Modifier, modified asphalt for reducing pollution and carbon emissions and tail gas purification, and preparation method thereof

Abstract

The present invention provides a modifier for reducing pollution and carbon emissions and purifying tail gas, a modified asphalt and a preparation method. The modifier includes: TaCl5, Ba(OH)2·8H2O, sodium decahydrododecaborate, indium selenide, fly ash and ceramic polishing powder. The modified asphalt includes: road asphalt, a modifier for reducing pollution and carbon emissions and purifying tail gas, a dispersant and a silane coupling agent. The modifier for reducing pollution and carbon emissions and purifying tail gas of the present invention has a porous structure, a pyroelectric effect and a high thermoelectric conductivity. The porous structure can not only effectively adsorb harmful substances in asphalt fume and automobile tail gas, but also provide space for loading barium tantalate and indium selenide. The spontaneous polarization effect of the modifier for reducing pollution and carbon emissions and purifying tail gas further reduces and degrades pollutants in asphalt fume and automobile tail gas, enhancing the pollution reduction, carbon emission reduction and tail gas purification efficacy of the asphalt pavement throughout its life cycle. Moreover, both barium tantalate and indium selenide can absorb ultraviolet rays, effectively improving the anti-ultraviolet aging ability of the modified asphalt.

Description

Technical Field

[0001] The present invention belongs to the technical field of road materials, relates to modified asphalt, and specifically relates to a modifier, modified asphalt and preparation method for reducing pollution, carbon emissions and purifying vehicle exhaust. Background Art

[0002] In the construction of high-grade highways in China, asphalt pavements are usually adopted. With the development of economic policies, many low-grade highways are beginning to transform from cement concrete pavements to asphalt concrete pavements. However, it is difficult to avoid pollutant emissions during the construction and operation of asphalt pavements. During the construction stage, a large amount of flue gas is generated by hot mix asphalt mixture, polluting the environment. During the operation stage, problems such as the emission of volatile harmful substances and vehicle exhaust from asphalt pavements, and the main components of its pollutants are three categories: VOCs, solid particulate matter, and inorganic small molecule gases. At present, the research on reducing pollutant emissions from asphalt pavements is mostly based on the construction stage of asphalt pavements. For example, emulsified asphalt or modifiers are used to reduce the temperature of asphalt during the construction process, thereby playing a role in reducing pollutant emissions. However, there is almost no research on reducing pollutant emissions during the operation stage of asphalt pavements. Therefore, it is necessary to conduct research on reducing pollution, carbon emissions and purifying vehicle exhaust based on the whole life cycle of asphalt pavement construction, operation and maintenance. Summary of the Invention

[0003] Aiming at the deficiencies of the existing technology, the purpose of the present invention is to provide a modifier, modified asphalt and preparation method with the functions of reducing pollution, carbon emissions and purifying vehicle exhaust, and solve the problem that it is difficult for existing modified asphalt to achieve pollution reduction and carbon emission reduction throughout the life cycle.

[0004] To solve the above technical problems, the present invention is implemented by adopting the following technical solutions:

[0005] A modifier for reducing pollution, carbon emissions and purifying vehicle exhaust is made from the following raw materials: TaCl5, Ba(OH)2·8H2O, disodium decahydrodiborate, indium selenide, fly ash and ceramic polishing powder.

[0006] The present invention also has the following technical features:

[0007] Preferably, in the modifier for reducing pollution, carbon emissions and purifying vehicle exhaust, the mass ratio of TaCl5, Ba(OH)2·8H2O, disodium decahydrodiborate, indium selenide, fly ash and ceramic polishing powder is 0.4:0.8:0.2:1:3:1.

[0008] The present invention also protects a preparation method of the modifier for reducing pollution, carbon emissions and purifying vehicle exhaust as described above. The method is carried out according to the following steps:

[0009] Step 1, pretreatment of raw materials of the modifier for reducing pollution, carbon emissions and purifying vehicle exhaust:

[0010] Add fatty acid polyoxyethylene ester to indium selenide-deionized water solution, react at room temperature for 12 h, stir once every 1 h. After the reaction is completed, filter out the indium selenide powder, place it in an oven at 60 °C to dry, sieve it, and store it for later use.

[0011] Place disodium decahydrodecaborate in deionized water solution, add isoceteth-20, ultrasonically disperse for 20 min, take the lower-layer suspension, and store it for later use; take ceramic polishing brick powder, put it into an oven at 100 °C to dehydrate and dry for 2 h, then place it in a ball mill, with the ball milling speed of 150 rpm and the ball milling time of 1 h to obtain ceramic polishing brick powder with a particle size of 20 - 30 μm.

[0012] Step 2, preparation of nano-modified barium tantalate:

[0013] Weigh TaCl5 and dissolve it in ethanol, stir for 1 h until the solution is clear, then continue to add Ba(OH)2·8H2O and stir for 1 h; place the obtained solution in a hydrothermal reaction kettle, with the reaction temperature of 220 °C and the reaction duration of 20 h. Centrifuge and wash the obtained product, dry it in an oven at 100 °C to constant weight, and grind and sieve it to obtain barium tantalate powder.

[0014] Place the disodium decahydrodecaborate solution and barium tantalate powder in a planetary high-energy ball mill, with the ball milling speed of 200 rpm and the ball milling time of 2 h to obtain a disodium decahydrodecaborate / barium tantalate powder solution; take out the ball-milled disodium decahydrodecaborate / barium tantalate powder solution, place it in an oven at 160 °C to dry to constant weight, take out the dried solid product, grind and sieve it to obtain nano-modified barium tantalate powder.

[0015] Step 3, preparation of solid waste-based porous carrier:

[0016] Weigh fly ash and ceramic polishing brick powder and place them in a beaker, prepare a fly ash / ceramic polishing brick powder-deionized water solution with deionized water, place the fly ash / ceramic polishing brick powder-deionized water solution in an ultrasonic disperser, and set the ultrasonic wave to 50 HZ and ultrasonically disperse for 2 h.

[0017] Place the obtained solution in an oven at 180 °C to dry to constant weight, grind and sieve it to obtain fly ash / ceramic polishing brick powder composite powder.

[0018] Place the fly ash / ceramic polishing brick powder composite powder into a box-type electric furnace, control the temperature at 800 °C, and keep it warm for 2 h. Crush and sieve the obtained product to obtain a solid waste-based porous carrier.

[0019] Step 4, preparation of pollution reduction, carbon emission reduction and tail gas purification modifier:

[0020] After mixing the nano-modified barium tantalate powder and indium selenide powder, an appropriate amount of ethanol is added and stirred into an ethanol suspension. Then, a solid waste-based porous carrier is added, and the mixture is continuously stirred with an electric stirrer and dried in a blast drying oven at 100 °C for 3 h. The dried sample is placed in a box-type resistance furnace and heated to 500 °C with a holding time of 3 h to obtain a pollution reduction, carbon emission reduction, and tail gas purification modifier.

[0021] The present invention also protects a modified asphalt, which is made from the following raw materials: road asphalt, a pollution reduction, carbon emission reduction, and tail gas purification modifier, a dispersant, and a silane coupling agent.

[0022] The pollution reduction, carbon emission reduction, and tail gas purification modifier used is the one described above.

[0023] Specifically, in terms of mass parts, it is made from the following raw materials: 80 parts of road asphalt, 10 - 20 parts of the pollution reduction, carbon emission reduction, and tail gas purification modifier, 1 - 4 parts of the dispersant, and 4 - 6 parts of the coupling agent.

[0024] Preferably, in terms of mass parts, it is made from the following raw materials: 80 parts of road asphalt, 20 parts of the pollution reduction, carbon emission reduction, and tail gas purification modifier, 4 parts of the dispersant, and 6 parts of the coupling agent.

[0025] Preferably, the road asphalt is 70# base asphalt, 90# base asphalt, SBS modified asphalt, or crumb rubber modified asphalt.

[0026] Preferably, the dispersant is isocetyl polyoxyethylene ether, fatty alcohol polyalkoxy ether, fatty acid polyoxyethylene ester, or isotridecyl polyoxyethylene ether.

[0027] Preferably, the coupling agent is a silane coupling agent or a phthalate coupling agent.

[0028] A preparation method of the modifier described above, which is carried out according to the following steps: heating the road asphalt to 140 °C, slowly adding the pollution reduction, carbon emission reduction, and tail gas purification modifier and the silane coupling agent into the road asphalt, first stirring at a low speed with a stirrer for 10 min with a shear rate of 800 - 1200 rpm, and then shearing at a high speed with a shearer for 30 min with a shear rate of 3000 - 3500 rpm to obtain a modified asphalt with the functions of pollution reduction, carbon emission reduction, and tail gas purification.

[0029] The pollution reduction, carbon emission reduction, and tail gas purification modifier used is prepared by the preparation method of the pollution reduction, carbon emission reduction, and tail gas purification modifier described above.

[0030] Compared with the prior art, the present invention has the following technical effects:

[0031] (Ⅰ) The pollution reduction, carbon emission reduction and tail gas purification modifier of the present invention has a porous structure, pyroelectric effect and high thermoelectric conductivity. The porous structure can not only effectively adsorb harmful substances in asphalt fumes and automobile tail gases, but also provide space for loading barium tantalate and indium selenide. The spontaneous polarization effect of the pollution reduction, carbon emission reduction and tail gas purification modifier further reduces and degrades pollutants in asphalt fumes and automobile tail gases, enhancing the pollution reduction, carbon emission reduction and tail gas purification efficacy throughout the life cycle of asphalt pavement. Moreover, both barium tantalate and indium selenide can absorb ultraviolet light, effectively improving the anti-ultraviolet aging ability of the modified asphalt.

[0032] (Ⅱ) In the pollution reduction, carbon emission reduction and tail gas purification modifier of the present invention, indium selenide and barium tantalate have synergistic effects in the process of degrading organic compounds. The degradation of organic compounds mainly relies on three active species: H + , ·OH, ·O2 - . However, due to the relatively wide band gap and narrow light response range of barium tantalate, its photocatalytic efficiency is relatively low. After being modified by disodium decahydrodecaborate, under the synergistic action of indium selenide with a relatively narrow band gap, the carrier transport is changed, the light absorption range is expanded, and the photocatalytic degradation efficiency is thus improved. At the same time, barium tantalate mainly absorbs ultraviolet light, while the spectral response range of indium selenide covers the range from ultraviolet to infrared, further improving the photocatalytic efficiency of the pollution reduction, carbon emission reduction and tail gas purification modifier. The electric field generated by the polarization of indium selenide and barium tantalate can not only adsorb pollutants through electroadsorption, but also synergistically enhance the intermolecular force between fly ash and polluted particles, greatly improving the adsorption capacity of the pollution reduction, carbon emission reduction and tail gas purification modifier for pollutants.

[0033] (Ⅲ) In the pollution reduction, carbon emission reduction and tail gas purification modifier of the present invention, the addition of ceramic polished brick powder avoids the high sintering temperature of SiC for pore formation, reduces the production cost and consumes solid waste. By heating the composite powder, the organic polymer flocculant in it burns and calcium magnesium calcium carbonate decomposes to generate gas, forming a porous composite powder structure.

[0034] (Ⅳ) The modified asphalt prepared by the present invention with the functions of pollution reduction, carbon emission reduction and tail gas purification can achieve efficient and long-term absorption and purification of pollutants throughout the whole cycle of the construction stage and operation stage of asphalt pavement, reduce greenhouse gas emissions, lower energy consumption, and relieve the pressure on road service and the ecological environment. Description of the Drawings

[0035] Figure 1(a) shows the test results of the penetration and softening point of the modified asphalt in Examples 1 to 5.

[0036] Figure 1(b) shows the test results of the ductility of the modified asphalt in Examples 1 to 5.

[0037] Figure 2(a) shows the comparison of the penetration before and after aging of Example 2 and Comparative Examples 5, 6, and 7.

[0038] Figure 2(b) shows the comparison of softening points before and after aging between Example 2 and Comparative Examples 5, 6, and 7.

[0039] Figure 2(c) shows the comparison of ductility before and after aging between Example 2 and Comparative Examples 5, 6, and 7.

[0040] Figure 3(a) shows the test results of the emission reduction rates of Examples 1 to 5.

[0041] Figure 3(b) shows the test results of the tail gas purification rates of Examples 1 to 5.

[0042] Figure 4(a) is a comparison chart of the emission reduction rates between Example 2 and Comparative Examples 1 to 4.

[0043] Figure 4(b) is a comparison chart of the tail gas purification rates between Example 2 and Comparative Examples 1 to 4.

[0044] The following further elaborates on the specific content of the present invention in conjunction with examples. Specific Embodiments

[0045] It should be noted that all raw materials in the present invention, unless otherwise specified, are all known raw materials in the prior art.

[0046] Following the above technical solutions, the following are specific examples of the present invention. It should be noted that the present invention is not limited to the following specific examples, and all equivalent transformations made on the basis of the technical solutions of this application fall within the protection scope of the present invention.

[0047] Example 1:

[0048] This example provides a modified asphalt with pollution reduction, carbon emission reduction, and tail gas purification functions. Calculated by mass fraction, it is made from the following raw materials: 80 parts of road asphalt, 15 parts of pollution reduction, carbon emission reduction, and tail gas purification modifier, 2 parts of dispersant, and 5 parts of coupling agent.

[0049] This example also provides a pollution reduction, carbon emission reduction, and tail gas purification modifier, which is made from the following raw materials: the mass ratio of TaCl5, Ba(OH)2·8H2O, disodium decahydrododecaborate, indium selenide, fly ash, and ceramic polishing powder is 0.4:0.8:0.2:1:3:1.

[0050] In this example, the road asphalt is 70# base asphalt.

[0051] In this example, the dispersant is fatty acid polyoxyethylene ester.

[0052] In this example, the coupling agent is a silane coupling agent.

[0053] This example also provides a preparation method for the above-mentioned pollution reduction, carbon emission reduction, and tail gas purification modified asphalt, and this method is carried out according to the following steps:

[0054] Step 1, Pretreatment of raw materials of the pollution reduction, carbon emission reduction and tail gas purification modifier:

[0055] Add fatty acid polyoxyethylene ester to indium selenide-deionized water solution, react at room temperature for 12 h, stir once every 1 h. After the reaction is completed, filter out the indium selenide powder, place it in an oven at 60 °C for drying, sieve it, and store it for later use.

[0056] Place disodium decahydrododecaborate in deionized water solution, add isoceteth-20, disperse it ultrasonically for 20 min, take the lower layer suspension, and store it for later use.

[0057] Take ceramic polishing brick powder, put it into an oven at 100 °C for dehydration and drying for 2 h, then place it in a ball mill, the ball mill speed is 150 rpm, and the ball milling time is 1 h to obtain ceramic polishing brick powder with a particle size of 20-30 μm.

[0058] Step 2, Preparation of nano-modified barium tantalate:

[0059] Weigh TaCl5 and dissolve it in ethanol, stir for 1 h until the solution is clear, and continue to add an appropriate amount of Ba(OH)2·8H2O and stir for 1 h. Place the obtained solution in a hydrothermal reaction kettle, the reaction temperature is 220 °C, the reaction duration is 20 h, centrifuge and wash the obtained product, dry it in an oven at 100 °C to constant weight, and grind and sieve it to obtain barium tantalate powder.

[0060] Place the disodium decahydrododecaborate solution and barium tantalate powder in a planetary high-energy ball mill, the ball mill speed is 200 rpm, and the ball milling time is 2 h to obtain a disodium decahydrododecaborate / barium tantalate powder solution; take out the ball-milled disodium decahydrododecaborate / barium tantalate powder solution, and place it in an oven at 160 °C for drying to constant weight, take out the dried solid product, grind and sieve it to obtain nano-modified barium tantalate powder.

[0061] Step 3, Preparation of solid waste-based porous carrier:

[0062] Weigh fly ash and ceramic polishing brick powder and place them in a beaker, prepare a fly ash / ceramic polishing brick powder-deionized water solution with deionized water, place the fly ash / ceramic polishing brick powder-deionized water solution in an ultrasonic disperser, and set the ultrasonic wave to 50 HZ and disperse it ultrasonically for 2 h.

[0063] Place the obtained solution in an oven at 180 °C for drying to constant weight, grind and sieve it to obtain fly ash / ceramic polishing brick powder composite powder.

[0064] Put the fly ash / ceramic polishing brick powder composite powder into a box-type electric furnace, control the temperature at 800 °C, and the heat preservation time is 2 h. Grind and sieve the obtained product to obtain a solid waste-based porous carrier.

[0065] Step 4, Preparation of pollution reduction, carbon emission reduction and tail gas purification modifier:

[0066] After mixing the nano-modified barium tantalate powder and indium selenide powder, add an appropriate amount of ethanol and stir to form an ethanol suspension. Then add the solid waste-based porous carrier and continuously stir with an electric stirrer. Dry it in a forced-air drying oven at 100 °C for 3 h. Place the dried sample in a box-type resistance furnace and heat it to 500 °C, with a holding time of 3 h, to obtain the pollution reduction, carbon emission reduction and tail gas purification modifier.

[0067] Step 5, Preparation of pollution reduction, carbon emission reduction and tail gas purification modified asphalt:

[0068] Heat the road asphalt to 140 °C, and slowly add the pollution reduction, carbon emission reduction and tail gas purification modifier and silane coupling agent to the road asphalt. First, stir it at a low speed for 10 min with a stirrer, with a shear rate of 800 - 1200 rpm, and then shear it at a high speed for 30 min with a shearer, with a shear rate of 3000 - 3500 rpm, to prepare the modified asphalt with the functions of pollution reduction, carbon emission reduction and tail gas purification.

[0069] Example 2:

[0070] A modified asphalt with the functions of pollution reduction, carbon emission reduction and tail gas purification given in this example is made from the following raw materials by mass: 80 parts of road asphalt, 20 parts of pollution reduction, carbon emission reduction and tail gas purification modifier, 4 parts of dispersant, and 6 parts of coupling agent.

[0071] The pollution reduction, carbon emission reduction and tail gas purification modifier in this example is the same as that in Example 1.

[0072] The selection and specifications of the raw materials in this example are the same as those in Example 1.

[0073] The preparation method of the pollution reduction, carbon emission reduction and tail gas purification modified asphalt in this example is the same as that in Example 1.

[0074] Example 3:

[0075] A modified asphalt with the functions of pollution reduction, carbon emission reduction and tail gas purification given in this example is made from the following raw materials by mass: 80 parts of road asphalt, 10 parts of pollution reduction, carbon emission reduction and tail gas purification modifier, 1 part of dispersant, and 4 parts of coupling agent.

[0076] The pollution reduction, carbon emission reduction and tail gas purification modifier in this example is the same as that in Example 1.

[0077] The selection and specifications of the raw materials in this example are the same as those in Example 1.

[0078] The preparation method of the pollution reduction, carbon emission reduction and tail gas purification modified asphalt in this example is the same as that in Example 1.

[0079] Example 4:

[0080] A modified asphalt with pollution reduction, carbon emission reduction and tail gas purification functions given in this example is made from the following raw materials in parts by mass: 80 parts of road asphalt, 18 parts of pollution reduction, carbon emission reduction and tail gas purification modifier, 3 parts of dispersant, and 5 parts of coupling agent.

[0081] The pollution reduction, carbon emission reduction and tail gas purification modifier in this example is the same as that in Example 1.

[0082] The selection and specifications of the raw materials in this example are the same as those in Example 1.

[0083] The preparation method of the pollution reduction, carbon emission reduction and tail gas purification modified asphalt in this example is the same as that in Example 1.

[0084] Example 5:

[0085] A modified asphalt with pollution reduction, carbon emission reduction and tail gas purification functions given in this example is made from the following raw materials in parts by mass: 80 parts of road asphalt, 15 parts of pollution reduction, carbon emission reduction and tail gas purification modifier, 2 parts of dispersant, and 5 parts of coupling agent.

[0086] The pollution reduction, carbon emission reduction and tail gas purification modifier in this example is the same as that in Example 1.

[0087] The selection and specifications of the raw materials in this example are the same as those in Example 1.

[0088] The preparation method of the pollution reduction, carbon emission reduction and tail gas purification modified asphalt in this example is the same as that in Example 1.

[0089] Comparative Example 1:

[0090] A modified asphalt given in this comparative example has a main formula basically the same as that in Example 2, and the only difference is that in this comparative example, barium tantalate is not modified with disodium decahydrododecaborate, and barium tantalate of equal mass is used to replace disodium decahydrododecaborate.

[0091] The selection and specifications of the raw materials in this comparative example are the same as those in Example 2.

[0092] The preparation method of the modified asphalt in this comparative example is basically the same as that in Example 2.

[0093] Comparative Example 2:

[0094] A modified asphalt given in this comparative example has a main formula basically the same as that in Example 2, and the only difference is that in this comparative example, only fly ash is used as the porous carrier, and fly ash of equal mass is used to replace ceramic polishing powder.

[0095] In this comparative example, the selection and specifications of the raw materials are the same as those in Example 2.

[0096] The preparation method of the modified asphalt in this comparative example is basically the same as that in Example 2.

[0097] Comparative Example 3:

[0098] A modified asphalt given in this comparative example has a main formulation basically the same as that in Example 2, except that indium selenide is not added in this comparative example, and barium tantalate powder of equal mass is used to replace indium selenide.

[0099] In this comparative example, the selection and specifications of the raw materials are the same as those in Example 2.

[0100] The preparation method of the modified asphalt in this comparative example is basically the same as that in Example 2.

[0101] Comparative Example 4:

[0102] A modified asphalt given in this comparative example has a main formulation basically the same as that in Example 2, except that barium tantalate is not added in this comparative example, and indium selenide of equal mass is used to replace barium tantalate powder.

[0103] In this comparative example, the selection and specifications of the raw materials are the same as those in Example 2.

[0104] The preparation method of the modified asphalt in this comparative example is basically the same as that in Example 2.

[0105] Comparative Example 5:

[0106] This comparative example gives an asphalt, namely 70# asphalt, and a commercially available product can be specifically used.

[0107] Comparative Example 6:

[0108] This comparative example gives an asphalt, namely SBS modified asphalt, and a commercially available product can be specifically used.

[0109] Comparative Example 7:

[0110] This comparative example gives an asphalt, namely SBR modified asphalt, and a commercially available product can be specifically used.

[0111] Performance test:

[0112] The performance test of pollution reduction, carbon emission reduction and tail gas purification modified asphalt includes three parts: the basic performance test of modified asphalt, the emission reduction effect test and the purification effect test. According to the test procedures of "Highway Engineering Asphalt and Asphalt Mixtures" (JTGE20-2011), the three major indicators of pollution reduction, carbon emission reduction and tail gas purification modified asphalt before and after ultraviolet aging are measured, and the asphalt fume emission reduction rate and vehicle exhaust purification rate of asphalt pavement in the construction stage and operation stage are calculated to explore the environmental effects such as emission reduction and purification of pollution reduction, carbon emission reduction and tail gas purification modified asphalt.

[0113] First, basic performance:

[0114] Analysis Figures 1(a) to 2(c) , the basic road performance such as penetration, ductility and softening point of modified asphalt with pollution reduction, carbon emission reduction and tail gas purification functions before ultraviolet aging is close to that of 70# base asphalt, meeting the relevant technical requirements of "Technical Specifications for Construction of Highway Asphalt Pavement" (JTG F40-2004), and can be actually applied to the field of road engineering.

[0115] Analysis Figures 2(a) to 2(c) , after ultraviolet aging, the pollution reduction, carbon emission reduction and tail gas purification modified asphalt has a smaller penetration reduction, softening point increment and ductility reduction compared with 70# base asphalt, SBS modified asphalt and SBR modified asphalt, indicating that it has better high and low temperature stability and good anti-ultraviolet aging ability. This is because bismuth oxide and tourmaline are added to the modifier, which can effectively absorb ultraviolet rays, thus realizing the anti-ultraviolet aging function of modified asphalt.

[0116] Second, emission reduction effect:

[0117] To comprehensively evaluate the emission reduction effect of pollution reduction, carbon emission reduction and tail gas purification modified asphalt in the whole life cycle, the emission reduction effects in the construction stage, operation stage and maintenance stage of asphalt pavement are evaluated respectively. The calculation method of the emission reduction rate of asphalt mixture in different stages is shown in Equation Ⅰ, and the test results are shown in Figure 3(a) and Figure 4(a).

[0118]

[0119] In the formula:

[0120] E is the asphalt fume emission reduction rate of self-cleaning modified asphalt mixture in different stages.

[0121] c0 is the asphalt fume emission concentration of ordinary hot mix asphalt mixture in different stages.

[0122] c1 is the asphalt fume emission concentration of self-cleaning modified asphalt mixture in different stages.

[0123] Analyzing Figure 3(a), the asphalt fume emission reduction rate in the construction stage of asphalt pavement in Examples 1 to 5 is 52% - 61%, the emission reduction rate in the operation stage is 55 - 62%, and the emission reduction rate in the maintenance stage is 38 - 41%.

[0124] It shows that the pollution reduction, carbon emission reduction and tail gas purification modified asphalt has good ability to reduce the emissions of pollutants such as asphalt fume, and the emission reduction rates in the construction stage and operation stage are both greater than 50%, while the emission reduction rate in the maintenance stage is reduced by 10% - 20%. The reason for this result may be that as the amount of harmful substances adsorbed by the solid waste-based porous material increases, some harmful substances are difficult to degrade, occupying part of the pore structure, resulting in a significant reduction in the emission reduction rate in the maintenance stage.

[0125] Comparing Examples 1 - 5, Example 2 has the best emission reduction rates of asphalt fume and various pollutants in the construction, operation and maintenance stages. The emission reduction rate in the construction stage is 56%, the emission reduction rate in the operation stage is 62%, and the emission reduction rate in the maintenance stage is 41%.

[0126] Analyzing Figure 4(a), in Comparative Example 1, the polarization effect of barium tantalate is weakened due to the lack of nano-modification, resulting in a decrease in the overall emission reduction rate. In Comparative Example 2, the attenuation amplitude of the emission reduction rate is the largest. The reason for this result may be that only fly ash is used to load barium tantalate and indium selenide, and ceramic polishing powder is not added, failing to form a better porous structure, resulting in a decrease in the loading rate and a reduction in the amount of adsorbed pollutants, leading to the largest overall attenuation amplitude. The emission reduction rates of Comparative Example 3 and Comparative Example 4 are reduced by up to 50% compared with the examples. This may be because only barium carbonate or indium selenide is used to play the degradation role, and no synergistic effect is formed during the process of barium tantalate and indium selenide degrading pollutants, resulting in a significant reduction in the efficiency of degrading pollutants.

[0127] Third, tail gas purification efficacy:

[0128] The tail gas purification efficacy refers to the absorption and degradation effect on the main gaseous pollutants such as CO X , HC and NO X etc. in vehicle exhaust during the operation period of the asphalt pavement. To determine the tail gas purification efficacy of the pollution reduction, carbon emission reduction and tail gas purification modified asphalt developed by the present invention, the tail gas concentration before and after absorption and degradation by the modified asphalt mixture is measured, and the purification rate is calculated according to Equation II. The test results are shown in Figures 3(b) and 4(b).

[0129]

[0130] In the formula:

[0131] T is the purification rate of vehicle exhaust.

[0132] f0 is the initial emission concentration of vehicle exhaust.

[0133] f1 is the concentration of vehicle exhaust after absorption and degradation by the self-cleaning modified asphalt mixture.

[0134] As can be seen from Figure 3(b), the tail gas purification rates of Examples 1 to 5 are all greater than 60%, indicating that indium selenide and barium tantalate after nano-modification have good tail gas purification functions. The tail gas purification efficiency of Example 2 is the highest, reaching 65%. Considering its asphalt fume emission reduction rate comprehensively, Example 2 is preferably selected as the optimal solution for the optimal pollution reduction, carbon reduction and tail gas purification modifier: 75 parts of road asphalt, 20 parts of pollution reduction, carbon reduction and tail gas purification modifier, 4 parts of dispersant, and 6 parts of coupling agent. The mass ratio of TaCl5, Ba(OH)2·8H2O, disodium decahydrododecaborate, indium selenide, fly ash and ceramic polishing waste residue is 0.4:0.8:0.2:1:3:1.

[0135] As can be seen from Figure 4(b), the tail gas purification rates of Comparative Examples 1 to 4 are in the order of Comparative Example 1 > Comparative Example 2 > Comparative Example 3 > Comparative Example 4, which is similar to the law of asphalt fume emission reduction rate. This may be because some components in asphalt fume are the same as those in vehicle exhaust. By analyzing Comparative Examples 1 to 2 and Comparative Examples 3 to 4, it is not difficult to find that when only barium tantalate or indium selenide is used as the pollutant degradation material, the tail gas purification rate is significantly lower than that when the two substances are used for degradation simultaneously, further illustrating the synergistic effect of barium tantalate and indium selenide in the process of degrading pollutants.

Claims

1. A pollutant reduction, carbon emission reduction and tail gas purification modifier, characterized in that, It is made from the following raw materials: TaCl5, Ba(OH)2·8H2O, disodium decahydrodecaborate, indium selenide, fly ash and ceramic polishing brick powder; In the pollution reduction, carbon reduction and tail gas purification modifier, the mass ratio of TaCl5, Ba(OH)2·8H2O, disodium decahydrodecaborate, indium selenide, fly ash and ceramic polishing brick powder is 0.4:0.8:0.2:1:3:

1.

2. A preparation method of a pollution reduction, carbon emission reduction and tail gas purification modifier as described in claim 1, characterized in that, This method is carried out according to the following steps: Step 1, pretreatment of raw materials of the pollution reduction, carbon reduction and tail gas purification modifier: Add fatty acid polyoxyethylene ester to the indium selenide-deionized water solution, react at room temperature for 12 h, stir once every 1 h, filter out the indium selenide powder after the reaction is completed, place it in an oven at 60 °C to dry, sieve and store for later use; Place disodium decahydrodecaborate in a deionized water solution, add isocetyl polyoxyethylene ether, ultrasonically disperse for 20 min, take the lower layer suspension and store for later use; Take the ceramic polishing brick powder, put it into an oven at 100 °C to dehydrate and dry for 2 h, then place it in a ball mill, the ball milling speed is 150 rpm, and the ball milling time is 1 h to obtain ceramic polishing brick powder with a particle size of 20-30 μm; Step 2, preparation of nano-modified barium tantalate: Weigh TaCl5 and dissolve it in ethanol, stir for 1 h until the solution is clear, and then continue to add Ba(OH)2·8H2O and stir for 1 h; Place the obtained solution in a hydrothermal reaction kettle, the reaction temperature is 220 °C, and the reaction duration is 20 h. Centrifuge and wash the obtained product, dry it in an oven at 100 °C to constant weight, and grind and sieve to obtain barium tantalate powder; Place the disodium decahydrodecaborate solution and barium tantalate powder in a planetary high-energy ball mill, the ball milling speed is 200 rpm, and the ball milling time is 2 h to obtain a disodium decahydrodecaborate / barium tantalate powder solution; Take out the ball-milled disodium decahydrodecaborate / barium tantalate powder solution and place it in an oven at 160 °C to dry to constant weight. Take out the dried solid product, grind and sieve it to obtain nano-modified barium tantalate powder; Step 3, preparation of solid waste-based porous carrier: Weigh fly ash and ceramic polishing brick powder and place them in a beaker, prepare a fly ash / ceramic polishing brick powder-deionized water solution with deionized water, and place the fly ash / ceramic polishing brick powder-deionized water solution in an ultrasonic disperser, and set the ultrasonic wave to 50 HZ and ultrasonically disperse for 2 h; Place the obtained solution in an oven at 180 °C to dry to constant weight, grind and sieve to obtain fly ash / ceramic polishing brick powder composite powder; Put the fly ash / ceramic polishing brick powder composite powder into a box-type electric furnace, control the temperature at 800 °C, and keep the temperature for 2 h. Grind and sieve the obtained product to obtain a solid waste-based porous carrier; Step 4, preparation of the pollution reduction, carbon reduction and tail gas purification modifier: After mixing the nano-modified barium tantalate powder and indium selenide powder, add an appropriate amount of ethanol and stir to form an ethanol suspension. Then add the solid waste-based porous carrier and continuously stir with an electric stirrer, and dry in a blast drying oven at 100 °C for 3 h; Heat the dried sample in a box-type resistance furnace to 500 °C and keep the temperature for 3 h to obtain the pollution reduction, carbon reduction and tail gas purification modifier.

3. A modified asphalt, characterized in that, It is made from the following raw materials by mass fraction: 80 parts of road asphalt, 10 - 20 parts of pollution reduction, carbon reduction and tail gas purification modifier, 1 - 4 parts of dispersant, and 4 - 6 parts of coupling agent; The pollution reduction, carbon reduction and tail gas purification modifier described above uses the pollution reduction, carbon reduction and tail gas purification modifier described in claim 1.

4. The modified asphalt according to claim 3, characterized in that, It is made from the following raw materials by mass fraction: 80 parts of road asphalt, 20 parts of pollution reduction, carbon reduction and tail gas purification modifier, 4 parts of dispersant, and 6 parts of coupling agent.

5. The modified asphalt according to claim 3, characterized in that, The road asphalt described above is 70# base asphalt, 90# base asphalt, SBS modified asphalt or crumb rubber modified asphalt.

6. The modified asphalt according to claim 3, wherein, The dispersant described above is isomeric hexadecanol polyoxyethylene ether, fatty alcohol polyalkoxy ether, fatty acid polyoxyethylene ester or isomeric tridecanol polyoxyethylene ether.

7. The modified asphalt according to claim 3, characterized in that, The coupling agent described above is silane coupling agent or phthalate coupling agent.

8. A method for preparing the modified asphalt according to any one of claims 3 to 7, characterized in that, This method is carried out according to the following steps: heat the road asphalt to 140 °C, slowly add the pollution reduction, carbon reduction and tail gas purification modifier and silane coupling agent into the road asphalt, first stir at a low speed for 10 min with a stirrer, the shear rate is 800 - 1200 rpm, then use a shearer to shear at a high speed for 30 min, the shear rate is 3000 - 3500 rpm, to obtain the modified asphalt with the functions of pollution reduction, carbon reduction and tail gas purification.

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