Microporous Materials最新文献_第3页

Characterization of iron in Fe-VPI-5 and its thermally transformed product, FAPO-8 铁在Fe-VPI-5及其热转化产物FAPO-8中的表征

Microporous Materials Pub Date : 1997-11-01 DOI: 10.1016/S0927-6513(97)00072-2

S. Prasad

引用次数: 8

Reaction of LTA and FAU zeolites with NH4H2PO4 melts yields crystalline NH4AlP2O7 LTA和FAU沸石与NH4H2PO4熔体反应生成结晶NH4AlP2O7

Microporous Materials Pub Date : 1997-11-01 DOI: 10.1016/S0927-6513(97)00048-5

Susan M. Bradley , Russell F. Howe

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引用次数: 4

Charge sensitivity analysis of the interaction of pyrrole with basic FAU-type zeolites using the electronegativity equalization method 电负性平衡法分析吡咯与碱性fu型沸石相互作用的电荷敏感性

Microporous Materials Pub Date : 1997-11-01 DOI: 10.1016/S0927-6513(97)00039-4

Ralf Heidler, Geert O.A. Janssens, Wilfried J. Mortier, Robert A. Schoonheydt

{"title":"Charge sensitivity analysis of the interaction of pyrrole with basic FAU-type zeolites using the electronegativity equalization method","authors":"Ralf Heidler, Geert O.A. Janssens, Wilfried J. Mortier, Robert A. Schoonheydt","doi":"10.1016/S0927-6513(97)00039-4","DOIUrl":"10.1016/S0927-6513(97)00039-4","url":null,"abstract":"<div>The interaction of pyrrole with alkali cation exchanged FAU-type zeolites is studied using a combination of the electronegativity equalization method (EEM) and the Monte Carlo technique. Pyrrole adsorbs at SII cations, the NH-group pointing to the most basic oxygen O4. The NH-bond polarization and the pyrrole framework interaction energy reflect the fundamental and well established trends of the intrinsic framework basicity: an increasing basicity with an increasing Al-content and, at a given Si:Al-ratio, an increasing basicity with increasing size of the exchangeable cations. In contrast to a recent interpretation of the IR-spectra of the NH-stretching vibration of pyrrole (D. Murphy, P. Massiani, R. Franck, D. Barthomeuf, J. Phys. Chem., 100 (1996) 6731; D. Murphy, P. Massiani, R. Franck, D. Barthomeuf, Stud. Surf. Sci. Catal., 105 (1997) 639). our Monte Carlo calculations show that there is only one adsorption site for pyrrole in the FAU-structure at low loadings. An alternative explanation for the observed heterogeneity of the IR-spectra of pyrrole is discussed on the basis of our calculations: the orientation of the pyrrole molecule with respect to the six-ring depends on the Si:Al-ratio of the tetrahedra forming the six-rings.</div>","PeriodicalId":100926,"journal":{"name":"Microporous Materials","volume":"12 1","pages":"Pages 1-11"},"PeriodicalIF":0.0,"publicationDate":"1997-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0927-6513(97)00039-4","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90387203","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 9

MgAPO molecular sieves of CHA and AFI structure — Acidity and Mg ordering CHA和AFI结构的MgAPO分子筛-酸度和Mg的排序

Microporous Materials Pub Date : 1997-11-01 DOI: 10.1016/S0927-6513(97)00064-3

U. Lohse , B. Parlitz , D. Müller , E. Schreier , R. Bertram , R. Fricke

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引用次数: 11

Effect of framework aluminum on the dissolution process of ZSM-5 zeolite crystal 框架铝对ZSM-5沸石晶体溶解过程的影响

Microporous Materials Pub Date : 1997-11-01 DOI: 10.1016/S0927-6513(97)00058-8

T. Sano , Y. Nakajima , Z.B. Wang , Y. Kawakami , K. Soga , A. Iwasaki

引用次数: 21

Adsorption of normal hexane in silicalite-1: an isosteric approach 正己烷在硅石-1中的吸附:等均衡方法

Microporous Materials Pub Date : 1997-11-01 DOI: 10.1016/S0927-6513(97)00071-0

Yiwen Yang, Lovat V.C. Rees

引用次数: 22

Characterization of alumina-titania mixed oxide supports I. TiO2-based supports 氧化铝-二氧化钛混合氧化物支架的表征

Microporous Materials Pub Date : 1997-11-01 DOI: 10.1016/S0927-6513(97)00062-X

A. Gutiérrez-Alejandre , M. Trombetta , G. Busca , J. Ramírez

引用次数: 34

Rapid synthesis of MFI titanosilicates using in situ seeding method 原位播种法快速合成MFI型钛硅酸盐

Microporous Materials Pub Date : 1997-11-01 DOI: 10.1016/S0927-6513(97)00065-5

Masashi Shibata , Julien Gérard , Zelimir Gabelica

引用次数: 16

Hydrothermally resistant high-silica Y zeolites stabilized by covering with non-framework aluminum species 耐水热的高硅Y型沸石通过覆盖非框架铝来稳定

Microporous Materials Pub Date : 1997-11-01 DOI: 10.1016/S0927-6513(97)00070-9

W. Lutz, W. Gessner, R. Bertram, I. Pitsch, R. Fricke

引用次数: 42

Evidence of textural modifications of an activated carbon on liquid-phase oxidation treatments 液相氧化处理下活性炭结构改变的证据

Microporous Materials Pub Date : 1997-11-01 DOI: 10.1016/S0927-6513(97)00057-6

A. Gil , G. de la Puente , P. Grange

引用次数: 67