A high-performance mineral powder modified asphalt and its preparation method

Abstract

This invention relates to the field of modified asphalt technology, specifically to a high-performance mineral powder modified asphalt and its preparation method, comprising the following raw materials in parts by weight: 120-150 parts modifier, 5-12 parts mineral powder, and 100-150 parts asphalt. The modifier consists of two components, A and B, with a mass ratio of modifier A to modifier B of 10:(2-6). The modifier is used to non-polarize the surface of the mineral powder, improving the compatibility between the modified mineral powder and asphalt. This high-performance mineral powder modified asphalt and its preparation method modify the polar surface of the mineral powder to a non-polar surface, giving it hydrophobic and oleophilic properties. The modified, hydrophobic mineral powder floats on the water surface due to surface tension at the water interface, resulting in clear water; unmodified mineral powder sinks or suspends in the water, causing turbidity. This improves the compatibility between mineral powder and asphalt and significantly enhances the rutting resistance of the asphalt binder.

Description

Technical Field

[0001] This invention relates to the field of modified asphalt technology, specifically to a high-performance mineral powder modified asphalt and its preparation method. Background Technology

[0002] Mineral powder modified asphalt is a common asphalt modification method that can effectively increase the modulus of asphalt binder and improve the softening point and modulus value. However, since mineral powder is an inorganic substance, it usually has surface hydroxyl groups that exhibit polar hydrophilic properties. Its compatibility with the non-polar organic asphalt matrix relies solely on its limited oleophilic ability, thus its modulus-enhancing effect on asphalt is very limited. To further improve the dispersibility of mineral powder in asphalt and increase the compatibility between the two, this invention improves the oleophilic ability of mineral powder by modifying its surface to be hydrophobic, thereby increasing its compatibility with asphalt and improving the rutting resistance of the modified asphalt.

[0003] CN110317463A discloses a multi-particle-size red mud modified asphalt and its preparation method. The modified asphalt includes asphalt and red mud. The red mud is mixed in a ratio of large particle size: medium particle size: small particle size = (3-4):2:2. The preparation method involves uniformly mixing three types of red mud with different particle sizes calcined at high temperature according to the above mass ratio, then adding asphalt and stirring uniformly to obtain multi-particle-size red mud modified asphalt. While this technical solution discloses the influence of red mud particle size distribution on the performance of the modified asphalt, it does not disclose the chemical bonding relationship between the red mud particles and the asphalt matrix interface.

[0004] CN112723792A discloses a modified asphalt mixture and its preparation method. The mixture is made from raw materials comprising the following parts by weight: 4-7 parts modified asphalt, 90-98 parts aggregate, 8-10 parts mineral powder, and 0.1-0.9 parts fiber stabilizer. The preparation method is as follows: S1, after uniformly mixing the aggregate and mineral powder according to a set ratio, the mixture is heated to 190-220℃ for later use, obtaining the mixture; S2, the modified asphalt preheated to 170-175℃ is added to the heated mixture from S1, and after stirring at 180℃ for 40 seconds, the fiber stabilizer is added, and the mixture is stirred at 180℃ for 23-25 ​​seconds, obtaining the modified asphalt mixture. Although this technical solution discloses the composition of the modified asphalt mixture, it does not modify the mineral powder component to increase its compatibility with the base asphalt.

[0005] Although mineral powder significantly enhances the modulus of base asphalt, such as increasing softening point and modulus, it is an inert inorganic substance incompatible with base asphalt. Its limited oleophilic ability allows it to mix with the base asphalt, thus limiting its modulus-enhancing effect. Therefore, existing technologies lack effective methods to fully utilize the role of mineral powder in asphalt matrices. This paper proposes a high-performance mineral powder-modified asphalt and its preparation method to address these issues. Summary of the Invention

[0006] (a) Technical problems to be solved

[0007] To address the shortcomings of existing technologies, this invention provides a high-performance mineral powder modified asphalt, which has advantages such as improved performance of mineral powder modified asphalt and solves the problem of insufficient compatibility between mineral powder and asphalt.

[0008] (II) Technical Solution

[0009] To achieve the above-mentioned objective of improving the performance of mineral powder modified asphalt, the present invention provides the following technical solution: a high-performance mineral powder modified asphalt, comprising the following raw materials in parts by weight: 120-150 parts modifier, 5-12 parts mineral powder, and 100-150 parts asphalt. The modifier consists of two components, A and B, with a mass ratio of modifier A to modifier B of 10:(2-6). The modifier is used to perform non-polar modification on the surface of the mineral powder, thereby improving the compatibility between the modified mineral powder and the asphalt.

[0010] Preferably, the modifier is a stearic acid ethanol solution loaded with a catalyst for room temperature esterification reaction.

[0011] Preferably, the mineral powder is a carbonate or silicate mineral powder such as dolomite, omphacite, or kaolin.

[0012] Preferably, the asphalt is 70# petroleum asphalt or 90# petroleum asphalt.

[0013] Preferably, the mass ratio of petroleum asphalt to mineral powder is 100:(5-10).

[0014] Another technical problem to be solved by the present invention is to provide a method for preparing high-performance mineral powder modified asphalt, characterized by comprising the following steps:

[0015] (1) Put mineral powder into a conical flask, add modifier A and modifier B, and then stir magnetically;

[0016] (2) The modified mineral powder is obtained by washing and filtration and then stored in an oven for later use.

[0017] (3) Heat the asphalt to a fluid state, then add dried mineral powder to it. The mineral powder should be 5% to 10% of the asphalt mass. Stir thoroughly.

[0018] Preferably, modifier A is Al. 3+ An aqueous solution with an ion concentration of 1-3 g / L, and modifier B is an ethanol solution with a stearic acid concentration of 20-50 g / L. The magnetic stirring time in step (1) is 12-24 hours.

[0019] Preferably, the drying time in step (2) is 20 to 24 hours.

[0020] Preferably, the heating temperature in step (3) is 135–160°C, and the heating time is 20–30 minutes.

[0021] (III) Beneficial Effects

[0022] Compared with the prior art, the present invention provides a high-performance mineral powder modified asphalt and its preparation method, which has the following beneficial effects:

[0023] 1. This high-performance mineral powder modified asphalt and its preparation method modify the polar surface of mineral powder into a non-polar surface using a modifier, giving it hydrophobic and oleophilic properties. The modified, hydrophobic mineral powder floats on the water surface due to surface tension at the water interface, resulting in clear water; unmodified mineral powder sinks or suspends in the water, causing turbidity. This improves the compatibility between mineral powder and asphalt.

[0024] 2. This high-performance mineral powder modified asphalt and its preparation method utilize waste mine tailings (such as waste dolomite dust, omphacite tailings, etc.) as polymer raw materials, which is energy-saving, environmentally friendly, and low-cost.

[0025] 3. The high-performance mineral powder modified asphalt and its preparation method significantly improve the rutting resistance of asphalt binders compared with ordinary mineral powder modified asphalt. Attached Figure Description

[0026] Figure 1 These are diagrams showing the state of the mineral powder in water before and after surface modification according to the present invention.

[0027] Figure 2 These are state diagrams of the mineral powder in asphalt before and after surface modification according to the present invention;

[0028] Figure 3 This is a graph showing the test results of the present invention. Detailed Implementation

[0029] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] The following provides a specific implementation method for preparing high-performance mineral powder modified asphalt, including the following steps:

[0031] (1) Put mineral powder into a conical flask, add modifier A and modifier B, and then stir magnetically.

[0032] In this invention, the weight percentage of the mineral powder can be 5-10 parts, or 5-8 parts, or 8-10 parts. The mineral powder is a carbonate or silicate mineral powder such as dolomite, omphacite, or kaolin, and the particle size of the mineral powder does not exceed 0.075 mm. The weight percentage of modifier A can be 0-100 parts, or 0 parts, or 100 parts. The weight percentage of modifier B can be 10-50 parts, or 10-30 parts, or 30-50 parts.

[0033] (2) The modified mineral powder is obtained by washing and filtration and then stored in an oven for later use.

[0034] (3) Heat the asphalt to a fluid state, then add dried mineral powder and stir thoroughly.

[0035] In this invention, the weight of asphalt can be 100-200 parts, or even 100 parts or 200 parts, and the asphalt is 70# petroleum asphalt or 90# petroleum asphalt.

[0036] Examples and comparative examples for preparing high-performance mineral powder modified bitumen will be provided below.

[0037] Example 1:

[0038] In this embodiment, the components of the high-performance mineral powder modified asphalt are as follows by weight: 5 parts mineral powder, 100 parts modifier A, 30 parts modifier B, and 100 parts asphalt.

[0039] The preparation method of high-performance mineral powder modified asphalt in this embodiment includes the following steps:

[0040] (1) Put mineral powder into a conical flask, add modifier A and modifier B, and then stir magnetically.

[0041] (2) The modified mineral powder is obtained by washing and filtration and then stored in an oven for later use.

[0042] (3) Heat the asphalt to a fluid state, then add dried mineral powder and stir thoroughly.

[0043] Example 2:

[0044] In this embodiment, the components of the high-performance mineral powder modified asphalt are as follows by weight: 5 parts mineral powder, 100 parts modifier A, 20 parts modifier B, and 100 parts asphalt. The preparation method of the high-performance mineral powder modified asphalt in this embodiment is the same as in Embodiment 1.

[0045] Example 3:

[0046] In this embodiment, the components of the high-performance mineral powder modified asphalt are as follows by weight: 8 parts mineral powder, 100 parts modifier A, 40 parts modifier B, and 100 parts asphalt. The preparation method of the high-performance mineral powder modified asphalt in this embodiment is the same as in Embodiment 1.

[0047] Example 4:

[0048] In this embodiment, the components of the high-performance mineral powder modified asphalt are as follows by weight: 8 parts mineral powder, 100 parts modifier A, 50 parts modifier B, and 100 parts asphalt. The preparation method of the high-performance mineral powder modified asphalt in this embodiment is the same as in Embodiment 1.

[0049] Example 5:

[0050] In this embodiment, the components of the high-performance mineral powder modified asphalt are as follows by weight: 10 parts mineral powder, 100 parts modifier A, 20 parts modifier B, and 100 parts asphalt. The preparation method of the high-performance mineral powder modified asphalt in this embodiment is the same as in Embodiment 1.

[0051] Comparative Example 1:

[0052] This comparative example is based on Example 1 without the addition of modifier A and modifier B, and all other aspects remain unchanged.

[0053] Comparative Example 2:

[0054] This comparative example is based on Example 1, with the weight parts of modifier B adjusted to 10 parts and the weight parts of mineral powder adjusted to 8 parts, while all other parts remain unchanged.

[0055] Comparative Example 3:

[0056] This comparative example is based on Example 1, but the weight of asphalt is adjusted to 200 parts, while all other aspects remain unchanged.

[0057] It should be noted that the particle size of the mineral powder used in Examples 1-5 and Comparative Examples 1-3 is no greater than 0.075 mm.

[0058] The performance of the high-performance mineral powder modified asphalt prepared in Examples 1-5 and Comparative Examples 1-3 was tested. The phase angle δ and complex modulus of asphalt mastics with different fillers were tested according to the T315-04 test method. The rutting resistance factor of the asphalt mortar was measured and calculated. To evaluate the rutting resistance of asphalt mortar materials.

[0059] The test results are shown in Table 1:

[0060]

[0061] Analysis of the data in Table 1 shows that the surface-modified mineral powder-modified asphalt exhibits significantly higher rutting resistance than the unmodified mineral powder-modified asphalt. Within the optimal range, its rutting resistance is consistently excellent. However, when the content of modifier B is too low or the mineral powder content is too low, the improvement in rutting resistance of the modified asphalt is not significant. The results indicate that a suitable modifier ratio and an appropriate amount of mineral powder addition contribute to improving the rutting resistance of asphalt.

[0062] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A high performance mineral powder modified asphalt, characterized by, The modified agent is composed of two components A and B, the mass ratio of the modified agent A to the modified agent B is 10:2-6, the modified agent is used for non-polar modification of the surface of the mineral powder, and the compatibility of the modified mineral powder and the asphalt is improved. The modified agent is a stearic acid ethanol solution loaded with a normal temperature esterification reaction catalyst. The modifier A is Al 3+ An aqueous solution with an ion concentration of 1-3 g / L, and the modifier B is a stearic acid solution with a concentration of 20-50 g / L in ethanol. The mineral powder is a carbonate or silicate mineral powder.

2. The high performance mineral powder modified asphalt according to claim 1, characterized in that, The asphalt is 70# or 90# petroleum asphalt.

3. The high performance mineral powder modified asphalt according to claim 2, characterized in that, The mass ratio of the petroleum asphalt to the mineral powder is 100:5-10.

4. A method for producing high performance mineral powder modified bitumen based on any one of claims 1 to 3, characterized by, The method comprises the following steps: (1) putting the mineral powder into a conical flask, adding the modified agent A and the modified agent B into the conical flask, and then performing magnetic stirring; (2) performing washing and suction filtration to obtain the modified mineral powder, and then standby in an oven; (3) heating the asphalt into a flow state, then adding the dried mineral powder into the asphalt, the mass of the mineral powder is 5%-10% of the mass of the asphalt, and then performing sufficient stirring; The magnetic stirring time in the step (1) is 12-24 hours.

5. The method for preparing high performance mineral powder modified asphalt according to claim 4, characterized in that, The drying time in the step (2) is 20-24 hours.

6. The method of claim 4, wherein the high performance mineral powder modified asphalt is prepared by adding 0.1 to 0.3 parts by weight of the modified asphalt of the modified asphalt additive of claim 1 to 100 parts by weight of the base asphalt. The heating temperature in the step (3) is 135-160 DEG C, and the heating time is 20-30 minutes.

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