because i have tried out some reactions, those needs both type of pores.., then only selectivity and conversion was enhanced. while in clays its possible but active sites are not present inside the pore in most cases. but zeolites has active sites in pores itself.
Mesoporous zeolite single Crystal materials may be prepared also by crystallizing the zeolite around a carbon matrix that can eventually be removed by combustion.
The paper by K. Egeblad et al. (Microporous and Mesoporous Materials 101 (2007) 214–223) describes a combination of the fluoride route with a new improved procedure for directly introducing carbon in the reaction mixture, also for the zeolite BEA.
Several papers in the literature reported the formation of additional mesoporosity to the standar microporosity of the conventional zeolite-Beta, and thereby synthesizing hierarchical Beta zeolites.
Some examples:
María Dolores González, Pilar Salagre, María Linares, Rafael García, David Serrano, Yolanda Cesteros. "Effect of hierarchical porosity and fluorination on the catalytic properties of zeolite Beta for glycerol etherification" Aplied Catalysis A: General 473 (2014) 75–82 DOI: http://dx.doi.org/doi:10.1016/j.apcata.2013.12.038
Rafael A García-Muñoz, David P. Serrano, Gemma Vicente, María Linares, Dana Vitvarova, Jirí Cejka. "Remarkable Catalytic Properties of Hierarchical Zeolite-Beta in the Epoxide Rearrangement Reactions". Catalysis Today, 243 (2015) 141–152, DOI: 10.1016/j.cattod.2014.09.014
yes there are multiple methods for the preparation of mesoporous zeolite, you can use the nono tube of carbon in the gel of zeolite, you can use the desilication or dealumination of the zeolite, you can use the dissolution of the zeolite with a mixture with surfactant solution.
see
Bouhadjar Boukoussa, Nafissa Aouad, RachidaHamacha, Abdelkader Bengueddach. Journal of Physics and Chemistry of Solids 78 (2015) 78–83
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