新型柴油机尾气净化载体及其再生性能研究

Study on a novel carrier for diesel exhaust purification and its regeneration efficiency

用三维贯通网络结构的SiC多孔陶瓷作为柴油机尾气微粒净化用载体材料,研究了SiC多孔陶瓷的性能及其对柴油机尾气微粒净化效率及再生性能。结果表明,所制备的SiC多孔陶瓷以-αSiC、-βSiC和Si等为主晶相,具有宏孔(主孔)和微孔相结合的孔结构和良好的导电性能;SiC多孔陶瓷用作柴油机尾气净化载体材料,在通电和不通电2种情况下,可以实现对柴油机尾气微粒的过滤和净化。静态再生实验结果表明,供氧时再生效率可达93%;动态再生实验结果表明,通20 V电压150 s后净化效率能达到76%,且背压始终小于380 Pa,说明通电时SiC多孔陶瓷的加热效果良好,通电时可以实现微粒持续的过滤、净化,同时使多孔陶瓷载体处于持续的再生状态。

SiC porous ceramics with three-dimensional solid net framework structure was applied as carrier for purifying particles in diesel exhaust.The purification performance and regenerability of this carrier was studied.The results showed that α-SiC,β-SiC and free Si were the main crystalline phase of SiC porous ceramics.The main pore diameter was about 300-400 μm with micropore uneven distributed throughout the porous body.The carrier had excellent electric conductivity,so it was a perfect carrier material for purifying particles in diesel exhaust.The particle in diesel exhaust could be filtered and purified in both cases of porous ceramics electrified or not.Static regeneration experiment showed that regeneration efficiency could reach to 93% or more under aerobic conditions.Dynamic regeneration experiment showed that purifying efficiency could reach to 76% at 20 V for 150 s,and the residual pressure still lower than 380 Pa.The SiC porous ceramic could achieve particulate filtration and purification while the porous ceramics were in a state of constant regeneration when electric current was applied.