caa a22 4500 606173897 CHVBK 20210128100735.0 cr unu---uuuuu 210128e20150501xx s 000 0 eng 10.1007/s11244-015-0384-y doi (NATIONALLICENCE)springer-10.1007/s11244-015-0384-y Effect of Pore and Cage Size on the Formation of Aromatic Intermediates During the Methanol-to-Olefins Reaction [Elektronische Daten] [Mark Deimund, Joel Schmidt, Mark Davis] Six eight-membered-ring (8MR), microporous materials are synthesized and evaluated as catalysts for the methanol-to-olefins (MTO) reaction. The molecular sieves SSZ-13, SAPO-34, SAPO-39, MCM-35, ERS-7 and RUB-37 are investigated since they have 8MR access to the crystal interior but have differences in pore structure and cage size. The polymethylbenzene species that are the proposed reaction intermediates of the MTO reaction should only be able to form in materials with intra-molecular sieve void spaces of sufficient size to accommodate them. Thus, it is hypothesized that 8MR materials without adequately large pores or cages will be inactive for the MTO reaction. SSZ-13 and SAPO-34 (both with CHA framework topology) have interconnected 3-dimensional pore-and-cage systems sufficiently large for formation of the proposed reaction intermediates, while the other 8MR materials have intra-molecular sieve void spaces that are too small to allow formation of these species. The molecular sieves are tested as MTO catalysts at 400°C, and only the molecular sieves with the CHA topology show MTO activity. Post-reaction analysis of the organic content of each solid material is accomplished by HF acid digestion with subsequent 1H NMR analysis of the extracted hydrocarbon products to confirm the presence of aromatics in the 8MR materials with sufficiently large cages (those with CHA topology), and absence with materials that have smaller void spaces. These data provide further support for the necessity of polymethylbenzene species in the hydrocarbon pool for MTO activity. Springer Science+Business Media New York, 2015 Pore size in molecular sieves nationallicence Methanol-to-olefin reaction nationallicence Zeolites nationallicence Silicoaluminophosphates nationallicence Hydrocarbon pool nationallicence CHA nationallicence Deimund Mark Chemical Engineering, California Institute of Technology, 91125, Pasadena, CA, USA aut Schmidt Joel Chemical Engineering, California Institute of Technology, 91125, Pasadena, CA, USA aut Davis Mark Chemical Engineering, California Institute of Technology, 91125, Pasadena, CA, USA aut Topics in Catalysis Springer US; http://www.springer-ny.com 58/7-9(2015-05-01), 416-423 1022-5528 58:7-9<416 2015 58 11244 https://doi.org/10.1007/s11244-015-0384-y text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s11244-015-0384-y text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Deimund Mark Chemical Engineering, California Institute of Technology, 91125, Pasadena, CA, USA aut NATIONALLICENCE 700 1- Schmidt Joel Chemical Engineering, California Institute of Technology, 91125, Pasadena, CA, USA aut NATIONALLICENCE 700 1- Davis Mark Chemical Engineering, California Institute of Technology, 91125, Pasadena, CA, USA aut NATIONALLICENCE 773 0- Topics in Catalysis Springer US; http://www.springer-ny.com 58/7-9(2015-05-01), 416-423 1022-5528 58:7-9<416 2015 58 11244