Catalytic Cracking Of Acid Zeolite To Prepare Waxy Asphalt Warming Agent

In recent years,the technology of warm mix asphalt mixture has developed rapidly.While ensuring the performance of asphalt and asphalt mixture,warm mix can reduce the temperature of mixing and paving,and effectively reduce the emission of harmful gases.Wax asphalt warm mixes,such as Sasobit,are widely used in road construction in China.However,most of the warm mixes currently used are imported and the prices are relatively expensive,resulting in high road construction costs.Waste plastics account for a relatively large proportion of industrial and domestic solid waste,which has caused tremendous pressure on environmental protection.The resource utilization technology can convert waste plastics into high value-added products such as fuel oil and wax,which can effectively alleviate the pollution of white garbage.Since wax can be used as an asphalt viscosity reducer,it is obviously feasible to prepare asphalt warm mix by cracking waste plastics,but the related research is still very limited.In this paper,from the perspective of reducing white pollution and resource reuse,polypropylene waste plastic cracking wax(PPW)was prepared by catalytic cracking,the modification performance of cracking wax on asphalt was studied,and cracking wax was evaluated as a warming agent Possibility.The main research contents are as follows:(1)Using polypropylene waste plastic as raw material,under the catalysis of modified zeolite,prepare waste polypropylene cracking wax(PPW).PPW yield,drop melting point and infrared spectroscopy analysis showed that the yield of PPW was higher at 0.8% catalyst dosage,and the melting point of PPW produced at the four cracking temperatures was lower than that of hot asphalt,from the perspective of wax It is preliminarily concluded that PPW has the capability of warm mixing.(2)In this paper,a single factor experiment is used to determine that the optimal dosage is 0.8% through a comparison experiment with different catalyst dosages and wax dosages.Carry out basic index tests such as penetration,softening point,ductility,penetration index and viscosity,and dynamic mechanical tests on modified asphalts with different wax contents,and analyze the temperature of waste polypropylene cracked wax modified asphalt from the verification of asphalt performance Mixing performance.By comparing the performance of the modified asphalt before and after adding the catalyst,the benign effect of the catalyst on the catalytic cracking of PP was determined.Through the performance indexes of different cracking temperatures,390 ℃ was determined as the optimal cracking temperature,and the conclusion that the cracking temperature of PP plastic particles should not exceed 400 ℃ was obtained.Viscosity is an important indicator of warm-mixed asphalt.The viscosity data of PPW modifiers produced at different temperatures after being mixed with asphalt are analyzed,and it is concluded that the modifier used in this research has excellent warm-mixing effect.The viscosity-reducing effect reached 30% at 135 ℃.(3)Through the initial road usability analysis of the modified asphalt film oven aging test,storage stability test and adhesion test,the storage stability,adhesion and anti-aging properties of the modified asphalt are determined.According to the calculation method of surface energy and adhesion work,the adhesion analysis of modified asphalt with different waste polypropylene cracking wax content was carried out,combined with the asphalt-aggregate’s resistance to water damage and exfoliation,and finally the best modifier was obtained.The dosage is 10%.(4)The road practicability test of the mixture is carried out with the optimal catalyst dosage of 0.8%,the optimal waste plastic cracking temperature of 390 ℃ and the optimal modifier dosage of 10%.Through the stability test,rutting test,freeze-thaw splitting test and porosity of the modified asphalt mixture,the mainstream road performance test was used to evaluate the application effect of the waste polypropylene cracked wax modified asphalt in actual engineering.And compared with the performance of Sasobit asphalt warm mix,economic analysis,according to the evaluation results to determine the practicability and use direction of waste polypropylene cracking wax modified asphalt.