Plant multi-component extract and application thereof in improving ageing resistance of asphalt

Abstract

The invention relates to the technical field of asphalt modification, in particular to plant multi-component extraction and application of the plant multi-component extraction to improvement of the anti-aging performance of asphalt. The extraction method of the plant multi-component extract comprises the following steps: selecting a whole plant or organ tissues of the plant, cleaning with clear water, taking out, peeling to obtain peel, and pulping to obtain pulp; and adding a settling agent into the slurry, stirring, carrying out suction filtration to obtain filter residues, drying, and grinding to obtain the plant multi-component extract. The plant multi-component extract can be used for improving the anti-aging performance of asphalt. The plant multi-component extract modified asphalt is high in storage stability, the anti-aging performance of the asphalt can be obviously improved, meanwhile, the preparation method of the product is simple, convenient, efficient, low in cost, environmentally friendly and free of pollution, and obvious technical and economic benefits are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of asphalt modification, and in particular to a plant multi-component extraction and application thereof in improving the anti-aging performance of asphalt. Background Art

[0002] Asphalt concrete is an important component of road construction. The degradation of asphalt's own performance is an important factor restricting the development of asphalt concrete, a road paving material, and aging directly leads to the decline of asphalt performance. Aging refers to the phenomenon that asphalt is affected by thermal shock, ultraviolet light, oxygen erosion, infrared radiation, water, gravity load and other factors during hot mixing, storage, transportation, construction and use, resulting in component imbalance and irreversible chemical changes, and then a series of macro-mechanical performance degradation phenomena such as hardening and cracking. Aging asphalt concrete roads often have a large number of pits, cracks, looseness, subsidence, and congestion, which seriously affect the driving comfort experience, and at the same time cause a lot of economic losses and personal safety hazards. Improving the aging resistance of asphalt is an important means to improve the service performance of asphalt concrete and extend the durability of road pavement. It plays an important role in extending the service life of asphalt concrete, increasing the service life of asphalt concrete road pavement, and building long-life pavement.

[0003] There are two main methods to improve the thermal oxidative aging resistance of asphalt: physical and chemical. The physical method is to increase the viscosity of asphalt and extend the molecular motion trajectory to block the material exchange between asphalt and the atmosphere, which can effectively improve the tolerance of asphalt to heat and oxygen. However, the modifiers required by the physical method are mostly inorganic modifiers, such as montmorillonite, expanded vermiculite, hydrotalcite, etc., which have poor compatibility with asphalt and limited application prospects. The chemical method is to decompose or capture the peroxide free radicals and alkyl free radicals in the asphalt to terminate the chain reaction and inhibit the expansion of asphalt molecules, which can also achieve the purpose of anti-aging.

[0004] Organic antioxidants can react with free radicals on the asphalt molecular chain to terminate the chain growth of asphalt molecules and prevent the conversion of light components into heavy components. Therefore, they are often used to improve the anti-aging properties of asphalt. There are many types of antioxidants, including phenolic antioxidants, organic sulfur and phosphorus antioxidants, organic sulfur antioxidants, amine antioxidants, etc. Among them, phenolic antioxidants and amine antioxidants mainly improve the anti-aging properties of organic matter by capturing alkyl free radicals and peroxide free radicals. These two free radicals are the main products of asphalt aging process. Therefore, they are widely used to enhance the anti-aging properties of asphalt.

[0005] Phenols are highly efficient free radical scavengers with excellent performance in capturing free radicals generated by aging, but their cost is relatively high, with a market price of RMB 20,000-100,000 / ton. When the cost is calculated based on a 1% dosage of antioxidant-modified asphalt, the cost of antioxidant materials required for each ton of asphalt increases by RMB 200-1,000 / ton, while the value of asphalt is only RMB 2,000-4,000 / ton, which increases the economic burden. There is an urgent need for a lower-cost way to obtain phenolic antioxidants to reduce costs and increase efficiency.

[0006] Lignin and cellulose can significantly improve the high temperature stability and low temperature crack resistance of asphalt, reduce harmful gas emissions, are recyclable, have good storage stability, and are easy to construct and work. As a by-product of the papermaking industry, lignin is relatively cheap, about 5,000-8,000 yuan / ton. However, its collection, treatment and processing costs may affect its application cost in asphalt. In addition, the performance of lignin from different sources varies greatly, and screening and optimization are required. The price of cellulose is relatively high, especially high-quality cellulose fibers, with a market price of about 8,000-15,000 yuan / ton.

[0007] In response to the high material cost problem that occurs when phenols, lignin and cellulose are used in modified asphalt, the present invention provides a method for extracting plant multi-components for improving the anti-aging properties of asphalt. The preparation process of extracting plant multi-components can significantly reduce material costs, alleviate the economic burden, and comprehensively improve the anti-aging properties of asphalt. Summary of the invention

[0008] The purpose of the present invention is to provide a plant multi-component extraction and its application in improving the anti-aging performance of asphalt. The extraction method of the plant multi-component extract is simple and effective, with low raw material cost and low processing cost. The anti-aging performance of asphalt modified by the plant multi-component extract is significantly improved.

[0009] The invention provides a plant multi-component extract. The extraction method of the plant multi-component extract comprises: selecting a whole plant or plant organ tissue, washing it with clean water, taking it out, peeling it to obtain the peel, beating it to obtain a slurry; adding a sedimentation agent to the slurry and stirring it, and drying and grinding the obtained filter residue after suction filtration to obtain the plant multi-component extract.

[0010] Furthermore, the plant multi-component extract has the appearance of dark yellow powder, a polyphenol content of 5-10%, a pH value of 7-9, and an inorganic salt content of less than 1%.

[0011] Furthermore, the plant includes at least one of walnut, pomegranate, pomegranate peel, banana, and grape, and the growth period of the plant is in the growth period or the maturity period.

[0012] Furthermore, the walnut includes green walnut skin; the pomegranate includes pomegranate skin; the banana includes banana skin; and the grape includes grape seeds and grape skin.

[0013] Furthermore, the beating speed is 5000-30000 r / min, and the beating time is 2-10 min.

[0014] Furthermore, the sedimentation agent includes at least one of lime, polyaluminium chloride, ferric chloride, polyacrylamide and chitosan.

[0015] Furthermore, the lime concentration is 50-100 g / L, the polyaluminium chloride concentration is 20-60 g / L, the ferric chloride concentration is 10-30 g / L, the polyacrylamide concentration is 5-10 g / L, and the chitosan concentration is 5-20 g / L.

[0016] Furthermore, the stirring temperature is room temperature, the stirring speed is 50-1000 r / min, and sealing is performed during the stirring process.

[0017] Furthermore, the drying method comprises: placing the filter residue obtained after suction filtration in a vacuum drying oven, and drying for 11-13 hours at a temperature of 40-50° C. to obtain a dry filter residue.

[0018] Furthermore, the grinding method includes: grinding the dried filter residue at a rotation speed of 500-1500 r / min for 10-30 minutes.

[0019] On the other hand, the plant multi-component extracts in the present invention are used to improve the anti-aging properties of asphalt.

[0020] Furthermore, the method for improving the anti-aging performance of asphalt includes: pouring 70# base asphalt into a container, heating it to 135-145°C, adding plant multi-component extracts in batches, and high-speed shearing at a speed of 2000-6000r / min for 0.5-3h to obtain plant multi-component extract modified asphalt; the weight ratio of the base asphalt and the plant multi-component extract is 500: (15-40).

[0021] The beneficial effects of the present invention are: The present invention uses plants with high antioxidant content, and the cost of raw materials in plant-rich areas can be ignored; the cleaning and peeling processes only require a small amount of labor; the equipment required for pulping, filtering, drying and storage processes is simple and easy to operate. The entire preparation process does not produce any waste residue, which can be directly discharged in the open air, reducing the environmental load.

[0022] The present invention tests the anti-aging properties of asphalt modified with plant full-component extracts, and concludes that the residual needle penetration is increased by 15%-30% compared with 70# base asphalt; the softening point aging index is reduced by 2℃-2.5℃ compared with 70# base asphalt; the ductility aging index is increased by 30%-50%, the viscosity aging index is reduced by 5%-10%, and the storage stability is less than 0.2℃.

[0023] The plant full-component extract prepared in the present invention significantly improves the road performance and anti-aging performance of asphalt, and has the effect of inhibiting asphalt smoke. The product has high production efficiency and low cost, and has broad application prospects and value. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The Fourier transform infrared spectrum of the walnut green peel extract of the present invention. DETAILED DESCRIPTION

[0025] The technical solution of the present invention is described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] The invention provides a plant multi-component extract. The extraction method of the plant multi-component extract comprises: selecting a whole plant or plant organ tissue, washing it with clean water, taking it out, peeling it to obtain the peel, beating it to obtain a slurry, the beating speed is 5000-30000r / min, and the beating time is 2-10min; adding a sedimentation agent to the slurry and stirring it, the stirring temperature is room temperature, the stirring speed is 50-1000r / min, and sealing is performed during the stirring process; placing the filter residue obtained after suction filtration in a vacuum drying oven, drying it for 11-13h at a temperature of 40-50℃ to obtain a dried filter residue; grinding the dried filter residue at a rotation speed of 500-1500r / min for 10-30 minutes to obtain the plant multi-component extract; the plant multi-component extract has the appearance of a dark yellow powder, a polyphenol content of 5-10%, a pH value of 7-9, and an inorganic salt of less than 1%.

[0027] The plants include but are not limited to walnuts, green walnut peels, pomegranates, pomegranate peels, bananas, banana peels, grapes, grape seeds and grape peels, and the growth period of the plants is in the growth period or the maturity period; the sedimentation agents include but are not limited to lime, polyaluminium chloride, ferric chloride, polyacrylamide and chitosan; the lime concentration is 50-100g / L, the polyaluminium chloride concentration is 20-60g / L, the ferric chloride concentration is 10-30g / L, the polyacrylamide concentration is 5-10g / L, and the chitosan concentration is 5-20g / L.

[0028] It should be noted that the polyaluminium chloride in the present invention is powdery polyaluminium chloride with a degree of polymerization of 2-10.

[0029] The aforementioned plant multi-component extract is used to improve the anti-aging performance of asphalt. The method for improving the anti-aging performance of asphalt is to modify the asphalt using the aforementioned plant multi-component extract. The specific steps include: pouring 70# base asphalt into a container, heating it to 135-145°C, adding the plant multi-component extract in batches, and high-speed shearing at a speed of 2000-6000r / min for 0.5-3h to obtain plant multi-component extract modified asphalt; the weight ratio of the base asphalt and the plant multi-component extract is 500: (15-40).

[0030] The following is further explained with specific examples.

[0031] Example 1 The selected green walnuts come from Chuxiong City, Yunnan Province, and the picking season is the end of August. 20 kg of green walnuts are put into a cleaning machine, and 20 L of drinking water is injected for cleaning. The washed green walnuts are peeled to obtain walnut green skins. 1 kg of walnut green skins are put into a pulping machine, and the speed is set to 10,000 rpm for 7 minutes to obtain a slurry.

[0032] Take 500 mL of the slurry in a beaker, add 15 g of polyaluminium chloride, seal the container with a sealing film, stir with a magnetic stirrer at room temperature and a stirring rate of 500 rpm for 2 minutes, and let it stand for 10 minutes after the stirring is completed.

[0033] Slowly pour the upper liquid into the recovery bucket, filter the lower sediment to obtain filtrate and filter residue, put the filtrate into the recovery bucket, and keep the filter residue for later use.

[0034] The filter residue was placed in a vacuum drying oven at 45° C. for 12 hours to obtain a dry cake-like product.

[0035] The cake-like product was placed in a grinding machine and set to work at a speed of 1000 rpm for 10 minutes. The obtained powdered product was passed through a 200-mesh sieve to obtain a plant multi-component extract, which was placed in a sealed bag and evacuated to obtain a walnut green peel extract for later use. The technical parameters of the obtained walnut green peel extract are shown in Table 1 below: Table 1 Technical parameters of walnut green peel extract The main chemical composition of walnut peel extract is as follows Figure 1 As shown, its chemical characteristic peaks mainly include 3270cm -1 Hydroxyl, 1625cm -1 Vibration of benzene carbon skeleton, 1398 cm-1 The in-plane vibration of hydroxyl groups and 1081cm -1 The characteristic peaks of carbon-oxygen vibrations indicate that the main components of the extract are polymeric phenols, achieving the design goal.

[0036] Pour 500 grams of 70# base asphalt into a container, place the container on a hot plate, set the temperature to 140°C, and put it into a high-speed shearing machine.

[0037] After the temperature reaches 140°C, the high-speed shearing machine is started, the speed is set to 3000 rpm, and the machine is operated continuously for 2.5 hours. During this period, 21 grams of plant multi-component extract is divided into three equal parts and added to the asphalt at intervals of ten minutes.

[0038] 50 grams of plant multi-component extract modified asphalt was loaded into an aging tray and placed in a film aging test box for an aging test. After the aging operation was completed, the three major indicators, viscosity, and storage stability tests were conducted together with the unaged modified asphalt.

[0039] (1) The aging test is a film oven aging test, and the test steps are carried out in accordance with the requirements of T0608 in the national standard JTGE20-2011; (2) The three major indicators, viscosity and storage stability tests were carried out in accordance with the requirements of T0604, T0605, T0606, T0625 and T0655 in the national standard JTGE20-2011.

[0040] The results are shown in Table 2 below: Table 270# Performance indicators of base asphalt and walnut green peel multi-component extract modified asphalt Example 2 The selected bananas are grade 7 fully mature bananas from Honghe Prefecture, Yunnan Province. 10 kg of bananas are put into a washing machine, injected with 12 L of drinking water for washing, and the washed bananas are peeled to obtain banana peels. 1 kg of banana peels are put into a pulping machine, set at a speed of 7000 rpm and work for 3 minutes to obtain a slurry.

[0041] Take 500 mL of slurry in a beaker, add 500 mL of drinking water, then add 60 g of lime, seal the container with a sealing film, stir with a magnetic stirrer at room temperature and a stirring rate of 200 rpm for 3 minutes, and then let it stand for 30 minutes.

[0042] Slowly pour the upper liquid into the recovery bucket, filter the lower sediment to obtain filtrate and filter residue, put the filtrate into the recovery bucket, and keep the filter residue for later use.

[0043] The filter residue was placed in a vacuum drying oven at 55° C. for 10 hours to obtain a dry cake-like product.

[0044] The cake-like product is placed in a grinder and set to work at a speed of 800 rpm for 15 minutes. The obtained powder product is passed through a 200-mesh sieve to obtain a plant multi-component extract, which is placed in a sealed bag and evacuated for later use as a banana peel extract. The total polyphenol content in the banana peel extract is 120-180 mg / g (dry weight), the lignin content is 40-80 mg / g, and the cellulose content is 90-170 mg / g.

[0045] Pour 500 grams of 70# base asphalt into a container, place the container on a hot plate, set the temperature to 140°C, and put it into a high-speed shearing machine.

[0046] After the temperature reaches 140°C, start the high-speed shearing machine, set the speed to 4000 rpm, and continue working for 3 hours. During this period, 18 grams of plant multi-component extract was divided into 3 equal parts and added to the asphalt at intervals of ten minutes.

[0047] 50 grams of plant multi-component extract modified asphalt was put into an aging tray and placed in a film aging test box for aging test. After the aging operation was completed, the three major indicators, viscosity, and storage stability tests were conducted with the unaged modified asphalt. The results are shown in Table 3 below: Table 370# Performance indicators of base asphalt and banana peel multi-component extract modified asphalt Finally, it should be noted that the above embodiments are only used to illustrate the present invention and are not intended to limit the technical solutions described in the present invention. Those skilled in the art should understand that the present invention can still be modified or replaced by equivalents. All technical solutions and improvements that do not depart from the spirit and scope of the present invention should be included in the scope of the claims of the present invention.

Claims

1. A plant multi-component extract, characterized in that: The method for extracting the plant multi-component extract comprises: selecting a whole plant or plant organ tissue, washing it with clean water, taking it out, peeling the peel to obtain the peel, and beating it to obtain a slurry; adding a sedimentation agent to the slurry and stirring it, and drying and grinding the obtained residue after suction filtration to obtain the plant multi-component extract.

2. A plant multi-component extract according to claim 1, characterized in that: The plant comprises at least one of walnut, pomegranate, banana and grape, and the growth period of the plant is in the growth period or the maturity period.

3. A plant multi-component extract according to claim 1, characterized in that: The beating speed is 5000-30000 r / min, and the beating time is 2-10 min.

4. A plant multi-component extract according to claim 1, characterized in that: The sedimentation agent includes at least one of lime, polyaluminium chloride, ferric chloride, polyacrylamide and chitosan.

5. A plant multi-component extract according to claim 4, characterized in that: The lime concentration is 50-100 g / L, the polyaluminium chloride concentration is 20-60 g / L, the ferric chloride concentration is 10-30 g / L, the polyacrylamide concentration is 5-10 g / L, and the chitosan concentration is 5-20 g / L.

6. A plant multi-component extract according to claim 1, characterized in that: The stirring temperature is room temperature, the stirring speed is 50-1000 r / min, and sealing is performed during the stirring process.

7. A plant multi-component extract according to claim 1, characterized in that: The drying method comprises: placing the filter residue obtained after suction filtration in a vacuum drying oven, and drying for 11-13 hours at a temperature of 40-50° C. to obtain a dried filter residue.

8. A plant multi-component extract according to claim 1, characterized in that: The grinding method includes: grinding the dried filter residue at a rotation speed of 500-1500 r / min for 10-30 minutes.

9. Use of the plant multi-component extract as described in any one of claims 1 to 8 in improving the anti-aging properties of asphalt.

10. The use according to claim 9, characterized in that: The method for improving the anti-aging performance of asphalt comprises: pouring 70# base asphalt into a container, heating it to 135-145°C, adding plant multi-component extracts in batches, and high-speed shearing at a rotation speed of 2000-6000r / min for 0.5-3h to obtain plant multi-component extract modified asphalt; the weight ratio of the base asphalt to the plant multi-component extract is 500:(15-40).

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