TiO_2改性乳化沥青薄层罩面的净化性能

Purification performance of thin layer cover of TiO_2 modified asphalt

基于纳米TiO_2可以催化降解汽车尾气,提出了纳米TiO_2改性乳化沥青薄层罩面的方法,定义了累积降解率和催化效能指数的评价体系,研发了配套试验仪器,分析了TiO_2粉体粒径、沥青中TiO_2质量分数、罩面厚度、温度以及紫外光辐照度对指标的影响,确定了最佳罩面厚度和TiO_2掺量.研究结果表明:TiO_2粉体粒径为25 nm以及TiO_2掺量在10%左右时,累积降解率和催化效能均达到最大;随着温度和紫外光辐照度的增大,TiO_2催化降解尾气性能明显增大;随着罩面厚度不断增大,尾气降解总量不断增大后趋于平稳,而催化降解效率不断减小;推荐的材料制备优化方案为TiO_2质量分数为8.5%、薄层厚度为15.0 mm.

Based on the catalyzed decomposition ability of nano-TiO2 ,the thin layer cover of nano-TiO2 modified asphalt was put forward,and the index system of cumulative decomposition and catalytic performance was defined.A test instrument was developed,and the effects of TiO2 powder size,TiO2 content,layer thickness,temperature and irradiance on indicator changing trends and influencing degrees were analyzed to determine,the optimal scheme of thickness and content.The results show that when the TiO2 size is 25 nm with TiO2 content of 1 0%,the cumulative rate of decomposition and the catalytic efficiency index reach the maximum values.With the increasing of temperature and irradiance intensity, the performance of decomposition is improved markedly.When the spray volume is increased,the total gas decomposition is increased with latter stable,while the efficiency is decreased.To obtain good durability performance,the scheme of material parameters is recommended with TiO2 dosage of 8.5%and thickness of 1 5 .0 mm.