Use of Alkylarsonium Directing Agents for the Synthesis and Study of Zeolites

Abstract

This is the peer reviewed version of the following article: Chem. Eur. J. 2019, 25, 16390 16396 , which has been published in final form at https://doi.org/10.1002/chem.201904043. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. ; [EN] Expanding the previously known family of -onium (ammonium, phosphonium, and sulfonium) organic structure-directing agents (OSDAs) for the synthesis of zeolite MFI, a new member, the arsonium cation, is used for the first time. The new group of tetraalkylarsonium cations has allowed the synthesis of the zeolite ZSM-5 with several different chemical compositions, opening a route for the synthesis of zeolites with a new series of OSDA. Moreover, the use of As replacing N in the OSDA allows the introduction of probe atoms that facilitate the study of these molecules by powder X-ray diffraction (PXRD), solid-state nuclear magnetic resonance (MAS NMR), and X-ray absorption spectroscopy (XAS). Finally, the influence of trivalent elements such as B, Al, or Ga isomorphically replacing Si atoms in the framework structure and its interaction with the As species has been studied. The suitability of the tetraalkylarsonium cation for carrying out the crystallization of zeolites is demonstrated along with the benefit of the presence of As atoms in the occluded OSDA, which allows its advanced characterization as well as the study of its evolution during OSDA removal by thermal treatments. ; Program Severo Ochoa SEV-2016-0683 and Maria de Maeztu MDM-2015-0538 are gratefully acknowledged. S.S-F. thanks MEC for his Severo Ochoa Grant SPV-2013-067884, P.O.-B. and G.M.E. thank MEC for his Ramon y Cajal contracts (RYC-2014-16620 and RYC-2013-14386). The authors thank the financial support by the Spanish Government (RTI2018-096399-A-I00, RTI2018-101784-B-I00 and CTQ2017-89528-P) and the Generalitat Valeciana (PROMETEO/2017/066). The Electron Microscopy Service of the UPV is acknowledged for their help in sample characterization. We ...