Microporous Materials最新文献_第4页

Monitoring of the structure of siliceous mesoporous molecular sieves tailored using different synthesis conditions 监测不同合成条件下硅质介孔分子筛的结构

Microporous Materials Pub Date : 1997-11-01 DOI: 10.1016/S0927-6513(97)00060-6

Michal Kruk , Mietek Jaroniec , Ryong Ryoo , Ji Man Kim

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引用次数: 40

Effect of glycerol on monolithicity, density, microhardness and sintering temperature of TMOS silica aerogels 甘油对TMOS二氧化硅气凝胶的整体度、密度、显微硬度和烧结温度的影响

Microporous Materials Pub Date : 1997-11-01 DOI: 10.1016/S0927-6513(97)00066-7

A. Venkateswara Rao , G.M. Pajonk , D. Haranath , P.B. Wagh

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引用次数: 10

Electron spin resonance and electron spin echo modulation studies of Cu(II) cation locations and adsorbate interactions in ionexchanged Cu-MCM-22 zeolite 离子交换Cu- mcm -22分子筛中Cu(II)阳离子位置和吸附相互作用的电子自旋共振和电子自旋回波调制研究

Microporous Materials Pub Date : 1997-11-01 DOI: 10.1016/S0927-6513(97)00061-8

Tomasz Wasowicz, A.M. Prakash, Larry Kevan

引用次数: 8

Modification of mordenite acidity by isomorphous substitution of trivalent cations in the framework sites using the atom-planting method 原子种植法用三价阳离子在框架位上的同形取代改性丝光沸石酸性

Microporous Materials Pub Date : 1997-11-01 DOI: 10.1016/S0927-6513(97)00056-4

Peng Wu , Takayuki Komatsu , Tatsuaki Yashima , Shin-ichi Nakata , Hiroshi Shouji

{"title":"Modification of mordenite acidity by isomorphous substitution of trivalent cations in the framework sites using the atom-planting method","authors":"Peng Wu , Takayuki Komatsu , Tatsuaki Yashima , Shin-ichi Nakata , Hiroshi Shouji","doi":"10.1016/S0927-6513(97)00056-4","DOIUrl":"10.1016/S0927-6513(97)00056-4","url":null,"abstract":"<div>Aluminum, gallium and antimony cations were incorporated into the framework of highly siliceous mordenite to modify the acid strength of Bronsted acid sites by the ‘atom-planting method’ with the corresponding metal chloride vapors at elevated temperatures. The framework incorporation of metal cations was confirmed by IR, MAS NMR and catalytic reactions. The optimum temperature to achieve a maximum incorporation of metal cations into the mordenite framework was demonstrated to be 873 K. Tetrahedral Ga cations exhibited an IR band owing to acidic bridging Si(OH)Ga groups at 3620cm−1 and a characteristic band at 159 ppm in the 71Ga MAS NMR spectrum. The IR band owing to bridging Si(OH)Sb groups was observed at 3663 cm−1. The acid strength of Si(OH)Me (Me = Al, Ga and Sb) groups estimated from their IR frequency, IR spectra of adsorbed pyridine and the activity for toluene disproportionation and cumene alkylation with 2-propanol was in the order Si(OH)Al>Si(OH)Ga> > Si(OH)Sb. The weakest acid sites, Si(OH)Sb, inactive for the toluene disproportionation, showed a significant activity for the cumene alkylation with higher para-selectivity.</div>","PeriodicalId":100926,"journal":{"name":"Microporous Materials","volume":"12 1","pages":"Pages 25-37"},"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)00056-4","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85963679","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: 5

Synthesis of hexagonal Y type zeolites in the presence of Gd(III) complexes of 18-crown-6 Gd(III) 18-冠-6配合物存在下六方Y型沸石的合成

Microporous Materials Pub Date : 1997-10-01 DOI: 10.1016/S0927-6513(97)00054-0

Kenneth J. Balkus Jr., Jimin Shi

引用次数: 14

Decomposition of template in SAPO-5 and AlPO4-5 molecular sieves studied by IR and Raman spectroscopy 用红外光谱和拉曼光谱研究了模板在SAPO-5和AlPO4-5分子筛中的分解

Microporous Materials Pub Date : 1997-10-01 DOI: 10.1016/S0927-6513(97)00049-7

Karl-Heinz Schnabel , Gerd Finger , Jan Kornatowski , Elke Löffler , Christel Peuker , Walter Pilz

引用次数: 56

Alkali-free synthesis of MFI type boro-titanosilicates using methylamine 甲胺无碱合成MFI型硼钛硅酸盐

Microporous Materials Pub Date : 1997-10-01 DOI: 10.1016/S0927-6513(97)00015-1

Masashi Shibata , Zelimir Gabelica

引用次数: 5

Aluminated zeolites β and their properties II. Basicities of aluminated zeolites β: an FTIR study of chemisorbed pyrrole 铝化沸石β及其性质ⅱ。铝化沸石β的碱度:化学吸附吡咯的红外光谱研究

Microporous Materials Pub Date : 1997-10-01 DOI: 10.1016/S0927-6513(97)00044-8

Chun Yang , Jian Wang, Qinhua Xu

引用次数: 17

Microporous texture of activated carbon fibers prepared from aramid fiber pulp 芳纶纤维浆制备活性炭纤维的微孔结构

Microporous Materials Pub Date : 1997-10-01 DOI: 10.1016/S0927-6513(97)00050-3

Amelia Martínez-Alonso, Marielle Jamond, Miguel A. Montes-Morán, Juan M.D. Tascón

引用次数: 30

Zeolite Beta: characterization and passivation of the external surface acidity 沸石β:表征和钝化的外表面酸度

Microporous Materials Pub Date : 1997-10-01 DOI: 10.1016/S0927-6513(97)00053-9

Paul J. Kunkeler, Dennis Moeskops, Herman van Bekkum

引用次数: 47