Odor-free asphalt additive, odor-free asphalt and preparation method of odor-free asphalt

Abstract

The invention discloses an odorless asphalt additive, odorless asphalt and a preparation method thereof. The odorless asphalt additive comprises the following components in parts by weight: 1-5 parts of an auxiliary odorless agent; 1-5 parts of a modified slow-release odor-removing microcapsule; 1-10 parts of a dispersant; the modified slow-release odorless microcapsule comprises a shell material and a core material, the shell material is a composite shell material comprising silicon dioxide / nano tourmaline / polydopamine, the core material comprises one or more of ketones, esters, aldehydes and ethers, and a metal chelate is loaded on the surface of the shell material. According to the invention, the odorless asphalt additive containing the modified slow-release odorless microcapsule is added into the asphalt, so that the purposes of efficiently and durably reducing the content of irritant gas in asphalt smoke and emitting pleasant fragrance are achieved by virtue of the slow-release effect of the microcapsule, meanwhile, the odorless asphalt additive also has good pavement performance, and a brand new thought is provided for environment-friendly utilization of the asphalt.

Description

Technical Field

[0001] The invention belongs to the field of environmentally friendly asphalt, and specifically relates to a deodorizing asphalt additive, deodorizing asphalt and a preparation method thereof. Background Art

[0002] Asphalt pavement is the most important type of traffic road at present, and the hot mix and hot paving process is mainly used in its production and construction process. However, asphalt materials will release a large amount of toxic, harmful and irritating smoke into the air due to high temperatures during storage and transportation, which will not only pollute the environment, bring challenges to the survival of animals and plants, but also affect human health. Relevant studies have shown that asphalt smoke is mainly composed of low molecular weight and medium molecular weight hydrocarbons and hydrocarbon derivatives, mainly PAHs, nitrogen-containing compounds and sulfur-containing compounds, including strong carcinogens such as benzo[a]pyrene and gases with pungent odors such as NH3, H2S, and thiophene. Therefore, it is very necessary to carry out relevant research on asphalt smoke emission reduction.

[0003] At present, the most commonly used technology for controlling asphalt fume pollution is warm mix asphalt technology. Warm mix asphalt technology essentially enables asphalt mixtures to be mixed, spread and compacted at relatively low temperatures to achieve the purpose of saving energy and reducing fume emissions. Representative technologies include organic viscosity reduction warm mix technology, surfactant warm mix technology, asphalt foaming warm mix technology, etc. However, due to the addition of water and additives, the high temperature performance, low temperature performance and water damage resistance of the asphalt pavement will be reduced, and the service life of the asphalt pavement will be reduced. In addition, the cost of warm mix asphalt technology is relatively high, so it is difficult to popularize. Summary of the invention

[0004] In view of the problems existing in the prior art, the present invention provides a deodorizing asphalt additive, deodorizing asphalt and a preparation method thereof. The deodorizing asphalt additive is prepared by adding modified slow-release deodorizing microcapsules to asphalt. The deodorizing asphalt additive can effectively and permanently reduce the irritating gas content in asphalt smoke and emit a pleasant aroma by virtue of the slow-release effect of the microcapsules. At the same time, it also has good road performance, providing a new idea for the environmentally friendly use of asphalt.

[0005] The first aspect of the present invention provides a deodorizing asphalt additive, comprising the following components in parts by weight:

[0006] Auxiliary deodorant, 1-5 parts;

[0007] Modified sustained-release odorless microcapsules, 1-5 parts;

[0008] Dispersant, 1-10 parts;

[0009] The modified sustained-release odor-free microcapsule comprises a shell material and a core material, wherein the shell material is a composite shell material comprising silica / nano-tourmaline / polydopamine, the core material comprises one or more of ketones, esters, aldehydes, and ethers, and the surface of the shell material is loaded with a metal chelate.

[0010] Furthermore, the auxiliary deodorant is selected from one or more of maleimide compounds having more than 4 carbon atoms or antioxidants having more than 20 carbon atoms.

[0011] Furthermore, the maleimide compound having a carbon number greater than 4 is selected from one or more of N-phenylmaleimide, 6-(maleimido)hexanoic acid succinimide ester, tris(2-maleimidoethyl)amine, and N-(2-hydroxyethyl)maleimide.

[0012] Further, the antioxidant with a carbon number greater than 20 is a hindered phenol antioxidant and / or an aromatic acid antioxidant with a boiling point greater than 300°C. The hindered phenol antioxidant with a carbon number greater than 20 is selected from one or more of 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, 2,6-di-tert-butyl-p-methylphenol, and 2,6-di-tert-butyl-p-methylphenol. The aromatic acid antioxidant with a boiling point greater than 300°C is selected from one or more of 3-(3,5-dimethyl-4-hydroxyphenyl)acrylic acid, 3-(3,5-dimethoxy-4-hydroxyphenyl)acrylic acid, and 3-(3-methoxy-4-hydroxyphenyl)acrylic acid.

[0013] Furthermore, the dispersant is one or more of dodecyl dimethyl betaine and 1-hydroxyethyl-carboxymethyl-alkyl imidazoline.

[0014] Furthermore, the particle size of the modified sustained-release odor-free microcapsules is 1-5 μm.

[0015] Furthermore, the mass ratio of the shell material to the core material of the modified sustained-release odor-free microcapsule is 1:(0.5-2).

[0016] Furthermore, the shell material of the modified sustained-release odor-free microcapsule is a composite shell material comprising silica / nano-tourmaline / polydopamine, wherein the mass ratio of silica to nano-tourmaline is (1-5):1, and the mass ratio of silica to polydopamine shell material is 1:(0.1-0.5).

[0017] Furthermore, the surface of the shell material is loaded with a metal chelate, wherein the metal is preferably copper.

[0018] Furthermore, the surface of the shell material is loaded with metal chelates, and the metal loading accounts for 0.1wt%-15wt% of the total mass of the sustained-release odor-free microcapsules.

[0019] Furthermore, the ketones are aliphatic ketones having a carbon number greater than 4; the aliphatic ketones having a carbon number greater than 4 are selected from one or more of 3-hydroxy-2-butanone, 2,3-butanedione, and 3-pentene-2-one.

[0020] Furthermore, the esters are selected from fatty acid esters with a carbon number greater than 5 and lactones with a carbon number greater than 5; the fatty acid esters with a carbon number greater than 5 are selected from one or more of butyl acetate, isoamyl acetate, leaf acetate, leaf isobutyrate, ethyl isovalerate, butyl caproate, ethyl laurate, and ethyl caprylate; the lactones with a carbon number greater than 5 are selected from one or more of γ-valerolactone, γ-caprolactone, γ-octanolactone, and γ-nonanolactone.

[0021] Furthermore, the aldehydes are selected from aromatic aldehydes having a carbon number greater than 6 and terpene aldehydes having a carbon number greater than 8; the aromatic aldehydes having a carbon number greater than 6 are selected from one or more of benzaldehyde, phenylacetaldehyde, o-methoxy-p-methylbenzaldehyde, and 2-methyl-3-(3,4-methylenedioxyphenyl)propanal; the terpene aldehydes having a carbon number greater than 8 are selected from one or more of citral, citronellal, and hydroxycitronellal.

[0022] Furthermore, the ethers are aromatic ethers having a carbon number greater than 9; the aromatic ethers having a carbon number greater than 9 are selected from one or more of 4-hydroxy-3-methylallylbenzene and 4-propenylanisole.

[0023] Furthermore, the preparation method of the modified sustained-release odor-free microcapsules comprises the following steps:

[0024] S1: mixing nano tourmaline powder, a surfactant and a solvent, modifying the mixture under stirring, washing the mixture after modification, and freeze-drying the mixture to obtain modified nano tourmaline powder;

[0025] S2: stirring and mixing one or more of ketones, esters, aldehydes, and ethers to obtain a core material mixed liquid;

[0026] S3: adding the solvent and the modified nano-tourmaline powder obtained in step S1 to the core material mixed solution obtained in step S2, and stirring and mixing;

[0027] S4: adding the shell material precursor to the reaction system in step S3, stirring and mixing, and obtaining a Pickering emulsion;

[0028] S5: adjusting the pH value of the Pickering emulsion obtained in step S4 to 2-5, continuing stirring, then aging, filtering, and freeze-drying;

[0029] S6: adding the solid powder obtained in step S5 to a buffer solution, adding dopamine hydrochloride, treating under stirring, and then filtering, washing, and freeze-drying;

[0030] S7: adding the solid powder obtained in step S6 to the metal ion salt-formamide solution, treating under stirring, filtering, washing, and freeze-drying after the reaction is completed, to obtain the modified sustained-release odor-free microcapsules.

[0031] Furthermore, in step S1, the diameter of the nano-tourmaline powder is 10-100 nm.

[0032] Furthermore, the surfactant in step S1 is a cationic surfactant, preferably one or more of dodecyldimethylbenzylammonium chloride, hexadecyltrimethylammonium bromide, and octadecyltrimethylammonium chloride.

[0033] Furthermore, in step S1, the solvent is an aprotic solvent with a boiling point > 100°C, preferably one or more of formamide, N,N-dimethylformamide, dimethylacetamide, and dimethylphosphoramide, and more preferably formamide.

[0034] Furthermore, in step S1, the mass ratio of the nano-tourmaline powder to the surfactant is (1-10):1, and the mass ratio of the solvent to the surfactant is (10-50):1.

[0035] Furthermore, in step S1, the stirring speed is 400-600 rpm; the modification temperature is 100-200° C., and the modification time is 4-10 hours.

[0036] Furthermore, in step S1, the freeze-drying conditions are: vacuum drying at a temperature of -40°C to -20°C for 4-8 hours.

[0037] Furthermore, in step S2, the stirring speed is 400-600 rpm, the stirring temperature is 30-70° C., and the stirring time is 3-10 minutes.

[0038] Furthermore, in step S3, the solvent is an aprotic solvent with a boiling point > 100°C, preferably one or more of formamide, N,N-dimethylformamide, dimethylacetamide, and dimethylphosphoramide, and more preferably formamide.

[0039] Furthermore, in step S3, the mass ratio of the core material mixture to the modified nano-tourmaline powder is (1-10): 1. The mass ratio of the solvent to the modified nano-tourmaline powder is (20-60): 1.

[0040] Furthermore, in step S3, the stirring speed is 400-600 rpm, the stirring temperature is 40-60° C., and the stirring time is 4-6 hours.

[0041] Furthermore, in step S4, the shell material precursor is a silicate compound, preferably one or more of methyl silicate, ethyl orthosilicate, tetraethyl orthosilicate, and butyl orthosilicate, and more preferably ethyl orthosilicate.

[0042] Furthermore, in step S4, the mass ratio of the core material mixed liquid to the shell material precursor is (0.5-2):1.

[0043] Furthermore, in step S4, the stirring speed is 400-600 rpm, the stirring temperature is 40-60° C., and the stirring time is 4-6 hours.

[0044] Furthermore, in step S5, the pH value can be adjusted by using dilute acid, such as dilute hydrochloric acid. The stirring speed is 400-600 rpm, the stirring temperature is 40-60° C., and the stirring time is 4-6 hours.

[0045] Furthermore, in step S5, the aging condition is: standing at 40-60°C for 12-30 hours. The freeze-drying condition is: vacuum drying at a temperature of -40--20°C for 4-8 hours.

[0046] Furthermore, in step S6, the buffer is one or more of phosphate buffer, carbonate buffer, and Tris buffer, preferably Tris buffer.

[0047] Furthermore, in step S6, the pH value of the buffer solution is 8-10.

[0048] Furthermore, in step S6, the mass ratio of the buffer solution to the solid powder obtained in step S5 is (30-100):1.

[0049] Furthermore, in step S6, after adding dopamine hydrochloride, the mass concentration of dopamine in the reaction system is 2-8 mg / mL.

[0050] Furthermore, in step S6, the stirring speed is 100-300 rpm, the stirring temperature is 20-30° C., and the stirring time is 12-24 h.

[0051] Furthermore, in step S6, the freeze-drying conditions are: vacuum drying at a temperature of -40°C to -20°C for 4-8 hours.

[0052] Furthermore, in step S7, the solid powder obtained after freeze-drying in step S6 is dispersed in a metal ion salt-formamide solution, and ultrasonic dispersion can be used.

[0053] Further, in step S7, the metal ion salt is preferably a copper ion salt, and more preferably anhydrous copper sulfate.

[0054] Furthermore, in step S7, in the metal ion salt-formamide solution, the mass ratio of the metal ion salt to formamide is (0.5-1.5):1.

[0055] Furthermore, in step S7, the mass ratio of the metal ion salt-formamide solution to the solid powder obtained in step S7 is (5-20):1.

[0056] Furthermore, in step S7, the stirring speed is 200-450 rpm, the stirring temperature is 100-180° C., and the stirring time is 2-5 hours.

[0057] Furthermore, in step S7, the freeze-drying conditions are: vacuum drying at a temperature of -40°C to -20°C for 4-8 hours.

[0058] Furthermore, the auxiliary deodorizing agent is added to the dispersant, and the mixture is stirred at 400-500 rpm for 1-3 hours at 25-45° C., and then the modified sustained-release deodorizing microcapsules are added, and stirring is continued for 1-2 hours to obtain the deodorizing asphalt additive.

[0059] The second aspect of the present invention provides a deodorized asphalt, comprising the following components by weight:

[0060] Base asphalt, 50-500 parts;

[0061] The above-mentioned odorless asphalt additive, 1-50 parts.

[0062] Furthermore, the base asphalt is commercially available No. 50, No. 70 and No. 90 road asphalt, preferably No. 70 Grade A asphalt.

[0063] Furthermore, the base asphalt is heated to 133-153° C., the odor-free asphalt additive is added at a rotation speed of 400-600 rpm, and stirred for 2-4 hours to obtain the odor-free asphalt.

[0064] Compared with the prior art, the present invention has the following advantages:

[0065] (1) The modified slow-release odor-free microcapsules contained in the odor-free asphalt additive of the present invention have a composite shell material with three functions. The first function is that during the preparation process, nano-tourmaline acts as a template for the synthesis of microcapsules, which can maintain the stability of the core material precursor; the second function is that during the copper ion modification of the microcapsule composite shell material, a large amount of copper ions are adsorbed onto the surface of the microcapsules with the help of the negative ion field released by the nano-tourmaline powder under high temperature conditions, effectively increasing the metal ion loading capacity of the microcapsule shell material, and further improving the smoke suppression ability of the modified slow-release odor-free microcapsules; the third function is that during the asphalt mixing process, the nano-tourmaline powder contained in the shell material of the modified slow-release odor-free microcapsules will release a negative ion field under the action of high temperature, further attracting the compounds released by the asphalt under the action of high temperature to the surrounding of the modified slow-release odor-free microcapsules, while increasing the difficulty of these compounds to volatilize, and at the same time, the metal ions on the surface of the microcapsules and the odor-free core material components of the microcapsules can react with more of the above-mentioned compounds, thereby effectively reducing the impact of the irritating gases released from the asphalt pavement on the human body.

[0066] (2) The modified slow-release odor-free microcapsules added to the odor-free asphalt of the present invention can slowly release the core material - the odor-free active component after being added to the asphalt. When the odor-free active component is slowly released to the surface of the microcapsule shell material, it can undergo a nucleophilic reaction with the compounds with pungent odor in the asphalt to generate compounds with higher stability and boiling point. These compounds are difficult to crack and volatilize during high-temperature construction of asphalt, thereby achieving the purpose of reducing the pungent odor of asphalt fume; at the same time, microencapsulating the odor-free active component can also effectively prevent it from having no time to react due to rapid volatilization at high temperature, thereby extending the action time of the odor-free active component and further improving its safety of use.

[0067] (3) The modified slow-release odor-free microcapsules added to the odor-free asphalt of the present invention are relatively small in size, and their outer layer is a polydopamine film that can exert an interaction force with the polar molecules in asphalt and has good compatibility with asphalt. Therefore, after being added to asphalt, the road performance of asphalt can be effectively prevented from being affected.

[0068] (4) The shell surface of the modified sustained-release odor-free microcapsules added to the odor-free asphalt of the present invention is modified with a large amount of copper ions through chelation. These copper ions can capture some relatively active sulfur-containing and nitrogen-containing compounds with pungent odors in the asphalt to form π-complexes, thereby preventing their high-temperature volatilization and further reducing the pungent odor of asphalt fume.

[0069] (5) The auxiliary deodorizer added to the deodorizing asphalt of the present invention can also undergo nucleophilic reaction with the compounds with pungent odor in the asphalt to generate compounds with higher stability and boiling point, thereby achieving the purpose of reducing the pungent odor of asphalt fume. In addition, the auxiliary deodorizer has a higher boiling point and can exert its maximum deodorizing effect faster than the modified slow-release deodorizing microcapsules. While ensuring safety and deodorizing effect, it makes up for the defect that the modified slow-release deodorizing microcapsules cannot take effect immediately after being added to asphalt. BRIEF DESCRIPTION OF THE DRAWINGS

[0070] Figure 1 This is a scanning electron micrograph of the modified sustained-release odorless microcapsules prepared in Example 1. DETAILED DESCRIPTION

[0071] To further illustrate the technical solution of the present invention, the present invention will be clearly and detailed described below in conjunction with embodiments.

[0072] The sustained-release modified microcapsules of the present invention were tested for morphology by scanning electron microscopy, with an acceleration voltage of 20 kV. Since the wall material of the microcapsules was not conductive, the samples were sprayed with gold before the test.

[0073] The sustained-release modified microcapsules of the present invention are tested for surface elements by an X-ray spectrometer to confirm that copper ions are successfully modified on the surface of the microcapsules.

[0074] The sulfide in the odorless asphalt flue gas of the present invention is tested according to the national standard GBT14678-1993 for the determination of hydrogen sulfide, methyl mercaptan, methyl sulfide and dimethyl disulfide in air quality by gas chromatography.

[0075] The base asphalt used in the following examples and comparative examples is Sinopec Donghai brand No. 70 Grade A asphalt.

[0076] Example 1

[0077] S1: Add nano-tourmaline powder with a diameter of 40 nm, dodecyl dimethyl benzyl ammonium chloride and formamide in a mass ratio of 2:1:30 into the first container, stir at 180°C and 400 rpm for 5 hours, then wash with ethanol for multiple times, and vacuum dry at -30°C for 5 hours to obtain modified nano-tourmaline powder for standby use;

[0078] S2: Add 3-hydroxy-2-butanone, leaf acetate, γ-octalactone, o-methoxy-p-methylbenzaldehyde, citral, 4-hydroxy-3-methylallylbenzene in equal mass ratios into the second container, mix, and stir at 400 rpm for 10 min at 50° C. to obtain a core material mixture;

[0079] S3: Add the modified nano-tourmaline powder and formamide obtained in step S1 to the reaction system of step S2, wherein the mass ratio of the core material mixture, the modified nano-tourmaline powder and formamide is 2:1:20, and continue to stir at 400 rpm at 50°C for 5 hours;

[0080] S4: adding tetraethyl orthosilicate to the reaction system of step S3, wherein the mass ratio of the core material mixture to tetraethyl orthosilicate is 1:1, and continuing to stir at 400 rpm at 50° C. for 5 hours to obtain a Pickering emulsion;

[0081] S5: Use a peristaltic pump to slowly add 10 wt % dilute hydrochloric acid to the reaction system of step S4 until the pH of the reaction system is 4, continue stirring at 400 rpm at 50° C. for 5 hours, then stop stirring, keep the temperature unchanged and age for 24 hours, then filter and wash the solid powder in the reaction system, and vacuum dry it at -30° C. for 5 hours;

[0082] S6: adding the solid powder obtained in step S5 to a Tris buffer solution with a pH value of 8.5, wherein the mass ratio of the Tris buffer solution to the solid powder is 50:1, then adding dopamine hydrochloride to make the concentration of dopamine in the reaction system 2 mg / mL, stirring the reaction at 200 rpm at 25°C for 12 hours, finally filtering and washing the bottom solid powder, and vacuum drying it at -30°C for 5 hours;

[0083] S7: Ultrasonic dispersion of the solid powder obtained in step S6 in a 50wt% anhydrous copper sulfate-formamide solution, the mass ratio of the solid powder to the anhydrous copper sulfate-formamide solution being 1:10, stirring and reacting at 400 rpm and 140°C for 2 hours, filtering and washing the bottom solid powder after the reaction, and vacuum drying at -30°C for 5 hours to obtain modified sustained-release odor-free microcapsules, the electron microscope image of which is shown in FIG. Figure 1 .

[0084] Auxiliary deodorizer N-phenylmaleimide, 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, and 3-(3,5-dimethyl-4-hydroxyphenyl)acrylic acid are mixed in equal mass ratios, dispersed in 1-hydroxyethyl-carboxymethyl-alkylimidazoline, stirred at 400 rpm for 1 hour at 25°C, and then the modified sustained-release deodorizing microcapsules prepared in step S7 are added, and stirring is continued for 1 hour to prepare the deodorizing asphalt additive. The mass ratio of the auxiliary deodorizer, the modified sustained-release deodorizing microcapsules, and 1-hydroxyethyl-carboxymethyl-alkylimidazoline is 1:1:2.

[0085] Heat the base asphalt to 143°C, add the above-mentioned odor-free asphalt additive at a rotation speed of 500 rpm, and stir for 2 hours to obtain the odor-free asphalt. The mass ratio of the odor-free asphalt additive to the base asphalt is 4:50.

[0086] Example 2

[0087] Except that in step S2, the core material mixture liquid is mixed with 2,3-butanedione, ethyl isovalerate, γ-valerolactone, phenylacetaldehyde, citronellal, and 4-propenylanisole in equal mass proportions, the rest is the same as in Example 1.

[0088] Example 3

[0089] When preparing the deodorizing asphalt additive, the mass ratio of the auxiliary deodorizing agent, the modified sustained-release deodorizing microcapsule, and 1-hydroxyethyl-carboxymethyl-alkyl imidazoline is 2:1:5, and the rest is the same as in Example 1.

[0090] Example 4

[0091] When preparing the deodorizing asphalt additive, the auxiliary deodorizing agent is a mixture of 6-(maleimido)hexanoic acid succinimide ester, 2,6-di-tert-butyl-p-methylphenol, and 3-(3,5-dimethoxy-4-hydroxyphenyl)acrylic acid in equal mass proportions, and the rest is the same as Example 1.

[0092] Example 5

[0093] Except that when preparing the odorless asphalt additive, the dispersant is dodecyl dimethyl betaine, and the remaining steps are the same as those in Example 1.

[0094] Example 6

[0095] Except that in step S3, the mass ratio of the core material mixed solution, the modified nano-tourmaline powder and formamide is 5:1:20, the remaining steps are the same as those in Example 1.

[0096] Example 7

[0097] Except that the mass ratio of the solid powder to the anhydrous copper sulfate-formamide solution in step S7 is 1:5, the remaining steps are the same as those in Example 1.

[0098] Comparative Example 1

[0099] S1: Add 3-hydroxy-2-butanone, leaf acetate, γ-octalactone, o-methoxy-p-methylbenzaldehyde, citral, 4-hydroxy-3-methylallylbenzene in equal mass ratios into a container, mix them, and stir them at 400 rpm for 10 minutes at 50° C. to obtain a core material mixture.

[0100] The auxiliary deodorant active components N-phenylmaleimide, 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, and 3-(3,5-dimethyl-4-hydroxyphenyl)acrylic acid are mixed in equal mass ratios, dispersed in 1-hydroxyethyl-carboxymethyl-alkylimidazoline, stirred at 400 rpm for 1 hour at 25°C, and then added with the core material mixture prepared in step S1, and stirred for 1 hour to prepare the deodorizing asphalt additive. The mass ratio of the auxiliary deodorant, the core material mixture, and 1-hydroxyethyl-carboxymethyl-alkylimidazoline is 1:1:2.

[0101] Heat the base asphalt to 143°C, add the odorless asphalt additive at a rotation speed of 500 rpm, and stir for 2 hours to obtain the odorless asphalt. The mass ratio of the odorless asphalt additive to the base asphalt is 4:50.

[0102] Comparative Example 2

[0103] The preparation of modified sustained-release odor-free microcapsules is the same as in Example 1.

[0104] After mixing the auxiliary deodorizer active components N-phenylmaleimide, 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, and 3-(3,5-dimethyl-4-hydroxyphenyl)acrylic acid in equal mass ratios, the modified sustained-release deodorizing microcapsules prepared by S8 are added to obtain the deodorizing asphalt additive. The mass ratio of the auxiliary deodorizer to the modified sustained-release deodorizing microcapsules is 1:1.

[0105] Heat the base asphalt to 143°C, add the odorless asphalt additive at a rotation speed of 500 rpm, and stir for 2 hours to obtain the odorless asphalt. The mass ratio of the odorless asphalt additive to the base asphalt is 4:50.

[0106] Comparative Example 3

[0107] Step S1 to step S6 are the same as in Example 1;

[0108] The auxiliary deodorant active components N-phenylmaleimide, 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, and 3-(3,5-dimethyl-4-hydroxyphenyl)acrylic acid are mixed in equal mass ratios, dispersed in 1-hydroxyethyl-carboxymethyl-alkylimidazoline, stirred at 400 rpm at 25°C for 1 hour, and then the solid powder prepared by S6 is added, and stirring is continued for 1 hour to obtain the deodorizing asphalt additive. The mass ratio of the auxiliary deodorant, the solid powder, and the 1-hydroxyethyl-carboxymethyl-alkylimidazoline is 1:1:2.

[0109] Heat the base asphalt to 143°C, add the odorless asphalt additive at a rotation speed of 500 rpm, and stir for 2 hours to obtain the odorless asphalt. The mass ratio of the odorless asphalt additive to the base asphalt is 4:50.

[0110] Comparative Example 4

[0111] S1: Add 3-hydroxy-2-butanone, leaf acetate, γ-octalactone, o-methoxy-p-methylbenzaldehyde, citral, 4-hydroxy-3-methylallylbenzene in equal mass ratios into a container, and stir at 400 rpm for 10 min at 50° C. to obtain a core material mixture;

[0112] S2: Add dodecyl dimethyl benzyl ammonium chloride and formamide to the reaction system of step S1, the mass ratio of the core material mixture, dodecyl dimethyl benzyl ammonium chloride and formamide is 2:1:20, and continue to stir at 400 rpm at 50°C for 5 hours;

[0113] S3: adding tetraethyl orthosilicate to the reaction system of step S2, with the mass ratio of the core material mixture to tetraethyl orthosilicate being 1:1, and continuing to stir at 400 rpm at 50° C. for 5 hours to obtain an emulsion;

[0114] S4: Use a peristaltic pump to slowly add 10 wt % dilute hydrochloric acid to the reaction system of step S3 until the pH of the reaction system is 4, continue stirring at 400 rpm at 50° C. for 5 hours, then stop stirring, keep the temperature unchanged and age for 24 hours, then filter and wash the solid powder in the reaction system, and vacuum dry it at -30° C. for 5 hours;

[0115] S5: adding the solid powder obtained in step S4 to a Tris buffer solution with a pH value of 8.5, wherein the mass ratio of the Tris buffer solution to the solid powder is 50:1, then adding dopamine hydrochloride to make the concentration of dopamine in the reaction system 2 mg / mL, stirring the reaction at 200 rpm at 25°C for 12 hours, finally filtering and washing the bottom solid powder, and vacuum drying it at -30°C for 5 hours;

[0116] S6: ultrasonically dispersing the solid powder obtained in step S5 in a 50wt% anhydrous copper sulfate-formamide solution, wherein the mass ratio of the solid powder to the anhydrous copper sulfate-formamide solution is 1:10, stirring and reacting at 400 rpm and 140°C for 2 hours, filtering and washing the bottom solid powder after the reaction is completed, and vacuum drying at -30°C for 5 hours to obtain modified sustained-release odor-free microcapsules;

[0117] Auxiliary deodorizer N-phenylmaleimide, 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, and 3-(3,5-dimethyl-4-hydroxyphenyl)acrylic acid are mixed in equal mass ratios, dispersed in 1-hydroxyethyl-carboxymethyl-alkylimidazoline, stirred at 400 rpm for 1 hour at 25°C, and then the modified sustained-release deodorizing microcapsules prepared in step S6 are added, and stirring is continued for 1 hour to prepare the deodorizing asphalt additive. The mass ratio of the auxiliary deodorizer, the modified sustained-release deodorizing microcapsules, and 1-hydroxyethyl-carboxymethyl-alkylimidazoline is 1:1:2.

[0118] Heat the base asphalt to 143°C, add the odorless asphalt additive at a rotation speed of 500 rpm, and stir for 2 hours to obtain the odorless asphalt. The mass ratio of the odorless asphalt additive to the base asphalt is 4:50.

[0119] Test Case

[0120] Sulfide is the main reason for the pungent smell of asphalt fume. Sinopec Donghai Brand No. 70 Grade A asphalt was used to prepare odorless asphalt. The asphalt prepared in the embodiment and the comparative example was stored at 143°C for 0 day, 7 days and 30 days. Then, an equal mass of the stored asphalt was transferred to a closed container, and the flue gas was enriched at a temperature of 163°C and a stirring speed of 300 rpm for 4 hours. After the enrichment, the gas in the closed container was aspirated, and the sulfide content in the gas was tested using gas chromatography. The data obtained are shown in Table 1 below.

[0121] Table 1 Gas chromatography sulfide test data

[0122]

[0123] It should be emphasized that the above-mentioned contents are only specific embodiments of the present invention, and it cannot be determined that the present invention is limited to the above description in the specific implementation process. For scientific research and technical personnel in the technical field to which the present invention belongs, any simple deduction and improvement made without departing from the ideas and principles of the present invention shall be deemed to be within the scope of protection of the present invention.

Claims

1. A odorless asphalt additive, characterized in that: The following components are included by weight: Auxiliary deodorant, 1-5 parts; Modified sustained-release odorless microcapsules, 1-5 parts; Dispersant, 1-10 parts; The modified sustained-release odor-free microcapsule comprises a shell material and a core material, wherein the shell material is a composite shell material comprising silica / nano-tourmaline / polydopamine, the core material comprises one or more of ketones, esters, aldehydes, and ethers, and the surface of the shell material is loaded with a metal chelate.

2. The odorless asphalt additive according to claim 1, characterized in that: The auxiliary deodorant is selected from one or more of maleamide compounds having more than 4 carbon atoms or antioxidants having more than 20 carbon atoms.

3. The odorless asphalt additive according to claim 2, characterized in that: The maleimide compound having a carbon number greater than 4 is selected from one or more of N-phenylmaleimide, 6-(maleimido)hexanoic acid succinimide ester, tris(2-maleimidoethyl)amine, and N-(2-hydroxyethyl)maleimide; And / or, the antioxidant having more than 20 carbon atoms is a hindered phenol antioxidant and / or an aromatic acid antioxidant having a boiling point greater than 300°C; the hindered phenol antioxidant having more than 20 carbon atoms is selected from one or more of 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, 2,6-di-tert-butyl-p-methylphenol, and 2,6-di-tert-butyl-p-methylphenol; the aromatic acid antioxidant having a boiling point greater than 300°C is selected from one or more of 3-(3,5-dimethyl-4-hydroxyphenyl)acrylic acid, 3-(3,5-dimethoxy-4-hydroxyphenyl)acrylic acid, and 3-(3-methoxy-4-hydroxyphenyl)acrylic acid.

4. The odorless asphalt additive according to claim 1, characterized in that: The dispersant is one or more of dodecyl dimethyl betaine and 1-hydroxyethyl-carboxymethyl-alkyl imidazoline.

5. The odorless asphalt additive according to claim 1, characterized in that: The particle size of the modified sustained-release odor-free microcapsule is 1-5 μm.

6. The odorless asphalt additive according to claim 1, characterized in that: The mass ratio of the shell material to the core material of the modified sustained-release odor-free microcapsule is 1:(0.5-2).

7. The odorless asphalt additive according to claim 1, characterized in that: The shell material of the modified sustained-release odor-free microcapsule is a composite shell material comprising silicon dioxide / nano-tourmaline / polydopamine, wherein the mass ratio of silicon dioxide to nano-tourmaline is (1-5):1, and the mass ratio of silicon dioxide to polydopamine shell material is 1:(0.1-0.5).

8. The odorless asphalt additive according to claim 1, characterized in that: The surface of the shell material of the modified sustained-release odor-free microcapsule is loaded with metal chelate, and the metal loading accounts for 0.1wt%-15wt% of the total mass of the modified sustained-release odor-free microcapsule.

9. The odorless asphalt additive according to claim 1, characterized in that: The ketones are aliphatic ketones having a carbon number greater than 4; the aliphatic ketones having a carbon number greater than 4 are selected from one or more of 3-hydroxy-2-butanone, 2,3-butanedione, and 3-pentene-2-one; And / or, the esters are selected from fatty acid esters having a carbon number greater than 5 and lactones having a carbon number greater than 5; the fatty acid esters having a carbon number greater than 5 are selected from one or more of butyl acetate, isoamyl acetate, leaf acetate, leaf isobutyrate, ethyl isovalerate, butyl caproate, ethyl laurate, and ethyl caprylate; the lactones having a carbon number greater than 5 are selected from one or more of γ-valerolactone, γ-caprolactone, γ-octanolactone, and γ-nonalactone; And / or, the aldehydes are selected from aromatic aldehydes having a carbon number greater than 6 and terpene aldehydes having a carbon number greater than 8; the aromatic aldehydes having a carbon number greater than 6 are selected from one or more of benzaldehyde, phenylacetaldehyde, o-methoxy-p-methylbenzaldehyde, and 2-methyl-3-(3,4-methylenedioxyphenyl)propanal; the terpene aldehydes having a carbon number greater than 8 are selected from one or more of citral, citronellal, and hydroxycitronellal; And / or, the ethers are aromatic ethers having a carbon number greater than 9; the aromatic ethers having a carbon number greater than 9 are selected from one or more of 4-hydroxy-3-methylallylbenzene and 4-propenylanisole.

10. The odorless asphalt additive according to claim 1, characterized in that: The preparation method of the modified sustained-release odor-free microcapsules comprises the following steps: S1: mixing nano tourmaline powder, a surfactant and a solvent, modifying the mixture under stirring, washing the mixture after modification, and freeze-drying the mixture to obtain modified nano tourmaline powder; S2: stirring and mixing one or more of ketones, esters, aldehydes, and ethers to obtain a core material mixed liquid; S3: adding the solvent and the modified nano-tourmaline powder obtained in step S1 to the core material mixed solution obtained in step S2, and stirring and mixing; S4: adding the shell material precursor to the reaction system in step S3, stirring and mixing, and obtaining a Pickering emulsion; S5: adjusting the pH value of the Pickering emulsion obtained in step S4 to 2-5, continuing stirring, then aging, filtering, and freeze-drying; S6: adding the solid powder obtained in step S5 to a buffer solution, adding dopamine hydrochloride, treating under stirring, and then filtering, washing, and freeze-drying; S7: adding the solid powder obtained in step S6 to the metal ion salt-formamide solution and treating under stirring. After the reaction is completed, filtering, washing and freeze-drying are performed to obtain the modified sustained-release odor-free microcapsules.

11. The odorless asphalt additive according to claim 10, characterized in that: Step S1: the surfactant is a cationic surfactant, preferably one or more of dodecyldimethylbenzylammonium chloride, hexadecyltrimethylammonium bromide, and octadecyltrimethylammonium chloride; the solvent is an aprotic solvent with a boiling point > 100°C, preferably one or more of formamide, N,N-dimethylformamide, dimethylacetamide, and dimethylphosphoramide; And / or, the mass ratio of the nano-tourmaline powder to the surfactant is (1-10):1, and the mass ratio of the solvent to the surfactant is (10-50):

1.

12. The odorless asphalt additive according to claim 10, characterized in that: In step S1, the stirring speed is 400-600 rpm; the modification temperature is 100-200° C., and the modification time is 4-10 hours; And / or, in step S2, the stirring speed is 400-600 rpm, the stirring temperature is 30-70° C., and the stirring time is 3-10 minutes; And / or, in step S3, the stirring speed is 400-600 rpm, the stirring temperature is 40-60° C., and the stirring time is 4-6 hours; And / or, in step S4, the stirring speed is 400-600 rpm, the stirring temperature is 40-60° C., and the stirring time is 4-6 hours; And / or, in step S5, the stirring speed is 400-600 rpm, the stirring temperature is 40-60° C., and the stirring time is 4-6 hours; And / or, in step S6, the stirring speed is 100-300 rpm, the stirring temperature is 20-30° C., and the stirring time is 12-24 h; And / or, in step S7, the stirring speed is 200-450 rpm, the stirring temperature is 100-180° C., and the stirring time is 2-5 hours.

13. The odorless asphalt additive according to claim 10, characterized in that: In step S3, the solvent is an aprotic solvent with a boiling point > 100°C, preferably one or more of formamide, N,N-dimethylformamide, dimethylacetamide, and dimethylphosphoramide.

14. The odorless asphalt additive according to claim 10, characterized in that: In step S4, the shell material precursor is a silicate compound, preferably one or more of methyl silicate, ethyl orthosilicate, tetraethyl orthosilicate, and butyl orthosilicate, and more preferably ethyl orthosilicate; And / or, the mass ratio of the core material mixed liquid to the shell material precursor is (0.5-2):

1.

15. The odorless asphalt additive according to claim 10, characterized in that: In step S6, the buffer is one or more of a phosphate buffer, a carbonate buffer, and a tris hydrochloride buffer, preferably a tris hydrochloride buffer; the pH value of the buffer is 8-10; And / or, the mass ratio of the buffer solution to the solid powder obtained in step S5 is (30-100):

1.

16. The odorless asphalt additive according to claim 10, characterized in that: In step S6, after adding dopamine hydrochloride, the mass concentration of dopamine in the reaction system is 2-8 mg / mL.

17. The odorless asphalt additive according to claim 10, characterized in that: In step S7, the metal ion salt is preferably a copper ion salt, and more preferably anhydrous copper sulfate; And / or, in the metal ion salt-formamide solution, the mass ratio of the metal ion salt to formamide is (0.5-1.5):1; And / or, the mass ratio of the metal ion salt-formamide solution to the solid powder obtained in step S7 is (5-20):

1.

18. A deodorized asphalt, characterized in that: The following components are included by weight: Base asphalt, 50-500 parts; 1-50 parts of the odorless asphalt additive according to any one of claims 1-17.

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