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Title: Broadening the Scope for Fluoride‐Free Synthesis of Siliceous Zeolites

Abstract

Abstract Siliceous zeolites are ideally suited for emerging applications in gas separations, sensors, and the next generation of low‐ k dielectric materials, but the use of fluoride in the synthesis significantly hinders their commercialization. Herein, we show that the dry gel conversion (DGC) technique can overcome this problem. Fluoride‐free synthesis of two siliceous zeolites—AMH‐4 (CHA‐type) and AMH‐5 (STT‐type), has been achieved for the first time using the method. Siliceous *BEA‐, MFI‐, and *MRE‐type zeolites have also been synthesized to obtain insights into the crystallization process. Charge‐balancing interactions between the inorganic cation, organic structure‐directing agent (OSDA), and Si−O defects are found to be an essential aspect. We quantify this factor in terms of the “OSDA charge/silica ratio” of the as‐made zeolites and demonstrate that the DGC technique is broadly applicable and opens up new avenues for fluoride‐free siliceous zeolite synthesis.

Authors:
ORCiD logo [1];  [1];  [2];  [3]; ORCiD logo [1]
  1. Department of Chemical Engineering University of Massachusetts Amherst 686 N Pleasant St Amherst MA 01003 USA
  2. Department of Polymer Science &, Engineering University of Massachusetts Amherst 120 Governor's Dr Amherst MA 01003 USA
  3. Department of Chemical Engineering University of Massachusetts Amherst 686 N Pleasant St Amherst MA 01003 USA, School of Chemical Engineering Northwest University Xi'an Shanxi 710069 China
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1422019
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Angewandte Chemie (International Edition)
Additional Journal Information:
Journal Name: Angewandte Chemie (International Edition) Journal Volume: 57 Journal Issue: 14; Journal ID: ISSN 1433-7851
Publisher:
Wiley Blackwell (John Wiley & Sons)
Country of Publication:
Germany
Language:
English

Citation Formats

Vattipalli, Vivek, Paracha, Abdul Mughis, Hu, Weiguo, Chen, Huiyong, and Fan, Wei. Broadening the Scope for Fluoride‐Free Synthesis of Siliceous Zeolites. Germany: N. p., 2018. Web. doi:10.1002/anie.201712684.
Vattipalli, Vivek, Paracha, Abdul Mughis, Hu, Weiguo, Chen, Huiyong, & Fan, Wei. Broadening the Scope for Fluoride‐Free Synthesis of Siliceous Zeolites. Germany. https://doi.org/10.1002/anie.201712684
Vattipalli, Vivek, Paracha, Abdul Mughis, Hu, Weiguo, Chen, Huiyong, and Fan, Wei. 2018. "Broadening the Scope for Fluoride‐Free Synthesis of Siliceous Zeolites". Germany. https://doi.org/10.1002/anie.201712684.
@article{osti_1422019,
title = {Broadening the Scope for Fluoride‐Free Synthesis of Siliceous Zeolites},
author = {Vattipalli, Vivek and Paracha, Abdul Mughis and Hu, Weiguo and Chen, Huiyong and Fan, Wei},
abstractNote = {Abstract Siliceous zeolites are ideally suited for emerging applications in gas separations, sensors, and the next generation of low‐ k dielectric materials, but the use of fluoride in the synthesis significantly hinders their commercialization. Herein, we show that the dry gel conversion (DGC) technique can overcome this problem. Fluoride‐free synthesis of two siliceous zeolites—AMH‐4 (CHA‐type) and AMH‐5 (STT‐type), has been achieved for the first time using the method. Siliceous *BEA‐, MFI‐, and *MRE‐type zeolites have also been synthesized to obtain insights into the crystallization process. Charge‐balancing interactions between the inorganic cation, organic structure‐directing agent (OSDA), and Si−O − defects are found to be an essential aspect. We quantify this factor in terms of the “OSDA charge/silica ratio” of the as‐made zeolites and demonstrate that the DGC technique is broadly applicable and opens up new avenues for fluoride‐free siliceous zeolite synthesis.},
doi = {10.1002/anie.201712684},
url = {https://www.osti.gov/biblio/1422019}, journal = {Angewandte Chemie (International Edition)},
issn = {1433-7851},
number = 14,
volume = 57,
place = {Germany},
year = {Wed Feb 21 00:00:00 EST 2018},
month = {Wed Feb 21 00:00:00 EST 2018}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at https://doi.org/10.1002/anie.201712684

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Works referenced in this record:

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In particular, we have observed variation in Raman intensities of F<sup>–</sup>/D4R and empty D4R bands during LTA crystallization; periodic DFT calculations indicate that the observed Raman behavior is consistent with empty D4R units containing one or two Si vacancies surrounded by Q<sub>3</sub> Si—consistent also with solid-state nuclear magnetic resonance measurement. These defects appear to heal during further crystallization, leading to the formation of defect-free LTA zeolite crystals. Altogether, our results provide deeper understanding on the roles of F<sup>–</sup> in charge balancing and stabilizing intact D4R units during zeolite formation.</span><a href='#' onclick='$(this).hide().prev().hide().prev().show();return false;' style='margin-left:10px;display:none;'>« less</a></div><div class="metadata-links small clearfix text-muted" style="margin-top:15px;"> <div class="pure-menu pure-menu-horizontal pull-right" style="width:unset;"> <ul class="pure-menu-list"> <li class="pure-menu-item"><span class="item-info-ftlink"><a class="misc doi-link " href="https://doi.org/10.1021/acs.chemmater.1c01420" target="_blank" rel="noopener" title="Link to document DOI" data-ostiid="1830688" data-product-type="Journal Article" data-product-subtype="AM" >https://doi.org/10.1021/acs.chemmater.1c01420</a></span></li> <li class="pure-menu-item"><span class="item-info-ftlink"><a class="misc fulltext-link " href="/servlets/purl/1830688" title="Link to document media" target="_blank" rel="noopener" data-ostiid="1830688" data-product-type="Journal Article" data-product-subtype="AM" >Full Text Available</a></span></li> </ul> </div> </div> </div> <div class="clearfix"></div> </div> </li> <li> <div class="article item document" itemprop="itemListElement" itemscope itemtype="http://schema.org/WebPage"><meta itemprop="position" content="2" /><div class="item-info"> <h2 class="title" itemprop="name headline"><a href="/biblio/1866156" itemprop="url">Titrating Controlled Defects into Si-LTA Zeolite Crystals Using Multiple Organic Structure-Directing Agents</a></h2> <div class="metadata"> <small class="text-muted" style="text-transform:uppercase;display:block;line-height:2.5em;">Journal Article</small><span class="authors"> <span class="author">Luo, Song</span>; <span class="author">Wang, Tongkun</span>; <span class="author">Qi, Long</span>; <span class="author">...</span> <span class="text-muted pubdata"> - Chemistry of Materials</span> </span></div> <div class="abstract">Controlling defects in zeolites is crucial for tuning their adsorption and catalytic properties. In this work, we have performed an integrated zeolite synthesis, spectroscopy, and density functional theory study to test the limit of F– as a charge-balancing agent that mitigates defects in siliceous zeolites. We focused on the synthesis of siliceous zeolite LTA at 150 °C with 1,2-dimethyl-3-(4-methylbenzyl) imidazolium as the primary organic structure-directing agent (OSDA) and tetramethyl ammonium (TMA) as the secondary OSDA. By varying the amount of TMA in the synthesis gel, positive charges were titrated into the resulting as-made Si-LTA. Surprisingly, we found that greater TMA<a href='#' onclick='$(this).hide().next().show().next().show();return false;' style='margin-left:10px;'>more »</a><span style='display:none;'> concentration does not induce more F– to enter into the zeolite. 29Si solid-state MAS NMR, Raman spectroscopy, and density functional theory suggest that this system has surpassed its capacity for F– to balance OSDA charge, and additional positive charge is balanced by Si–O– framework defects. The number of defects in the as-made Si-LTA can be precisely titrated by the amount of TMA in the zeolite structures. For the Si-LTA synthesized without TMA, framework defects formed in the early stage of crystal growth were found to heal during later crystallization, leading to defect-free Si-LTA. However, for the Si-LTA synthesized with TMA, the defects formed in early stages do not heal. A DFT thermodynamic analysis explains that crowding of Si-LTA pores by TMA impedes defect healing; this prediction is corroborated by synthesis experiments at an elevated temperature (170 °C). These results indicate that F– can have a limited capacity to balance OSDA charge in zeolite synthesis, opening up a third route to zeolite synthesis intermediate between the fluoride and hydroxide routes.</span><a href='#' onclick='$(this).hide().prev().hide().prev().show();return false;' style='margin-left:10px;display:none;'>« less</a></div><div class="metadata-links small clearfix text-muted" style="margin-top:15px;"> <div class="pure-menu pure-menu-horizontal pull-right" style="width:unset;"> <ul class="pure-menu-list"> <li class="pure-menu-item"><span class="item-info-ftlink"><a class="misc doi-link " href="https://doi.org/10.1021/acs.chemmater.1c04036" target="_blank" rel="noopener" title="Link to document DOI" data-ostiid="1866156" data-product-type="Journal Article" data-product-subtype="AM" >https://doi.org/10.1021/acs.chemmater.1c04036</a></span></li> <li class="pure-menu-item"><span class="item-info-ftlink"><a class="misc fulltext-link " href="/servlets/purl/1866156" title="Link to document media" target="_blank" rel="noopener" data-ostiid="1866156" data-product-type="Journal Article" data-product-subtype="AM" >Full Text Available</a></span></li> </ul> </div> </div> </div> <div class="clearfix"></div> </div> </li> <li> <div class="article item document" itemprop="itemListElement" itemscope itemtype="http://schema.org/WebPage"><meta itemprop="position" content="3" /><div class="item-info"> <h2 class="title" itemprop="name headline"><a href="/biblio/1401665" itemprop="url">Open‐Pore Two‐Dimensional MFI Zeolite Nanosheets for the Fabrication of Hydrocarbon‐Isomer‐Selective Membranes on Porous Polymer Supports</a></h2> <div class="metadata"> <small class="text-muted" style="text-transform:uppercase;display:block;line-height:2.5em;">Journal Article</small><span class="authors"> <span class="author">Zhang, Han</span>; <span class="author">Xiao, Qiang</span>; <span class="author">Guo, Xianghai</span>; <span class="author">...</span> <span class="text-muted pubdata"> - Angewandte Chemie</span> </span></div> <div class="abstract">Abstract Two‐dimensional zeolite nanosheets that do not contain any organic structure‐directing agents were prepared from a multilamellar MFI (ML‐MFI) zeolite. ML‐MFI was first exfoliated by melt compounding and then detemplated by treatment with a mixture of H <sub>2</sub> SO <sub>4</sub> and H <sub>2</sub> O <sub>2</sub> (piranha solution). The obtained OSDA‐free MFI nanosheets disperse well in water and can be used for coating applications. Deposits made on porous polybenzimidazole (PBI) supports by simple filtration of these suspensions exhibit an n ‐butane/isobutane selectivity of 5.4, with an n ‐butane permeance of 3.5×10 <sup>−7</sup>  mol m <sup>−2</sup>  s <sup>−1</sup>  Pa <sup>−1</sup> (ca. 1000 GPU).</div><div class="metadata-links small clearfix text-muted" style="margin-top:15px;"> <div class="pure-menu pure-menu-horizontal pull-right" style="width:unset;"> <ul class="pure-menu-list"> <li class="pure-menu-item"><span class="item-info-ftlink"><a class="misc doi-link " href="https://doi.org/10.1002/ange.201601135" target="_blank" rel="noopener" title="Link to document DOI" data-ostiid="1401665" data-product-type="Journal Article" data-product-subtype="PM" >https://doi.org/10.1002/ange.201601135</a></span></li> </ul> </div> </div> </div> <div class="clearfix"></div> </div> </li> <li> <div class="article item document" itemprop="itemListElement" itemscope itemtype="http://schema.org/WebPage"><meta itemprop="position" content="4" /><div class="item-info"> <h2 class="title" itemprop="name headline"><a href="/biblio/1400963" itemprop="url">Open‐Pore Two‐Dimensional MFI Zeolite Nanosheets for the Fabrication of Hydrocarbon‐Isomer‐Selective Membranes on Porous Polymer Supports</a></h2> <div class="metadata"> <small class="text-muted" style="text-transform:uppercase;display:block;line-height:2.5em;">Journal Article</small><span class="authors"> <span class="author">Zhang, Han</span>; <span class="author">Xiao, Qiang</span>; <span class="author">Guo, Xianghai</span>; <span class="author">...</span> <span class="text-muted pubdata"> - Angewandte Chemie (International Edition)</span> </span></div> <div class="abstract">Abstract Two‐dimensional zeolite nanosheets that do not contain any organic structure‐directing agents were prepared from a multilamellar MFI (ML‐MFI) zeolite. ML‐MFI was first exfoliated by melt compounding and then detemplated by treatment with a mixture of H <sub>2</sub> SO <sub>4</sub> and H <sub>2</sub> O <sub>2</sub> (piranha solution). The obtained OSDA‐free MFI nanosheets disperse well in water and can be used for coating applications. Deposits made on porous polybenzimidazole (PBI) supports by simple filtration of these suspensions exhibit an n ‐butane/isobutane selectivity of 5.4, with an n ‐butane permeance of 3.5×10 <sup>−7</sup>  mol m <sup>−2</sup>  s <sup>−1</sup>  Pa <sup>−1</sup> (ca. 1000 GPU).</div><div class="metadata-links small clearfix text-muted" style="margin-top:15px;"> <span class="fa fa-book text-muted" aria-hidden="true"></span> Cited by 91<div class="pure-menu pure-menu-horizontal pull-right" style="width:unset;"> <ul class="pure-menu-list"> <li class="pure-menu-item"><span class="item-info-ftlink"><a class="misc doi-link " href="https://doi.org/10.1002/anie.201601135" target="_blank" rel="noopener" title="Link to document DOI" data-ostiid="1400963" data-product-type="Journal Article" data-product-subtype="PM" >https://doi.org/10.1002/anie.201601135</a></span></li> </ul> </div> </div> </div> <div class="clearfix"></div> </div> </li> </ul> </aside> </div> </section> </div> <div class="col-sm-3 order-sm-3"> <ul class="nav nav-stacked"> <li class="active"><a class="tab-nav disabled" data-tab="related" style="color: #636c72 !important; opacity: 1;"><span class="fa fa-angle-right"></span> Similar Records</a></li> </ul> </div> </div> </section> </div></div> </div> </div> </section> <footer class="" style="background-color:#f9f9f9; /* padding-top: 0.5rem; */"> <div class="footer-minor"> <div class="container"> <hr class="footer-separator" /> <div class="text-center" style="margin-top:1.25rem;"> <div class="pure-menu pure-menu-horizontal"> <ul class="pure-menu-list" id="footer-org-menu"> <li class="pure-menu-item d-block d-inline-small"> <a href="https://energy.gov" target="_blank" rel="noopener noreferrer"> <img src="data:image/gif;base64,R0lGODlhAQABAIAAAP///wAAACH5BAEAAAAALAAAAAABAAEAAAICRAEAOw==" class="sprite sprite-footer-us-doe-min" alt="U.S. Department of Energy" /> </a> </li> <li class="pure-menu-item d-block d-inline-small"> <a href="https://www.energy.gov/science/office-science" target="_blank" rel="noopener noreferrer"> <img src="data:image/gif;base64,R0lGODlhAQABAIAAAP///wAAACH5BAEAAAAALAAAAAABAAEAAAICRAEAOw==" class="sprite sprite-footer-office-of-science-min" alt="Office of Science" /> </a> </li> <li class="pure-menu-item d-block d-inline-small"> <a href="/"> <img src="data:image/gif;base64,R0lGODlhAQABAIAAAP///wAAACH5BAEAAAAALAAAAAABAAEAAAICRAEAOw==" class="sprite sprite-footer-osti-min" alt="Office of Scientific and Technical Information" /> </a> </li> </ul> </div> </div> <div class="text-center small" style="margin-top:0.5em;margin-bottom:2.0rem;"> <div class="pure-menu pure-menu-horizontal"> <ul class="pure-menu-list"> <li class="pure-menu-item"><a href="/disclaim" class="pure-menu-link"><span class="fa fa-institution"></span> Website Policies <span class="d-none d-sm-inline" style="color:#737373;">/ Important Links</span></a></li> <li class="pure-menu-item"><a href="/contact" class="pure-menu-link"><span class="fa fa-comments-o"></span> Contact Us</a></li> <li class="d-block d-md-none mb-1"></li> <li class="pure-menu-item"><a href="https://doe.responsibledisclosure.com/hc/en-us" target="_blank" class="pure-menu-link">Vulnerability Disclosure Program</a></li> <li class="d-block d-lg-none mb-1"></li> <li class="pure-menu-item"><a href="https://www.facebook.com/ostigov" target="_blank" rel="noopener noreferrer" class="pure-menu-link social"><span class="fa fa-facebook"></span><span class="sr-only">Facebook</span></a></li> <li class="pure-menu-item"><a href="https://twitter.com/OSTIgov" target="_blank" rel="noopener noreferrer" class="pure-menu-link social"><span class="fa fa-twitter"></span><span class="sr-only">Twitter</span></a></li> <li class="pure-menu-item"><a href="https://www.youtube.com/user/ostigov" target="_blank" rel="noopener noreferrer" class="pure-menu-link social"><span class="fa fa-youtube-play"></span><span class="sr-only">YouTube</span></a></li> </ul> </div> </div> </div> </div> </footer> <link href="/css/ostigov.fonts.240327.0425.css" rel="stylesheet"> <script src="/js/ostigov.240327.0425.js"></script><noscript></noscript> <script defer src="/js/ostigov.biblio.240327.0425.js"></script><noscript></noscript> <script async type="text/javascript" src="/js/Universal-Federated-Analytics-Min.js?agency=DOE" id="_fed_an_ua_tag"></script><noscript></noscript> </body> <!-- OSTI.GOV v.240327.0425 --> </html>