Study On The Inhibition Effect Of Photocatalytic Materials On Road Asphalt Fume

Road asphalt will release a lot of harmful fume during mixing,paving and service,which will pollute the environment and cause harm to human health.With the extension of asphalt service time,the release of fume will also cause asphalt aging,segregation,cracking and other phenomena,shortening the life cycle of asphalt.At present,one of the methods to reduce the emission of asphalt fume is to add fume suppressant and deodorant to the asphalt.This method has a simple process and long-lasting effect.With the wide application of photocatalytic materials in the treatment of pollutants,titanium dioxide?Ti O₂?is favored because it is non-corrosive and non-toxic,will not cause secondary pollution,and has stable chemical properties;graphite carbon nitride?g-C₃N₄?,as a new metal-free semiconductor photocatalytic material,stands out because of its unique and controllable semiconductor energy band structure and morphology,simple synthesis process and excellent chemical stability.The paper selected Ti O₂,SBS and H₂O₂ as the components of asphalt fume suppressant and deodorant.The effects of Ti O₂ and SBS on asphalt fume?SBS synergy and the amount of oxidant added on the odor level were investigated respectively.Using four-component analysis,chromatographic analysis of fume components and thermogravimetric analysis to discuss the mechanism of action of fume suppression and deodorant,and finally analyze the performance of asphalt.The results show that when the amount of Ti O₂ is0.2%,the emission of asphalt fume is reduced by 50%,and when the amount of SBS is 1%,it reduces the emission of fume and overcomes the shortcomings of the admixture's damage to asphalt performance When the amount of H₂O₂added is 0.2%,the smoke odor level drops to 0;through four-component analysis,it was found that the addition of fume and deodorant reduced the saturation of the base asphalt and increased the gum and asphaltene.The agent can absorb the light components of asphalt and form a three-dimensional network structure in the asphalt.Ti O₂ improves the anti-ultraviolet aging performance and short-term thermal oxygen aging performance of 90^#asphalt.The paper added g-C₃N₄ to the asphalt,and investigated the influence of g-C₃N₄ on the emission of asphalt fume.The effect of g-C₃N₄ on the composition of asphalt fume was analyzed by chromatography.The structure of aromatic hydrocarbons was determined.XRD was used to characterize the lattice of g-C₃N_4.Thermogravimetric analysis and scanning electron microscopy discussed the mechanism of action of g-C₃N₄,and finally analyzed the performance of asphalt.The results show that addition of 0.5%g-C₃N₄ has a good inhibitory effect on the release of asphalt fume;liquid chromatography and infrared spectroscopy analysis show that the addition of g-C₃N₄ can reduce the content of PAHs in the asphalt fume,g-C₃N₄ can pass Hydrogen bonds and lattices can adsorb polycyclic aromatic hydrocarbons and long-chain alkanes in the asphalt;XRD analysis showed that the crystallinity of g-C₃N₄ in asphalt was slightly reduced,and it may be that the light component in asphalt was inserted into the layered structure of g-C₃N₄;electron microscope and polarized microscope observation that g-C₃N₄agglomerates when the amount of asphalt added is greater than 1%;by comparing with the performance of SBS modified road asphalt,after adding g-C₃N₄,the road performance of asphalt meets the standard requirements of road asphalt.