Mavrodinova V, Popova M, Valchev V, Nickolov R, Minchev Ch
Institute of Organic Chemistry, Bulgarian Academy of Sciences, Sofia 1113, Bulgaria.
J Colloid Interface Sci. 2005 Jun 1;286(1):268-73. doi: 10.1016/j.jcis.2005.01.006.
Zeolite-based composite materials prepared by the embedding of the beta zeolite nanophase from aqueous colloidal solution into matrices of preformed Si(Al)MCM-41 mesoporous molecular sieves have been characterized by different methods (XRD, SEM, FTIR, N2 adsorption, and TPD of NH3). Their potential as catalysts for toluene disproportionation has been compared to mechanical mixtures of freeze-dried nanobeta crystallites with Si(Al)MCM-41 mesoporous materials. It is found that the zeolite catalyst efficiency is not substantially changed by the presence of mesopores belonging to the matrix. It is suggested that formation of intergrown aggregates from the colloidal nanobeta particles provides own highly developed textural mesoporosity that makes the contribution of the diffusional alleviation of the support negligible.
通过将β沸石纳米相从水性胶体溶液中嵌入预制的Si(Al)MCM - 41介孔分子筛基质中制备的沸石基复合材料，已通过不同方法（XRD、SEM、FTIR、N2吸附和NH3的TPD）进行了表征。已将它们作为甲苯歧化催化剂的潜力与冻干的纳米β微晶与Si(Al)MCM - 41介孔材料的机械混合物进行了比较。发现属于基质的介孔的存在并没有实质性改变沸石催化剂的效率。有人提出，由胶体纳米β颗粒形成的共生聚集体提供了自身高度发达的结构介孔性，这使得载体扩散缓解的贡献可以忽略不计。
