Odor removing agent for road rubber modified asphalt as well as preparation method and application of odor removing agent

Abstract

The invention discloses an odor removing agent for road rubber modified asphalt as well as a preparation method and application thereof, and relates to the technical field of asphalt odor removing agent preparation, and the odor removing agent comprises the following components in percentage by mass: 20%-50% of aluminum hydroxide, 20%-50% of magnesium hydroxide, 15%-30% of silica fume, 5%-15% of plant fruit powder and 0.5%-1% of citric acid powder. According to the method, the effect of purifying the odor of the rubber modified asphalt is achieved from the two aspects of chemical neutralization reaction and physical adsorption, and the targeted chemical reaction is adopted, so that the problems of irritant odor of the rubber asphalt and excessive emission of asphalt smoke are solved from the source, and the functions of purifying the odor, suppressing smoke, reducing emission and reducing carbon are realized.

Description

[0001] This application claims priority to Chinese Patent Application No. 202511020280.7, filed on July 23, 2025, entitled "A neutralizing agent for road rubber modified asphalt and its preparation method and application", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This invention relates to the field of asphalt neutralizing agent preparation technology, and in particular to a neutralizing agent for road rubber-modified asphalt, its preparation method and application. Background Technology

[0003] Asphalt, as an important road construction material, is widely used in municipal roads, highways, and other projects. Due to its drawbacks—flowability at high temperatures and brittleness at low temperatures—asphalt cannot be directly used in the construction of surface and intermediate layers of asphalt roads. Instead, it requires thermal modification to improve its physical properties, such as softening point, penetration, adhesion, elongation, and aging resistance. This thermal modification process generates a large amount of harmful volatile organic compounds (VOCs). While these VOCs generated during processing at the factory can be collected and treated, this is only a temporary solution, and the environmental impact remains significant. Furthermore, the open nature of construction sites makes it difficult to effectively collect and treat fumes during the preparation and paving of modified asphalt mixtures, resulting in the generation of large amounts of harmful substances that directly harm construction workers and have a severely detrimental impact on the environment.

[0004] Besides using SBS modifiers alone, many asphalt processing companies also use waste rubber powder to modify asphalt. In addition to adding a small amount of SBS modifier, they add a certain amount of rubber powder (generally 15%~25%, and sometimes as high as 40%) to produce odorless rubber-modified asphalt. The reasons are as follows: first, it reduces costs, as waste rubber tire powder costs less than half the price of asphalt; second, rubber-modified asphalt can significantly improve the rutting resistance and service life of asphalt roads; and third, it can reduce noise and improve driving comfort. However, rubber tire powder contains high levels of 18 polycyclic aromatic hydrocarbons, including naphthalene, anthracene, and benzo[a]pyrene, generally 200~400 mg / kg, and some domestic tires even contain as much as 600~800 mg / kg. The content of sulfides and free sulfur is even higher, reaching 1.5%~3%. Sulfur in rubber powder can decompose at high temperatures to generate sulfur free radicals. These free radicals react chemically with asphalt at high temperatures, stripping hydrogen atoms from the polymer chains in the asphalt and combining to form hydrogen sulfide (H2S), which is then released as a gas. Hydrogen sulfide has an unpleasant odor and a pungent smell, seriously harming the health of workers and the living environment of surrounding residents.

[0005] However, although asphalt contains some toxic and harmful substances, it is indispensable for road construction; although recycled waste rubber tire powder also contains some toxic and harmful substances, it will cause greater pollution to the environment if it is not recycled.

[0006] To turn these resources from waste into treasure, rubber powder and asphalt must undergo harmless deodorization treatment. Therefore, deodorization technology and its effectiveness become extremely important and crucial.

[0007] The pungent odor released by asphalt and rubber under high temperatures is difficult to control effectively. Traditional deodorizers can only temporarily mask the odor and cannot eliminate odor molecules at the source, and there is also the problem of odor rebound. Moreover, most traditional deodorizers rely on physical adsorption or plant extracts to cover up the odor, which has low efficiency in removing harmful gases and poor deodorizing effect. Summary of the Invention

[0008] This invention provides a deodorizing agent for road rubber-modified asphalt, its preparation method, and its application, overcoming the shortcomings of existing deodorizing agents in terms of low removal rate of harmful gases in asphalt and poor deodorizing effect.

[0009] The first aspect of the present invention provides a deodorizing agent for road rubber-modified asphalt, comprising, by weight percentage: 20%-50% aluminum hydroxide, 20%-50% magnesium hydroxide, 15%-30% silica fume, 5%-15% plant fruit powder and 0.5%-1% citric acid powder.

[0010] Compared with existing technologies, this invention uses alkaline substances aluminum hydroxide and magnesium hydroxide as the main components of the deodorizing agent. This is because magnesium hydroxide and aluminum hydroxide can neutralize sulfides such as hydrogen sulfide and sulfur dioxide in rubber asphalt, generating magnesium hydrosulfide, aluminum hydrosulfide, magnesium sulfite, and aluminum sulfite, respectively. These substances remain in the modified asphalt, constituting the effective components of the modified asphalt, thereby removing harmful gases and preventing their volatilization. Simultaneously, the water (water vapor) generated during the reaction dilutes the concentration of harmful gases, further reducing the irritating odor. Citric acid powder accelerates the neutralization reaction between magnesium hydroxide and aluminum hydroxide and the sulfides in rubber asphalt, acting as a catalyst. This is because the acidic substances in rubber asphalt are weakly acidic. Under weakly acidic conditions, these acidic substances cannot completely trigger the neutralization reaction when mixed with the alkaline magnesium hydroxide and aluminum hydroxide. The addition of citric acid powder can adjust the pH value of the rubber asphalt to 5-6, ensuring that the neutralization reaction occurs and generating relatively stable, non-volatile substances, further improving the deodorizing effect. Meanwhile, this invention uses silica fume and plant fruit powder as physical adsorbents because silica fume and plant fruit powder have large specific surface areas, which can adsorb and inhibit free substances such as reactive sulfur and reactive nitrogen in rubber asphalt, thereby preventing odor from escaping. Moreover, plant fruit powder itself contains the natural aroma of plant fruits, which can mask the odor in rubber asphalt to a certain extent. Therefore, the components of this invention work synergistically to achieve the effect of deodorizing rubber asphalt from both chemical neutralization reaction and physical adsorption perspectives. Furthermore, it employs targeted chemical reactions to solve the problems of odor and excessive emissions of rubber asphalt at the source, achieving the functions of deodorization, smoke suppression, emission reduction, and carbon reduction.

[0011] Furthermore, the particle size of the aluminum hydroxide, the magnesium hydroxide, and the microsilica powder is greater than or equal to 1250 mesh.

[0012] Compared with existing technologies, aluminum hydroxide, magnesium hydroxide, and microsilica powder with a particle size of 1250 mesh or greater all have a higher specific surface area, which can improve the neutralization reaction efficiency and physical adsorption efficiency, thereby improving the odor removal effect.

[0013] Furthermore, the particle size of the plant fruit powder is greater than or equal to 1250 mesh.

[0014] Compared with existing technologies, when the particle size of plant fruit powder is greater than or equal to 1250 mesh, it can increase the adsorption capacity for free substances in rubber asphalt, thereby achieving the effect of deodorizing rubber asphalt.

[0015] Furthermore, the plant-based fruit powder includes at least one of mango powder, peach powder, and apple powder; Furthermore, the preferred plant-based fruit powder is mango powder.

[0016] Compared with existing technologies, this invention selects mango powder, peach powder, and apple powder as physical adsorbents because they are rich in dietary fiber, and the natural porous network structure formed by dietary fiber can capture odor molecules through physical adsorption, thereby achieving the effect of odor removal; moreover, mango powder, peach powder, and apple powder contain polyphenolic flavor substances, which can mask the odor in rubber asphalt, further improving the odor removal effect.

[0017] A second aspect of this invention provides a method for preparing a neutralizing agent for road rubber-modified asphalt, applicable to the preparation of the neutralizing agent, comprising the following steps: Weigh each component according to the stated composition and proportions; The aluminum hydroxide, magnesium hydroxide, and silica powder are mixed at 5℃-35℃ to obtain mixed system 1; The plant fruit powder is added to the mixture 1 to obtain the mixture 2; The citric acid powder is added to the mixture system 2 to obtain the deodorizing agent for road rubber modified asphalt.

[0018] Compared with existing technologies, this invention, in the preparation of the odor neutralizer, first uses mechanical stirring to uniformly disperse aluminum hydroxide, magnesium hydroxide, and microsilica powder, ensuring the homogeneity of these three inorganic materials. This ensures the homogeneity of the subsequent organic plant fruit powder and inorganic materials. Furthermore, the addition of plant fruit powder allows the polysaccharides and polyphenols in the powder to fill the gaps between the components of the odor neutralizer, forming an organic-inorganic composite adsorbent and enhancing the ability to capture complex odors. Finally, the addition of citric acid powder avoids premature contact between the citric acid powder and inorganic powders, preventing the loss of citric acid powder activity. This ensures its uniform distribution in the final system, and the citric acid powder accelerates the targeted reaction between the magnesium hydroxide and aluminum hydroxide components in the odor neutralizer and the sulfides in the asphalt rubber, thus acting more effectively on odor molecules.

[0019] Furthermore, when mixing the aluminum hydroxide, the magnesium hydroxide, and the silica powder, the stirring speed is 20 rpm-40 rpm, and the stirring time is 30 min-0 min; and / or, When the plant fruit powder is added to the mixing system 1, the stirring speed is 15 rpm-25 rpm, and the stirring time is 30 min-60 min; and / or, When adding the citric acid powder to the mixture 2, the stirring speed is 10 rpm-20 rpm and the stirring time is 30 min-60 min.

[0020] Compared with the prior art, the present invention controls the stirring speed of the preparation of mixing system 1, mixing system 2 and after adding citric acid powder to 20rpm-40rpm, 15rpm-25rpm and 10rpm-20rpm respectively when preparing the deodorizing agent. This can make the components fully mixed, thereby improving the overall stability and uniformity of the deodorizing agent.

[0021] The third aspect of this invention provides the application of the aforementioned deodorizing agent for road rubber-modified asphalt in the preparation of road rubber-modified asphalt.

[0022] Compared with existing technologies, the present invention applies the odor neutralizer to the preparation of rubber-modified asphalt, which can solve the problems of irritating odor of rubber asphalt and excessive emission of asphalt fumes from the source, and improve the odor neutralization effect of rubber asphalt.

[0023] The fourth aspect of this invention provides a method for preparing road rubber-modified asphalt, and the preparation of the aforementioned neutralizing agent, the process comprising: The base asphalt is heated to 150℃-160℃ to obtain high-temperature base asphalt with good fluidity. When the temperature of the high-temperature matrix asphalt is further increased to 160℃-185℃, rubber powder is added, and the temperature is controlled at 185℃-220℃. The initial modification is carried out for ≥30 minutes to obtain rubber asphalt. The neutralizing agent is added to the rubber-modified asphalt, and the catalytic reaction is carried out for 60-90 minutes to obtain neutral-tasting rubber-modified asphalt.

[0024] Furthermore, the mass ratio of the base asphalt to the rubber powder is (75-80):(20-25); the amount of the neutralizing agent added is 1%-2% of the mass of the rubber asphalt.

[0025] Compared with existing technologies, this invention modifies the base asphalt by first heating it to 150℃-160℃, at which point the base asphalt melts and plasticizes, becoming a highly fluid base asphalt that facilitates subsequent mixing. Then, rubber powder is added when the temperature is raised to 160℃-185℃, where the rubber powder swells and desulfurizes at high temperatures. Subsequently, modification is carried out at 185℃-220℃ for ≥30 minutes to promote full cross-linking between the rubber and the base asphalt, forming a stable modified system. The reason for adding the neutralizing agent only after the rubber asphalt has formed is that the asphalt system already possesses a rubber elastic network at this point, allowing the neutralizing agent to be evenly dispersed and act on the interface between the asphalt colloid and the rubber, thus better removing the odor from the rubber asphalt and achieving a neutralizing effect. Attached Figure Description

[0026] Appendix Figure 1 This is a photograph of the deodorizing agent for road rubber-modified asphalt prepared in Example 1.

[0027] Appendix Figure 2 This is a photograph of the deodorizing agent for road rubber-modified asphalt prepared in Example 2.

[0028] Appendix Figure 3 This is a photograph of the deodorizing agent for road rubber-modified asphalt prepared in Example 3.

[0029] Appendix Figure 4 This is a photograph of the deodorizing agent for road rubber-modified asphalt prepared in Example 4.

[0030] Appendix Figure 5 Line graphs showing the NMHC and TVOC emissions of IRPC70# rubber asphalt 1#, IRPC70# odorless rubber asphalt 2#, and IRPC70# odorless rubber asphalt 3# within 15 minutes; Series 1 shows the volume change of NMHC emissions from IRPC70# rubber asphalt 1#, Series 2 shows the volume change of TVOC emissions from IRPC70# rubber asphalt 1#, Series 3 shows the volume change of NMHC emissions from IRPC70# odorless rubber asphalt 2#, Series 4 shows the volume change of TVOC emissions from IRPC70# odorless rubber asphalt 2#, Series 5 shows the volume change of NMHC emissions from IRPC70# odorless rubber asphalt 3#, and Series 6 shows the volume change of TVOC emissions from IRPC70# odorless rubber asphalt 3#.

[0031] Appendix Figure 6 Line graphs showing the NMHC and TVOC emissions from Jingbo Petrochemical's 70# rubber asphalt 1#, 70# odorless rubber asphalt 2#, and 70# odorless rubber asphalt 3# within 15 minutes; Series 1 shows the volume change of NMHC emissions from Jingbo Petrochemical's 70# rubber asphalt 1#, Series 2 shows the volume change of TVOC emissions from Jingbo Petrochemical's 70# rubber asphalt 1#, Series 3 shows the volume change of NMHC emissions from Jingbo Petrochemical's 70# odorless rubber asphalt 2#, Series 4 shows the volume change of TVOC emissions from Jingbo Petrochemical's 70# odorless rubber asphalt 2#, Series 5 shows the volume change of NMHC emissions from Jingbo Petrochemical's 70# odorless rubber asphalt 3#, and Series 6 shows the volume change of TVOC emissions from Jingbo Petrochemical's 70# odorless rubber asphalt 3#. Detailed Implementation

[0032] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to specific embodiments. It should be understood that the specific embodiments described herein are only for explaining the present invention and are not intended to limit the present invention.

[0033] The pungent odor released during the processing and production of rubber-modified asphalt, as well as during the mixing and paving of rubber-modified asphalt mixtures, is difficult to control effectively. Traditional odor neutralizers can only temporarily mask the odor and cannot eliminate odor molecules at the source, and there is also the problem of odor rebound. Moreover, most traditional odor neutralizers rely on physical adsorption or plant extracts to mask the odor, which has low efficiency in removing harmful gases and poor odor neutralization effect.

[0034] To overcome the above-mentioned defects, the first aspect of the present invention provides a deodorizing agent for road rubber modified asphalt, which, by mass percentage, comprises: 20%-50% aluminum hydroxide, 20%-50% magnesium hydroxide, 15%-30% silica fume, 5%-15% plant fruit powder and 0.5%-1% citric acid powder.

[0035] Compared with existing technologies, when the above technical solution is adopted, the aluminum hydroxide and magnesium hydroxide components in the odor neutralizer combine with rubber asphalt and undergo a neutralization reaction with sulfides such as hydrogen sulfide and sulfur dioxide in the rubber asphalt, generating magnesium hydrosulfide, aluminum hydrosulfide, magnesium sulfite, and aluminum sulfite. These substances remain in the modified asphalt, constituting the modified asphalt components, thereby removing harmful gases. At the same time, the water (water vapor) generated during the reaction dilutes the concentration of harmful gases, further reducing the irritating odor. Citric acid powder can accelerate the neutralization reaction between magnesium hydroxide and aluminum hydroxide and the sulfides in rubber asphalt, acting as a catalyst. This is because the acidic substances in rubber asphalt are weakly acidic. Under weakly acidic conditions, these acidic substances cannot completely trigger the neutralization reaction when mixed with the alkaline magnesium hydroxide and aluminum hydroxide. The addition of citric acid powder can adjust the pH value of the rubber asphalt to 5-6, ensuring that the neutralization reaction occurs and generating relatively stable, non-volatile substances, further improving the odor neutralization effect. Meanwhile, in practical applications, silica fume and plant fruit powder act as physical adsorbents, adsorbing and inhibiting free substances such as active sulfur and active nitrogen in rubber asphalt, thus preventing the escape of odors.

[0036] Furthermore, during the processing, mixing, and paving of rubber-modified asphalt, both the asphalt and the finished mixture are consistently kept at high temperatures, typically not lower than 150°C. Therefore, neither the asphalt nor the mixture contains aqueous solutions, eliminating the conditions for hydrolysis. Magnesium hydrosulfide, aluminum hydrosulfide, aluminum sulfite, and magnesium sulfite are unlikely to undergo hydrolysis in rubber-modified asphalt or its mixture. Conversely, due to the high viscosity of rubber-modified asphalt, these byproducts can be effectively coated by the asphalt, maintaining a relatively stable molecular state and becoming effective components of the rubber-modified asphalt.

[0037] In some embodiments, the plant-based fruit powder includes at least one of mango powder, peach powder, and apple powder.

[0038] For example, plant-based fruit powder can be mango powder.

[0039] For example, plant-based fruit powders can also be selected from mango powder and peach powder; and the mass ratio of the two is (8-10):(1~2).

[0040] For example, the plant-based fruit powder can also be selected from mango powder, peach powder and apple powder, and the mass ratio of the three is (8-10):(1-2):(0.5-1); further, the mass ratio of the three can be selected as 8:2:1, 9:1.5:1, 10:1:0.5 or any range of point values.

[0041] When using the above technical solution, the natural porous network structure formed by the abundant dietary fiber in mango powder, peach powder, and apple powder captures odor molecules through physical adsorption, achieving a deodorizing effect. Furthermore, the polyphenolic flavor compounds in mango powder, peach powder, and apple powder mask the odor in rubber asphalt, enhancing the deodorizing effect. The inventors' experiments have shown that selecting mango powder alone achieves the best deodorizing effect.

[0042] In some embodiments, the citric acid powder is anhydrous citric acid powder and / or citric acid monohydrate powder.

[0043] In some embodiments, the citric acid powder can be obtained commercially. For example, the citric acid powder can be purchased from Shandong Yingxuan Industrial Co., Ltd. as follows: 99.7% pure anhydrous citric acid under the "Yingxuan" brand; 99% pure citric acid under the "Yingxuan" brand; 99% pure citric acid under the "Yingxuan" brand; 99% pure citric acid under the "Yingxuan" brand; or 99% pure citric acid under the "Yingxuan" brand; or 99% pure citric acid powder ... powder under the "Yingxuan" brand; or citric acid powder powder under the "Yingxuan" brand; or

[0044] In some embodiments, when the citric acid powder is a mixture of anhydrous citric acid powder and monohydrate citric acid powder, the mass ratio of anhydrous citric acid powder to monohydrate citric acid powder is (7-8):(2-3). For example, the mass ratio of anhydrous citric acid powder to monohydrate citric acid powder can be 7:3, 7.5:2.5, or 8:2, or any range of two of the aforementioned ratios. Preferably, the mass ratio of anhydrous citric acid powder to monohydrate citric acid powder is 8:2.

[0045] Preferably, the citric acid powder is anhydrous citric acid powder. More preferably, the citric acid powder is anhydrous citric acid powder with a purity of ≥99.5%. Even more preferably, the citric acid powder is anhydrous citric acid powder with a purity of ≥99.7%.

[0046] When the above technical solution is adopted, the citric acid powder is anhydrous citric acid powder with a purity of ≥99.7%, which has the highest activity. This not only ensures that aluminum hydroxide, magnesium hydroxide and sulfides such as hydrogen sulfide and sulfur dioxide in rubber asphalt are neutralized, but also accelerates the neutralization reaction of magnesium hydroxide and aluminum hydroxide with sulfides in rubber asphalt, thereby achieving the best odor removal effect.

[0047] In some embodiments, the particle size of the citric acid powder is greater than or equal to 1250 mesh.

[0048] When the above technical solution is adopted, citric acid powder has a high specific surface area, which allows it to fully contact other components and further ensures the catalytic reaction.

[0049] Example 1, the deodorizing agent for road rubber modified asphalt, comprises, by mass percentage, 40% aluminum hydroxide, 20% magnesium hydroxide, 30% silica fume, 9% plant fruit powder (100% mango powder) and 1% anhydrous citric acid powder with a purity of 99.5%.

[0050] Example 2, the deodorizing agent for road rubber modified asphalt, by mass percentage, includes: 35% aluminum hydroxide, 29.5% magnesium hydroxide, 20% silica fume, 15% plant fruit powder (mango powder: peach powder: apple powder in a mass ratio of 10:2:1), and 0.5% a mixture of anhydrous citric acid powder with a purity of 99.5% and monohydrate citric acid powder with a purity of 99% (anhydrous citric acid powder to monohydrate citric acid powder in a mass ratio of 8:2).

[0051] Example 3, the deodorizing agent for road rubber modified asphalt, comprises, by mass percentage, 18% aluminum hydroxide, 50% magnesium hydroxide, 16% silica fume, 15% plant fruit powder (100% mango powder) and 1% anhydrous citric acid powder with a purity of 99.7%.

[0052] Example 4, the deodorizing agent for road rubber modified asphalt, by mass percentage, includes: 30% aluminum hydroxide, 40% magnesium hydroxide, 15% silica fume, 14% plant fruit powder (mango powder: peach powder in a mass ratio of 8:2), and 1% a mixture of anhydrous citric acid powder with a purity of 99.7% and monohydrate citric acid powder with a purity of 99% (anhydrous citric acid powder to monohydrate citric acid powder in a mass ratio of 7:3).

[0053] Example 5, the deodorizing agent for road rubber modified asphalt, comprises, by mass percentage, 25% aluminum hydroxide, 35% magnesium hydroxide, 30% silica fume, 9% plant fruit powder (100% mango powder) and 1% anhydrous citric acid powder with a purity of 99.5%.

[0054] In some embodiments, the particle size of aluminum hydroxide, magnesium hydroxide, and silica powder is greater than or equal to 1250 mesh.

[0055] When the above technical solution is adopted, aluminum hydroxide, magnesium hydroxide, and microsilica powder all have high specific surface areas, which improves the neutralization reaction efficiency and physical adsorption efficiency, and improves the odor removal effect.

[0056] In some embodiments, the particle size of the plant fruit powder is greater than or equal to 1250 mesh.

[0057] When the above technical solution is adopted, the plant fruit powder has a large specific surface area, which increases the adsorption capacity for free substances in rubber asphalt, thereby achieving the effect of deodorizing rubber asphalt.

[0058] A second aspect of this invention provides a method for preparing a neutralizing agent for road rubber-modified asphalt, applicable to the preparation of the aforementioned neutralizing agent, comprising the following steps: Weigh each component according to the stated composition and proportions; Aluminum hydroxide, magnesium hydroxide, and silica powder are mixed at 5℃-35℃ to obtain mixed system 1; for example, the temperature can be selected as a range of values ​​consisting of 5℃, 15℃, 25℃, 35℃ or any point value, preferably 25℃-30℃; Plant fruit powder is added to mixture system 1 to obtain mixture system 2; Citric acid powder is added to the mixture system 2 to obtain the deodorizing agent for road rubber modified asphalt.

[0059] Compared with existing technologies, when preparing the odor neutralizer using the above-mentioned technical solution, aluminum hydroxide, magnesium hydroxide, and microsilica powder constitute a uniformly dispersed inorganic material, which inhibits the volatilization of odor molecules in asphalt. Furthermore, the addition of plant fruit powder allows the polysaccharides and polyphenols in the powder to fill the gaps between the components of the odor neutralizer, forming an organic-inorganic composite adsorbent and enhancing the ability to capture complex odors. Finally, the addition of citric acid powder avoids premature contact between the citric acid powder and the inorganic powder, preventing the loss of citric acid powder's activity. This ensures its uniform distribution in the final system and accelerates the targeted reaction between the magnesium hydroxide and aluminum hydroxide components in the odor neutralizer and the sulfides in the asphalt rubber, thus acting more effectively on odor molecules.

[0060] In some embodiments, when mixing aluminum hydroxide, magnesium hydroxide, and silica powder, the stirring speed is 20 rpm to 40 rpm, and the stirring time is 30 min to 60 min. For example, the stirring speed can be specifically selected from a range of 20 rpm, 30 rpm, 40 rpm, or any value, preferably 30 rpm to 40 rpm; the stirring time can be specifically selected from a range of 30 min, 40 min, 60 min, or any value, preferably 40 min to 50 min.

[0061] In some embodiments, when the plant fruit powder is added to the mixing system 1, the stirring speed is 15 rpm-25 rpm and the stirring time is 30 min-60 min. For example, the stirring speed can be specifically selected as a range of values ​​consisting of 15 rpm, 20 rpm, 25 rpm, or any point value, preferably 20 rpm-25 rpm; the stirring time can be specifically selected as a range of values ​​consisting of 30 min, 40 min, 60 min, or any point value, preferably 40 min-50 min.

[0062] In some embodiments, when adding citric acid powder to the mixing system 2, the stirring speed is 10 rpm-20 rpm and the stirring time is 30 min-60 min; for example, the stirring speed can be specifically selected as a range of values ​​composed of 10 rpm, 15 rpm, 20 rpm, or any point value, preferably 15 rpm-20 rpm; the stirring time can be specifically selected as a range of values ​​composed of 30 min, 40 min, 60 min, or any point value, preferably 40 min-50 min.

[0063] When the above technical solution is adopted, the components are thoroughly mixed, which improves the stability and uniformity of the neutralizing agent.

[0064] The third aspect of this invention provides the application of a deodorizing agent for road rubber-modified asphalt in the preparation of road rubber-modified asphalt.

[0065] Compared with existing technologies, applying the neutralizing agent to the preparation of modified rubber asphalt solves the problems of irritating odor of rubber asphalt and excessive emissions of asphalt fumes from the source. It can reduce the emissions of non-methane total hydrocarbons (NMHC) by about 60% and VOCs by 60%-70%, thus improving the neutralizing effect on rubber-modified asphalt.

[0066] The fourth aspect of this invention provides a method for preparing road rubber-modified asphalt, using a neutralizing agent, the process comprising: The base asphalt is heated to 150℃-160℃ to obtain high-temperature base asphalt; for example, the temperature of the base asphalt after heating can be selected as a range of values ​​composed of 150℃, 155℃, 160℃ or any point value, preferably 155℃-160℃. When the temperature of the high-temperature matrix asphalt is further increased to 160℃-185℃, rubber powder is added, and the temperature is controlled at 185℃-220℃. The initial modification is carried out for ≥30 minutes to obtain rubber asphalt. For example, the temperature after the base asphalt is further heated can be selected as a range of values ​​consisting of 160℃, 170℃, 180℃, 185℃ or any point value, preferably 170℃-185℃; For example, the temperature during modification can be selected from 185℃, 190℃, 200℃, 220℃ or any range of values, preferably 200℃-220℃; the modification time can be selected from 60min, 90min, 120min or any range of values, preferably 90min-100min. The odor neutralizer is added to the rubber-modified asphalt, and the catalytic reaction is carried out for 60-90 minutes to obtain odor-neutralized rubber-modified asphalt. For example, the catalytic time can be selected as a range of values ​​consisting of 60 min, 70 min, 80 min, 90 min, or any point value, preferably 70 min-90 min.

[0067] According to the present invention, the rubber asphalt is also called rubber-modified asphalt; those skilled in the art will understand that rubber asphalt and rubber-modified asphalt refer to the same material.

[0068] In some embodiments, the mass ratio of base asphalt to rubber powder is (75-80):(20-25); the amount of neutralizing agent added is 1%-2% of the mass of rubber asphalt; for example, the mass ratio of base asphalt to rubber powder is 75:25, 80:20, 76:24 or any range of values; the amount of neutralizing agent added is 1%, 2%, 1.5% of the total amount of rubber asphalt or any range of values, preferably 1%-1.5%. It should be understood that in practical applications, the proportion of neutralizing agent added can be appropriately adjusted according to the amount of rubber powder added and the intensity of the odor on site.

[0069] Compared with existing technologies, the above technical solution modifies rubber asphalt by first heating the base asphalt to 150℃-160℃, at which point the base asphalt melts and plasticizes, becoming a base asphalt with good fluidity, which facilitates subsequent mixing; then, rubber powder is added when the temperature is raised to 160℃-185℃, at which point the rubber powder swells and desulfurizes at high temperature, and then modification is carried out at 185℃-220℃ for ≥30 minutes, which promotes full cross-linking between rubber and base asphalt, forming a stable modified system; after the rubber-modified asphalt is formed, an odor neutralizer is added, which allows the odor neutralizer to be evenly dispersed and act on the interface between the asphalt colloid and the rubber, better removing the odor in the rubber asphalt and achieving the effect of odor neutralization.

[0070] To better illustrate the technical solution of the present invention, the following specific embodiments are also provided. It should be understood that, unless otherwise specified, all raw materials used in the following embodiments are commercially available.

[0071] Example 1 A deodorizing agent for modified asphalt used in road rubber, comprising, by weight percentage: 40% aluminum hydroxide (1250 mesh), 20% magnesium hydroxide (1250 mesh), 30% silica fume (1250 mesh), 9% plant fruit powder (100% mango powder (1250 mesh)) and 1% anhydrous citric acid powder (1250 mesh) with a purity of 99.5%.

[0072] The preparation process of the above-mentioned deodorizing agent is as follows: Weigh each component according to the above composition and proportions; At 5℃, aluminum hydroxide, magnesium hydroxide and silica powder were mixed and stirred at 20 rpm for 60 min to obtain mixed system 1; Add the mango powder to mixture 1 and stir at 15 rpm for 30 minutes to obtain mixture 2. Add anhydrous citric acid powder to mixture 2 and stir at 10 rpm for 30 minutes to obtain a deodorizing agent for road rubber-modified asphalt. See the actual product image. Figure 1 .

[0073] The anhydrous citric acid powder mentioned above was purchased from Shandong Lemon Biochemical Co., Ltd., and was a 99.5% pure anhydrous citric acid powder under the "Tiantian" brand.

[0074] Example 2 A deodorizing agent for modified asphalt used in road rubber production, comprising, by weight percentage: 35% aluminum hydroxide (1250 mesh), 29.5% magnesium hydroxide (1250 mesh), 20% silica fume (1250 mesh), 15% plant fruit powder (mango powder (1250 mesh), peach powder (1250 mesh), apple powder (1250 mesh) in a weight ratio of 10:2:1), and a mixture of anhydrous citric acid powder (1250 mesh) with a purity of 99.5% and citric acid monohydrate powder (1250 mesh) with a purity of 99% (mass ratio of anhydrous citric acid powder to citric acid monohydrate powder is 8:2).

[0075] The preparation process of the above-mentioned deodorizing agent is as follows: At 15℃, aluminum hydroxide, magnesium hydroxide and silica powder were mixed and stirred at 30 rpm for 50 min to obtain mixed system 1; Add mango powder, peach powder, and apple powder to mixture system 1, and stir at 20 rpm for 40 minutes to obtain mixture system 2; Add a mixture of monohydrate citric acid powder and anhydrous citric acid powder to mixing system 2, and stir at 15 rpm for 40 minutes to obtain a deodorizing agent for road rubber-modified asphalt. See the actual product image. Figure 2 .

[0076] The monohydrate citric acid powder mentioned above was purchased from Sichuan Huanxu Biotechnology Co., Ltd., and had a purity of 99%. The anhydrous citric acid powder mentioned above was purchased from Shandong Lemon Biochemical Co., Ltd., and had a purity of 99.5%.

[0077] Example 3 A deodorizing agent for road rubber-modified asphalt, comprising, by weight percentage: 18% aluminum hydroxide (1250 mesh), 50% magnesium hydroxide (1250 mesh), 16% silica fume (1250 mesh), 15% mango powder (1250 mesh), and 1% anhydrous citric acid powder (1250 mesh) with a purity of 99.7%.

[0078] The preparation process of the above-mentioned deodorizing agent is as follows: At 25°C, aluminum hydroxide, magnesium hydroxide, and silica powder were mixed and stirred at 40 rpm for 40 min to obtain mixed system 1. Add the mango powder to mixture 1 and stir at 25 rpm for 60 minutes to obtain mixture 2. Anhydrous citric acid powder was added to mixture 2 and stirred at 20 rpm for 60 min to obtain a deodorizing agent for road rubber-modified asphalt. See the image for the actual product. Figure 3 .

[0079] The anhydrous citric acid powder mentioned above was purchased from Shandong Yingxuan Industrial Co., Ltd., and was labeled as "Yingxuan" brand anhydrous citric acid with a purity of 99.7%.

[0080] Example 4 A deodorizing agent for modified asphalt used in road rubber production, comprising, by weight percentage: 30% aluminum hydroxide (1250 mesh), 40% magnesium hydroxide (1250 mesh), 15% silica fume (1250 mesh), 14% plant fruit powder (mango powder (1250 mesh) to peach powder (1250 mesh) in a weight ratio of 8:2), and 1% a mixture of anhydrous citric acid powder (1250 mesh) with a purity of 99.7% and citric acid monohydrate powder (1250 mesh) with a purity of 99% (the weight ratio of anhydrous citric acid powder to citric acid monohydrate powder is 7:3).

[0081] The preparation process of the above-mentioned deodorizing agent is as follows: At 35°C, aluminum hydroxide, magnesium hydroxide, and silica powder were mixed and stirred at 40 rpm for 30 min to obtain mixture system 1. Add mango powder, peach powder, and apple powder to mixture system 1, and stir at 25 rpm for 50 minutes to obtain mixture system 2; Add a mixture of anhydrous citric acid powder and monohydrate citric acid powder to mixing system 2, and stir at 20 rpm for 50 min to obtain a deodorizing agent for road rubber-modified asphalt. See the actual product image. Figure 4 .

[0082] The anhydrous citric acid powder mentioned above was purchased from Shandong Yingxuan Industrial Co., Ltd., which produces "Yingxuan" brand anhydrous citric acid with a purity of 99.7%, and the monohydrate citric acid powder mentioned above was purchased from Shandong Lemon Biochemical Co., Ltd., which produces "Tiantian" brand monohydrate citric acid with a purity of 99%.

[0083] Example 5 A deodorizing agent for modified asphalt used in road rubber, comprising, by weight percentage: 25% aluminum hydroxide (1250 mesh), 35% magnesium hydroxide (1250 mesh), 30% silica fume (1250 mesh), 9% plant fruit powder (100% mango powder (1250 mesh)) and 1% anhydrous citric acid powder (1250 mesh) with a purity of 99.5%.

[0084] The preparation process of the above-mentioned deodorizing agent is as follows: Weigh each component according to the above composition and proportions; At 5℃, aluminum hydroxide, magnesium hydroxide and silica powder were mixed and stirred at 20 rpm for 60 min to obtain mixed system 1; Add the mango powder to mixture 1 and stir at 15 rpm for 30 minutes to obtain mixture 2. Add anhydrous citric acid powder to mixture system 2 and stir at 10 rpm for 30 min to obtain a deodorizing agent for road rubber modified asphalt.

[0085] The anhydrous citric acid powder mentioned above was purchased from Shandong Lemon Biochemical Co., Ltd., and was labeled as "Tiantian" brand anhydrous citric acid with a purity of 99.5%.

[0086] Comparative Example 1 Taking Example 3 as an example, compared with Example 3, anhydrous citric acid powder was removed, the total mass fraction of microsilica powder was increased to 17%, and the remaining components and preparation process remained unchanged, thus obtaining a neutralizing agent for rubber-modified asphalt.

[0087] Comparative Example 2 Taking Example 3 as an example, compared with Example 3, oxalic acid powder with a purity of 99.6% was used to replace anhydrous citric acid powder with a purity of 99.7% in an equal amount, while the other components and preparation process remained unchanged, and a neutralizing agent for rubber-modified asphalt was prepared.

[0088] Comparative Example 3 Taking Example 3 as an example, compared with Example 3, the silica powder was removed, the total mass fraction of plant fruit powder was increased to 31%, and the remaining components and preparation process remained unchanged, thus obtaining a neutralizing agent for rubber-modified asphalt.

[0089] Comparative Example 4 Taking Example 3 as an example, compared with Example 3, the plant fruit powder was removed, the total mass fraction of microsilica powder was increased to 31%, and the remaining components and preparation process remained unchanged, thus obtaining a neutralizing agent for rubber-modified asphalt.

[0090] Comparative Example 5 Taking Example 3 as an example, compared with Example 3, the plant fruit powder was replaced by an equal amount of natural plant extract, while the other components and preparation process remained unchanged; wherein, the natural plant extract included rosin, lemon peel extract and peppermint extract in a mass ratio of 5:1:1, and a neutralizing agent for rubber-modified asphalt was prepared.

[0091] Comparative Example 6 Taking Example 3 as an example, compared with Example 3, aluminum hydroxide was removed, the total mass fraction of magnesium hydroxide was increased to 68%, and the remaining components and preparation process remained unchanged, thus obtaining a neutralizing agent for rubber-modified asphalt.

[0092] Comparative Example 7 Taking Example 3 as an example, compared with Example 3, magnesium hydroxide was removed, the total mass fraction of aluminum hydroxide was increased to 68%, and the remaining components and preparation process remained unchanged, thus obtaining a neutralizing agent for rubber-modified asphalt.

[0093] Performance testing Test Example 1 Odorless rubber-modified asphalt 1# to odorless rubber-modified asphalt 5# were prepared using the odor-neutralizing agents for road rubber-modified asphalt in Examples 1 to 5, respectively. Modified asphalt was also prepared using the odor-neutralizing agents for road rubber-modified asphalt in Comparative Examples 1 to 7, respectively, and rubber-modified asphalt D1# to rubber-modified asphalt D7# were obtained.

[0094] The preparation process of the above-mentioned odorless rubber-modified asphalt No. 1 is as follows: The base asphalt is heated to 150°C to obtain high-temperature base asphalt; The temperature of the high-temperature base asphalt was further increased to 160℃, rubber powder was added, and then the temperature was controlled at 190℃ for 50 minutes of preliminary modification to obtain rubber-modified asphalt. Add a neutralizing agent to rubber asphalt and catalyze the reaction for 60 minutes to obtain neutralizing rubber-modified asphalt. The mass ratio of base asphalt to rubber powder is 80%:20%, and the amount of neutralizing agent added is 1.5% of the total amount of rubber asphalt.

[0095] The preparation process of the above-mentioned odor-free and environmentally friendly rubber-modified asphalt No. 2 is as follows: The base asphalt is heated to 155°C to obtain high-temperature base asphalt; The temperature of the high-temperature base asphalt was further increased to 170℃, rubber powder was added, and then the temperature was controlled at 185℃ for 60 minutes of preliminary modification to obtain rubber-modified asphalt. Add a neutralizing agent to rubber asphalt and catalyze the reaction for 70 minutes to obtain neutralizing rubber-modified asphalt. The mass ratio of base asphalt to rubber powder is 75%:25%, and the amount of neutralizing agent added is 2% of the total amount of rubber asphalt.

[0096] The preparation process of the above-mentioned odor-free and environmentally friendly rubber-modified asphalt No. 3 is as follows: The base asphalt is heated to 160℃ to obtain high-temperature base asphalt; The temperature of the high-temperature base asphalt was further increased to 180℃, rubber powder was added, and then the temperature was controlled at 200℃ for 40 minutes of preliminary modification to obtain rubber-modified asphalt. Add a neutralizing agent to rubber asphalt and catalyze the reaction for 80 minutes to obtain neutralizing rubber-modified asphalt. The mass ratio of base asphalt to rubber powder is 76%:24%, and the amount of neutralizing agent added is 1% of the total amount of rubber asphalt.

[0097] The preparation process of the above-mentioned odorless rubber-modified asphalt No. 4 is as follows: The base asphalt is heated to 160℃ to obtain high-temperature base asphalt; The temperature of the high-temperature base asphalt was further increased to 185℃, rubber powder was added, and then the temperature was controlled at 220℃ for 30 minutes of preliminary modification to obtain rubber-modified asphalt. Add a neutralizing agent to rubber asphalt and catalyze the reaction for 90 minutes to obtain neutralizing rubber-modified asphalt. The mass ratio of base asphalt to rubber powder is 75%:25%, and the amount of neutralizing agent added is 1% of the total amount of rubber asphalt.

[0098] The preparation process of the above-mentioned odorless rubber-modified asphalt No. 5 is as follows: The base asphalt is heated to 150°C to obtain high-temperature base asphalt; The temperature of the high-temperature base asphalt was further increased to 160℃, rubber powder was added, and then the temperature was controlled at 190℃ for 50 minutes of preliminary modification to obtain rubber-modified asphalt. Add a neutralizing agent to rubber asphalt and catalyze the reaction for 60 minutes to obtain neutralizing rubber-modified asphalt. The mass ratio of base asphalt to rubber powder is 80%:20%, and the amount of neutralizing agent added is 1.5% of the total amount of rubber asphalt.

[0099] The preparation process of rubber-modified asphalt D1# to rubber-modified asphalt D7# is the same as the preparation process of the above-mentioned odorless rubber-modified asphalt 3#.

[0100] Comparative performance tests were conducted on the above-prepared odor-free rubber-modified asphalt 1# to odor-free rubber-modified asphalt 5#, as well as rubber-modified asphalt D1# to rubber-modified asphalt D7#, and blank samples of rubber-modified asphalt without added odor-reducing agent prepared using base asphalt 70#A (Jinling Petrochemical) (prepared according to the proportions of Example 3). The test results are shown in Table 1: Table 1 Test Results As shown in Table 1, compared with the blank sample, the release of NMHC and VOCs was significantly reduced in both the neutralized rubber modified asphalt 1# to 5# containing neutralizing agents from Examples 1 to 5, and the rubber modified asphalt D1# to D7# containing neutralizing agents from Comparative Examples 1 to 7. However, there was little difference in softening point, penetration, and elastic recovery performance among the modified asphalts. This indicates that the neutralizing agents from Examples 1 to 5 and Comparative Examples 1 to 7 have no significant effect on the physical properties of the modified asphalt and do not affect the normal performance of the asphalt.

[0101] Further analysis of the NMHC and VOCs emissions of each group of modified asphalts revealed that the NMHC and VOCs emissions of the odorless rubber modified asphalts 1# to 5# were 210.15 mg / m³. 3 ~301.12mg / m 3 148.60 mg / m 3 ~212.45mg / m 3 Within the specified range, a comparison of rubber-modified asphalt D1# and D2# with odor-free rubber-modified asphalt 1# to 5# shows that the NMHC and VOCs emissions of rubber-modified asphalt D1# are 546.23 mg / m³. 3 and 390.18 mg / m 3 The NMHC and VOCs emissions of rubber-modified asphalt D2# were 406.45 mg / m³. 3 and 293.68 mg / m 3 The levels were significantly higher than those emitted by odor-neutralized rubber modified asphalt 1# to odor-neutralized rubber modified asphalt 5#. This indicates that the addition of citric acid powder can significantly promote the removal of harmful volatile gases from rubber asphalt by the odor neutralizer. Furthermore, apart from anhydrous citric acid powder or monohydrate citric acid powder, the effects of other acid powders (such as oxalic acid powder) are not ideal.

[0102] By comparing the performance of rubber-modified asphalt D3#, rubber-modified asphalt D4#, and odorless rubber-modified asphalt 1# to odorless rubber-modified asphalt 5#, it can be seen that the NMHC and VOC emissions of rubber-modified asphalt D3# are 448.15 mg / m³. 3 and 322.34 mg / m 3 The NMHC and VOCs emissions of rubber-modified asphalt D4# were 432.55 mg / m³. 3 and 313.16 mg / m 3 The levels of NMHC and VOCs emitted from odorless rubber-modified asphalt 1# to odorless rubber-modified asphalt 5# are significantly higher than those emitted from other types of asphalt. This indicates that the synergistic effect of microsilica powder and plant fruit powder is due to their simultaneous addition in order to effectively remove NMHC and VOCs.

[0103] Comparing the performance of rubber-modified asphalt D5# and odorless rubber-modified asphalt 1# to odorless rubber-modified asphalt 5#, it can be seen that the NMHC and VOC emissions of rubber-modified asphalt D5# are 329.56 mg / m³. 3 and 237.93 mg / m 3 The levels were significantly higher than those emitted from odorless rubber-modified asphalt 1# to odorless rubber-modified asphalt 5#, indicating that plant fruit powder is significantly more effective than natural plant extracts in removing NMHC and VOCs from modified asphalt.

[0104] By comparing the performance of rubber-modified asphalt D6#, rubber-modified asphalt D7#, and odorless rubber-modified asphalt 1# to odorless rubber-modified asphalt 5#, it can be seen that the NMHC and VOC emissions of rubber-modified asphalt D6# are 365.12 mg / m³. 3 and 256.45 mg / m 3 The NMHC and VOCs emissions of rubber-modified asphalt D7# were 395.78 mg / m³. 3 and 287.32 mg / m 3 This indicates that aluminum hydroxide and magnesium hydroxide have a synergistic effect and must be added simultaneously to further improve the removal of NMHC and VOCs.

[0105] In summary, the synergistic effect of the components in the road rubber modified asphalt neutralizer in Examples 1 to 5 of the present invention reduces the emissions of NMHC and VOCs in the modified asphalt, achieving excellent neutralization and environmental protection effects.

[0106] The emission indicators of the odorless and environmentally friendly asphalt fumes from Examples 1 to 5 were tested, and the test results are detailed in Table 2. Table 2 Detection Results As shown in Table 2, the emissions of SO2, H2S, NOx, and VOCs in the blank sample were 16.78 mg / m³. 3 5.87 mg / m 3 45.5 mg / m 3 532.68 mg / m 3 The SO2 emissions from odorless rubber-modified asphalt No. 1 to No. 5 are 0.12 mg / m³. 3 ~0.32mg / m 3 The H2S emission was 0.012 mg / m³. 3 ~0.051mg / m 3 NOx emissions were 2.14 mg / m³. 3 ~4.52mg / m 3 The VOC emissions were 148.60 mg / m³. 3 ~212.45mg / m 3 Therefore, compared with the blank sample, the content of SO2, H2S, NOx and VOCs emitted by the deodorizing rubber modified asphalt 1# to deodorizing rubber modified asphalt 5# with the addition of the deodorizing agent of the present invention was significantly reduced. This shows that the deodorizing agent of the present invention can significantly reduce the emission of harmful gases in rubber asphalt and achieve the effect of deodorizing rubber asphalt.

[0107] Test Example 2 Under laboratory conditions, the maximum NMHC data of the original rubber asphalt and the modified asphalt No. 3 were tracked and detected, and the emissions of non-methane total hydrocarbons (NMHC) and TVOC and the changes in the pungent odor of asphalt were compared between the two.

[0108] Experimental materials: IRPC70# asphalt, Jingbo Petrochemical 70# asphalt, each weighing 450g; rubber powder (provided by Shanxi Transportation Control Group, the rubber powder was added to IRPC70# asphalt and Jingbo Petrochemical 70# asphalt by external admixture method to obtain two types of rubber modified asphalt, the amount of rubber powder added was 112.5g); road rubber modified asphalt neutralizing agent as described in Example 3 (the neutralizing agent was added to the rubber asphalt by external admixture method, the amount of which was 5.625g).

[0109] The specific preparation process of the above-mentioned rubber asphalt is as follows: 1) Divide IRPC70# asphalt and Jingbo Petrochemical 70# asphalt into three parts respectively; and name them IRPC70# asphalt 1#, IRPC70# asphalt 2#, IRPC70# asphalt 3#, and Jingbo Petrochemical 70# asphalt 1#, Jingbo Petrochemical 70# asphalt 2#, and Jingbo Petrochemical 70# asphalt 3#. 2) Select the above six portions of asphalt, and heat each portion in a different electric heating jacket. When the temperature reaches 160℃, start stirring at 260 r / min. When the asphalt temperature reaches 180℃, add the rubber powder and increase the stirring speed to 600 r / min. After the rubber powder is added and completely immersed in the asphalt, control the temperature at 200℃ and stop stirring after 50 minutes of modification. Cover and start data testing after 10 minutes. Maintain stirring at 600 r / min until the end of the experiment to obtain IRPC70# rubber modified asphalt 1#, IRPC70# rubber modified asphalt 2#, IRPC70# rubber modified asphalt 3#, and Jingbo Petrochemical 70# rubber modified asphalt 1#, Jingbo Petrochemical 70# rubber modified asphalt 2#, and Jingbo Petrochemical 70# rubber modified asphalt 3#.

[0110] Experiment duration: 150 minutes were started after the rubber powder was added. NMHC data (highest value) of IRPC70# rubber-modified asphalt 1# and Jingbo Petrochemical 70# rubber-modified asphalt 1# were measured every 10 minutes. The flue gas detection data results for IRPC70# rubber-modified asphalt 1# are shown in Table 3, and those for Jingbo Petrochemical 70# rubber-modified asphalt 1# are shown in Table 6.

[0111] The road rubber-modified asphalt neutralizing agent described in Example 3 was added to IRPC70# rubber-modified asphalt 2#, IRPC70# rubber-modified asphalt 3#, and Jingbo Petrochemical 70# rubber-modified asphalt 2# and Jingbo Petrochemical 70# rubber-modified asphalt 3# prepared by the above method, respectively, to obtain IRPC70# neutral-odor rubber-modified asphalt 2#, IRPC70# neutral-odor rubber-modified asphalt 3#, and Jingbo Petrochemical 70# neutral-odor rubber-modified asphalt 2# and Jingbo Petrochemical 70# neutral-odor rubber-modified asphalt 3#. After adding the neutralizing agent, a timer was started for 150 minutes. NMHC data (maximum value) was measured every 10 minutes. The results are shown in Tables 4, 5, 7, and 8. The NMHC / TVOC comparison chart of the above six asphalt samples is shown in... Figure 5 and Figure 6 .

[0112] Table 3. Flue Gas Detection Data of IRPC70# Rubber Modified Asphalt No. 1 Table 4. Detection data of flue gas from IRPC70# odorless rubber modified asphalt No. 2. Table 5. Detection data of flue gas from IRPC70# odorless rubber modified asphalt No. 3. Based on the data in Tables 3-5 and Figure 5As can be seen, after adding the deodorizing agent for road rubber-modified asphalt described in Example 3, the emissions of NMHC and TVOC in asphalt during the production process can be effectively reduced; calculated using the lowest detection values: Compared to IRPC70# rubber-modified asphalt 1#, IRPC70# odor-neutralizing rubber-modified asphalt 2# exhibits a 58% reduction in non-methane total hydrocarbons (NMHC) and a 60.71% reduction in total TVOC. Similarly, IRPC70# odor-neutralizing rubber-modified asphalt 3#, compared to IRPC70# rubber-modified asphalt 1#, shows a reduction of approximately 58.78% in NMHC and a 61.31% reduction in TVOC. This demonstrates that the odor-neutralizing agent for road rubber-modified asphalt described in this invention can effectively reduce the volatilization of NMHC and TVOC in IRPC70# rubber-modified asphalt, preventing their release into the air and ensuring the environmental performance of the modified asphalt.

[0113] Table 6. Flue Gas Detection Data of No. 1 Flue Gas from Jingbo Petrochemical 70# Rubber Modified Asphalt Table 7. Flue Gas Detection Data of Jingbo Petrochemical 70# Odorless Rubber Modified Asphalt No. 2 Table 8. Detection Data of Flue Gas from No. 3 of Jingbo Petrochemical's 70# Odorless Rubber Modified Asphalt Through Tables 6-8 and Figure 6 As can be seen, after adding the deodorizing agent for road rubber-modified asphalt described in Example 3, Jingbo Petrochemical's 70# rubber-modified asphalt 1# can effectively reduce the emissions of NMHC and TVOC during the asphalt production process. Calculated using the lowest detection values: Jingbo Petrochemical's 70# deodorizing rubber-modified asphalt 2# reduces NMHC by approximately 61.99% and TVOC by approximately 62.57%; Jingbo Petrochemical's 70# deodorizing rubber-modified asphalt 3# reduces NMHC by approximately 63.08% and TVOC by approximately 63.93%. This indicates that the deodorizing agent for road rubber-modified asphalt described in this invention can effectively reduce the volatilization of NMHC and TVOC in rubber asphalt, prevent them from being released into the air, and ensure the performance of the modified asphalt.

[0114] In summary, as shown in Tables 3 to 8, when the amount of rubber powder added to Jingbo Petrochemical 70# rubber modified asphalt 1# and IRPC70# rubber modified asphalt 1# is 25% of the total amount of base asphalt, the amount of smoke is large and the pungent odor is strong; after adding the deodorizing agent for road rubber modified asphalt described in this invention, the amount of smoke and the pungent odor are significantly reduced.

[0115] The embodiments of this disclosure have been described above. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of this disclosure. The scope of this disclosure is defined by the appended claims and their equivalents. Various substitutions and modifications can be made by those skilled in the art without departing from the scope of this disclosure, and all such substitutions and modifications should fall within the scope of this disclosure.

Claims

1. A deodorizing agent for road rubber-modified asphalt, characterized in that, The neutralizing agent comprises, by weight percentage: 20%-50% aluminum hydroxide, 20%-50% magnesium hydroxide, 15%-30% silica fume, 5%-15% plant fruit powder, and 0.5%-1% citric acid powder.

2. The deodorizing agent for road rubber-modified asphalt according to claim 1, characterized in that, The particle size of the aluminum hydroxide, the magnesium hydroxide, and the microsilica powder is greater than or equal to 1250 mesh.

3. The deodorizing agent for road rubber-modified asphalt according to claim 1, characterized in that, The particle size of the plant fruit powder is greater than or equal to 1250 mesh.

4. The deodorizing agent for road rubber-modified asphalt according to claim 1, characterized in that, The plant-based fruit powder includes at least one of mango powder, peach powder, and apple powder.

5. A method for preparing a neutralizing agent for road rubber-modified asphalt, applied to the preparation of the neutralizing agent according to any one of claims 1-4, characterized in that, Includes the following steps: Weigh each component according to the composition and proportion of the road rubber modified asphalt neutralizer according to any one of claims 1-4; The aluminum hydroxide, magnesium hydroxide, and silica powder are mixed at 5℃-35℃ to obtain mixed system 1; The plant fruit powder is added to the mixing system 1 and stirred to obtain the mixing system 2; The citric acid powder is added to the mixture 2 and stirred to obtain the deodorizing agent for road rubber modified asphalt.

6. The preparation method according to claim 5, characterized in that, The stirring speed during the mixing of the aluminum hydroxide, magnesium hydroxide, and silica powder is 20-40 rpm, and the stirring time is 30-60 min; and / or, When the plant fruit powder is added to the mixing system 1, the stirring speed is 15 rpm-25 rpm, and the stirring time is 30 min-60 min; and / or, When adding the citric acid powder to the mixture 2, the stirring speed is 10 rpm-20 rpm and the stirring time is 30 min-60 min.

7. A method for preparing rubber-modified asphalt for roads, characterized in that, The preparation of the deodorizing agent according to any one of claims 1-4 includes the following process: The base asphalt is heated to 150℃-160℃ to obtain high-temperature base asphalt with good fluidity. When the temperature of the high-temperature matrix asphalt is further increased to 160℃-185℃, rubber powder is added, and the temperature is controlled at 185℃-220℃. The initial modification is carried out for ≥30 minutes to obtain rubber asphalt. Add the odor neutralizer according to any one of claims 1-4 to the rubber asphalt, and catalyze the reaction for 60-90 minutes to obtain odor neutralized road rubber modified asphalt.

8. The method according to claim 7, characterized in that, The mass ratio of the base asphalt to the rubber powder is (75-80):(20-25); the amount of the neutralizing agent added is 1%-2% of the mass of the rubber asphalt.

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