Recrystallization on Alkaline Treated Zeolites in the Presence of Pore-Directing Agents Eddy Dib Hussein El Siblani Shrikant M. Kunjir Aurelie Vicente Nicolas Nuttens Danny Verboekend Bert F. Sels Christian Fernandez 10.1021/acs.cgd.7b01416.s001 https://acs.figshare.com/articles/journal_contribution/Recrystallization_on_Alkaline_Treated_Zeolites_in_the_Presence_of_Pore-Directing_Agents/6002072 In previous works aiming at understanding the mesoporous network after alkaline treatment in the presence of organic additives, conventional bulk characterization techniques led to the conclusion that the dissolved zeolite does not undergo any kind of recrystallization [Verboekend, D., Cryst. Growth. Des. 2013, 13, 5025−5035]. Here for the first time, we demonstrate using the data obtained from <sup>1</sup>H and <sup>129</sup>Xe NMR spectroscopy that such recrystallization does occur, which leads to the formation of a very thin coating of the mesopore walls. This demonstration is done on a beta (BEA) zeolite treated in the presence of TPA<sup>+</sup> in an alkaline solution. The formation of a small amount of nanosized crystals or embryonic phases of silicalite-1 (MFI) zeolite is evidenced, as well as their homogeneous dispersion on the mesoporous surface of the beta zeolite. We think that these results may explain why a homogeneous mesopore size distribution is obtained, when organic pore-directing agents are used in the zeolite hierarchization process performed in an alkaline medium. 2018-03-14 00:00:00 129 Xe NMR spectroscopy beta zeolite BEA presence Alkaline Treated Zeolites nanosized crystals pore-directing agents zeolite hierarchization process recrystallization mesoporous network TPA mesopore walls 1 H mesopore size distribution formation bulk characterization techniques mesoporous surface Pore-Directing Agents MFI