Research On Phosphorus Slag Powder Surface Modification And Its Influence On Performance Of Asphalt

Phosphorus slag,an industrial waste,which is discharged in the production process of yellow phosphorus.With the progress of science and technology,as well as the continuous updates and applications of equipment and technology,phosphorus slag is used extensively in all fields of industrial production.Phosphorus slag powder modified asphalt can be improved on the relative performance,by adding finely ground phosphorus slag powder into the matrix asphalt.However,phosphorus slag powder is difficult to disperse uniformly in the asphalt yet,because of the hydrophilic and oleophobic surface polarity.In addition,the powder is easy to reunite,in result of small size.The above issues extremely affect the performance of phosphorus slag powder in the asphalt.Currently,surface modification technology can effectively solve these problems,but researches on surface modification of phosphorus slag powder is not reported.Therefore,it is greatly important to study and select the suitable surface modifier for the surface modification of phosphorus slag powder,which is of great significance for the application of phosphorus slag powder in asphalt.Phosphorus slag powder surface modification and its influence on the performance of asphalt are studied by experimental test.Five kinds of surface modifier are selected for surface modification of phosphorus slag powder,whose effects are evaluated by wettability and oil absorption test,and then,both optimal modifier and reasonable modification conditions are determined.Surface characteristics and modification mechanism of phosphorus slag powder particles are studied by infrared spectroscopy and scanning electron microscopy test.The matrix asphalt with 10% of the phosphorus-modified slag powder is used as the research object,and then,the high temperature anti-rutting performance,fatigue resistance and low temperature crack resistance of modified phosphorus slag powder asphalt are tested by SHRP test method.The anti-aging properties and the mechanism of phosphorus slag powder asphalt are analyzed through the infrared spectrum test and dynamic shear test(DSR).Finally,the effect of modified phosphate slag powder on pavement performance of asphalt mixture is evaluated by means of marshall test,rutting test and freeze-thaw splitting test.The results show that,when phosphate type single alkyl oxygen base titanate TM-P is used for surface modifier,the phosphorus slag powder has a better surface modification effect than usual,with the reaction time of 35 min,reaction temperature of 70?,and TM-P addition of 2.5%.The phosphorus slag powder modified by TM-P is well dispersed in the asphalt,and both high temperature anti-rutting and anti-aging performance are improved.In terms of asphalt mixture,high temperature anti-rutting performance and anti-water damage property are greatly enhanced by adding modified phosphorus slag powder.