Development And Evaluation Of TiO₂-Based Auto Exhaust Degradation Asphalt Pavement Material

The health of urban residents in China has been threatened by haze,overweight PM2.5 in the air is the primary reason that causes haze.While the NOX and CO come from motor vehicle exhaust,combination with fine particles or ultrafine particles in the air are the main sources of PM2.5.As a kind of photocatalystic materials,nanometer titanium dioxide?nanometer titanium dioxide,Nano-TiO₂?can effectively degrade the automobile exhaust under light irradiation.This paper will apply the Nano-TiO₂ photocatalyst materials to the asphalt road surface layer and the surface,to confer the function of degradation of tail gas to asphalt pavement and make comprehensive evaluation of its performance.Firstly,this paper comparatively analyze the photocatalytic degradation,durability of photocatalytic degradation,pavement performance and economy effect of exhaust NOX,HC and CO three gases of Nano-TiO₂ in Asphalt Pavement manner at UV indoor irradiation conditions,and determine Nano-TiO₂ economic,effective and durable manner and the amount of application in asphalt pavement;Secondly,In view of the Nano-TiO₂ photocatalytic degradation efficiency is low,this paper non-metal doped Nano-TiO₂ by sol-gel method,preparation of a new composite doped Nano-TiO₂ and analysis exhaust degradation of asphalt pavement coated with composite doping Nano-TiO₂,and compared exhaust degradation performance with coating Nano-TiO₂ asphalt road;Finally,simulation analysis the photocatalytic degradation effect of asphalt pavement containing Nano-TiO₂ based photocatalyst materials in the road environment NO_x,HC and CO concentration levels,development outdoor light catalytic degradation simulation systems,and in visible outdoor light irradiation conditions,analysis the impact of Nano-TiO₂ based photocatalyst material addition amount of NOX and CO degradation and degradation height of pollutants.Compare degradation effects of Nano-TiO₂ and composite doped Nano-TiO₂ in the economic and effective amount.The results showed that: In UV indoor irradiation conditions,the exhaust NOX,HC and CO three gases photocatalytic degradation effect of containing Nano-TiO₂ asphalt road increased with Nano-TiO₂ add content increased.Wheel wear will reduce exhaust photocatalytic degradation of road material degradation.High-temperature performance,low temperature performance,water stability and surface skid resistance of asphalt pavement with Nano-TiO₂ still meet the specification requirements.After comprehensive analysis,it shows that add Nano-TiO₂ into the fog seal and sand fog seal and prepare coating solution applied to the asphalt road surface is an economical,effective and durable way and the economy and effective addition ratio is 2%.After a non-metallic composite doped Nano-TiO₂ coating to the surface of the asphalt pavemdent can effectively degrade exhaust NOX,HC and CO three gases,its economy and effective ratio is 2%,and the Nano-TiO₂ after non-metal doped photocatalytic degradation efficiency increased by 13% to 17%.In visible outdoor light irradiation conditions,coating Nano-TiO₂ based photocatalyst material in road surface,the photocatalytic degradation effects of exhaust NOX and CO is lower than the UV indoor irradiation conditions,but coating a composite doped Nano-TiO₂ degradation on the road surface,the photocatalytic degradation of NO_x and CO are still improved with composite doping Nano-TiO₂ addition ratio increased,and the ratio of the composite doped Nano-TiO₂ effect the degradation height of NO_x and CO,the NO_x and CO degradation height impact ranges of 0⁰.5m and 0m¹.0m under the economy and effective ratio of composite doped Nano-TiO₂,after nonmetal doped the photocatalytic degradation of Nano-TiO₂ will increase about 38% ⁴4%.