Study On Activation And Function Of Recycled Powder Of Waste Concrete

In this paper,the recycled powder produced by the process of waste concrete was used as the research object,and the method of mechanochemical activation was used to activate the recycled powder to stimulate the activity and improve the utilization rate of the recycled powder.At the same time,the functional test of the recycled powder was carried out,and TiO2 was supported on the surface of the recycled powder to prepare a kind of fine powder with photocatalytic function.The specific contents are as follows:(1)The recycled powder was activated by superfine air pulverizer,and compared with that of the ball mill.The particle size distribution,micro-morphology and phase configuration of the recycled powders were tested by laser particle size analyzer,SEM and XRD.The results show that the recycled powder crushed by superfine air pulverizer is of narrow size distribution and regular particle shape,the sharp edges and corners of the surface are passivated,the degree of amorphous of SiO2 is high,and the activity is high.(2)The activated recycled powder by a certain proportion to replaced cement mixing in the mortar.The water consumption,the internal microstructure,and the compressive strength of mortar were tested by mortar consistency meter,SEM and pressure testing machine.The results show that the mortar mixed with the recycled powder grinding by superfine air pulverizer is of smaller water consumption,denser interior and high compressive strength.(3)Using recycled powder as matrix,tetrabutyl titanate(C16H36O4Ti)as titanium source,ethanol,nitric acid and deionized water as solvent.TiO2 was supported on the surface of the recycled powder by sol-gel method to prepare photocatalytic regeneration powder.The microscopic morphology,crystal structure and characteristics of functional groups and characterize the degradation rate of methyl orange solution were tested by SEM,XRD,EDS and FT-IR and uv-vis spectrophotometer The results show that TiO2 was successfully loaded on the surface of the recycled powder by sol-gel method,and the TiO2 coated on the surface of the recycled powder is anatase phase and the TiO2/regenerated powder composite particles have good photocatalytic degradation performance.