is greater than 130℃, effectively reducing the safety hazards of fire or explosion during transportation, storage, or on-site operations; it does not rely on solvent evaporation for curing, allowing for continuous gradation design to form a denser structural layer, further enhancing the initial and long-term strength of the repaired area; it has good fluidity at room temperature, allowing for direct mixing with recycled asphalt pavement materials at room temperature; it is highly adaptable, allowing for all-weather construction, and after repair, simple compaction is sufficient to quickly bear vehicle loads, enabling immediate traffic reopening; the repaired pavement exhibits high stability, greatly reducing the probability of rework and the recurrence of defects.

[0102] Example 2:

[0103] According to another preferred embodiment of the present invention, the material selection and proportioning, preparation process, technical principle, and beneficial effects are basically the same as those in Embodiment 1, except that:

[0104] The bio-based asphalt cold patch material comprises, by mass percentage, 98 wt% recycled asphalt pavement material and 2 wt% bio-based asphalt cold patch liquid. The bio-based asphalt cold patch liquid comprises, by mass percentage, 60 wt% 70# base asphalt, 10 wt% bio-based diluent, and 30 wt% bio-based regenerator.

[0105] The asphalt pavement recycled material comprises ten particle size grades, with each grade accounting for the following percentage by mass: 13.2-16 mm 6-10 wt%, 9.5-13.2 mm 20-24 wt%, 4.75-9.5 mm 15-25 wt%, 2.36-4.75 mm 10-18 wt%, 1.18-2.36 mm 8-12 wt%, 0.6-1.18 mm 3-7 wt%, 0.3-0.6 mm 3-7 wt%, 0.15-0.3 mm 3-7 wt%, 0.075-0.15 mm 5-7 wt%, and 0-0.075 mm 3-7 wt%. The content ranges for each particle size grade are applicable to this embodiment, and the total content of all particle size grades is 100%.

[0106] Specifically, in this embodiment, the particle size distribution is as follows: 13.2-16mm accounts for 8wt%, 9.5-13.2mm accounts for 22wt%, 4.75-9.5mm accounts for 20wt%, 2.36-4.75mm accounts for 14wt%, 1.18-2.36mm accounts for 10wt%, 0.6-1.18mm accounts for 5wt%, 0.3-0.6mm accounts for 5wt%, 0.15-0.3mm accounts for 5wt%, 0.075-0.15mm accounts for 6wt%, and 0-0.075mm accounts for 5wt%. The recycled asphalt pavement material comprises 25% old asphalt overall.

[0107] The bio-based diluent comprises the following components by mass percentage: 40 wt% vegetable oil and its derivatives, 40 wt% fatty acids and their esters, 12 wt% natural small-molecule organic compounds, and 8 wt% oxalic acid. The vegetable oil and its derivatives comprise the following components by mass percentage: 60 wt% vegetable oil, 20 wt% epoxidized soybean oil methyl ester, and 20 wt% hydrogenated castor oil methyl ester. The fatty acids and their esters comprise the following components by mass percentage: 30 wt% fatty acids and 70 wt% fatty acid esters. The natural small-molecule organic compounds comprise the following components by mass percentage: 75 wt% phytosterols, 10 wt% sucrose fatty acid esters, and 15 wt% limonene.

[0108] The bio-based regenerator comprises the following components by mass percentage: 51 wt% vegetable oil, 14 wt% terpene phenolic resin, 7.2 wt% antioxidant, 4 wt% surfactant, 7 wt% plasticizer, 7 wt% stabilizer, and 9.8 wt% bio-based modifier. The amount of bio-based modifier increases with the amount of vegetable oil added. Within the mass percentage range of the bio-based modifier and vegetable oil, for every 2 wt% increase in the amount of vegetable oil, the amount of bio-based modifier increases first by 0.8 wt%, then by 1.0 wt%, with each increase controlled within the range of 0.8-1.2 wt%.

[0109] The antioxidant comprises, by weight percentage, 28 wt% dilauryl thiodipropionate, 65 wt% furfural, and 7 wt% vitamin E. The stabilizer comprises, by weight percentage, 38 wt% bentonite, 45 wt% diatomaceous earth, and 17 wt% talc. The bio-based modifier comprises, by weight percentage, 18 wt% algal extract, 55 wt% sulfonated lignin, and 27 wt% chitosan; the algal extract comprises, by weight percentage, 42 wt% spirulina extract, 43 wt% chlorella extract, and 15 wt% brown algae extract.

[0110] The main parameters of the preparation process of the bio-based regenerant include: Step (4), heating the vegetable oil in the reactor at a heating rate of 2℃ / min to 50℃, stirring slowly during the heating process; Step (5), maintaining the temperature in the reactor at 50℃, adding the surfactant and stirring, continuing to stir for 5min after dissolution, with a stirring speed of 400r / min; Step (6), maintaining the temperature in the reactor at 50℃, adding the terpene phenolic resin and stirring, continuing to stir for 5min after dissolution, with a stirring speed of 400r / min; Step (7), maintaining the temperature in the reactor at 50℃, first Add dilaurate thiodipropionate and vitamin E and stir for 3 min, then add furfural and stir for 90 s at a stirring speed of 400 r / min; in step (8), raise the temperature in the reactor from 50°C to 80°C at a heating rate of 2°C / min, first add chitin and sulfonated lignin and stir for 2 min, then add algae extract and stir for 10 min at a stirring speed of 400 r / min; in step (9), keep the temperature in the reactor at 80°C, add plasticizer and stabilizer and stir for 30 min at a stirring speed of 400 r / min, and the bio-based asphalt regenerator is obtained.

[0111] In step one, the preparation method of the epoxidized soybean oil methyl ester is as follows: epoxidized soybean oil and acetone are added to a flask, with 10g of epoxidized soybean oil and 15% of the mass of epoxidized soybean oil in acetone; 50mL of methanol solution is added to the flask; the mixture is stirred electromagnetically for 1h; after the reaction is completed, the remaining alkaline catalyst and water are removed, and the reaction product is placed in a vacuum oven at 50℃ and dried for 2h to obtain epoxidized soybean oil methyl ester.

[0112] In step one, the preparation method of the hydrogenated methyl ricinoleate is as follows: methyl ricinoleate and a copper-nickel bimetallic catalyst are added to the reaction vessel, with 1g of methyl ricinoleate and the copper-nickel bimetallic catalyst accounting for 0.8% of the mass of methyl ricinoleate; the reaction vessel is continuously purged with nitrogen gas at a flow rate of 5L / min for 8min to remove air; hydrogen gas at 2MPa is introduced into the reaction vessel, and the temperature is raised to 125℃, and the substances react at this temperature for 12h; after the reaction is completed, the catalyst is removed to obtain hydrogenated methyl ricinoleate.

[0113] In step four, the base asphalt is heated to 155°C in the oven for 2 hours, and then stirred for another 5 minutes after adding the bio-based regenerator.

[0114] In step five, after cooling to 45°C, add the bio-based diluent and continue stirring for 10 minutes.

[0115] In step six, recycled asphalt pavement materials of various particle sizes are placed into a mixing pot for mixing at a temperature of 25±5℃, a mixing time of 90s, and a mixing speed of 200r / min. Bio-based asphalt cold patching liquid is then added to the mixing pot for further mixing at a temperature of 25±5℃, a mixing time of 90s, and a mixing speed of 200r / min.

[0116] Example 3:

[0117] According to another preferred embodiment of the present invention, the material selection and proportioning, preparation process, technical principle, and beneficial effects are basically the same as those in Embodiment 1, except that:

[0118] The bio-based asphalt cold patch material comprises, by mass percentage, 96.5 wt% recycled asphalt pavement material and 3.5 wt% bio-based asphalt cold patch liquid. The bio-based asphalt cold patch liquid comprises, by mass percentage, 60 wt% 70# base asphalt, 15 wt% bio-based diluent, and 25 wt% bio-based regenerator.

[0119] The asphalt pavement recycled material comprises twelve particle sizes, with each particle size accounting for the following percentage by mass: 19-26.5mm 6-10wt%, 16-19mm 5-9wt%, 13.2-16mm 5-13wt%, 9.5-13.2mm 8-12wt%, 4.75-9.5mm 15-19wt%, 2.36-4.75mm 12-18wt%, 1.18-2.36mm 6-10wt%, 0.6-1.18mm 5-7wt%, 0.3-0.6mm 5-7wt%, 0.15-0.3mm 5-7wt%, 0.075-0.15mm 2-6wt%, and 0-0.075mm 2-6wt%. The content ranges of each particle size range mentioned above are applicable to this embodiment, and the total content of each particle size range is 100%.

[0120] Specifically, in this embodiment, the following particle sizes are used asphalt: 19-26.5mm (8wt%), 16-19mm (7wt%), 13.2-16mm (9wt%), 9.5-13.2mm (10wt%), 4.75-9.5mm (17wt%), 2.36-4.75mm (15wt%), 1.18-2.36mm (8wt%), 0.6-1.18mm (6wt%), 0.3-0.6mm (6wt%), 0.15-0.3mm (6wt%), 0.075-0.15mm (4wt%), and 0-0.075mm (4wt%). Overall, the recycled asphalt pavement material comprises 35% old asphalt.

[0121] The bio-based diluent comprises the following components by mass percentage: 55 wt% vegetable oil and its derivatives, 25 wt% fatty acids and their esters, 15 wt% natural small-molecule organic compounds, and 5 wt% oxalic acid. The vegetable oil and its derivatives comprise the following components by mass percentage: 70 wt% vegetable oil, 15 wt% epoxidized soybean oil methyl ester, and 15 wt% hydrogenated ricinoleate methyl ester. The fatty acids and their esters comprise the following components by mass percentage: 40 wt% fatty acids and 60 wt% fatty acid esters. The natural small-molecule organic compounds comprise the following components by mass percentage: 85 wt% phytosterols, 5 wt% sucrose fatty acid esters, and 10 wt% limonene.

[0122] The bio-based regenerator comprises the following components by mass percentage: 55 wt% vegetable oil, 12 wt% terpene phenolic resin, 6 wt% antioxidant, 3 wt% surfactant, 6 wt% plasticizer, 6 wt% stabilizer, and 12 wt% bio-based modifier. The amount of bio-based modifier added increases with the amount of vegetable oil added. Within the mass percentage range of the bio-based modifier and vegetable oil, for every 2 wt% increase in the amount of vegetable oil, the amount of bio-based modifier added first increases by 1.2 wt%, then by 1.0 wt%, with each addition controlled within the range of 0.8-1.2 wt%.

[0123] The antioxidant comprises, by weight percentage, 32 wt% dilauryl thiodipropionate, 58 wt% furfural, and 10 wt% vitamin E. The stabilizer comprises, by weight percentage, 42 wt% bentonite, 38 wt% diatomaceous earth, and 20 wt% talc. The bio-based modifier comprises, by weight percentage, 25 wt% algal extract, 45 wt% sulfonated lignin, and 30 wt% chitosan; the algal extract comprises, by weight percentage, 46 wt% spirulina extract, 46 wt% chlorella extract, and 8 wt% brown algae extract.

[0124] The main parameters of the preparation process of the bio-based regenerant include: Step (4), putting vegetable oil into the reaction vessel and heating it, raising the temperature to 70°C at a rate of 5°C / min, and stirring slowly during the heating process; Step (5), maintaining the temperature in the reaction vessel at 70°C, adding surfactant and stirring, and continuing to stir for 8 minutes after dissolution, with a stirring speed of 200 r / min; Step (6), maintaining the temperature in the reaction vessel at 70°C, adding terpene phenolic resin and stirring, and continuing to stir for 8 minutes after dissolution, with a stirring speed of 200 r / min; Step (7), maintaining the temperature in the reaction vessel at 70°C, first Add dilaurate thiodipropionate and vitamin E and stir for 5 min, then add furfural and stir for 120 s at a stirring speed of 200 r / min; in step (8), raise the temperature in the reactor from 70°C to 90°C at a heating rate of 5°C / min, first add chitin and sulfonated lignin and stir for 3 min, then add algae extract and stir for 15 min at a stirring speed of 200 r / min; in step (9), keep the temperature in the reactor at 90°C, add plasticizer and stabilizer and stir for 40 min at a stirring speed of 200 r / min, and the bio-based asphalt regenerator is obtained.

[0125] In step one, the preparation method of the epoxidized soybean oil methyl ester is as follows: epoxidized soybean oil and acetone are added to a flask, with 15g of epoxidized soybean oil and 20% of the mass of epoxidized soybean oil in the acetone; 60mL of methanol solution is added to the flask; the mixture is stirred electromagnetically for 1.5h; after the reaction is completed, the remaining alkaline catalyst and water are removed, and the reaction product is placed in a vacuum oven at 60℃ and dried for 1h to obtain epoxidized soybean oil methyl ester.

[0126] In step one, the preparation method of hydrogenated methyl ricinoleate is as follows: methyl ricinoleate and a copper-nickel bimetallic catalyst are added to a reaction vessel, with 2g of methyl ricinoleate and the copper-nickel bimetallic catalyst accounting for 1.2% of the mass of methyl ricinoleate; the reaction vessel is continuously purged with nitrogen gas at a flow rate of 20L / min for 5min to remove air; hydrogen gas at 2.5MPa is introduced into the reaction vessel, and the temperature is raised to 135℃, and the substances react at this temperature for 10h; after the reaction is completed, the catalyst is removed to obtain hydrogenated methyl ricinoleate.

[0127] In step four, the base asphalt is heated to 175°C in the oven for 1 hour, and then stirred for another 8 minutes after adding the bio-based regenerator.

[0128] In step five, after cooling to 55°C, add the bio-based diluent and continue stirring for 15 minutes.

[0129] In step six, recycled asphalt pavement materials of various particle sizes are placed into a mixing pot for mixing at a temperature of 25±5℃, a mixing time of 150s, and a mixing speed of 100r / min. Bio-based asphalt cold patching liquid is then added to the mixing pot for further mixing at a temperature of 25±5℃, a mixing time of 150s, and a mixing speed of 100r / min.

[0130] In accordance with relevant industry testing specifications and standards, such as the "Test Procedures for Asphalt and Asphalt Mixtures in Highway Engineering (JTG E20-2011)," the "Technical Specifications for Construction of Cold-Patch Asphalt Mixtures for Urban Asphalt Pavements (DB42 / T 1923-2022)," and the "Technical Specifications for Construction of Solvent-Based Cold-Patch Asphalt Mixtures (DB41 / T 1289-2016)," the performance of the bio-based cold-patch asphalt materials prepared in the above three embodiments was tested. The testing equipment, environment, conditions, sample shape, and size were all identical. Three parallel tests were performed for each performance test, and the average value was taken. The test results are shown in Table 1. Among them, the initial strength, molding strength, and adhesion grade were tested according to the method of this embodiment.

[0131] I. Initial Strength

[0132] Test procedure: (1) Weigh a certain amount of bio-based cold patch material and fill it into a Marshall mold at room temperature. Compact it on both sides 75 times. There should be at least 3 specimens per group, and the height of the specimens should meet the requirement of 63.5±1.3mm. The mass of the bio-based cold patch material used in the test is estimated by referring to the following formula: (2) Immediately remove the mold from a set of compacted specimens and perform a Marshall strength test.

[0133] Results processing: When the difference between a data point and the mean in a set of measurements is greater than k times the standard deviation, that measurement should be discarded, and the average of the other measurements should be used as the experimental result. When the number of trials n is 3, 4, 5, and 6, the values ​​of k are 1.15, 1.46, 1.67, and 1.82, respectively. The experimental results are accurate to 0.1 kN.

[0134] II. Molding Strength

[0135] Experimental steps: (1) Weigh a certain amount of bio-based cold-mix material and put it into the mold at room temperature. After compacting both sides 50 times, the height of the specimen and the mold is 63.5±1.3mm. Prepare more than 3 specimens. (2) Place the specimen and the mold together in a 110℃ oven for 24h. After taking it out, compact both sides 25 times to make a Marshall specimen. (3) Place the mold upright at room temperature for 24h. After demolding, cure it in a 60℃ constant temperature water bath for 30min. Perform the Marshall test and test its stability MS.

[0136] Results processing: When the difference between a data point and the mean in a set of measurements is greater than k times the standard deviation, that measurement should be discarded, and the average of the other measurements should be used as the experimental result. When the number of trials n is 3, 4, 5, and 6, the values ​​of k are 1.15, 1.46, 1.67, and 1.82, respectively. The experimental results are accurate to 0.1 kN.

[0137] III. Adhesion Grade

[0138] Weigh 300g of bio-based cold patch material and add it to distilled water at 80℃. Stir with a glass rod at a rate of one revolution per second. After heating and stirring for 20 minutes, spread the cold patch material onto a glass plate and allow it to cool at room temperature for 1 hour. Observe the asphalt peeling of the cold patch material. The optimal adhesion level is 5, meaning that the cold patch film on the RAP surface is completely preserved after the test, and the percentage of peeling area is close to 0.

[0139] Table 1 Performance test results of bio-based asphalt cold patching material

[0140]

[0141] The test results show that the bio-based asphalt cold patching materials prepared in the three examples have good stability, strength (initial strength and molding strength) and adhesion.

[0142] In the above embodiments, all raw materials used in the preparation of the bio-based diluent, epoxidized soybean oil methyl ester, hydrogenated castor oil methyl ester, and copper-nickel bimetallic catalyst were purchased from Aladdin Reagent Co., Ltd.; the matrix asphalt was purchased from Beijing Municipal Road & Bridge Building Materials Group Co., Ltd. The algal extracts (spirulina extract, chlorella extract, and brown algae extract) used in the preparation of the bio-based regenerator were purchased from Xi'an Tianguangyuan Biotechnology Co., Ltd.; the terpene phenolic resin was purchased from Arakawa Chemical Synthesis (Shanghai) Co., Ltd.; and chitin, sulfonated lignin, vegetable oil, bentonite, diatomaceous earth, talc, epoxidized soybean oil, dodecyl dimethyl ammonium bromide, dilauryl thiodipropionate, furfural, vitamin E, and other substances were purchased from Aladdin Reagent Co., Ltd. All of the above raw materials can also be purchased from other reputable manufacturers on the market.

[0143] Special Note: The technical solution of this invention involves numerous parameters, and the synergistic effects between these parameters must be comprehensively considered to achieve the beneficial effects and significant progress of this invention. Furthermore, the value ranges of each parameter in the technical solution were obtained through extensive experimentation. For each parameter and the combinations thereof, the inventors have recorded a large amount of experimental data; however, due to space limitations, the specific experimental data is not disclosed here.

[0144] It will be readily understood by those skilled in the art that this invention includes any combination of the inventive description and specific embodiments outlined in the foregoing specification and the various parts shown in the accompanying drawings. Due to space limitations and for the sake of brevity, not all of these combinations have been described in detail. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A room-temperature bio-based asphalt cold patching material, characterized in that, The bio-based asphalt cold patch material comprises, by mass percentage, 96.5-98 wt% recycled asphalt pavement material and 2-3.5 wt% bio-based asphalt cold patch liquid. The bio-based asphalt cold patch liquid comprises, by mass percentage, 60-70 wt% base asphalt, 10-20 wt% bio-based diluent, and 20-30 wt% bio-based regenerator. The bio-based diluent comprises the following components by mass percentage: 40-60 wt% vegetable oil and its derivatives, 25-40 wt% fatty acids and their esters, 10-20 wt% natural small molecule organic compounds, and 5-8 wt% carrageenan. The mass percentage of each substance in the vegetable oil and its derivative components is 60-70 wt% vegetable oil, 15-20 wt% epoxidized soybean oil methyl ester, and 15-20 wt% hydrogenated ricinoleate methyl ester; the vegetable oil is any one or more of soybean oil, sunflower seed oil, corn oil, tung oil, and linseed oil. The mass percentage of each substance in the natural small molecule organic component is 75-85 wt% phytosterols, 5-10 wt% sucrose fatty acid esters, and 10-15 wt% limonene; the phytosterols are any one or more of β-sitosterol, brassosterol, and stigmasterol. The bio-based regenerator comprises the following components by mass percentage: 47-55 wt% vegetable oil, 12-16 wt% terpene phenolic resin, 5-8 wt% antioxidant, 3-5 wt% surfactant, 6-8 wt% plasticizer, 6-8 wt% stabilizer, and 8-12 wt% bio-based modifier. The amount of bio-based modifier increases with the amount of vegetable oil added. Within the mass percentage range of the bio-based modifier and vegetable oil, for every 2 wt% increase in the amount of vegetable oil, the amount of bio-based modifier increases by 0.8-1.2 wt%. The bio-based modifier comprises, by mass percentage, algal extract 18-25 wt%, sulfonated lignin 45-55 wt%, and chitin 27-32 wt%; and the algal extract comprises, by mass percentage, spirulina extract 42-48 wt%, chlorella extract 42-48 wt%, and brown algae extract 8-15 wt%.

2. The ambient temperature bio-based cold patching material according to claim 1, characterized in that, The recycled asphalt pavement material comprises nine particle sizes, with each particle size accounting for the following percentage by mass: 9.5-13.2mm 6-10wt%, 4.75-9.5mm 15-23wt%, 2.36-4.75mm 25-33wt%, 1.18-2.36mm 15-19wt%, 0.6-1.18mm 5-9wt%, 0.3-0.6mm 3-7wt%, 0.15-0.3mm 3-7wt%, 0.075-0.15mm 3-7wt%, and 0-0.075mm 3-7wt%. Alternatively, the asphalt pavement recycled material comprises ten particle size grades, with each particle size grade accounting for the following mass percentage of the asphalt pavement recycled material: 13.2-16mm 6-10wt%, 9.5-13.2mm 20-24wt%, 4.75-9.5mm 15-25wt%, 2.36-4.75mm 10-18wt%, 1.18-2.36mm 8-12wt%, 0.6-1.18mm 3-7wt%, 0.3-0.6mm 3-7wt%, 0.15-0.3mm 3-7wt%, 0.075-0.15mm 5-7wt%, and 0-0.075mm 3-7wt%. Alternatively, the asphalt pavement recycled material comprises twelve particle sizes, with each particle size accounting for the following percentage by mass: 19-26.5mm 6-10wt%, 16-19mm 5-9wt%, 13.2-16mm 5-13wt%, 9.5-13.2mm 8-12wt%, 4.75-9.5mm 15-19wt%, 2.36-4.75mm 12-18wt%, 1.18-2.36mm 6-10wt%, 0.6-1.18mm 5-7wt%, 0.3-0.6mm 5-7wt%, 0.15-0.3mm 5-7wt%, 0.075-0.15mm 2-6wt%, and 0-0.075mm 2-6wt%. The main components of the recycled asphalt pavement material are old asphalt and old aggregate. The outer surface of the old aggregate is partially or completely covered with old asphalt, and the proportion of old asphalt is 25-35% overall.

3. The ambient temperature bio-based cold patching material according to claim 2, characterized in that, The fatty acid and its ester components comprise, by mass percentage, 30-40 wt% fatty acid and 60-70 wt% fatty acid esters; the fatty acid is any one or more of oleic acid, linoleic acid, and stearic acid, and the fatty acid ester is any one or more of methyl oleate, ethyl oleate, propyl oleate, methyl linoleate, ethyl linoleate, and glyceryl stearate.

4. A method for preparing a room-temperature bio-based cold patching asphalt, characterized in that, The method for preparing the ambient temperature bio-based cold patch asphalt according to any one of claims 1-3 includes the following steps in sequence: Step 1: Prepare epoxidized soybean oil methyl ester and hydrogenated castor oil methyl ester according to the designed process parameters; Step 2: Weigh each raw material according to the designed material ratio and set aside; Step 3: Mix vegetable oil, epoxidized soybean oil methyl ester, and hydrogenated ricinoleate methyl ester at room temperature according to the designed material ratio to obtain vegetable oil and its derivative components; mix fatty acids and fatty acid esters at room temperature according to the designed material ratio to obtain fatty acids and their ester components; mix phytosterols, sucrose fatty acid esters, and limonene at room temperature according to the designed material ratio to obtain natural small molecule organic components; mix vegetable oil and its derivative components, fatty acids and their ester components, natural small molecule organic components, and oxalic acid at room temperature according to the designed material ratio to obtain a bio-based diluent. Step 4: Place the base asphalt into a container, then place the container containing the base asphalt into an oven and heat it until the base asphalt becomes fluid. After heating, remove the container containing the fluid base asphalt from the oven, and add the bio-based regenerator while stirring. After adding the bio-based regenerator, continue stirring to ensure that it is completely dissolved. Step 5: After the bio-based regenerator is completely dissolved, stir and cool down. After cooling to a certain temperature, add the bio-based diluent while stirring. After the addition is completed, continue stirring to make the bio-based diluent completely dissolved, thus obtaining the bio-based asphalt cold patching solution. Step Six: According to the designed material ratio, put the recycled asphalt pavement materials of each particle size into the mixing pot and mix them. After the mixing is completed, add the bio-based asphalt cold patch liquid into the mixing pot and continue mixing to obtain the bio-based asphalt cold patch material.

5. The preparation method of the room-temperature bio-based cold patching material according to claim 4, characterized in that, In step one, the preparation method of the epoxidized soybean oil methyl ester is as follows: epoxidized soybean oil and acetone are added to a 100mL flask, with the amount of epoxidized soybean oil being 10-15g and the amount of acetone being 15-20% of the amount of epoxidized soybean oil; 50-60mL of a methanol solution with an alkali concentration of 0.05mol / L is added to the flask; the mixture of epoxidized soybean oil, acetone, and methanol is electromagnetically stirred at room temperature for 1-1.5h; after the reaction is completed, the reaction product is washed with deionized water to remove the remaining alkali catalyst, and then the remaining water is removed with anhydrous sodium sulfate; the reaction product is dried in a vacuum oven at 50-60℃ for 1-2h to obtain epoxidized soybean oil methyl ester.

6. The method for preparing room-temperature bio-based cold patching asphalt according to claim 5, characterized in that, In step one, the preparation method of hydrogenated methyl ricinoleate is as follows: methyl ricinoleate and a copper-nickel bimetallic catalyst are added to a reaction vessel. The amount of methyl ricinoleate added is 1-2g, and the amount of the copper-nickel bimetallic catalyst added is 0.8-1.2% of the amount of methyl ricinoleate added. The reaction vessel is continuously purged with nitrogen gas at a flow rate of 5-20L / min for 5-8min to replace the air in the reaction vessel. Hydrogen gas at 2-2.5MPa is introduced into the reaction vessel, and the temperature is raised to 125-135℃. The substances in the reaction vessel react at this temperature for 10-12h. After the reaction is completed, the reaction product is washed with ethyl acetate to remove the catalyst, thereby obtaining hydrogenated methyl ricinoleate.

7. The preparation method of the room-temperature bio-based cold patching asphalt according to claim 6, characterized in that, In step four, the base asphalt is heated to 155-175℃ in the oven for 1-2 hours, and then stirred for 5-8 minutes after adding the bio-based regenerator.

8. The method for preparing room-temperature bio-based cold patching asphalt according to claim 7, characterized in that, In step five, after cooling to 45-55℃, add the bio-based diluent and continue stirring for 10-15 minutes.

9. The preparation method of the room-temperature bio-based cold patching asphalt according to claim 8, characterized in that, In step six, recycled asphalt pavement materials of various particle sizes are placed into a mixing pot for mixing at a temperature of 25±5℃, a mixing time of 90-150s, and a mixing speed of 100-200r / min. Bio-based asphalt cold patching liquid is then added to the mixing pot for further mixing at a temperature of 25±5℃, a mixing time of 90-150s, and a mixing speed of 100-200r / min.

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