Asphalt warm-mixing agent based on waste plastic cracking product and preparation method of asphalt warm-mixing agent

Abstract

The invention discloses an asphalt warm mixing agent based on a waste plastic cracking product and a preparation method thereof, and relates to the technical field of green asphalt warm mixing agents. The invention relates to an asphalt warm mixing agent based on waste plastic pyrolysis products. The asphalt warm mixing agent mainly comprises the following components in parts by mass: 40-70 parts of waste plastic pyrolysis oil, 15-35 parts of waste plastic pyrolysis residues, 0.5-5 parts of an emulsifier and 1-3 parts of a stabilizer. The waste plastic thermal cracking oil and the residues are used for replacing part of asphalt, so that the raw material cost is remarkably reduced. The stabilizing agent and the emulsifying agent in the warm mixing agent have a synergistic effect, so that the high-temperature stability and the low-temperature crack resistance of the asphalt are optimized, and the asphalt shows better pavement performance. The production temperature of the asphalt mixture is reduced, the energy consumption is reduced, and the greenhouse gas emission is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of green asphalt warm mix agents, and in particular to an asphalt warm mix agent based on waste plastic cracking products and a preparation method thereof. Background Art

[0002] With the rapid development of the global economy, the use of plastic products has increased dramatically, and the resulting problem of waste plastic disposal has become increasingly serious. Traditional methods of waste plastic disposal mainly include landfill and incineration, but these methods not only occupy a large amount of land resources but also cause serious environmental pollution. In recent years, waste plastic thermal cracking technology has gradually gained attention. By heating and cracking waste plastic in an oxygen-free or low-oxygen environment, it can be converted into high-value-added products such as fuel oil, gas, and solid residue, realizing the resource utilization of waste plastic.

[0003] The production and use of asphalt mixtures are crucial in road construction. However, traditional hot-mix asphalt production requires high temperatures, which not only consumes significant amounts of energy but also produces significant amounts of harmful gases and greenhouse gas emissions, negatively impacting the environment. To reduce energy consumption and environmental pollution, warm-mix asphalt technology has emerged. By adding a warm-mix agent to the asphalt mixture, warm-mix asphalt technology enables asphalt mixing and construction at lower temperatures, significantly reducing energy consumption and harmful gas emissions.

[0004] Currently, common warm-mix agents on the market mainly include organic additives, inorganic additives, and surfactants. However, most of these warm-mix agents suffer from high costs, environmental concerns, and poor compatibility with asphalt. Therefore, the development of efficient, environmentally friendly, and cost-effective warm-mix agents is of great practical significance. Asphalt warm-mix agents based on waste plastic pyrolysis products have emerged as a result. They not only effectively utilize the oil and residues produced by waste plastic pyrolysis, but also provide a new solution for warm-mix asphalt technology, effectively integrating waste plastic processing with road construction, with significant economic and social benefits. Summary of the Invention

[0005] The present invention aims to provide an efficient, environmentally friendly, low-cost asphalt warm mix agent based on waste plastic pyrolysis products and a preparation method thereof, so as to solve the problems of high cost, environmental unfriendliness and poor compatibility of existing warm mix agents, and at the same time realize the resource utilization of waste plastics.

[0006] To achieve the above-mentioned object, the technical solution adopted by the present invention is: an asphalt warm mix agent based on waste plastic pyrolysis products, mainly composed of the following components by weight: 40-70 parts of waste plastic pyrolysis oil, 15-35 parts of waste plastic pyrolysis residue, 0.5-5 parts of emulsifier, and 1-3 parts of stabilizer;

[0007] The stabilizer is a compound represented by Formula 1:

[0008]

[0009] The R1 is selected from any one of methyl, ethyl, propyl and cyanomethyl.

[0010] Furthermore, the waste plastic pyrolysis oil is a distilled fraction of a liquid product produced by pyrolysis of plastics at 350-500°C without oxygen;

[0011] The distillation is carried out at 150-400°C.

[0012] Furthermore, the plastic is selected from one or more of polyethylene plastic, polypropylene plastic, and polystyrene plastic.

[0013] Furthermore, the waste plastic pyrolysis residue is collected from a reactor, a distillation tower bottom or a condensation system during the production of waste plastic pyrolysis oil, and is in a semi-solid or solid state at room temperature.

[0014] Furthermore, the emulsifier is selected from: sodium lauryl sulfate.

[0015] Furthermore, the stabilizer is any one of the compounds shown in the following structures:

[0016]

[0017] A method for preparing an asphalt warm mix agent based on waste plastic pyrolysis products comprises the following steps:

[0018] a. Filter the waste plastic pyrolysis oil to remove mechanical impurities and heat it to 90-110°C to obtain preheated waste plastic pyrolysis oil; heat the waste plastic pyrolysis residue to 100-150°C to melt it into a flowable state to obtain a molten waste plastic pyrolysis residue;

[0019] b. adding the preheated waste plastic pyrolysis oil to the molten waste plastic pyrolysis residue at 90-110°C and stirring, stirring and mixing for 15-60 minutes until uniform, to obtain a mixture;

[0020] c. Add the emulsifier and stabilizer to the mixture, maintain the temperature at 60-90 ° C, and stir for 20-45 minutes to obtain a mixture B;

[0021] d. Cooling the mixture B to room temperature to obtain an asphalt warm mix agent based on the waste plastic pyrolysis product.

[0022] Furthermore, step c is carried out under a nitrogen atmosphere.

[0023] A method for producing warm-mix asphalt mixture using an asphalt warm-mix agent based on waste plastic cracking products. The asphalt warm-mix agent based on waste plastic cracking products is directly added to heated asphalt binder or aggregate before or during mixing, and the added amount is 2.0-8.0wt% of the asphalt binder mass.

[0024] Furthermore, the asphalt mixture containing the asphalt warm mix agent based on waste plastic pyrolysis products has a mixing temperature of 130-150°C, a paving temperature of 120-140°C, and a compaction temperature of 110-135°C.

[0025] An asphalt warm mix agent based on waste plastic cracking products can also be used in non-metallic additive materials.

[0026] The stabilizer described in the present invention has a polyhydroxy structure, a long alkyl chain structure, and a conjugated π-bond structure. The polyhydroxy structure is a highly polar group that can form hydrogen bonds with polar components in asphalt (such as colloids and asphaltenes). This interaction improves the compatibility of waste plastic cracking oil / residue with asphalt and prevents component separation. The polyhydroxy structure also imparts antioxidant properties to the stabilizer, ensuring the long-term stability of asphalt warm mix agents based on waste plastic cracking products. The polyhydroxy structure, through synergistic action with emulsifiers (such as sodium lauryl sulfate), reduces oil-water interfacial tension, promotes microemulsion formation, and facilitates uniform dispersion of the warm mix agent in asphalt, enabling low-temperature mixing. The long-chain alkyl group has a flexible carbon chain structure that can insert between asphalt molecular chains, acting as a "lubricant." The long-chain alkyl group ensures uniform dispersion of the stabilizer in asphalt warm mix agents based on waste plastic cracking products. The conjugated π-bond structure converts ultraviolet light into heat energy, protecting the asphalt warm mix agent based on waste plastic cracking products from ultraviolet corrosion. The stabilizer molecules have both hydrophilic ends (polyhydroxyl groups) and lipophilic ends (long-chain alkyl groups), forming an amphiphilic structure: the lipophilic end is anchored in the waste plastic pyrolysis oil / waste plastic pyrolysis residue, and the hydrophilic end is connected to the emulsifier interface, achieving "asphalt-pyrolysis product-emulsifier" three-phase stabilization.

[0027] Based on the synergistic effect among the waste plastic pyrolysis oil, waste plastic pyrolysis residue, emulsifier and stabilizer described in the present invention, the technical problems of high cost, environmental unfriendliness and poor compatibility of existing warm mix agents can be effectively solved. First of all, resource utilization is the key: waste plastic pyrolysis oil provides light fractions to reduce the viscosity of asphalt, and waste plastic pyrolysis residue simulates the colloid structure of asphalt as a semi-solid component. The two work together to achieve resource utilization of waste plastics and directly reduce the cost of raw materials by more than 40%. Secondly, interface stabilization and dispersion optimization are the core: the emulsifier reduces the oil-water interfacial tension through hydrophilic-lipophilic groups, and the stabilizer forms an "emulsifier-stabilizer composite interface" through its unique polyhydroxy structure, long alkyl chain and conjugated π bond, ensuring that the pyrolysis oil-residue blend is evenly dispersed in the asphalt to prevent component separation during storage or mixing. Ultimately, performance and environmental benefits are significantly improved: the pyrolysis oil and the long alkyl chains of the stabilizer synergistically reduce the mixing temperature to 130-150°C, while the rigid skeleton of the residue and the antioxidant properties of the stabilizer's polyhydroxy groups synergistically improve durability, not only reducing fuel consumption and CO2 emissions by 30-50%, but also extending the pavement's life and reducing lifecycle costs. This synergistic mechanism of "liquid-solid complementarity, interface strengthening, and functional integration" enables the warm mix agent to achieve a compaction temperature of 110-135°C and a greenhouse gas emission reduction of up to 20-30% at an addition level of only 2.0-8.0wt%, fully addressing cost, environmental protection, and compatibility goals.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] 1. Cost reduction trend: By using waste plastic pyrolysis oil and residue to replace part of the asphalt, the raw material cost is significantly reduced.

[0030] 2. Performance improvement trend: The stabilizer and emulsifier in the warm mix agent work synergistically to optimize the high-temperature stability and low-temperature crack resistance of asphalt, showing better road performance.

[0031] 3. Environmental benefit trend: Lowering the production temperature of asphalt mixture and reducing energy consumption can reduce greenhouse gas emissions. At the same time, the resource utilization of waste plastics reduces environmental pollution. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is the NMR image of the stabilizer 1 of the present invention. DETAILED DESCRIPTION

[0033] The following will clearly and completely describe the technical solution of the present invention in conjunction with the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0034] Preparation Example 1

[0035] Preparation of stabilizer 1:

[0036]

[0037] A1-Feeding: Under a nitrogen atmosphere, 10 g of raw material 1, 6.89 g of raw material 2, 8.06 g of anhydrous sodium carbonate and 120 g of a mixed solution of toluene, ethanol and water (volume ratio 2:1:1) were added to the reaction system in sequence, stirred evenly, replaced nitrogen twice, 1.32 g of tetrakis(triphenylphosphine)palladium was added to the reaction system, nitrogen was replaced again twice, and heated to 95°C and refluxed for 10 hours.

[0038] A1-Post-treatment: After the reaction, the product was filtered with silica gel cake, the organic phase was retained, and dried by spin-drying. The organic phase was subjected to silica gel column chromatography using a mixture of petroleum ether and ethyl acetate as eluent, and dried by spin-drying to obtain 8.54 g of intermediate 1.

[0039] The M / Z (M+H) of intermediate 1 + ): 290; actual molecular mass of intermediate 1: 289.

[0040] A2-Charge: Under a nitrogen atmosphere, add 8.54 g of intermediate 1, 7.94 g of raw material 3, 6.23 g of sodium carbonate, 0.1 g of target carbon, 0.38 g of triphenylphosphine and 110 g of toluene into the reaction system, stir evenly, heat to 110°C, and reflux for 12 h.

[0041] A2-Post-treatment: After the reaction is completed, the temperature is slightly lowered, and the product is filtered using a silica gel cake, dried by spin drying, and subjected to silica gel column chromatography using a mixture of petroleum ether and ethyl acetate as eluent, dried by spin drying, to obtain 10.52 g of stabilizer 1.

[0042] M / Z (M+H) of stabilizer 1 + ): 434; actual molecular mass of stabilizer 1: 433.

[0043] Stabilizer 1 1HNMR (Chloroform-d) δ8.46 (s, 1H), 7.31 (s, 2H), 7.08-6.98 (m, 2H), 6.75-6.65 (m, 2H), 5.92 (s, 2H), 4.43-4.33 (m, 2H), 4.21 (m, 1H), 3.81 (m, 1H), 3.69 (m, 1H), 3.46 (m, 1H), 3.34 (d, 1H), 3.28-3.10 (m, 2H), 3.07-2.86 (m, 5H), 2.76 (m, 1H), 1.75 (m, 1H), 1.63-1.33 (m, 2H), 1.33-1.19 (m, 5H), 0.97-0.82 (m, 3H). 1 HNMR) see Figure 1 .

[0044] Preparation Example 2-Preparation Example 4

[0045] In Preparation Examples 2-4, stabilizers 2-4 were prepared in sequence, referring to the preparation method of Preparation Example 1, replacing the raw material 2, and the rest remained the same as Preparation Example 1. The specific structure of raw material 2, stabilizer 2-stabilizer 4 structure, M / Z (M+H + )Data are shown in Table 1.

[0046] Table 1.

[0047]

[0048] Example 1

[0049] Preparation of asphalt warm mix agent based on waste plastic pyrolysis products:

[0050] 1. Raw material ratio:

[0051] Waste plastic pyrolysis oil: 60 parts;

[0052] Waste plastic pyrolysis residue: 25 parts;

[0053] Emulsifier: sodium lauryl sulfate, 2.5 parts;

[0054] Stabilizer: 2 parts of Stabilizer 1 (Stabilizer 1 prepared in Preparation Example 1).

[0055] The waste plastic pyrolysis oil is a liquid product produced by pyrolysis of polyethylene plastic at 450° C. in an oxygen-free environment, and is a fraction obtained by distillation (carried out at 200° C.).

[0056] The plastic pyrolysis residue is obtained from the semi-solid residue at room temperature collected at the bottom of a distillation tower during the production of waste plastic pyrolysis oil.

[0057] 2. Preparation method:

[0058] a. Filter 60 parts of waste plastic pyrolysis oil through a 10-mesh sieve to remove mechanical impurities, and then heat to 100°C to obtain preheated waste plastic pyrolysis oil; heat 25 parts of waste plastic pyrolysis residue to 120°C to melt it into a flowable state to obtain molten waste plastic pyrolysis residue;

[0059] b. At 100 ° C and stirring conditions (stirring rate 500 rpm), the preheated waste plastic pyrolysis oil was added to the molten waste plastic pyrolysis residue, and stirred at 300 rpm for 30 minutes until the mixture was uniform without stratification to obtain a mixture;

[0060] c. To the mixture were added 2.5 parts of sodium lauryl sulfate (emulsifier) ​​and 2 parts of stabilizer 1, maintaining the temperature at 75 ° C and stirring for 30 minutes under a nitrogen atmosphere to obtain a mixture B;

[0061] d. The mixture B is naturally cooled to room temperature to obtain an asphalt warm mix agent based on the waste plastic pyrolysis product.

[0062] The finished product of an asphalt warm mix agent based on waste plastic cracking products is a uniform black viscous liquid without precipitation or separation.

[0063] Example 2-Example 4

[0064] An asphalt warm mix agent based on waste plastic pyrolysis products was prepared by referring to the preparation method of Example 1, except that the stabilizers therein were replaced with stabilizer 2 to stabilizer 4 prepared in Preparation Examples 2 to 4, and the rest remained the same as Example 1.

[0065] Comparative Example 1

[0066] An asphalt warm mix agent based on waste plastic pyrolysis products was prepared by referring to the preparation method of Example 1, except that the stabilizer was replaced with antioxidant 1010, and the rest remained the same as Example 1.

[0067] The structure of antioxidant 1010 is: Antioxidant 1010 is a commonly used antioxidant stabilizer in warm mix asphalt.

[0068] Comparative Example 2

[0069] An asphalt warm mix agent based on waste plastic pyrolysis products was prepared by referring to the preparation method of Example 1, except that the stabilizer was replaced with comparative compound 2, and the rest remained the same as Example 1.

[0070] The structure of comparative compound 2 is: Compared with the stabilizer described in the present invention, it lacks a long-chain alkane structure.

[0071] Comparative Example 3

[0072] An asphalt warm mix agent based on waste plastic pyrolysis products was prepared by referring to the preparation method of Example 1, except that the stabilizer was not added, and the rest remained the same as Example 1.

[0073] Comparative Example 4

[0074] An asphalt warm mix agent based on waste plastic pyrolysis products was prepared by referring to the preparation method of Example 1, except that the mass fraction of waste plastic pyrolysis oil was replaced with 80 parts, and the rest remained the same as in Example 1.

[0075] Comparative Example 5

[0076] An asphalt warm mix agent based on waste plastic pyrolysis products was prepared by referring to the preparation method of Example 1, except that the mass fraction of the waste plastic pyrolysis residue was replaced with 5 parts, and the rest remained the same as in Example 1.

[0077] Performance testing:

[0078] The prepared warm mix agent (an asphalt warm mix agent based on waste plastic pyrolysis products prepared in the Examples and Comparative Examples) was added directly to the heated asphalt binder before mixing, at an amount of 5.0 wt% of the asphalt binder. Asphalt mixture production parameters included: mixing temperature: 140°C; paving temperature: 130°C; and compaction temperature: 120°C.

[0079] The high and low temperature performance tests of asphalt were carried out according to the Test Procedures for Asphalt and Asphalt Mixtures in Highway Engineering (JTGE20-2011). The data are shown in Table 2.

[0080] Table 2.

[0081]

[0082]

[0083] Among them, stability measures high-temperature stability, and the higher the value, the better. Bending tensile strain measures low-temperature crack resistance, and the higher the value, the better. The warm mix agent of the present invention shows significant advantages in both high-temperature stability and low-temperature crack resistance. Specifically, the embodiment group using the stabilizer of the present invention is better than the comparative group in both performance indicators, which reflects the key role of the stabilizer in improving the overall performance of asphalt. In contrast, the comparative group has a significant decline in performance due to the lack of the stabilizer of the present invention or the unreasonable ratio of ingredients, reflecting the synergistic effect of waste plastic pyrolysis oil and residue and the importance of the multifunctional structure of the stabilizer to the effect of the warm mix agent. This trend shows that the scheme of the present invention can not only effectively improve the road performance of asphalt, but also highlight its potential in optimizing the resource utilization of waste plastics.

[0084] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. An asphalt warm mix agent based on waste plastic cracking products, characterized in that: The method is mainly composed of the following components in parts by mass: 40-70 parts of waste plastic pyrolysis oil, 15-35 parts of waste plastic pyrolysis residue, 0.5-5 parts of emulsifier, and 1-3 parts of stabilizer; The stabilizer is a compound represented by Formula 1: The R1 is selected from any one of methyl, ethyl, propyl and cyanomethyl.

2. The asphalt warm mix agent based on waste plastic pyrolysis products according to claim 1, characterized in that: The waste plastic pyrolysis oil is a distilled fraction of a liquid product produced by pyrolysis of plastic at 350-500°C without oxygen; The distillation is carried out at 150-400°C.

3. The asphalt warm mix agent based on waste plastic pyrolysis products according to claim 2, characterized in that: The plastic is selected from one or more of polyethylene plastic, polypropylene plastic, and polystyrene plastic.

4. The asphalt warm mix agent based on waste plastic pyrolysis products according to claim 1, characterized in that: The waste plastic pyrolysis residue is collected from a reactor, a distillation tower bottom or a condensation system during the production of waste plastic pyrolysis oil, and is in a semi-solid or solid state at room temperature.

5. The asphalt warm mix agent based on waste plastic pyrolysis products according to claim 1, characterized in that: The emulsifier is selected from sodium lauryl sulfate.

6. The asphalt warm mix agent based on waste plastic pyrolysis products according to claim 1, characterized in that: The stabilizer is any one of the compounds shown in the following structures:

7. A method for preparing an asphalt warm mix agent based on waste plastic pyrolysis products according to any one of claims 1 to 6, characterized in that: The following steps are involved: a. Filter the waste plastic pyrolysis oil to remove mechanical impurities and heat it to 90-110°C to obtain preheated waste plastic pyrolysis oil; heat the waste plastic pyrolysis residue to 100-150°C to melt it into a flowable state to obtain a molten waste plastic pyrolysis residue; b. adding the preheated waste plastic pyrolysis oil to the molten waste plastic pyrolysis residue at 90-110°C and stirring, stirring and mixing for 15-60 minutes until uniform, to obtain a mixture; c. Add the emulsifier and stabilizer to the mixture, maintain the temperature at 60-90 ° C, and stir for 20-45 minutes to obtain a mixture B; d. Cooling the mixture B to room temperature to obtain an asphalt warm mix agent based on the waste plastic pyrolysis product.

8. The method for preparing an asphalt warm mix agent based on waste plastic pyrolysis products according to claim 7, characterized in that: The step c is carried out under a nitrogen atmosphere.

9. A method for producing warm mix asphalt mixture using an asphalt warm mix agent based on waste plastic pyrolysis products according to any one of claims 1 to 6, characterized in that: The asphalt warm mix agent based on waste plastic cracking products is directly added to the heated asphalt binder or aggregate before or during mixing, and the added amount is 2.0-8.0 wt% of the asphalt binder mass.

10. The method for producing warm mix asphalt mixture based on asphalt warm mix agent of waste plastic pyrolysis products according to claim 9, characterized in that: The asphalt mixture containing the asphalt warm mix agent based on waste plastic pyrolysis products has a mixing temperature of 130-150° C., a paving temperature of 120-140° C., and a compacting temperature of 110-135° C.

Images