Energy-saving emulsified asphalt mixture and preparation method thereof

Abstract

The application discloses an energy-saving emulsified asphalt mixture and a preparation method thereof, and belongs to the field of road engineering materials. The energy-saving emulsified asphalt mixture is prepared from petroleum asphalt, polymeric condensed polycyclic aromatic hydrocarbon amide, citric acid fatty acid glyceride, acrylic acid (ester) / behenyl alcohol polyether-25 methacrylate copolymer, hydrochloric acid solution, curing modifier, aggregate, filler, admixture and the like in a specific proportion. Compared with the prior art, the asphalt mixture has the characteristics of low mixing and construction temperature, excellent road performance and the like.

Description

Technical Field

[0001] This invention relates to the field of road engineering materials, specifically providing an energy-saving emulsified asphalt mixture and its preparation method. Background Technology

[0002] Asphalt pavement is widely used in high-grade roads and urban roads due to its comfortable driving experience, strong load-bearing capacity, and high safety. Currently, the main material used for asphalt pavement is hot-mix asphalt mixture, which requires heating the aggregate to above 160℃, heating the asphalt to 150℃, and ensuring the discharge temperature of the mixture is above 150℃.

[0003] Currently, reducing the mixing temperature of asphalt mixtures is the most effective way to achieve energy conservation and emission reduction. Emulsified asphalt, due to its ease of construction, energy efficiency, and environmental friendliness, can significantly reduce the construction temperature of asphalt mixtures and is widely used in road construction and maintenance. However, traditional emulsified asphalt has a low asphalt content, generally 50-60%, and a high water content, often above 40%. The water in mixtures prepared with it evaporates slowly, resulting in a slow strength formation time and a long curing time, generally more than a week. Furthermore, the high porosity of emulsified asphalt mixtures can, to some extent, affect the road performance of the mixture. Summary of the Invention

[0004] The present invention addresses the shortcomings of the prior art by providing an energy-saving emulsified asphalt mixture that can be mixed at low temperatures and has excellent road performance.

[0005] A further technical objective of this invention is to provide a method for preparing the above-mentioned emulsified asphalt mixture.

[0006] The technical solution adopted by this invention to solve its technical problem is: an energy-saving emulsified asphalt mixture, which is prepared from the following raw materials in the following weight ratio:

[0007]

[0008] The high-solids-content emulsified asphalt, by weight percentage, is made from the following raw materials:

[0009]

[0010] The polycyclic aromatic hydrocarbon amide is composed of polycyclic aromatic hydrocarbon-12 amide and polycyclic aromatic hydrocarbon-16 amide.

[0011] Preferably, the weight ratio of each raw material in the energy-saving emulsified asphalt mixture of the present invention is as follows:

[0012]

[0013] Preferably, the raw material composition of the high-solids-content emulsified asphalt is as follows:

[0014]

[0015] The polycyclic aromatic hydrocarbon amide is composed of polycyclic aromatic hydrocarbon-12 amide and polycyclic aromatic hydrocarbon-16 amide.

[0016] Preferably, the petroleum asphalt is AH-70 asphalt and / or AH-90 asphalt. Petroleum asphalt is the main component of high-solids-content emulsified asphalt, accounting for more than 80 wt%, which allows the performance advantages of asphalt to be fully utilized, and the emulsification process has less impact on the performance of asphalt.

[0017] Preferably, the mass ratio of polycyclic aromatic hydrocarbon-12 amide to polycyclic aromatic hydrocarbon-16 amide is (0.25-1.5):(0.25-1.5), and particularly preferably (0.5-1):(0.5-1). Polycyclic aromatic hydrocarbon-12 amide and polycyclic aromatic hydrocarbon-16 amide are dissolved in acidic water and asphalt, respectively, and work together to reduce interfacial tension. Since the polycyclic aromatic hydrocarbon carboxylic acid used to prepare the amides is obtained by oxidizing petroleum asphalt with a strong acid, these amides have a similar molecular structure to petroleum asphalt, allowing for better dissolution and dispersion in asphalt, thus enhancing their ability to reduce interfacial tension. Furthermore, the polycyclic aromatic hydrocarbon carboxylic acid obtained from the oxidation of asphalt has a molecular structure with polycyclic aromatic hydrocarbon as the core and multiple carboxylic acid groups connected around it. Therefore, the amide prepared is a multi-headed amide structure with polycyclic aromatic hydrocarbon as the core and multiple amide chains connected around it. On the one hand, it exhibits a strong ability to reduce interfacial tension. On the other hand, after protonation under acidic conditions, it carries the same positive charge and has a strong repulsive force between molecules, making it difficult for asphalt droplets to aggregate, thus enabling it to exist stably in the form of an emulsion.

[0018] Preferably, the polycyclic aromatic hydrocarbon-12 amide is generated by an amidation reaction of polycyclic aromatic hydrocarbon carboxylic acid and dodecylamine, wherein the polycyclic aromatic hydrocarbon carboxylic acid is obtained by oxidizing asphalt with a strong acid.

[0019] Preferably, the polycyclic aromatic hydrocarbon-16 amide is generated by an amidation reaction of polycyclic aromatic hydrocarbon carboxylic acid and hexadecylamine, and the polycyclic aromatic hydrocarbon carboxylic acid is obtained by oxidizing asphalt with a strong acid.

[0020] Preferably, the preparation method of polycyclic aromatic hydrocarbon-12 amide or polycyclic aromatic hydrocarbon-16 amide includes:

[0021] (1) The asphalt was chemically oxidized with a strong acid, and after separation and purification, polycyclic aromatic carboxylic acid was obtained.

[0022] (2) After adding polycyclic aromatic hydrocarbon carboxylic acid, dodecylamine or hexadecylamine, catalyst and solvent to the reaction vessel, seal the reaction vessel and replace the gas inside the vessel with N2;

[0023] (3) When the temperature inside the reactor reaches 160-180℃, turn on the stirring device and continue heating to 210-230℃. Maintain this temperature and pressure for 1-2 hours, then release the steam for 2-3 hours, and continue the reaction under vacuum for 3-5 hours. After the reaction is completed, lower the temperature to room temperature to obtain the crude product.

[0024] (4) The crude product was washed and filtered with acetone and then dried under vacuum to obtain polycyclic aromatic hydrocarbon-12 amide or polycyclic aromatic hydrocarbon-16 amide final product.

[0025] Preferably, the strong acid in step (1) is concentrated nitric acid.

[0026] Preferably, the asphalt in step (1) is hard asphalt. Compared with ordinary base asphalt, hard asphalt has a higher content of resins and asphaltenes, and a higher content of polycyclic aromatic hydrocarbons. Using it as a raw material for strong acid oxidation can yield more polycyclic aromatic carboxylic acids.

[0027] During the oxidation reaction, asphalt and concentrated nitric acid are mixed at a mass ratio of 1:(5-15), heated to 80-95℃ with stirring, and refluxed for 3-5 hours. After the reaction is complete, the mixture is cooled to room temperature and diluted with distilled water. The solution is then filtered through a 0.2-micron microporous membrane, and the remaining nitric acid in the filtrate is removed by vacuum distillation to obtain polycyclic aromatic hydrocarbon carboxylic acid. Further, the preferred mass ratio of asphalt to concentrated nitric acid is 1:(8-12); the preferred oxidation reaction temperature is 85-95℃.

[0028] Preferably, the catalyst in step (2) is sodium hypophosphite and the solvent is sulfolane.

[0029] The mass ratio of polycyclic aromatic carboxylic acid to dodecylamine (or hexadecylamine) is 1:(2-5); the amount of catalyst added is 0.5-2% of the total mass of polycyclic aromatic carboxylic acid and dodecylamine (or hexadecylamine).

[0030] Preferably, the stirring speed in step (3) is 50-70 r / min, and more preferably 55-65 r / min.

[0031] Preferably, the vacuum drying temperature in step (4) is 60-80℃, and more preferably 65-75℃.

[0032] Preferably, the hydrochloric acid solution has a pH of 1-4, and more preferably 1-2.

[0033] Preferably, the method for preparing the high-solids-content emulsified asphalt includes the following steps:

[0034] A1. Add polycyclic aromatic hydrocarbon-12 amide, citric acid fatty acid glyceride, and acrylate / behenol polyether-25 methacrylate copolymer to a hot hydrochloric acid solution, stir evenly, and cool to obtain soap solution for later use.

[0035] A2. Polycyclic aromatic hydrocarbon-16 amide is added to hot asphalt and stirred evenly to obtain an activated asphalt mixture for later use;

[0036] A3. Quickly add the soap solution obtained in step A1 to the activated asphalt mixture obtained in step A2, and continue stirring for a certain period of time to obtain high solids content emulsified asphalt.

[0037] Preferably, in step A1, the temperature of the hot hydrochloric acid solution is 70-80℃, the temperature of the soap solution is 50-60℃, and the stirring rate is preferably 300-500 r / min. The specific method is as follows:

[0038] Heat water to 70-80℃, add hydrochloric acid to adjust the pH of the water to about 1-4, then add polycyclic aromatic hydrocarbon-12 amide, citric acid fatty acid glyceride, and acrylic (ester) / behenol polyether-25 methacrylate copolymer, stir evenly, and then cool to 50-60℃ under natural conditions to obtain soap solution.

[0039] Preferably, in step A2, the temperature of the hot asphalt is 110-130℃, and the stirring rate is 1000-2000 r / min. The specific method is as follows:

[0040] The asphalt is heated to 110-130℃, and then polycyclic aromatic hydrocarbon-16 amide is added. The mixture is stirred at 1000-2000 r / min for 5-10 min to obtain an activated asphalt mixture, which is then maintained at this temperature. The stirring rate is particularly preferably 1000-1500 r / min.

[0041] Preferably, in step A3, the soap solution and activated asphalt mixture are stirred for 10-20 minutes at 110-130°C and a stirring rate of 800-1500 r / min to obtain high-solids-content emulsified asphalt. The stirring rate is particularly preferably 800-1200 r / min.

[0042] Preferably, the curing modifier is a moisture-curing single-component polyurethane.

[0043] Preferably, the filler is mineral powder.

[0044] Preferably, the admixture is quicklime, anhydrous sodium sulfate, and / or cement.

[0045] The present invention relates to a method for preparing energy-saving emulsified asphalt mixtures, characterized in that, under stirring conditions, coarse and fine aggregates, curing modifiers, high-solids-content emulsified asphalt, fillers, and admixtures are sequentially added to a mixing pot and stirred until homogeneous. The temperature of the coarse and fine aggregates is 100-120℃, the temperature of the high-solids-content emulsified asphalt is 60-80℃, and the stirring speed is 1000-2000 r / min.

[0046] Preferably, the method for preparing the mixture is as follows:

[0047] S1. Add the coarse and fine aggregates heated to 100-120℃ into the mixing pot and stir for 10-60 seconds;

[0048] S2. Add the curing modifier to the mixing pot and stir for 10-60 seconds;

[0049] S3. Add the high-solids-content emulsified asphalt heated to 60-80℃ into the mixing pot and stir for 60-120 seconds;

[0050] S4. Add filler and admixtures, and continue stirring for 60-120 seconds to obtain energy-saving emulsified asphalt mixture.

[0051] Compared with existing technologies, the energy-saving emulsified asphalt mixture of the present invention has the following outstanding advantages:

[0052] (i) Polycyclic aromatic hydrocarbon amides are prepared by amidation reaction of asphalt with long-chain fatty amines after strong acid oxidation. They have similar structures to asphalt components and can be better dispersed in asphalt. They also contain multiple amide groups, which can better reduce interfacial tension. In addition, the hydrophilic segments are protonated and carry the same positive charge, which prevents the aggregation of asphalt particles and maintains the stability of the emulsion.

[0053] (II) Polycyclic aromatic hydrocarbon amides are composed of both oil-soluble and water-soluble materials. Water-soluble polycyclic aromatic hydrocarbon amides, when added to water, dissolve and protonate under acidic conditions. They work synergistically with citric acid fatty acid glyceride nonionic emulsifiers to reduce interfacial tension and form mixed micelles, achieving an additive and synergistic effect. Oil-soluble polycyclic aromatic hydrocarbon amides dissolve in asphalt, reducing the surface tension of the asphalt and thus activating it. Under the synergistic effect of oil-soluble and water-soluble polycyclic aromatic hydrocarbon amides, the interfacial tension between asphalt and water can be significantly reduced, allowing asphalt to disperse in water under relatively "low-energy" conditions.

[0054] (III) The applicant discovered that acrylate / behenol polyether-25 methacrylate copolymer exhibits excellent dispersibility in high-solids-content emulsified asphalt, demonstrating enhanced thickening ability and providing the emulsion with a certain degree of elastic recovery. It works synergistically with emulsifiers to stabilize high-solids-content emulsified asphalt. Simultaneously, this substance can form a thin film on the surface of the high-internal-phase emulsion, providing protection and sealing, helping to "lock in" moisture and prevent moisture loss. This avoids demulsification and phase inversion caused by the loss of small amounts of moisture in the high-solids-content emulsified asphalt due to evaporation.

[0055] (iv) The high-solids-content emulsified asphalt is prepared using a stirring method. Traditional emulsified asphalt preparation processes involve dispersing asphalt into soap solution using high-speed shearing and grinding to form emulsified asphalt. However, the asphalt content in this process generally does not exceed 70%. Exceeding this limit may cause the emulsified asphalt to reverse, resulting in a sharp increase in viscosity that the emulsification equipment cannot withstand, forcing it to stop operating. This invention, through the synergistic effect of selected polycyclic aromatic hydrocarbon amides, citric acid fatty acid glycerides, and acrylate / behenol polyether-25 methacrylate copolymers, adds soap solution to the asphalt in one step under stirring. The water instantly vaporizes, breaking the oil-water interfacial tension, causing the asphalt to foam. This reduces the viscosity of the system, and the asphalt disperses into the water under stirring, forming an oil-in-water emulsion. This significantly reduces preparation costs while obtaining high-quality emulsified asphalt.

[0056] (V) During use, the curing modifier is first added to the aggregate. After stirring, it spreads evenly on the aggregate surface, forming a thin film. Because the isocyanate groups on the surface of the curing modifier are fully exposed, they undergo a cross-linking and curing reaction with the water in the high-solids-content emulsified asphalt added later, as well as the polar functional groups on the asphalt surface, forming a substance with strong adhesive properties. This improves the adhesion between asphalt and aggregate and its high-temperature stability. Furthermore, because the reaction consumes the water in the high-solids-content emulsified asphalt, it avoids the problem of insufficient road performance of the asphalt mixture due to the presence of water. In addition, the reaction between the curing modifier and water is a gradual and slow process; sufficient reaction time ensures the workability and ease of construction of the mixture.

[0057] (vi) Compared with existing hot-mix asphalt mixtures, the energy-saving emulsified asphalt mixture of the present invention can reduce the mixing and construction temperature by more than 40°C, with good energy-saving and emission-reduction effects. There are no toxic and harmful gas emissions during the construction process, making it environmentally friendly. It not only does not reduce the road performance of the asphalt mixture, but also improves its high-temperature performance, with a rutting dynamic stability of more than 2000 times / mm.

[0058] (vii) Compared with traditional emulsified asphalt mixtures, traffic can be opened immediately after construction without the need for curing. Attached Figure Description

[0059] Appendix Figure 1 This is a diagram showing the mixing state of the emulsified asphalt mixture in Example 3;

[0060] Appendix Figure 2 This is the cut surface of the emulsified asphalt mixture after molding in Example 4. Detailed Implementation

[0061] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the present invention.

[0062] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0063] Material descriptions for various embodiments of the present invention:

[0064] AH-70 petroleum asphalt: penetration 64 (0.1 mm), softening point 47.5℃, ductility at 10℃ > 100 cm;

[0065] AH-90 petroleum asphalt: penetration 85 (0.1 mm), softening point 45.5℃, ductility at 10℃ > 100 cm;

[0066] Hydrochloric acid: chemically pure, concentration 38%;

[0067] Curing modifier: Moisture-curing one-component polyurethane;

[0068] Filler: mineral powder;

[0069] Coarse and fine aggregates: limestone AC-13C gradation, see Table 1 for specific gradation.

[0070] Table 1. Percentage of mass passing through the following sieve openings (square hole sieve)

[0071]

[0072]

Example 1

[0073] This embodiment discloses an energy-saving emulsified asphalt mixture, which is prepared by the following steps:

[0074] 1. Preparation of high solids content emulsified asphalt

[0075] Raw materials and proportions:

[0076] AH-70 petroleum asphalt 82wt%, polycyclic aromatic hydrocarbon acyl-16 amide 1.0wt%, polycyclic aromatic hydrocarbon acyl-12 amide 1.0wt%, citric acid fatty acid glyceride 2.0wt%, acrylic (ester) / behenol polyether-25 methacrylate copolymer 0.5wt%, hydrochloric acid 0.2%, water 13.3wt%.

[0077] Preparation method:

[0078] A1. Heat water to 70℃, add hydrochloric acid, and adjust the pH of the water to 2.0-2.2. Then slowly add polycyclic aromatic hydrocarbon-12 amide, citric acid fatty acid glyceride, and acrylate / behenol polyether-25 methacrylate copolymer. Stir at 400r / min for 15min, add hydrochloric acid to adjust the pH to 2.0-2.2, stir evenly, and then cool to 60℃ under natural conditions to obtain soap solution for later use.

[0079] A2. Heat the asphalt to 110°C, then add polycyclic aromatic hydrocarbon-16 amide, and stir at 1000 r / min for 8 min to obtain an activated asphalt mixture. Maintain this temperature for later use.

[0080] A3. At the temperature and stirring rate described in step A2, the soap solution obtained in step A1 is quickly added to the activated asphalt mixture described in step A2 in one go, and stirring is continued for 10 minutes at a speed of 1000 r / min to obtain high solids content emulsified asphalt.

[0081] 2. Preparation of energy-saving emulsified asphalt mixture

[0082] Raw materials and proportions:

[0083] The composition consists of 89.2 wt% coarse and fine aggregates, 1.0 wt% curing modifier, 3.0 wt% filler, 1.0 wt% quicklime, 1.0 wt% anhydrous sodium sulfate, and 4.8 wt% high-solids emulsified asphalt.

[0084] Preparation method:

[0085] S1. Add the coarse and fine aggregates heated to 110℃ into the mixing pot and stir for 30 seconds;

[0086] S2. Add the curing modifier to the mixing pot and stir for 30 seconds;

[0087] S3. Add the high-solids-content emulsified asphalt heated to 70℃ into the mixing pot and stir for 90 seconds;

[0088] S4. Add filler, quicklime and anhydrous sodium sulfate and stir for 90 seconds to obtain energy-saving emulsified asphalt mixture.

[0089]

Example 2

[0090] This embodiment discloses an energy-saving emulsified asphalt mixture, which is prepared by the following steps:

[0091] 1. Preparation of high solids content emulsified asphalt

[0092] Raw materials and proportions:

[0093] The raw materials and formulation of high-solids-content emulsified asphalt are as follows: 88wt% AH-70 petroleum asphalt, 1.0wt% polycyclic aromatic hydrocarbon acyl-16 amide, 1.0wt% polycyclic aromatic hydrocarbon acyl-12 amide, 2.0wt% citric acid fatty acid glyceride, 0.5wt% acrylic (ester) / behenol polyether-25 methacrylate copolymer, 0.2% hydrochloric acid, and 7.3wt% water.

[0094] Preparation method:

[0095] The preparation method of high solids content emulsified asphalt in this embodiment is the same as in Embodiment 1.

[0096] 2. Preparation of energy-saving emulsified asphalt mixture

[0097] Raw materials and proportions:

[0098] The composition consists of 88.7 wt% coarse and fine aggregates, 0.5 wt% curing modifier, 4.0 wt% filler, 1.0 wt% quicklime, 1.0 wt% anhydrous sodium sulfate, and 4.8 wt% high-solids emulsified asphalt.

[0099] Preparation method:

[0100] The preparation method of the energy-saving emulsified asphalt mixture in this embodiment is the same as that in Embodiment 1.

[0101]

Example 3

[0102] This embodiment discloses an energy-saving emulsified asphalt mixture, which is prepared by the following steps:

[0103] 1. Preparation of high solids content emulsified asphalt

[0104] The raw material ratio and preparation method of the high solids content asphalt emulsified asphalt in this embodiment are the same as those in Embodiment 2.

[0105] 2. Preparation of energy-saving emulsified asphalt mixture

[0106] Raw materials and proportions:

[0107] The composition consists of 91.2 wt% coarse and fine aggregates, 1.0 wt% filler, 2.0 wt% curing modifier, 0.5 wt% quicklime, 0.5 wt% anhydrous sodium sulfate, and 4.8 wt% high-solids emulsified asphalt.

[0108] Preparation method:

[0109] The preparation method of the energy-saving emulsified asphalt mixture in this embodiment is the same as that in Embodiment 1.

[0110] From the appendix Figure 1 It can be seen that the mixture in the mixing pot is well mixed.

[0111]

Example 4

[0112] This embodiment discloses an energy-saving emulsified asphalt mixture, which is prepared by the following steps:

[0113] 1. Preparation of high solids content emulsified asphalt

[0114] The raw material ratio and preparation method of the high solids content asphalt emulsified asphalt in this embodiment are the same as those in Embodiment 2.

[0115] 2. Preparation of energy-saving emulsified asphalt mixture

[0116] Raw materials and proportions:

[0117] The composition consists of 89.2 wt% coarse and fine aggregates, 3.0 wt% filler, 1.0 wt% curing modifier, 2.0 wt% quicklime, and 4.8 wt% high-solids emulsified asphalt.

[0118] Preparation method:

[0119] The preparation method of the energy-saving emulsified asphalt mixture in this embodiment is the same as that in Embodiment 1.

[0120] After compaction, the resulting mixture has a dense cross-section and good compaction (e.g., Figure 2 (As shown).

[0121]

Example 5

[0122] This embodiment discloses an energy-saving emulsified asphalt mixture, which is prepared by the following steps:

[0123] 1. Preparation of high solids content emulsified asphalt

[0124] The raw material ratio and preparation method of the high solids content asphalt emulsified asphalt in this embodiment are the same as those in Embodiment 1.

[0125] 2. Preparation of energy-saving emulsified asphalt mixture

[0126] Raw materials and proportions:

[0127] The composition consists of 88.8 wt% coarse and fine aggregates, 3.0 wt% filler, 1.0 wt% curing modifier, 1.0 wt% quicklime, 1.0 wt% anhydrous sodium sulfate, and 5.2 wt% high-solids emulsified asphalt.

[0128] Preparation method:

[0129] The preparation method of the energy-saving emulsified asphalt mixture in this embodiment is the same as that in Embodiment 1.

[0130]

Example 6

[0131] This embodiment discloses an energy-saving emulsified asphalt mixture, which is prepared by the following steps:

[0132] 1. Preparation of high solids content emulsified asphalt

[0133] Raw materials and proportions:

[0134] The raw materials and formulation of high-solids-content emulsified asphalt are as follows: 86wt% AH-70 petroleum asphalt, 1.0wt% polycyclic aromatic hydrocarbon acyl-16 amide, 1.0wt% polycyclic aromatic hydrocarbon acyl-12 amide, 2.0wt% citric acid fatty acid glyceride, 0.5wt% acrylic (ester) / behenol polyether-25 methacrylate copolymer, 0.2% hydrochloric acid, and 9.3wt% water.

[0135] Preparation method:

[0136] The method for preparing high-solids-content emulsified asphalt in this embodiment is the same as in Example 1.

[0137] 2. Preparation of energy-saving emulsified asphalt mixture

[0138] Raw materials and proportions:

[0139] The composition consists of 89.0 wt% coarse and fine aggregates, 3.0 wt% filler, 1.0 wt% curing modifier, 1.0 wt% quicklime, 1.0 wt% anhydrous sodium sulfate, and 5.0 wt% high-solids emulsified asphalt.

[0140] Preparation method:

[0141] The preparation method of the energy-saving emulsified asphalt mixture in this embodiment is the same as that in Embodiment 1.

[0142]

Example 7

[0143] This embodiment discloses an energy-saving emulsified asphalt mixture, which is prepared by the following steps:

[0144] 1. Preparation of high solids content emulsified asphalt

[0145] Raw materials and proportions:

[0146] AH-90 petroleum asphalt 88wt%, polycyclic aromatic hydrocarbon acyl-16 amide 1.0wt%, polycyclic aromatic hydrocarbon acyl-12 amide 1.0wt%, citric acid fatty acid glyceride 2.0wt%, acrylic (ester) / behenol polyether-25 methacrylate copolymer 0.5wt%, hydrochloric acid 0.2%, water 7.3wt%.

[0147] Preparation method:

[0148] The method for preparing high-solids-content emulsified asphalt in this embodiment is the same as in Example 1.

[0149] 2. Preparation of energy-saving emulsified asphalt mixture

[0150] Raw materials and proportions:

[0151] The composition consists of 89.2 wt% coarse and fine aggregates, 3.0 wt% filler, 1.0 wt% curing modifier, 1.0 wt% quicklime, 1.0 wt% anhydrous sodium sulfate, and 4.8 wt% high-solids emulsified asphalt.

[0152] Preparation method:

[0153] The preparation method of the energy-saving emulsified asphalt mixture in this embodiment is the same as that in Embodiment 1.

[0154] [Test Example]

[0155] According to the "Test Procedures for Asphalt and Asphalt Mixtures in Highway Engineering" (JTGE20-2011), the high solids content emulsified asphalt of Examples 1-7 of this invention was tested for properties such as sieve residue, apparent viscosity, evaporation residue content, penetration, softening point, and ductility.

[0156] The conductivity and particle size of high-solids-content emulsified asphalt in water were determined using a conductivity meter and particle size analyzer to assess its long-term storage stability. During the test, 1g of high-solids-content emulsified asphalt was dispersed in 100ml of water. First, the dispersion state of the high-solids-content emulsified asphalt in water was determined. If it could disperse in water, it indicated that water was the continuous phase, forming an oil-in-water emulsion. Then, the conductivity of the aqueous solution was measured using a conductivity meter. Since the conductivity of pure water and asphalt is close to zero, while the conductivity of soap solution is approximately 1600 μS / cm, if high-solids-content emulsified asphalt could disperse in asphalt, the conductivity value should be much greater than zero.

[0157] The initial particle size (1d) was used to determine the emulsification effect of high-solids-content emulsified asphalt; the smaller the particle size, the better the emulsification effect. Since the demulsification process of emulsified asphalt is a process of gradual increase in particle size, the 30d particle size was further used to determine the storage stability of emulsified asphalt by the particle size growth rate.

[0158] The performance of the emulsified asphalt mixtures of Examples 1-7 of this invention was analyzed according to the "Test Procedures for Asphalt and Asphalt Mixtures in Highway Engineering" (JTGE20-2011). The test results are shown in Tables 2 and 3.

[0159] Table 2 Performance Indicators of Emulsified Asphalt

[0160]

[0161] Table 3 Performance of the Mixture

[0162]

[0163] As can be seen from the test data in Tables 2 and 3, the evaporation residue content of the emulsified asphalt in each embodiment is as high as 84% ​​or more, exhibiting excellent storage stability. The high asphalt content allows the emulsified asphalt of this invention to produce mixtures with lower porosity, and all road performance characteristics of the emulsified asphalt mixtures obtained in each embodiment exceed the standard requirements, with a significant improvement in high-temperature performance and a rutting dynamic stability of over 2000 cycles / mm.

[0164] Obviously, the above embodiments are merely examples for clear illustration and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. An emulsified asphalt mixture, characterized in that, It is prepared from the following raw materials in the following weight ratio: 3-6 parts of high-solids-content emulsified asphalt. 0.5-3 parts of curing modifier, 87-95 parts coarse and fine aggregates 1-5 parts of filler External admixture 0.2-2 parts, The high-solids-content emulsified asphalt, by weight percentage, is made from the following raw materials: Petroleum asphalt 80wt%-93wt%, Polycyclic aromatic hydrocarbon amides 0.5wt%-3wt%, Citric acid fatty acid glycerides 1.0wt%-2wt%, Acrylic (ester) / behenol polyether-25 methacrylate copolymer 0.2wt%-1wt%, Remaining hydrochloric acid solution. The polycyclic aromatic hydrocarbon amide is composed of polycyclic aromatic hydrocarbon-12 amide and polycyclic aromatic hydrocarbon-16 amide.

2. The emulsified asphalt mixture according to claim 1, characterized in that: The mass ratio of polycyclic aromatic hydrocarbon-12 amide to polycyclic aromatic hydrocarbon-16 amide is (0.25-1.5):(0.25-1.5).

3. The emulsified asphalt mixture according to claim 1 or 2, characterized in that: The polycyclic aromatic hydrocarbon-12 amide is generated by an amidation reaction of polycyclic aromatic hydrocarbon carboxylic acid and dodecylamine, and the polycyclic aromatic hydrocarbon carboxylic acid is obtained by oxidizing asphalt with a strong acid. The polycyclic aromatic hydrocarbon-16 amide is generated by an amidation reaction of polycyclic aromatic hydrocarbon carboxylic acid and hexadecylamine, and the polycyclic aromatic hydrocarbon carboxylic acid is obtained by oxidizing asphalt with a strong acid.

4. The emulsified asphalt mixture according to claim 3, characterized in that: The preparation methods of polycyclic aromatic hydrocarbon-12 amides or polycyclic aromatic hydrocarbon-16 amides include: (1) The asphalt was chemically oxidized with a strong acid, and after separation and purification, polycyclic aromatic carboxylic acid was obtained; (2) After adding polycyclic aromatic hydrocarbon carboxylic acid, dodecylamine or hexadecylamine, catalyst and solvent to the reactor, seal the reactor and replace the gas inside the reactor with N2; (3) When the temperature inside the reactor reaches 160-180℃, turn on the stirring device and continue heating to 210-230℃. Maintain this temperature and pressure for 1-2 hours, then release the steam for 2-3 hours, and continue the reaction under vacuum for 3-5 hours. After the reaction is completed, lower the temperature to room temperature to obtain the crude product. (4) The crude product was washed and filtered with acetone and then dried under vacuum to obtain polycyclic aromatic hydrocarbon-12 amide or polycyclic aromatic hydrocarbon-16 amide final product.

5. The emulsified asphalt mixture according to claim 1 or 2, characterized in that: The pH value of the hydrochloric acid solution is 1-4.

6. The emulsified asphalt mixture according to claim 5, characterized in that: The preparation method of high solids content emulsified asphalt includes the following steps: A1. Add polycyclic aromatic hydrocarbon-12 amide, citric acid fatty acid glyceride, and acrylate (ester) / behenol polyether-25 methacrylate copolymer to a hot hydrochloric acid solution, stir evenly, and cool to obtain soap solution for later use. A2. Add polycyclic aromatic hydrocarbon-16 amide to hot asphalt, stir evenly to obtain activated asphalt mixture, and set aside; A3. Quickly add the soap solution obtained in step A1 to the activated asphalt mixture obtained in step A2, and continue stirring for a certain period of time to obtain high solids content emulsified asphalt.

7. The emulsified asphalt mixture according to claim 6, characterized in that: In step A1: the temperature of the hot hydrochloric acid solution is 70-80℃, and the temperature of the soap solution is 50-60℃; In step A2: the temperature of the hot asphalt is 110-130℃, and it is stirred at a rate of 1000r-2000r / min for 5-10min to obtain an activated asphalt mixture; In step A3: the soap solution and activated asphalt mixture are stirred for 10-20 minutes at 110-130℃ and 800-1500r / min to obtain high solids content emulsified asphalt.

8. The emulsified asphalt mixture according to claim 1 or 2, characterized in that: The curing modifier is a moisture-curing, single-component polyurethane.

9. The emulsified asphalt mixture according to claim 1 or 2, characterized in that: The admixtures are quicklime, anhydrous sodium sulfate, and / or cement.

10. A method for preparing the emulsified asphalt mixture according to any one of claims 1-9, characterized in that, Under stirring conditions, coarse and fine aggregates, curing modifiers, high-solids-content emulsified asphalt, fillers, and admixtures are added to the mixing pot in sequence and stirred until uniform. The temperature of the coarse and fine aggregates is 100-120℃, the temperature of the high-solids-content emulsified asphalt is 60℃-80℃, and the stirring speed is 1000-2000 r / min.

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