气相转移法在堇青石蜂窝陶瓷上负载MnAPO-5分子筛

采用气相转移法在堇青石蜂窝陶瓷上负载MnAPO-5分子筛,制备了MnAPO-5/堇青石蜂窝陶瓷复合材料;考察了合成液中水含量、模板剂用量、铝源、浸泡次数和浸泡时间等对分子筛合成的影响,通过XRD、SEM和BET等方法对合成产物进行了表征。表征结果显示,合成液中n(H2O)∶n(Al2O3)=100时,堇青石蜂窝陶瓷上形成约70μm厚的MnAPO-5分子筛层,分子筛晶形较好;合成液中加入三乙胺(TEA)有利于MnAPO-5分子筛的负载,但过量的TEA会导致凝胶转化为MnAPO-34分子筛;改变浸泡次数可得到不同负载量的MnAPO-5/堇青石蜂窝陶瓷复合材料,而浸泡时间对MnAPO-5分子筛负载量的影响不大;分别以异丙醇铝和拟薄水铝为铝源时,前者的MnAPO-5分子筛负载量较大。

Supporting MnAPO-5 Molecular Sieves on Cordierite Honeycomb Monolith by Vapor Phase Transport

MnAPO-5 molecular sieves/cordierite honeycomb monolith composite was prepared through supporting MnAPO-5 molecular sieves on cordierite honeycomb monolith by vapor phase transport.Effects of n(H_2O)∶n(Al_2O_3),triethylamine(TEA) dosage,aluminum source,impregnation times and impregnation time on MnAPO-5 loading on the monolith were investigated.The products were characterized by means of XRD,SEM,and BET.When the monolith was impregnated in precursor solution with n(H_2O)∶n(Al_2O_3) 100,the composite with about 70 μm thickness MnAPO-5 layer and good crystal form could be obtained.When the precursor solution with TEA was added,high crystalline MnAPO-5 could be synthesized.However,excessive TEA would lead to formation of MnAPO-34.It was found that the loading of MnAPO-5 on the monolith could be controlled by changing the impregnation times,not the impregnation time.The loading of MnAPO-5 with aluminum isopropoxide as aluminum source was more than that with pseudoboehmite as aluminum source.