混合酸(HNO_3+HF)刻蚀法致霾汽车尾气过滤载体材料的设计与研究  

Design and Research of Automobile Exhaust Filter Material Prepared by Mixed Acid(HNO_3+HF)

作　　者：薛涛[1] 魏冬[1] 乔石[1] 孟家光[1] 

机构地区：[1]西安工程大学纺织工程与材料学院,西安710048

出　　处：《材料导报（纳米与新材料专辑）》2016年第1期117-120,共4页

基　　金：陕西省自然科学基金面上项目(2015JM5210);中国纺织工业联合会指导项目(2014006;2015032);陕西省重点实验室专项(15JS030);陕西省重点学科专项(陕[2008]169)

摘　　要：以纺织加工过程中废弃的棉短绒为模板,经过溶胶法浸渍形成棉纤维/氧化硅复合体,再经常温树脂固化、低温真空碳化、高温碳热还原反应及液相渗硅等方式制备出SiC/Si复合材料,最后通过混合酸(HNO3+HF)循环氧化腐蚀制备出过滤汽车尾气陶瓷载体材料。扫描电镜(SEM)结果显示,多孔SiC具有不规则且相互连通的孔道结构,其微观形貌特征遗传于棉短绒和酚醛树脂制备的多孔碳;三点弯曲试验表明SiC/Si陶瓷复合材料的强度高达200MPa,多孔SiC的气孔率可达62%,混合酸腐蚀的多孔SiC的弯曲强度和断裂韧性均小于致密SiC/Si复合体,并提出了混合酸循环氧化-腐蚀机制解释游离态Si的腐蚀过程。Put waste cotton linters as templates,dipped by sol method so as to form composition of cotton and SiO2,then through resin curing,low temperature vacuum carbonizing、high temperature carbonizing and liquid penetration of Si to become composition of SiC/Si,finally,through mixed acid（HNO3＋HF）oxidation corrosion repeatedly,prepared the ceramic carrier material in automobile exhaust treatment.SEM showed that SiC had irregular and interconnected pore structure.The microstructure depended on porous carbon made of cotton linters and phenol formaldehyde resin.Bending tests showed that the tenacity of SiC/Si ceramic composite researched 200 MPa,the porosity of SiC researched 62%,the bending strength and fracture toughness of SiC were lower than that of composition of SiC/Si.In the meanwhile,the cyclic oxidation mechanism of mixed acid was proposed to explain the corrosion process of Si.

关 键 词：棉短绒 混酸腐蚀 多孔碳化硅 循环氧化法 过滤材料 

分 类 号：TQ174[化学工程—陶瓷工业]