Preparation of SiC Hollow Spheres by Template Method and its Performance of Purification and Regeneration

Abstract

SiC hollow spheres were prepared by template mothod with polyethylene ball.The phase composition, morphology, momicrostructure, porosity and resistivity of the SiC hollow spheres were characterized by X-ray diffration, scanning electron microscopy, porosity test and voltammetry. The mechanism for formation of porous hollow pheres were discussed. The purification efficiency and performance of regeneration under ohmic heating were investigated using the prepared SiC hollow spheres for adsorbing particles in exhaust gas of diesel engine. The results show that the SiC hollow spheres comprise inner hollow and outer shell with much more micropores, and the thickness of the shells with microporosity having 80-120 nm is obout 300μm，The SiC hollow spheres consists mainly α-SiC, β-SiC and with a small quantity C, SiO2 and free Si. The purification efficiency could reach to 94 % or more for adsorbing particles in exhaust gas of diesel engine exhaust gas in 90 min because of its especial pore structure. Within ohmic heating, the SiC hollow spheres could work in a constant state of purification and and can its efficiency of purification could reach to 96% or more of efficiency in 180 min because of its excellent electro-heating performance.