Odor-removing and smoke-suppressing asphalt modifier and method for asphalt pavement harmful substance emission

Abstract

The invention discloses an odorless smoke suppression asphalt modifier for asphalt pavement noxious substance emission and a method, and belongs to the technical field of asphalt pavement materials, the odorless smoke suppression asphalt modifier comprises the following components by mass: 37-42 parts of a surface modified zeolite molecular sieve, 45-53 parts of expanded graphite powder, and 10-18 parts of metal organic porous powder. Compared with common unmodified zeolite, the surface modified zeolite molecular sieve adopted by the invention can partially remove molecular sieve framework aluminum and remove deposit species in pore channels, increase the silica-alumina ratio and specific surface area of the molecular sieve, greatly improve the hydrophobicity of the molecular sieve, and further improve the adsorption performance of the molecular sieve. The expanded graphite has the advantages of loose porous structure, high specific surface area, good chemical stability, high temperature resistance and the like; compared with a traditional adsorption material, the metal organic porous powder has the large specific surface area, the adjustable pore structure and the high modifiability, the metal organic porous powder and the modified zeolite powder play a synergistic purification role, and the metal organic porous powder has the remarkable advantage on harmful substance gas adsorption.

Description

Technical Field

[0001] The present invention belongs to the technical field of asphalt pavement materials, and in particular relates to an odor-free and smoke-suppressing asphalt modifier and a method for controlling harmful emissions from asphalt pavements. Background Art

[0002] At present, asphalt pavement has been widely used in urban roads and highways, becoming the most paved high-grade pavement in China. However, during the construction and service process, especially during high-temperature construction, a large amount of complex asphalt fume is generated, which contains not only NO, which pollutes the air, but also X Toxic small molecules such as CO, SO2, volatile organic compounds (VOCs), and solid harmful particles (PM2.5, PM10.0) can cause irreversible damage to construction workers and the environment. Asphalt pavement also releases some harmful substances during operation, especially during high summer temperatures. Furthermore, the large number of vehicles on the road, and their exhaust emissions, especially those containing NOx and CO, can also cause certain air pollution, deteriorating the road environment.

[0003] To address these issues, current methods primarily use asphalt toxicant inhibitors, such as polymer-based odor modifiers, porous adsorbents, and inorganic powder modifiers. However, these methods offer low smoke and odor suppression rates and limited effectiveness. Furthermore, some raw materials exhibit poor compatibility and dispersibility with asphalt. Therefore, developing an asphalt modifier that can both reduce the volatilization of harmful gases and the emission of harmful particles is urgent. Summary of the Invention

[0004] The purpose of the present invention is to provide an odorless and smoke-suppressing asphalt modifier and method for controlling harmful emissions from asphalt pavements, thereby reducing the release of harmful substances during asphalt pavement construction and operation, and overcoming the shortcomings of the existing technology.

[0005] In order to achieve the above object, the present invention provides the following technical solutions: In a first aspect, the present invention provides an odor-free and smoke-suppressing asphalt modifier for reducing harmful emissions from asphalt pavement, comprising the following components in parts by mass: 37-42 parts of surface-modified zeolite molecular sieve, 45-53 parts of expanded graphite powder, and 10-18 parts of metal organic porous powder.

[0006] Furthermore, the surface-modified zeolite molecular sieve is one of natural clinoptilolite and ZSM-5 molecular sieve; and the metal organic porous powder is metal-based organic polymer powder.

[0007] Furthermore, the expanded graphite powder is obtained by high-rate expandable graphite powder being expanded at a high temperature, and the high temperature range is 700-1200°C.

[0008] In a second aspect, the present invention provides a method for preparing an odorless and smoke-suppressing asphalt modifier for reducing harmful emissions from asphalt pavement, comprising the following steps: Preparation of surface-modified zeolite molecular sieves; The zeolite molecular sieve is passed through a standard sieve and then washed with deionized water to obtain a shaken and washed zeolite molecule; soaking and drying the zeolite molecules after shaking and washing to obtain dried zeolite molecule powder; Adding an acid solution to the dried zeolite molecular powder and shaking it in a full-temperature shaking incubator to obtain a zeolite-acid solution; The zeolite acid solution is washed with deionized water and then dried to obtain a surface-modified zeolite molecular sieve; Preparation of asphalt modifier: 37-42 parts of the obtained surface-modified zeolite molecular sieve, 45-53 parts of expanded graphite powder, and 10-18 parts of metal organic porous powder are mixed to obtain a mixed powder, deionized water is added to the mixed powder, and the mixture is stirred and dissolved to obtain a deionized water-mixed powder suspension; Ultrasonic dispersion is performed on the deionized water-mixed powder suspension to obtain a suspension; The suspension is dried to a constant weight to obtain an asphalt modifier.

[0009] Further, The metal organic porous powder is a metal-based organic polymer powder, and the preparation process is as follows: Dissolve the metal source powder in methanol and stir until completely dissolved to obtain solution A; Dissolve 2-methylimidazole in methanol to obtain solution B; Slowly pour solution A into solution B, stir evenly, then place in a reactor and react in a water bath to obtain a suspension; The suspension was centrifuged and washed with deionized water to remove the reactants and obtain a clean powder; The cleaned powder is placed in a vacuum drying oven and dried to a constant weight to obtain a metal-based organic polymer powder.

[0010] Furthermore, the metal source powder is Zn(NO3) 2· 6H2O, the mass is 0.5g~0.8g; the amount of 2-methylimidazole is the same as Zn 2+ The amount of substance ratio is 1.4~1.8.

[0011] Furthermore, the preparation conditions of the metal organic porous powder are: the water bath reaction conditions are: temperature 30~50℃, time 8-10h; centrifugation conditions are: 8000rpm, time 10min; deionized water washing times are 2~3 times; drying conditions are temperature 60℃, time 12h.

[0012] Furthermore, in the modification preparation process of the zeolite molecular sieve: the zeolite molecular sieve is oscillated and washed with deionized water after passing through a standard sieve using a reciprocating gyroscopic oscillator, and the zeolite molecule oscillation time is 30 minutes to 1 hour; the number of washing times is 3 to 5 times; the soaking time is 8 to 12 hours, and the soaking temperature is 25°C; the drying temperature is 60 to 80°C, and the drying time is 10 hours.

[0013] Furthermore, the acid solution is one of hydrochloric acid and nitric acid; the molar concentration of the acid solution is 1.0 to 3.0 moL / L; the acid solution is added to the dried zeolite molecular powder and the powder is shaken in a full-temperature shaking incubator at a speed of 150 to 250 r / min for 3 to 5 hours.

[0014] Furthermore, the mass ratio of the mixed powder to deionized water is 1:15 to 1:20; Ultrasonic dispersion of deionized water-mixed powder suspension was performed using an ultrasonic disperser, and the ultrasonic dispersion time was 1 to 3 h; The suspension was dried in an oven at a temperature of 60°C for 20 to 24 hours.

[0015] Compared with the prior art, the present invention has the following beneficial technical effects: The present invention provides an odor-free and smoke-suppressing asphalt modifier for harmful emissions from asphalt pavements. The modifier is prepared using surface-modified zeolite molecular sieves, expanded graphite powder, and metal-organic porous powders. Compared to conventional unmodified zeolites, the surface-modified zeolite molecular sieves can partially remove aluminum from the molecular sieve framework and remove accumulated species in the pores, thereby increasing the molecular sieve's silicon-to-aluminum ratio and specific surface area, significantly improving its hydrophobicity, and thereby enhancing the molecular sieve's adsorption performance. Expanded graphite powder has the advantages of a loose porous structure, high specific surface area, good chemical stability, and high temperature resistance. Compared to traditional adsorption materials, metal-organic porous powders have a larger specific surface area, an adjustable pore structure, and are highly modifiable. They synergize with the modified zeolite powder to purify harmful gases, providing significant advantages.

[0016] The present invention is aimed at asphalt pavement and targets harmful emissions from asphalt pavement. It has obvious smoke suppression and odor removal functions, can effectively reduce the release of asphalt smoke during the mixing process of asphalt mixture and lower the mixing temperature, saving energy and reducing carbon emissions.

[0017] The present invention also discloses a method for preparing an odor-free, smoke-suppressing asphalt modifier for reducing harmful emissions from asphalt pavements. This method can achieve more uniform mixing of mixed powders of different properties, resulting in enhanced synergistic effects. It can also improve the compatibility of expanded graphite powder and metal-organic porous powder with asphalt, allowing for better dispersion within the asphalt. The asphalt modifier prepared by the present invention exhibits advantages such as high compatibility with asphalt materials, outstanding adsorption properties, and excellent thermal stability. It reduces harmful gas and particulate matter emissions from asphalt during construction, as well as vehicle exhaust emissions during service. This method truly targets harmful emissions from asphalt pavements, creating a healthier and more positive environment for the road environment and those working in it. Furthermore, the preparation process is simple, cost-effective, and easily scalable. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The present invention is a flow chart of a method for preparing an odor-free and smoke-suppressing asphalt modifier for reducing harmful emissions from asphalt pavement. DETAILED DESCRIPTION

[0019] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0020] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0021] The present invention provides an odor-free and smoke-suppressing asphalt modifier for reducing harmful emissions from asphalt pavement, comprising the following components in parts by mass: 37-42 parts of surface-modified zeolite molecular sieve, 45-53 parts of expanded graphite powder, and 10-18 parts of metal organic porous powder.

[0022] The features and performance of the present invention are further described in detail below with reference to the embodiments.

[0023] Example 1 The present invention provides an odor-free and smoke-suppressing asphalt modifier for reducing harmful emissions from asphalt pavement, comprising the following components in parts by mass: 37 parts of surface-modified zeolite molecular sieve, 53 parts of expanded graphite powder, and 10 parts of metal organic porous powder.

[0024] The surface-modified zeolite molecular sieve used is one of natural clinoptilolite and ZSM-5 molecular sieve; and the metal organic porous powder is metal-based organic polymer powder.

[0025] The expanded graphite powder used is high-rate expandable graphite powder that has been fully expanded at high temperature, and the high temperature range is 700-1200℃.

[0026] like Figure 1 As shown, the specific preparation method of the present invention of a odor-free and smoke-suppressing asphalt modifier for harmful emissions of asphalt pavement includes the following steps: Preparation of surface-modified zeolite molecular sieves; (1) The zeolite molecular sieve was passed through a 10-mesh standard sieve, added to a beaker containing deionized water, and placed in a reciprocating speed-adjustable multi-purpose oscillator with a power of 80W for 30 minutes, and then washed three times with the same deionized water to obtain the zeolite molecules after shaking and washing; (2) Soaking the zeolite molecules after shaking and washing in deionized water at 25°C for 8 hours and then drying them in an oven at 80°C for 10 hours to obtain dried zeolite molecule powder; (3) Add the dried zeolite molecular powder into a glass bottle containing 1.0 mol / L hydrochloric acid solution, then place it in a full-temperature shaking incubator and shake it at a rate of 150 r / min for 5 h to obtain a zeolite-containing acid solution; (4) Wash the obtained zeolite-containing acid solution twice with deionized water, dry it in an oven for 8 hours and store it to obtain a surface-modified zeolite molecular sieve, which is sealed and stored; Metal organic porous powder is metal-based organic polymer powder. Preparation of metal-based organic polymer powder: Take the metal source powder and dissolve it in methanol, stir until it is completely dissolved to obtain solution A; in this embodiment, the metal source powder is Zn(NO3) 2· 6H2O; Take 2-methylimidazole and dissolve it in methanol. The amount of 2-methylimidazole is equal to that of Zn 2+ The molar ratio of the substance is 1.4~1.8, and solution B is obtained; Slowly pour solution A into solution B, stir evenly, then place in a reactor and conduct water bath reaction to obtain a suspension; the water bath reaction conditions are: temperature 30-50℃, time 8-10h; The suspension was centrifuged and washed with deionized water at 8000 rpm for 10 min. The deionized water washing times were 2 to 3 times. The reactants were removed to obtain a clean powder. The cleaned powder was placed in a vacuum drying oven and dried to constant weight at a temperature of 60° C. for 12 h to obtain a metal-based organic polymer powder.

[0027] Preparation of asphalt modifier: (5) Weigh 37 parts of surface-modified zeolite molecular sieve, 53 parts of expanded graphite powder, and 10 parts of metal organic porous powder and mix them to obtain a mixed powder. Put deionized water with a mass 15 times that of the mixed powder into a beaker, slowly add the mixed powder into the beaker, and mix it thoroughly with a glass rod to obtain a deionized water-mixed powder suspension; (6) Place the deionized water-mixed powder suspension in an ultrasonic disperser and disperse it at a frequency of 100 Hz for 3 h to mix it evenly to obtain a suspension; (7) The suspension is placed in an oven and dried at 60°C for 20 h until constant weight is reached. The suspension is then taken out and sieved to obtain a odorless and smoke-suppressing asphalt modifier for harmful emissions from asphalt pavement.

[0028] Heat the asphalt to 135°C, then slowly add the prepared modifier into the asphalt while stirring, and pay attention to adding small amounts and multiple times to obtain modified asphalt.

[0029] Example 2 The present invention provides an odor-free and smoke-suppressing asphalt modifier for reducing harmful emissions from asphalt pavement, comprising the following components in parts by mass: 37 parts of surface-modified zeolite molecular sieve, 45 parts of expanded graphite powder, and 18 parts of metal organic porous powder.

[0030] The metal organic porous powder used is metal-based organic polymer powder, and the preparation method is the same as that in Example 1.

[0031] The expanded graphite powder used is high-rate expandable graphite powder that has been fully expanded at high temperature, and the high temperature range is 700-1200℃.

[0032] The preparation method of the odor-free and smoke-suppressing asphalt modifier for asphalt pavement harmful emissions in this embodiment is basically the same as the preparation method in Example 1, with the following differences: In step (1), the zeolite molecular sieve is passed through a 12-mesh standard sieve, added into a beaker containing deionized water, and placed in a reciprocating speed-adjustable multi-purpose oscillator with a power of 80W and oscillated for 45 minutes, and then washed four times with the same deionized water to obtain the zeolite molecules after oscillation and washing.

[0033] In step (2), the zeolite molecules after shaking and washing are soaked in deionized water at 25° C. for 10 hours and then placed in an oven at 80° C. for 10 hours to obtain dried zeolite molecule powder.

[0034] In step (3), the dried zeolite molecular powder is added to a glass bottle containing 1.5 mol / L hydrochloric acid solution, and then placed in a full-temperature shaking incubator and shaken at a rate of 200 r / min for 4 h to obtain a zeolite acid solution.

[0035] In step (6), the deionized water-mixed powder suspension is placed in an ultrasonic disperser, dispersed at a frequency of 110 Hz for 2 h, and mixed evenly to obtain a suspension.

[0036] In step (7), the suspension is placed in an oven, dried in an oven at 60° C. for 22 hours until constant weight is reached, and then taken out and sieved to obtain a odorless and smoke-suppressing asphalt modifier for harmful emissions from asphalt pavement.

[0037] Example 3 The present invention provides an odor-free and smoke-suppressing asphalt modifier for reducing harmful emissions from asphalt pavement, comprising the following components in parts by mass: 42 parts of surface-modified zeolite molecular sieve, 45 parts of expanded graphite powder, and 13 parts of metal organic porous powder.

[0038] The surface-modified zeolite molecular sieve used is one of natural clinoptilolite and ZSM-5 molecular sieve.

[0039] The metal organic porous powder used is metal-based organic polymer powder, and the preparation method is the same as that in Example 1.

[0040] The expanded graphite powder used is high-rate expandable graphite powder that has been fully expanded at high temperature, and the high temperature range is 700-1200℃.

[0041] The preparation method of the odor-free and smoke-suppressing asphalt modifier for asphalt pavement harmful emissions in this embodiment is basically the same as the preparation method in Example 1, with the following differences: (1) The zeolite molecular sieve was passed through a 15-mesh standard sieve, added to a beaker containing deionized water, and placed in a reciprocating speed-adjustable multi-purpose oscillator with a power of 80W for 1 hour. Then, it was washed 5 times with the same deionized water to obtain the zeolite molecules after oscillation and washing.

[0042] (2) The zeolite molecules after oscillation and washing were soaked in deionized water at 25°C for 12 hours and then placed in an oven at 80°C for 10 hours to obtain dried zeolite molecular powder.

[0043] (3) The dried zeolite molecular powder was added to a glass bottle containing 2.0 mol / L hydrochloric acid solution, and then placed in a full-temperature shaking incubator and shaken at a rate of 200 r / min for 4 h to obtain a zeolite-containing acid solution.

[0044] (6) Place the deionized water-mixed powder suspension in an ultrasonic disperser and disperse it at a frequency of 120 Hz for 2 h. Mix well to obtain a suspension.

[0045] (7) The suspension is placed in an oven and dried at 60°C for 24 hours until constant weight is reached. The suspension is then taken out and sieved to obtain a odorless and smoke-suppressing asphalt modifier for harmful emissions from asphalt pavement.

[0046] Example 4 The present invention provides an odor-free and smoke-suppressing asphalt modifier for reducing harmful emissions from asphalt pavement, comprising the following components in parts by mass: 42 parts of surface-modified zeolite molecular sieve, 48 parts of expanded graphite powder, and 10 parts of metal organic porous powder.

[0047] The surface-modified zeolite molecular sieve used is one of natural clinoptilolite and ZSM-5 molecular sieve.

[0048] The metal organic porous powder used is metal-based organic polymer powder, and the preparation method is the same as that in Example 1.

[0049] The expanded graphite powder used is high-rate expandable graphite powder that has been fully expanded at high temperature, and the high temperature range is 700-1200℃.

[0050] The preparation method of the odor-free and smoke-suppressing asphalt modifier for asphalt pavement harmful emissions in this embodiment is basically the same as the preparation method in Example 1, with the following differences: (1) The zeolite molecular sieve was passed through a 12-mesh standard sieve, added to a beaker containing deionized water, and placed in a reciprocating speed-adjustable multi-purpose oscillator with a power of 80W for 1 hour. Then, it was washed four times with the same deionized water to obtain the zeolite molecules after oscillation and washing.

[0051] (2) The zeolite molecules after oscillation and washing were soaked in deionized water at 25°C for 12 hours and then placed in an oven at 80°C for 10 hours to obtain dried zeolite molecular powder.

[0052] (3) The dried zeolite molecular powder was added to a glass bottle containing 2.0 mol / L hydrochloric acid solution, and then placed in a full-temperature shaking incubator and shaken at a rate of 250 r / min for 3 h to obtain a zeolite-containing acid solution.

[0053] (6) Place the deionized water-mixed powder suspension in an ultrasonic disperser and disperse it at a frequency of 120 Hz for 3 h. Mix it evenly to obtain a suspension.

[0054] (7) The suspension is placed in an oven and dried at 60°C for 20 h until constant weight is reached. The suspension is then taken out and sieved to obtain a odorless and smoke-suppressing asphalt modifier for harmful emissions from asphalt pavement.

[0055] Comparative Example 1 The present invention provides an odor-free and smoke-suppressing asphalt modifier for reducing harmful emissions from asphalt pavement, comprising the following components in parts by mass: 42 parts of unsurface-modified zeolite molecular sieve, 45 parts of expanded graphite powder, and 13 parts of metal organic porous powder. The unsurface-modified zeolite molecular sieve is either natural clinoptilolite or ZSM-5 molecular sieve. The metal organic porous powder is a metal-based organic polymer powder. The preparation method is the same as in Example 1. The expanded graphite powder is made by fully expanding high-temperature, high-rate expandable graphite powder.

[0056] The preparation method of the odor-free and smoke-suppressing asphalt modifier for reducing harmful emissions from asphalt pavement in this embodiment is the same as the preparation method in Example 1.

[0057] Comparative Example 2 The present invention provides an odor-free and smoke-suppressing asphalt modifier for reducing harmful emissions from asphalt pavement, comprising the following components in parts by mass: 42 parts of surface-modified zeolite molecular sieve, 48 parts of expanded graphite powder, and 10 parts of metal organic porous powder.

[0058] The surface-modified zeolite molecular sieve is one of natural clinoptilolite or ZSM-5 molecular sieve, and the metal organic porous powder used is metal-based organic polymer powder. The preparation method is the same as that of Example 1. The expanded graphite powder is a high-rate expandable graphite powder that is fully expanded at high temperature.

[0059] The preparation method of the odor-free and smoke-suppressing asphalt modifier for asphalt pavement harmful emissions in this embodiment is basically the same as the preparation method in Example 1, with the following differences: (1) The zeolite molecular sieve was passed through a 12-mesh standard sieve, added to a beaker containing deionized water, and placed in a reciprocating speed-adjustable multi-purpose oscillator with a power of 80W for 1 hour. Then, it was washed four times with the same deionized water to obtain the zeolite molecules after oscillation and washing.

[0060] (2) The zeolite molecules after oscillation and washing were soaked in deionized water at 25°C for 12 hours and then placed in an oven at 80°C for 10 hours to obtain dried zeolite molecular powder.

[0061] (3) The dried zeolite molecular powder was added to a glass bottle containing 2.5 mol / L hydrochloric acid solution, and then placed in a full-temperature shaking incubator and shaken at a rate of 200 r / min for 4 h to obtain a zeolite-containing acid solution.

[0062] (6) The deionized water-mixed powder suspension was placed in an ultrasonic disperser and dispersed at a frequency of 110 Hz for 2.5 h. The mixture was mixed evenly to obtain a suspension.

[0063] (7) Place the suspension in an oven and dry it at 60°C for 22 hours until constant weight is reached. Then take it out and sieve it to obtain a odorless and smoke-suppressing asphalt modifier for asphalt pavement harmful emissions. Performance Testing 1. Basic performance indicators of modified asphalt: Referring to the T 0610-2011 method of the "Test Procedures for Asphalt and Asphalt Mixtures in Highway Engineering", basic performance indicators such as needle penetration, softening point and ductility of modified asphalt were tested, and the dosage of the odorless and smoke-suppressing asphalt modifier was 10%.

[0064] Table 1 Basic properties of odorless and smoke-suppressing asphalt

[0065] As shown in Table 1, the modified asphalt exhibits lower penetration and higher softening points compared to the base asphalt and the comparative example, demonstrating that the examples of the present invention can improve the high-temperature performance of asphalt. While the ductility at 10°C decreases slightly, the decrease is relatively small, indicating that the modified asphalt outperforms the base asphalt and the comparative example at high temperatures.

[0066] 2. Harmful gas emission reduction performance test The handheld gas detector based on the PID principle was used to test the harmful gas emissions of different asphalts at 160°C through indoor experiments, thereby verifying the emission reduction effect of the present invention. The specific experimental data are shown in Table 2.

[0067] Table 2 Harmful gas emissions from modified asphalt

[0068] As can be seen from the table, the modified asphalt examples of the present invention outperformed both the base asphalt and the comparative examples in reducing H2S, TVOC, and SO2 emissions. In particular, Example 4 exhibited the lowest emission concentrations across all indicators, with reductions reaching 62.5%, 67.48%, and 77.14%, respectively, demonstrating the best modification results. This suggests that the modification method of Example 4 is more effective in reducing harmful gas emissions and is more environmentally friendly.

[0069] 3. Harmful particulate matter emission reduction performance test Based on a handheld particulate matter detector, indoor experiments were conducted to test the harmful gas emissions of different asphalts at 160°C, thereby verifying the emission reduction effect of the present invention. The specific experimental data are shown in Table 3.

[0070] Table 3 Harmful particulate matter emissions from modified asphalt

[0071] It can be seen from Table 3 that, compared with the emission concentration of harmful asphalt particles released by the base asphalt and the control example after 30 minutes, all embodiments of the present invention can effectively reduce the emission of harmful asphalt particles PM2.5, PM5.0 and PM10.0, indicating that they can effectively reduce the emission of harmful asphalt particles during the construction process of asphalt mixture such as mixing, storage, paving, and the service process of asphalt pavement.

[0072] 4. Exhaust gas purification test Following the T 0610-2011 method in the "Test Procedures for Asphalt and Asphalt Mixtures in Highway Engineering," asphalt mixture rutting slabs measuring 300 mm × 300 mm × 50 mm were formed. Exhaust gas degradation tests were conducted indoors using a custom-made exhaust gas degradation chamber. To ensure consistency in temperature, humidity, and other factors, exhaust gas of equal concentrations was introduced into the chamber beforehand. After 30 minutes, the changes in NOx, HC, CO2, and CO concentrations were measured. The results are shown in Table 4 below.

[0073] Table 4 Automobile exhaust purification results

[0074] It can be seen from Table 4 that compared with the asphalt NOx, HC, CO2 and CO released by the base asphalt and the control example after 30 minutes, all the embodiments of the present invention can effectively reduce the concentration of asphalt exhaust gas, and can effectively reduce the exhaust gas in the road environment of the asphalt pavement during service.

[0075] In summary, by comparing Example 4 with Comparative Example 1, it can be found that the modified zeolite has a better effect on reducing harmful emissions, and by comparing Example 4 with Comparative Example 2, it can be found that the effect is also better after the preparation method of the present invention is used.

[0076] The present invention provides an odor-free and smoke-suppressing asphalt modifier for harmful emissions from asphalt pavements and a preparation method thereof, which is made of the following raw materials: zeolite molecular sieve, expanded graphite, and metal organic porous powder. The odor-free and smoke-suppressing asphalt modifier provided by the present invention has obvious odor-free, smoke-suppressing, and exhaust gas removal functions, which can effectively reduce the release of harmful gases and harmful particulate matter from asphalt during the mixing process of asphalt mixtures, reduce the irritating odor generated by asphalt mixtures during the mixing, paving, and other construction processes, and the exhaust gas from the road surface during service, effectively improve the road environment, and provide a healthier environment for road workers. At the same time, the odor-free and smoke-suppressing asphalt modifier for harmful emissions from asphalt pavements provided by the present invention will not have an adverse effect on the performance of the asphalt mixture itself.

[0077] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered by the scope of protection of the claims of the present invention.

Claims

1. A odorless and smoke-suppressing asphalt modifier for harmful emissions from asphalt pavement, characterized in that: Calculated by mass, it includes the following components: 37-42 parts of surface-modified zeolite molecular sieve, 45-53 parts of expanded graphite powder, and 10-18 parts of metal organic porous powder.

2. The odorless and smoke-suppressing asphalt modifier for reducing harmful emissions from asphalt pavement according to claim 1, characterized in that: The surface-modified zeolite molecular sieve is one of natural clinoptilolite and ZSM-5 molecular sieve; and the metal organic porous powder is metal-based organic polymer powder.

3. The odorless and smoke-suppressing asphalt modifier for reducing harmful emissions from asphalt pavement according to claim 1, characterized in that: Expanded graphite powder is made by high-rate expandable graphite powder after high-temperature expansion, and the high-temperature range is 700-1200℃.

4. A method for preparing an odorless and smoke-suppressing asphalt modifier for reducing harmful emissions from asphalt pavement, characterized in that: The following processes are included: Preparation of surface-modified zeolite molecular sieves; The zeolite molecular sieve is passed through a standard sieve and then washed with deionized water to obtain a shaken and washed zeolite molecule; soaking and drying the zeolite molecules after shaking and washing to obtain dried zeolite molecule powder; Adding an acid solution to the dried zeolite molecular powder and shaking it in a full-temperature shaking incubator to obtain a zeolite-acid solution; The zeolite acid solution is washed with deionized water and then dried to obtain a surface-modified zeolite molecular sieve; Preparation of metal organic porous powder; Preparation of asphalt modifier: 37-42 parts of the obtained surface-modified zeolite molecular sieve, 45-53 parts of expanded graphite powder, and 10-18 parts of metal organic porous powder are mixed to obtain a mixed powder, deionized water is added to the mixed powder, and the mixture is stirred and dissolved to obtain a deionized water-mixed powder suspension; Ultrasonic dispersion is performed on the deionized water-mixed powder suspension to obtain a suspension; The suspension is dried to a constant weight to obtain an asphalt modifier.

5. The method for preparing a odorless and smoke-suppressing asphalt modifier for reducing harmful emissions from asphalt pavement according to claim 4, characterized in that: The metal organic porous powder is a metal-based organic polymer powder, and the preparation process is as follows: Dissolve the metal source powder in methanol and stir until completely dissolved to obtain solution A; Dissolve 2-methylimidazole in methanol to obtain solution B; Slowly pour solution A into solution B, stir evenly, then place in a reactor and react in a water bath to obtain a suspension; The suspension was centrifuged and washed with deionized water to remove the reactants and obtain a clean powder; The cleaned powder is placed in a vacuum drying oven and dried to a constant weight to obtain a metal-based organic polymer powder.

6. The method for preparing a odorless and smoke-suppressing asphalt modifier for reducing harmful emissions from asphalt pavement according to claim 5, characterized in that: The metal source powder is Zn(NO3) 2· 6H2O, the mass is 0.5g~0.8g; the amount of 2-methylimidazole is the same as Zn 2+ The amount of substance ratio is 1.4~1.

8.

7. The method for preparing a odorless and smoke-suppressing asphalt modifier for reducing harmful emissions from asphalt pavement according to claim 5, characterized in that: The preparation conditions of the metal organic porous powder are as follows: water bath reaction conditions: temperature 30-50°C, time 8-10h; centrifugation conditions: 8000rpm, time 10min; deionized water washing times 2-3 times; drying conditions: temperature 60°C, time 12h.

8. The method for preparing a odorless and smoke-suppressing asphalt modifier for reducing harmful emissions from asphalt pavement according to claim 5, characterized in that: The modified preparation process of the zeolite molecular sieve is as follows: after the zeolite molecular sieve passes through a standard sieve, it is oscillated and washed with deionized water using a reciprocating gyroscopic oscillator, and the zeolite molecular sieve oscillation time is 30 minutes to 1 hour; the washing times are 3 to 5 times; the soaking time is 8 to 12 hours, and the soaking temperature is 25°C; the drying temperature is 60 to 80°C, and the drying time is 10 hours.

9. The method for preparing a odorless and smoke-suppressing asphalt modifier for reducing harmful emissions from asphalt pavement according to claim 5, characterized in that: The acid solution is one of hydrochloric acid and nitric acid; the molar concentration of the acid solution is 1.0 to 3.0 moL / L; the acid solution is added to the dried zeolite molecular powder and the powder is shaken in a full-temperature shaking incubator at a speed of 150 to 250 r / min for 3 to 5 hours.

10. The method for preparing a odorless and smoke-suppressing asphalt modifier for reducing harmful emissions from asphalt pavement according to claim 5, characterized in that: The mass ratio of the mixed powder to deionized water is 1:15-1:20; Ultrasonic dispersion of deionized water-mixed powder suspension was performed using an ultrasonic disperser, and the ultrasonic dispersion time was 1 to 3 h; The suspension was dried in an oven at a temperature of 60°C for 20 to 24 hours.

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