汽车尾气净化催化剂中催化涂层与蜂窝陶瓷载体结合强度的探究及控制  

Study andcontrol of the adhesive strength between catalytic coating and honeycomb ceramic carrier in automobile exhaust purification catalyst

作　　者：梁银 洪武 施鸿 杨冬霞 吴祥 Liang Yin;Hong Wu;Shi Hong;Yang Dongxia;Wu Xiang(Kunming Sino-Platinum Metals Catalyst Co.,Ltd,Kunming 650000,Yunnan,China)

机构地区：[1]昆明贵研催化剂有限责任公司,云南昆明650000

出　　处：《工业催化》2020年第11期44-49,共6页Industrial Catalysis

摘　　要：通过挤压填充-真空抽吸的涂覆方式将不同浆料分别涂覆于不同蜂窝陶瓷载体制得汽车尾气净化催化剂,通过测试评估涂层脱落率、光学显微镜观察涂层界面形貌、压汞仪测试微孔孔径及粒径仪测试物料粒径来研究催化材料涂层与载体间结合强度。结果表明:(1)微孔孔径D90·孔容积为(1.95~6.08)μm·(cm^3·g^-1)的载体与粒径D50=(0.80~1.39)μm、D90=(1.54~35.01)μm的涂层材料浆料相结合制得涂层的牢固性好,脱落率仅为0.16%~0.25%;(2)粒径D50=0.80μm、D90=1.54μm的涂层浆料,与孔径D90·孔容积为1.18~6.08μm·(cm^3·g)-1的载体均具有较好的匹配性,制得涂层牢固性较好,涂层脱落率为0.17%~0.22%;(3)大粒径涂层浆料制得涂层与载体间结合强度随载体网格微孔孔径D90·孔容积的增大而增强;涂覆于网格微孔较小载体的催化涂层与载体间结合强度随涂层浆料内颗粒粒径D50、D90的降低而增强。调整载体微孔孔径大小分布或涂层材料物料颗粒大小分布是调节涂层牢固性的关键方法。Automobile exhaust purification catalysts ware prepared from different slurries and carriers by extrusion filling-vacuum drawing way.The adhesive strength between catalytic coating and ceramic carrier was studied by measuring the peeling rate of coating,observing the microstructure of coatings and interfaces by optical microscope,measuring the pore diameter and particle diameter by mercury porosimeter and laser particle analyzer respectively.The study results indicate that:(1)The coatings prepared by carriers with the product of pore diameter D90 and pore volume of(1.95-6.08)μm·(cm^3·g^-1)and slurries with particle diameter D50=(0.80-1.39)μm and D90=(1.54-35.01)μm have good adhesion on carrier,the peeling rate of which is 0.16%~0.25%;(2)The coatings prepared by slurry with particle diameter D50=0.80μm and D90=1.54μm and carriers with the product of pore diameter D90 and pore volume of(1.18-6.08)μm·(cm^3·g^-1)have a good adhesion on carrier,the peeling rate of which is 0.17%~0.22%;(3)The adhesive strength of the coatings prepared by large particle diameter slurries increases with the increase of the product of pore diameter D90 and pore volume for carriers.The adhesive strength of the coatings prepared by small pore diameter carriers increases with the decrease of particle diameter(D50 and D90)for slurries.Adjusting the pore diameter of carrier or the particle diameter of slurry is an important way to control the adhesive strength between catalytic coating and ceramic carrier.

关 键 词：催化剂工程 催化涂层 陶瓷载体 结合强度 脱落率 孔径 粒径 

分 类 号：TQ426.96[化学工程] O643.36[理学—物理化学]