High-performance sepiolite modified emulsified asphalt and preparation method thereof

Abstract

The present application relates to the technical field of modified emulsified asphalt, and particularly relates to a high-performance sepiolite modified emulsified asphalt and a preparation method thereof.The emulsifier, stabilizer, sepiolite and water are mixed, the pH value is adjusted to 2-3, and a soap solution is obtained; the base asphalt, additive and the soap solution are sequentially mixed, and a high-performance sepiolite modified emulsified asphalt is obtained.The sepiolite has less impurities and a large specific surface area after acid treatment, the sepiolite fiber has a diameter of 200nm-1um, and the JY-R4 surfactant is used as the emulsifier, so that the problem of hydrophilicity but not oleophilicity of the sepiolite in the production process can be effectively solved, and the sepiolite can be uniformly dispersed in the asphalt and play a corresponding modification role.

Description

Technical Field

[0001] This invention relates to the field of modified emulsified asphalt technology, and in particular to a high-performance sepiolite-modified emulsified asphalt and its preparation method. Background Technology

[0002] Emulsified asphalt is prepared by mixing emulsifiers and asphalt. It possesses excellent performance characteristics, such as enabling cold application, extending the construction season, enhancing the adhesion between asphalt and aggregates, and improving the uniformity of the mixture. Emulsified asphalt also offers advantages such as saving asphalt and reducing environmental pollution. Modern road engineering places higher demands on the high-temperature performance, low-temperature performance, aging resistance, fatigue resistance, and storage stability of emulsified asphalt. Therefore, modified emulsified asphalt has emerged. Modified emulsified asphalt is mainly prepared by modifying emulsified asphalt or emulsifying modified asphalt.

[0003] Sepiolite (SEP) is a hydrous magnesium silicate clay mineral with a layered or chain-like structure. Its theoretical chemical formula is Si. 12 O 30 Mg8(OH)4(OH2)4·8H2O. Sepiolite crystals consist of two layers of silicon-oxygen tetrahedra and one layer of magnesium-containing central octahedrons, interconnected to form a 2:1 layered structure. Sepiolite is a natural mineral widely found in soils and sediments, typically gray, off-white, or cream-colored. Sepiolite not only possesses crystals that can reach heights of up to 900m... 2 With a specific surface area of ​​ / g, it also has the advantages of being non-toxic and odorless, having strong adsorption capacity, high temperature resistance, good insulation, high salt resistance, and good plasticity.

[0004] Sepiolite, a non-metallic mineral with a large specific surface area, strong adsorption capacity, and high temperature resistance, has a wide range of applications, but its use as a road material is limited. Similar silicate minerals such as palygorskite and montmorillonite are more widely researched and applied in road materials. However, sepiolite is hydrophilic but not oleophilic, making it prone to agglomeration. Therefore, how to provide a high-performance sepiolite-modified emulsified asphalt and its preparation method has become a pressing technical problem for those skilled in the art. Summary of the Invention

[0005] The purpose of this invention is to provide a high-performance sepiolite-modified emulsified asphalt and its preparation method to solve the above-mentioned technical problems.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0007] This invention provides a high-performance sepiolite-modified emulsified asphalt, prepared from raw materials comprising the following parts by mass:

[0008]

[0009] Furthermore, the emulsifier comprises one or more of JY-R4, JY-R10M, JY-C2, and JY-R1X; the stabilizer comprises one or more of anhydrous calcium chloride, polyvinyl alcohol, JY-CWD3 type emulsified asphalt stabilizer, ammonium chloride, and sodium carboxymethyl cellulose; and the additives comprise one or more of SBR additives, polyurethane, and ethylene-vinyl acetate copolymer.

[0010] Furthermore, the sepiolite is acid-treated sepiolite with a diameter of 200 nm to 1 μm.

[0011] This invention provides a method for preparing high-performance sepiolite-modified emulsified asphalt, comprising the following steps:

[0012] (1) Mix emulsifier, stabilizer, sepiolite and water to obtain a mixture, adjust the pH of the mixture to 2-3 to obtain soap solution;

[0013] (2) Mix the base asphalt and additives with soap solution in sequence to obtain high-performance sepiolite modified emulsified asphalt.

[0014] Furthermore, in step (1), the mixing temperature is 55–65°C.

[0015] Furthermore, in step (1), the mixing is performed under ultrasound for a duration of 0.5 to 1.5 hours.

[0016] Furthermore, in step (2), the mixing is carried out independently under shear, and the temperature of the base asphalt is 125-145°C; the mixing time is 3-10 min independently.

[0017] Furthermore, the shearing speed is 2500–3000 rpm.

[0018] The beneficial effects of this invention are:

[0019] The sepiolite-modified emulsified asphalt produced by this invention effectively solves the problem of sepiolite being hydrophilic but not oleophilic during the production process, allowing sepiolite to be uniformly dispersed in the asphalt and exert its corresponding modifying effect. This invention proposes a high-performance sepiolite-based modified emulsified asphalt suitable for industrial production and its preparation method. Detailed Implementation

[0020] This invention provides a high-performance sepiolite-modified emulsified asphalt, prepared from raw materials comprising the following parts by mass:

[0021]

[0022] In this invention, the content of the base asphalt is preferably 58 to 62 parts by weight, and more preferably 60 parts; the base asphalt in this invention is 70# base asphalt.

[0023] In this invention, the content of the emulsifier is preferably 1.5 to 2.5 parts by weight, more preferably 1.9 parts; the emulsifier is preferably one or more of JY-R4, JY-R10M and JY-C2, more preferably JY-R4.

[0024] In this invention, the content of the stabilizer is preferably 0.2 to 0.4 parts by weight, more preferably 0.25 parts; the stabilizer is preferably one or more of anhydrous calcium chloride, polyvinyl alcohol, JY-CWD3 type emulsified asphalt stabilizer and ammonium chloride, more preferably anhydrous calcium chloride.

[0025] In this invention, the content of sepiolite is preferably 0.2 to 0.4 parts by weight, and more preferably 0.23 parts by weight.

[0026] In this invention, the sepiolite is acid-treated sepiolite with a diameter of 200 nm to 1 μm, preferably 300 nm to 500 nm, and more preferably 400 nm.

[0027] In this invention, to modify the non-oleophilic properties of sepiolite and maximize the dispersion of sepiolite fibers in asphalt, a surfactant-modified sepiolite method is employed. Simultaneously, the surfactant can also act as an asphalt emulsifier, adsorbing onto the surface of asphalt particles, reducing the free energy of the asphalt, and forming a stable oil-in-water emulsion.

[0028] In this invention, the content of the additive is preferably 4 to 6 parts by weight, more preferably 5 parts; the additive is preferably SBR additive and / or polyurethane, more preferably SBR additive.

[0029] In this invention, the water content is preferably 29 to 34 parts by mass, and more preferably 32.62 parts by mass.

[0030] This invention provides a method for preparing high-performance sepiolite-modified emulsified asphalt, comprising the following steps:

[0031] (1) Mix emulsifier, stabilizer, sepiolite and water to obtain a mixture, adjust the pH of the mixture to 2-3 to obtain soap solution;

[0032] (2) Mix the base asphalt and additives with soap solution in sequence to obtain high-performance sepiolite modified emulsified asphalt.

[0033] In this invention, in step (1), the mixing temperature is 55-65°C, preferably 56-62°C, and more preferably 60°C.

[0034] In this invention, in step (1), the mixing is carried out under ultrasound for a duration of 0.5 to 1.5 hours, preferably 1 hour.

[0035] In this invention, in step (2), the mixing is carried out independently under shear, the temperature of the base asphalt is 125-145°C, preferably 135°C, and the mixing time is 3-10 min, preferably 5 min.

[0036] In this invention, the shearing speed is 2500-3000 rpm, preferably 2840 rpm.

[0037] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0038] The dosage of each raw material in Examples 1 to 5 is shown in Table 1 below.

[0039] Table 1 Raw Material Admixture

[0040]

[0041] Preparation method of high-performance sepiolite-modified emulsified asphalt:

[0042] 1) Add JY-R4 emulsifier, anhydrous calcium chloride stabilizer, and sepiolite to deionized water at 60℃ in sequence, stir until completely dissolved, and then subject the solution to ultrasonic vibration for 0.5 hours in a sealed state.

[0043] 2) Add hydrochloric acid to the above solution to adjust the pH value of the mixed solution. When the pH value is 2.5, the soap solution preparation is complete.

[0044] 3) First, shear the soap solution at 2840 rpm for 30 seconds using a colloid mill. Then, slowly and evenly pour in the weighed 70# base bitumen at 135℃ and shear for 3 minutes. Next, add SBR and continue shearing for 3 minutes.

[0045] Performance testing:

[0046] The high-performance sepiolite-modified emulsified asphalt obtained in Examples 1 to 5 was subjected to the following performance tests, and the test results are shown in Table 2 below:

[0047] Table 2 Performance Test Results

[0048]

[0049] The dosage of each raw material in Examples 6 to 10 is shown in Table 3 below.

[0050] Table 3 Raw Material Admixture

[0051]

[0052]

[0053] The preparation methods of Examples 6 to 10 are the same as those of Example 1.

[0054] The high-performance sepiolite-modified emulsified asphalt obtained in Examples 6 to 10 was subjected to the following performance tests, and the test results are shown in Table 4 below:

[0055] Table 4 Performance Tests

[0056]

[0057] Comparative Example 1

[0058] Ordinary emulsified asphalt

[0059] The formula for ordinary emulsified asphalt is as follows: 1.9 parts of JY-R4 emulsifier, 0.23 parts of sepiolite, 60 parts of 70# base asphalt, 0.25 parts of stabilizer, and 37.62 parts of deionized water.

[0060] The preparation method is the same as in Example 1.

[0061] As can be seen from the above embodiments, the present invention provides a high-performance sepiolite-modified emulsified asphalt and its preparation method. Table 4 shows that, compared to ordinary emulsified asphalt, the sepiolite-modified emulsified asphalt prepared according to the optimal material formulation exhibits a 17.6 (0.1 mm) decrease in penetration, a 15.9℃ increase in softening point (high-temperature resistance), and a 2.2-fold increase in ductility work at 5℃ (low-temperature crack resistance), indicating a significant improvement in the performance of the modified emulsified asphalt.

[0062] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A high-performance sepiolite-modified emulsified asphalt, characterized in that, From the following mass parts The material was prepared as follows: 55-65 parts of base asphalt; Emulsifier 1-3 parts; Stabilizer 0.1~0.5 parts; 0.1-0.5 parts of sepiolite; 3-8 parts of auxiliary agent; Water 28-35 parts; The emulsifier is JY-R4; The stabilizer comprises anhydrous calcium chloride, polyvinyl alcohol, JY-CWD3 type emulsified asphalt stabilizer, and chlorine. One or more of ammonium chloride and sodium carboxymethyl cellulose; The additive is SBR.

2. The high-performance sepiolite-modified emulsified asphalt according to claim 1, characterized in that, The sea Sepiolite is an acid-treated form of sepiolite, with a diameter ranging from 200 nm to 1 μm.

3. The method for preparing high-performance sepiolite-modified emulsified asphalt according to claim 1 or 2, Its characteristics are The process includes the following steps: (1) Mix emulsifier, stabilizer, sepiolite and water to obtain a mixture, adjust the pH of the mixture to 2~3 to obtain soap solution; (2) Mix the base asphalt and additives with soap solution in sequence to obtain high-performance sepiolite modified emulsified asphalt.

4. The preparation method according to claim 3, characterized in that, In step (1), the mixing temperature is 55~65℃.

5. The preparation method according to claim 3 or 4, characterized in that, In step (1), the mixture is mixed under ultrasound for 0.5 to 1.5 hours.

6. The preparation method according to claim 5, characterized in that, In step (2), the mixing is carried out independently under shear, and the temperature of the base asphalt is 125~145℃; the mixing time is 3~10min.

7. The preparation method according to claim 6, characterized in that, The shearing speed is 2500~3000 rpm.

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