Composite bioregenerated asphalt and method for its preparation

Abstract

The application discloses a kind of composite biological regeneration asphalt, composition is according to weight part: 66-85 portion of aged asphalt;2-6 portions of modified ZDC;5-20 portions of activated lignin;8 portions of bio-oil;The modified ZDC is zinc diethyl dithiocarbamate and is modified by silane coupling agent on surface;The activated lignin is lignin and is activated by glycerol;The composite biological regeneration asphalt obtained in the application is compounded by aged asphalt, modified zinc diethyl dithiocarbamate (ZDC), activated lignin and bio-oil according to weight part, ZDC realizes antioxidation by capturing free radicals, lignin relies on benzene ring structure to absorb ultraviolet light, and phenolic hydroxyl captures free radicals to realize the synergistic function of ultraviolet resistance-antioxidation, bio-oil supplements the light component lost by aged asphalt, reduces its penetration and softening point to realize regeneration regulation, and the synergistic effect of the three significantly improves the anti-aging performance and regeneration effect of composite asphalt.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of materials, and particularly relates to a composite bioregenerated asphalt and a preparation method thereof. BACKGROUND

[0002] With the surge in highway maintenance demand, recycling and utilization of waste asphalt pavement material (RAP) has become one of the core directions of green transportation development. The regenerated asphalt technology restores the road performance of aged asphalt by adding a regenerating agent, but the traditional regenerating agent (such as waste engine oil, diesel fraction) has the defect of poor anti-aging performance. During outdoor service, affected by factors such as ultraviolet radiation, oxygen, and temperature fluctuations, the regenerated asphalt is prone to re-oxidation of components and volatilization of light components, resulting in a decrease in penetration, an increase in softening point, and a decrease in ductility, ultimately causing pavement cracking, rutting, and other diseases, and shortening the service life of the pavement.

[0003] Existing research shows that the core mechanisms of performance degradation of regenerated asphalt include: 1. Oxidation: saturated components and aromatic components in asphalt are oxidized into resin and asphaltene, resulting in hardening and brittleness due to a large increase in molecular weight; 2. Ultraviolet aging: 280-400 nm ultraviolet light accelerates the breaking of asphalt molecular chains, generating polar groups such as carbonyl and sulfoxide groups, and aggravating the peeling of aggregate and asphalt; 3. Single function of regenerating agent: traditional regenerating agents can only "temporarily soften" aged asphalt and cannot inhibit the subsequent aging process, and have poor synergistic compatibility with anti-aging agents.

[0004] Currently, the industry has attempted to introduce anti-aging agents to improve the performance of regenerated asphalt: such as adding inorganic zinc-based nanomaterials (zinc-based antioxidants) alone, which can capture oxidation free radicals, but cannot resist ultraviolet radiation; adding lignin (biomass anti-ultraviolet agent) alone, which can absorb ultraviolet light, but has low antioxidant efficiency; and both of them are directly mixed into asphalt and are prone to agglomeration due to differences in surface energy, with a dispersion uniformity of ≤70%, making it difficult to play a synergistic role. At the same time, although bio-oil can achieve regeneration regulation by supplementing light components, it is easily oxidized and has not been optimized for compatibility with anti-aging agents, limiting its application in high-performance regenerated asphalt.

[0005] Therefore, there is an urgent need to develop a composite regenerated asphalt system with the triple functions of "regeneration regulation-anti-ultraviolet-anti-oxidation". SUMMARY

[0006] In order to solve the above technical problems, the present application aims to provide a kind of composite biological regenerated asphalt, which is compounded by aging asphalt, modified zinc diethyl dithiocarbamate (ZDC), activated lignin and bio-oil according to weight parts, ZDC realizes antioxidation by capturing free radicals, lignin relies on benzene ring structure to absorb ultraviolet light, and phenolic hydroxyl group captures free radicals to realize the synergistic function of ultraviolet resistance and antioxidation, bio-oil reduces its penetration and softening point by supplementing the light components lost by aging asphalt to realize regeneration regulation, and the synergistic effect of the three significantly improves the anti-aging performance and regeneration effect of composite asphalt.

[0007] In order to achieve the above-mentioned purpose, the technical scheme is as follows:

[0008] A kind of composite biological regenerated asphalt, composition is according to weight parts: aging asphalt 66-85 parts;Modified ZDC 2-6 parts;Activated lignin 5-20 parts;Bio-oil 8 parts;

[0009] The modified ZDC is zinc diethyl dithiocarbamate modified by silane coupling agent on the surface;

[0010] The activated lignin is lignin activated by glycerol.

[0011] According to the above scheme, the preparation method of the modified ZDC includes the following steps:

[0012] ZDC and KH560 are mixed according to the mass ratio of 100: (1-3), dispersed in an organic solvent, heated to 60-80 DEG C and stirred for 1-2 h, and then dried to obtain modified ZDC. By using "solvent assisted low temperature modification", a coating layer is formed on the surface of ZDC through the weak interaction between the silicon hydroxyl group of KH560 and the surface of ZDC, which solves the problem of interface compatibility between organic zinc and asphalt, and avoids the decomposition of ZDC (its melting point is about 171 DEG C) caused by high temperature. The dispersion uniformity of the obtained modified ZDC in asphalt is ≥95%, and the diameter of the agglomerated particles observed by optical microscope is ≤2 μm.

[0013] According to the above scheme, the preparation method of the activated lignin includes the following steps:

[0014] 5-8% glycerol is added to dry lignin, and the lignin is activated at 150-160 DEG C for 30-40 min to obtain activated lignin. The surface of lignin has strong polarity, and it is easy to agglomerate due to poor compatibility with asphalt. At 150-160 DEG C, hydrogen bonds or mild etherification reaction is formed between the hydroxyl group of glycerol molecule and the hydroxyl group on the surface of lignin, which introduces lipophilic-polar transition groups to reduce the surface polarity of lignin and reduce the polarity difference with asphalt. Finally, the activated lignin is uniformly dispersed in asphalt, effectively solving the compatibility and agglomeration problems, and glycerol can enhance the interfacial bonding force with asphalt to ensure the anti-aging performance.

[0015] According to the above scheme, the bio-oil is sunflower seed oil, the density is 0.9 g / mL, and the flash point is > 110 DEG C.

[0016] According to the above scheme, the composite bio-regenerated asphalt has a penetration (0.1 mm) of 60-100 at 25 DEG C, a ductility of > 50 cm at 15 DEG C, a penetration ratio of > 50% after rotary film oven aging (163 DEG C, 5 h), a mass loss of < 0.8%, and a residual ductility of > 20 cm.

[0017] The application also provides a preparation method of the composite bio-regenerated asphalt, which solves the problems of aging agent agglomeration and poor compatibility with asphalt by means of a "ZDC pre-dispersion-lignin activation-stepwise mixing-constant temperature development" process.

[0018] The preparation method of the composite bio-regenerated asphalt comprises the following steps:

[0019] (1) mixing modified ZDC and part of bio-oil, heating and shearing to disperse, to obtain a ZDC-bio-oil dispersion;

[0020] (2) heating and softening aging asphalt, adding the remaining bio-oil to shear and disperse to obtain an aging asphalt-bio-oil mixed system;

[0021] sequentially adding the ZDC-bio-oil dispersion and activated lignin to shear and disperse to obtain a composite asphalt mixture;

[0022] (3) developing the obtained composite asphalt mixture at a constant temperature, and naturally cooling to obtain the composite bio-regenerated asphalt.

[0023] According to the above scheme, the modified ZDC and the bio-oil are mixed at a mass ratio of 1:1 in step (1).

[0024] According to the above scheme, the heating and shearing to disperse in step (1) comprises shearing at 110-120 DEG C and 2000-3000 r / min for 8-12 min.

[0025] According to the above scheme, the ZDC-bio-oil dispersion obtained in step (1) has a D50 of < 3 µm.

[0026] According to the above scheme, the aging asphalt is heated to 160-180 DEG C and softened for 30-40 min in step (2).

[0027] According to the above scheme, the aging asphalt-bio-oil mixed system is obtained by shearing at 160-170 DEG C and 2000-3000 r / min for 15-20 min in step (2).

[0028] According to the above scheme, the ZDC-bio-oil dispersion and the activated lignin are added with an interval of 5-10 min in step (2).

[0029] According to the above scheme, step (2) is carried out at 170-180℃, 4000-6000r / min high-speed shearing for 20-40min to obtain the composite asphalt mixture.

[0030] According to the above scheme, the constant temperature development in step (3) includes stirring at 165-175℃, 500-800r / min for 15-25min.

[0031] Compared with the prior art, the present application has the following advantages:

[0032] (1) ZDC is an organic zinc product with purity ≥97.5%, in the form of powder or crystal, and a melting point of 171℃. The dithiocarbamate group (-S-C(=S)-NR2) in its molecular structure can capture ROO , HO and other free radicals generated by oxidation of asphalt through the lone pair of electrons of sulfur atom, and terminate the oxidative chain reaction; after modification by KH560, epoxy propoxy groups are introduced onto the surface, forming van der Waals force with the aromatic components of asphalt, and the dispersion uniformity is improved to more than 95%. The benzene ring structure of lignin absorbs ultraviolet light of 280-400nm (absorption rate ≥85%), and the phenolic hydroxyl group helps to scavenge free radicals; after activation by glycerol, the lipophilicity is improved, and a weak coordination bond is formed between the sulfur atom of ZDC, enhancing the synergistic anti-aging effect. Sunflower oil can supplement the light components lost by aged asphalt, and at the same time act as a dispersion medium for ZDC, dissolving organic zinc salts to avoid agglomeration, realizing the dual functions of "regeneration-dispersion". The three components synergistically prolong the anti-aging life of the composite asphalt.

[0033] (2) The regenerated asphalt prepared by compounding aged asphalt, antioxidant ZDC, lignin and bio-oil in a certain weight ratio, in which the antioxidant function of ZDC and the ultraviolet-oxidation resistance function of lignin are complementary, has higher aging penetration retention rate and aging ductility retention rate compared with ZDC or lignin alone, and the anti-aging efficiency is improved.

[0034] (3) Bio-oil not only adjusts the penetration and softening point of aged asphalt, but also helps to disperse ZDC and lignin, solving the problem of "regeneration agent only softening, not anti-aging", and prolonging the service life of the composite asphalt compared with ordinary regenerated asphalt.

[0035] (4) Lignin (derived from agricultural and forestry waste) and bio-oil are biomass raw materials, replacing part of the petroleum-based anti-aging agent, reducing production cost by 15-20%, and reducing pollution caused by burning of agricultural and forestry waste, in line with the "double carbon" goal.

[0036] (5) The preparation process uses conventional asphalt processing equipment (high-speed shearing machine, etc.), without the need for special equipment modification, and the steps of ZDC pre-dispersion and lignin activation are easy to implement on a large scale, suitable for industrial production. DETAILED DESCRIPTION

[0037] The following examples further illustrate the technical solutions of the present application, but are not intended to limit the scope of protection of the present application.

[0038] The specific embodiment provides a composite biological reclaimed asphalt, and the components are as follows in parts by weight: 66-85 parts of aged asphalt; 2-6 parts of modified ZDC; 5-20 parts of activated lignin; and 8 parts of biological oil; the modified ZDC is obtained by surface modification of zinc diethyl dithiocarbamate with a silane coupling agent; and the activated lignin is obtained by activation of lignin with glycerol.

[0039] Zinc diethyl dithiocarbamate (ZDC) is a mature organic zinc product, which has the advantages of high free radical scavenging rate, low cost, and good compatibility with organic systems, but has not been applied in the field of asphalt recycling. In the present application, the dispersibility of ZDC is optimized by modification with KH560, and the synergistic anti-aging mechanism of ZDC and lignin is combined with the regeneration and dispersion auxiliary effect of biological oil to solve the pain points of traditional reclaimed asphalt, i.e., "reclaimed asphalt is not resistant to aging, and anti-aging is difficult to disperse", and fill the application gap of organic zinc salt in asphalt recycling, thereby providing a technical solution for the recycling and utilization of waste asphalt in harsh environments.

[0040] The zinc diethyl dithiocarbamate used in the specific embodiment is an organic zinc product with a purity of ≥97.5%, in the form of powder or crystal, and a melting point of 171℃. The dithiocarbamate group (-S-C(=S)-NR2) in the molecular structure of the zinc diethyl dithiocarbamate can capture ROO , HO , and other free radicals generated by oxidation of asphalt through the lone pair of electrons of sulfur atom, thereby terminating the oxidative chain reaction. After modification with KH560, epoxypropoxy groups are introduced onto the surface, and Van der Waals forces are formed with aromatic components in asphalt, so that the dispersion uniformity is improved to more than 95%. The benzene ring structure of lignin absorbs ultraviolet light with a wavelength of 280-400 nm (absorption rate ≥85%), and the phenolic hydroxyl group assists in scavenging free radicals; after activation with glycerol, the lipophilicity is improved, and a weak coordination bond is formed between the sulfur atom of ZDC, thereby enhancing the synergistic anti-aging effect. The use of sunflower oil as biological oil can supplement the light components lost by aged asphalt, and at the same time, the sunflower oil acts as a dispersion medium for ZDC, dissolves the organic zinc salt to avoid agglomeration, and realizes the dual functions of "reclamation-dispersion". The synergistic effect of the three components prolongs the anti-aging life of the composite asphalt.

[0041] The specific embodiment further provides a preparation method of the composite biological reclaimed asphalt.

[0042] Step 1: ZDC modification and pre-dispersion. The modified ZDC and the biological oil are mixed at a mass ratio of 1:1, and are subjected to high-speed shearing at 110-120℃ and 2000-3000r / min for 8-12min to obtain a ZDC-biological oil dispersion (D50≤3μm).

[0043] Step 2: Step-by-step mixing. Heat the aged asphalt to 160-180℃, soften for 30-40 min, add the remaining bio-oil (total bio-oil minus the amount used in step 1), stir at 160-170℃, 2000-3000 r / min for 15-20 min to obtain an aged asphalt-bio-oil mixing system; add the ZDC-bio-oil dispersion and activated lignin to the mixing system in sequence (with an interval of 5-10 min), and high-speed shear at 170-180℃, 4000-6000 r / min for 20-40 min. In step-by-step mixing, bio-oil is added first to soften the aged asphalt, and then ZDC dispersion and activated lignin are added in sequence to ensure layer-by-layer dispersion of each component and avoid stratification due to density difference.

[0044] Step 3: Constant temperature development. Maintain the sheared mixture at 165-175℃, 500-800 r / min low-speed stirring for 15-25 min, and naturally cool to room temperature to obtain the composite bio-regenerated asphalt.

[0045] The specific embodiment provides a modified ZDC for the following specific embodiment:

[0046] Mix ZDC and KH560 at a mass ratio of 100:2, disperse in an organic solvent, heat to 60-80℃, stir for 1-2 h, and dry to obtain modified ZDC.

[0047] The specific embodiment provides an activated lignin for the following specific embodiment:

[0048] Lignin (CAS No. 8061-51-6) is purchased from Shandong Sya Chemical Co., Ltd., with a specification of analytical pure AR and an appearance of dark yellow or brown solid. Dry the lignin at 105℃ for 2.5 h, add 6% glycerol to the dried lignin, and stir at 150-160℃ for 30-40 min to obtain activated lignin.

[0049] The bio-oil used in the following specific embodiment is sunflower oil with a density of 0.9 g / mL and a flash point > 110℃.

[0050] Example 1

[0051] This embodiment provides a ZDC / lignin composite bio-regenerated asphalt. The ratio is 85 parts of aged asphalt, 2 parts of modified ZDC, 5 parts of activated lignin, and 8 parts of bio-oil by weight. The aged asphalt is obtained by long-term aging of base asphalt, and the base asphalt is road 90# asphalt.

[0052] Based on the raw material formula of this embodiment, the specific preparation process of the ZDC / lignin composite bio-regenerated asphalt of this embodiment is as follows:

[0053] Step 1: Mix the modified ZDC with an equal weight of bio-oil, and shear at 125℃ and 3500r / min for 12min to obtain a ZDC-bio-oil dispersion (D50=180nm).

[0054] Step 2: Keep aged asphalt at 170℃ for 35 minutes, add the remaining bio-oil and stir at 165℃ and 2500r / min for 18 minutes; add ZDC-bio-oil dispersion (5 minutes apart) and activated lignin in sequence, and shear at 175℃ and 5000r / min for 30 minutes.

[0055] Step 3: Maintain a constant temperature of 170℃, stir at 700r / min for 20min, and cool to room temperature.

[0056] According to JTGE20-2011 "Test Procedures for Asphalt and Asphalt Mixtures in Highway Engineering", aged asphalt and recycled asphalt were tested for three major indicators, rotational viscosity at 135℃, and rotational film heating test.

[0057] Comparative Example 1

[0058] This comparative example provides a ZDC composite bio-regenerated asphalt, whose proportions by weight are 90 parts aged asphalt, 2 parts modified ZDC, and 8 parts bio-oil. The specific preparation process of the ZDC composite bio-regenerated asphalt in this example is basically the same as that in Example 1.

[0059] Example 2

[0060] This embodiment provides a ZDC / lignin composite bio-regenerated asphalt. Its composition, by weight, is 83 parts aged asphalt, 4 parts modified ZDC, 5 parts activated lignin, and 8 parts bio-oil. The aged asphalt is obtained by long-term aging of the base asphalt, which is road-grade 90# asphalt. The specific preparation process of the ZDC / lignin composite bio-regenerated asphalt in this embodiment is basically the same as in Example 1.

[0061] Comparative Example 2

[0062] This comparative example presents a ZDC composite bio-regenerated asphalt. Its composition, by weight, is 88 parts aged asphalt, 4 parts modified ZDC, and 8 parts activated bio-oil. The specific preparation process of the ZDC composite bio-regenerated asphalt in this example is basically the same as in Example 1.

[0063] Example 3

[0064] This embodiment provides a ZDC / lignin composite bio-regenerated asphalt. Its composition, by weight, is 80 parts aged asphalt, 2 parts modified ZDC, 10 parts activated lignin, and 8 parts bio-oil. The specific preparation process of the ZDC / lignin composite bio-regenerated asphalt in this embodiment is basically the same as in Example 1.

[0065] Comparative Example 3

[0066] This comparative example provides a lignin-based bio-regenerated bitumen. Its composition, by weight, is 87 parts aged bitumen, 5 parts activated lignin, and 8 parts bio-oil. The specific preparation process of the lignin-based bio-regenerated bitumen in this example is basically the same as in Example 1.

[0067] Example 4

[0068] This embodiment provides a ZDC / lignin composite bio-regenerated asphalt. Its composition, by weight, is 78 parts aged asphalt, 4 parts modified ZDC, 10 parts activated lignin, and 8 parts bio-oil. The specific preparation process of the ZDC / lignin composite bio-regenerated asphalt in this embodiment is basically the same as in Example 1.

[0069] Comparative Example 4

[0070] This comparative example provides a lignin-based bio-regenerated bitumen. Its composition, by weight, is 82 parts aged bitumen, 10 parts activated lignin, and 8 parts bio-oil. The specific preparation process of the lignin-based bio-regenerated bitumen in this example is basically the same as in Example 1.

[0071] Comparative Example 5

[0072] Repeat Example 1, but replace the modified ZDC with an equal part by weight of ZDC, while keeping the rest unchanged.

[0073] Comparative Example 6

[0074] Repeat Example 1, but replace the activated lignin with an equal part by weight of lignin, while keeping the rest unchanged.

[0075] The performance test results of the recycled asphalt obtained in the above embodiments and comparative examples are shown in Table 1.

[0076] Table 1

[0077]

[0078] As shown in Table 1, all embodiments meet the requirements of JTGF40-2004 specification and 25°C penetration of 60-100 (0.1mm) and 15°C elongation ≥20cm, and exhibit a better performance balance than the comparative example.

[0079] Example 1 achieved a ductility of 80-88 cm at 15°C, significantly better than Comparative Example 3 (60 cm) and Comparative Example 4 (55 cm) without ZDC (lignin alone is prone to embrittlement), and also higher than Comparative Example 1 (70 cm) and Comparative Example 2 (75 cm) without lignin, demonstrating the synergistic effect described in the patent; the softening point of Example 1 was 48-51°C, higher than that of the comparative examples (45-48°C), indicating that ZDC and lignin effectively improve high-temperature stability; simultaneously, the viscosity of all samples at 135°C was 1.6-2.3 mm. 2 / s, all satisfying "≤3mm" 2 The " / s" specification requires that the patented "ZDC pre-dispersion + lignin activation" process can avoid viscosity abnormalities caused by regenerator agglomeration and is compatible with conventional asphalt construction equipment.

[0080] The mass loss after TFOT in the examples was 0.38-0.45%, lower than that in the comparative example (0.48-0.55%). This is because ZDC captures asphalt oxidation free radicals and lignin blocks ultraviolet light, synergistically inhibiting the oxidation and volatilization of lightweight components, which meets the patented anti-aging mechanism of "terminating the oxidation chain reaction". The residual ductility of the examples was 52-62 cm and the residual penetration ratio was 76-80%, which not only far exceeded the standard requirement of "residual ductility ≥20 cm and residual penetration ratio ≥50%", but also significantly improved compared with the comparative example (residual ductility 30-46 cm and residual penetration ratio 65-72%). Among them, Example 2 (ZDC 4wt% + lignin 5wt%) had a residual ductility of 62 cm and a residual penetration ratio of 80%, reaching the optimal level of "penetration retention rate ≥75% and ductility retention rate ≥65% after TFOT", confirming the patent conclusion that "ZDC's antioxidant effect and lignin's UV protection work synergistically, and the anti-aging efficiency is better than that of a single anti-aging agent". The composite bio-recycled asphalt with anti-aging properties described in the patent can achieve dual compliance with road performance and anti-aging performance standards. Its penetration at 25℃, ductility at 15℃, softening point, and viscosity at 135℃ all meet engineering specifications. Moreover, the residual performance retention rate of TFOT after aging is significantly higher than that of a single anti-aging agent system, effectively solving the pain points of traditional recycled asphalt that are "not anti-aging after recycling and difficult to disperse after anti-aging".

[0081] In Comparative Example 5, the unmodified ZDC, lacking epoxy propoxy groups, could not form van der Waals forces with the asphalt aromatics, resulting in reduced dispersion uniformity. This led to a decrease in penetration to 70 (0.1 mm) at 25°C, a decrease in ductility to 72 cm at 15°C, and an increase in viscosity to 2.5 mm at 135°C. 2 / s, and unable to form weak coordination bonds with activated lignin, the residual penetration ratio decreased to 70% after TFOT, indicating that KH560 modification can ensure dispersibility and antioxidant properties, achieving a synergistic effect. In Comparative Example 6, the unactivated lignin had poor lipophilicity and low phenolic hydroxyl utilization, causing the ductility at 15℃ to decrease to 78cm, and the residual ductility after TFOT decreased to 50cm, proving that glycerol activation plays an important role in improving compatibility and anti-aging synergy. Comparative Examples 5 and 6 show that by modifying ZDC, activating lignin, and combining the regeneration regulation and auxiliary dispersion functions of bio-oil, the pain points of traditional recycled asphalt, "regenerated asphalt is not anti-aging, and anti-aging is difficult to disperse," are effectively solved, fully demonstrating the scientific nature of the patented technology principle. The synergistic effect of ZDC, lignin, and bio-oil is the core of the performance advantage. After ZDC is modified with KH560, the dispersion uniformity is improved, and after glycerol activation, the lipophilicity of lignin is improved. The two form weak coordination bonds to enhance the anti-aging effect, while bio-oil balances the regeneration and dispersion requirements. This is completely consistent with the patented "triple functional synergy" technical principle.

[0082] The preparation of composite bio-regenerated asphalt relies on conventional high-speed shearing equipment without special modifications. Furthermore, lignin and bio-oil (sunflower seed oil) are biomass raw materials, which reduces costs compared to traditional petroleum-based anti-aging agents while meeting the "dual carbon" target. Combined with its excellent anti-aging properties (extended service life compared to ordinary recycled asphalt), it has the potential for large-scale application in high-temperature / high-altitude / open-air road scenarios with strong ultraviolet radiation and harsh oxidation environments.

Claims

1. A composite bio-regenerated asphalt, characterized in that... Composition by weight: 66-85 parts aged asphalt; 2-6 parts modified ZDC; 5-20 parts activated lignin; 8 parts bio-oil; The modified ZDC is obtained by surface modification of zinc diethyldithiocarbamate with a silane coupling agent; The method for preparing the activated lignin includes the following steps: Add 5-8 wt% glycerol to dry lignin and stir at 150-160℃ for 30-40 min to activate it and obtain activated lignin. The bio-oil is sunflower seed oil.

2. The composite bio-regenerated asphalt as described in claim 1, characterized in that... The preparation method of the modified ZDC includes the following steps: ZDC and KH560 were mixed at a mass ratio of 100:(1-3), dispersed in an organic solvent, heated to 60-80℃ and stirred for 1-2 hours, and then dried to obtain modified ZDC.

3. The composite bio-regenerated asphalt as described in claim 1, characterized in that... The sunflower seed oil has a density of 0.9 g / mL and a flash point >110℃.

4. The method for preparing the composite bio-regenerated asphalt according to claim 1, characterized in that... Includes the following steps: (1) The modified ZDC was mixed with a portion of bio-oil and heated to disperse by shearing to obtain a ZDC-bio-oil dispersion; (2) The aged asphalt was heated and softened, and the remaining bio-oil was added and sheared and dispersed to obtain an aged asphalt-bio-oil mixture system; The ZDC-bio-oil dispersion and activated lignin shear dispersion were added sequentially to obtain a composite asphalt mixture; (3) The resulting composite asphalt mixture is developed at a constant temperature and then naturally cooled to obtain composite bio-regenerated asphalt.

5. The method for preparing composite bio-regenerated asphalt as described in claim 4, characterized in that... In step (1), the modified ZDC and bio-oil are mixed at a mass ratio of 1:

1.

6. The method for preparing composite bio-regenerated asphalt as described in claim 4, characterized in that... The heating and shearing dispersion in step (1) includes shearing dispersion at 110-120℃ and 2000-3000r / min for 8-12min to obtain ZDC-bio-oil dispersion.

7. The method for preparing composite bio-regenerated asphalt as described in claim 4, characterized in that... Step (2) Shear dispersion at 160-170℃ and 2000-3000r / min for 15-20min to obtain aged asphalt-bio-oil mixture system.

8. The method for preparing composite bio-regenerated asphalt as described in claim 4, characterized in that... Step (2) Obtain the composite asphalt mixture by high-speed shearing at 170-180℃ and 4000-6000r / min for 20-40min.

9. The method for preparing composite bio-regenerated asphalt as described in claim 4, characterized in that... The isothermal development in step (3) includes stirring at 165-175℃ and 500-800r / min for 15-25min.

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