用于汽车废气处理的多孔性材料

Abstract

挤压成型的堇青石质蜂窝反应器是常用的汽车尾气净化装置，它的热稳定性好，耐久性高，而薄壁形的耐久性和催化活性又有所改进。采用适当溶剂、控制多组分醇类金属化合物水解的溶胶-凝胶法是制备优质堇青石和Al＿2O＿3基高温大比表面材料的新技术，在汽车尾气净化器的制作中将发挥独特的作用。金属载体牢固、传热性好。适当选择蜂窝的孔密度或构型，可得到起燃性好的催化转化器，这对克服汽车冷启动或热启动时过多的有害气体的排放有好处。

Extruded cordierite monolithic substrates are widely used as automotive catalyticconverters.They have high thermal shock resistanceand durability. The thrust in the ceramics area hascentered on thin-wall structure to meet the higherconversion eFFiciency and durability requirements ofthe converter systems, The Fundamental expansionincompatibility between cordierite ceramic andalumina washcoat must be managed properly. Thecomplexing agentassisted sol-gel method is intendedto regulate the hydrolysis and dehydration- condensation-polymerization of metal ion orcomplexes with polyFunctional organic compounds.Itis used to synthesize cordierite with betterthermostable property. For the metallic substrate,the changes in cell density and the conFigurationgreatly aFFected the light-ofF perFormance,whichwas improved as the thermal inertia was reduced,i.e.as the cell density was lowered.This advantageminimised the time taken For the catalysts to attaintheir working temperature and thereby achievedsigniFicant reductions in toxic emissions.PerFormance advantages of the Horringbone(HB)unlts should allow prominent downsizing to make itscosts very competitive.